99 files changed, 670 insertions, 438 deletions

diff --git a/actionmailer/test/base_test.rb b/actionmailer/test/base_test.rb
index 0890448f65..1aee95b45a 100644
--- a/actionmailer/test/base_test.rb
+++ b/actionmailer/test/base_test.rb
@@ -121,7 +121,7 @@ class BaseTest < ActiveSupport::TestCase
     email = BaseMailer.attachment_with_hash
     assert_equal(1, email.attachments.length)
     assert_equal("invoice.jpg", email.attachments[0].filename)
-    expected = "\312\213\254\232)b"
+    expected = "\312\213\254\232)b".dup
     expected.force_encoding(Encoding::BINARY)
     assert_equal expected, email.attachments["invoice.jpg"].decoded
   end
@@ -130,7 +130,7 @@ class BaseTest < ActiveSupport::TestCase
     email = BaseMailer.attachment_with_hash_default_encoding
     assert_equal(1, email.attachments.length)
     assert_equal("invoice.jpg", email.attachments[0].filename)
-    expected = "\312\213\254\232)b"
+    expected = "\312\213\254\232)b".dup
     expected.force_encoding(Encoding::BINARY)
     assert_equal expected, email.attachments["invoice.jpg"].decoded
   end
diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index d3d3188d95..f8fd2403ef 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Fallback `ActionController::Parameters#to_s` to `Hash#to_s`.
+
+    *Kir Shatrov*
+
 *   `driven_by` now registers poltergeist and capybara-webkit
 
     If driver poltergeist or capybara-webkit is set for System Tests,
diff --git a/actionpack/lib/action_controller/log_subscriber.rb b/actionpack/lib/action_controller/log_subscriber.rb
index a2abc2356f..61f8adb2c1 100644
--- a/actionpack/lib/action_controller/log_subscriber.rb
+++ b/actionpack/lib/action_controller/log_subscriber.rb
@@ -25,7 +25,7 @@ module ActionController
           exception_class_name = payload[:exception].first
           status = ActionDispatch::ExceptionWrapper.status_code_for_exception(exception_class_name)
         end
-        message = "Completed #{status} #{Rack::Utils::HTTP_STATUS_CODES[status]} in #{event.duration.round}ms"
+        message = "Completed #{status} #{Rack::Utils::HTTP_STATUS_CODES[status]} in #{event.duration.round}ms".dup
         message << " (#{additions.join(" | ".freeze)})" unless additions.empty?
         message << "\n\n" if defined?(Rails.env) && Rails.env.development?
 
diff --git a/actionpack/lib/action_controller/metal/strong_parameters.rb b/actionpack/lib/action_controller/metal/strong_parameters.rb
index e0b521367e..6f57a3d626 100644
--- a/actionpack/lib/action_controller/metal/strong_parameters.rb
+++ b/actionpack/lib/action_controller/metal/strong_parameters.rb
@@ -181,6 +181,14 @@ module ActionController
     # Returns a new array of the keys of the parameters.
 
     ##
+    # :method: to_s
+    #
+    # :call-seq:
+    #   to_s()
+    #
+    # Returns the content of the parameters as a string.
+
+    ##
     # :method: value?
     #
     # :call-seq:
@@ -196,7 +204,7 @@ module ActionController
     #
     # Returns a new array of the values of the parameters.
     delegate :keys, :key?, :has_key?, :values, :has_value?, :value?, :empty?, :include?,
-      :as_json, to: :@parameters
+      :as_json, :to_s, to: :@parameters
 
     # By default, never raise an UnpermittedParameters exception if these
     # params are present. The default includes both 'controller' and 'action'
diff --git a/actionpack/lib/action_dispatch/http/response.rb b/actionpack/lib/action_dispatch/http/response.rb
index 213e7098c1..0b8f890907 100644
--- a/actionpack/lib/action_dispatch/http/response.rb
+++ b/actionpack/lib/action_dispatch/http/response.rb
@@ -104,7 +104,7 @@ module ActionDispatch # :nodoc:
 
       def body
         @str_body ||= begin
-          buf = ""
+          buf = "".dup
           each { |chunk| buf << chunk }
           buf
         end
diff --git a/actionpack/lib/action_dispatch/journey/router/utils.rb b/actionpack/lib/action_dispatch/journey/router/utils.rb
index 5d9563ee1a..87046f524f 100644
--- a/actionpack/lib/action_dispatch/journey/router/utils.rb
+++ b/actionpack/lib/action_dispatch/journey/router/utils.rb
@@ -15,11 +15,11 @@ module ActionDispatch
         #   normalize_path("/%ab")  # => "/%AB"
         def self.normalize_path(path)
           encoding = path.encoding
-          path = "/#{path}"
+          path = "/#{path}".dup
           path.squeeze!("/".freeze)
           path.sub!(%r{/+\Z}, "".freeze)
           path.gsub!(/(%[a-f0-9]{2})/) { $1.upcase }
-          path = "/" if path == "".freeze
+          path = "/".dup if path == "".freeze
           path.force_encoding(encoding)
           path
         end
@@ -30,7 +30,7 @@ module ActionDispatch
           ENCODE   = "%%%02X".freeze
           US_ASCII = Encoding::US_ASCII
           UTF_8    = Encoding::UTF_8
-          EMPTY    = "".force_encoding(US_ASCII).freeze
+          EMPTY    = "".dup.force_encoding(US_ASCII).freeze
           DEC2HEX  = (0..255).to_a.map { |i| ENCODE % i }.map { |s| s.force_encoding(US_ASCII) }
 
           ALPHA = "a-zA-Z".freeze
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index ee692e1243..3849316af5 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -74,7 +74,6 @@ module ActionDispatch
           @routes = {}
           @path_helpers = Set.new
           @url_helpers = Set.new
-          @custom_helpers = Set.new
           @url_helpers_module  = Module.new
           @path_helpers_module = Module.new
         end
@@ -97,23 +96,9 @@ module ActionDispatch
             @url_helpers_module.send  :remove_method, helper
           end
 
-          @custom_helpers.each do |helper|
-            path_name = :"#{helper}_path"
-            url_name = :"#{helper}_url"
-
-            if @path_helpers_module.method_defined?(path_name)
-              @path_helpers_module.send :remove_method, path_name
-            end
-
-            if @url_helpers_module.method_defined?(url_name)
-              @url_helpers_module.send :remove_method, url_name
-            end
-          end
-
           @routes.clear
           @path_helpers.clear
           @url_helpers.clear
-          @custom_helpers.clear
         end
 
         def add(name, route)
@@ -159,21 +144,29 @@ module ActionDispatch
           routes.length
         end
 
+        # Given a +name+, defines name_path and name_url helpers.
+        # Used by 'direct', 'resolve', and 'polymorphic' route helpers.
         def add_url_helper(name, defaults, &block)
-          @custom_helpers << name
           helper = CustomUrlHelper.new(name, defaults, &block)
+          path_name = :"#{name}_path"
+          url_name = :"#{name}_url"
 
           @path_helpers_module.module_eval do
-            define_method(:"#{name}_path") do |*args|
+            define_method(path_name) do |*args|
               helper.call(self, args, true)
             end
           end
 
           @url_helpers_module.module_eval do
-            define_method(:"#{name}_url") do |*args|
+            define_method(url_name) do |*args|
               helper.call(self, args, false)
             end
           end
+
+          @path_helpers << path_name
+          @url_helpers << url_name
+
+          self
         end
 
         class UrlHelper
diff --git a/actionpack/lib/action_dispatch/testing/assertions/response.rb b/actionpack/lib/action_dispatch/testing/assertions/response.rb
index 8c17ec5a75..918174c241 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/response.rb
@@ -80,7 +80,7 @@ module ActionDispatch
         def generate_response_message(expected, actual = @response.response_code)
           "Expected response to be a <#{code_with_name(expected)}>,"\
           " but was a <#{code_with_name(actual)}>"
-            .concat(location_if_redirected).concat(response_body_if_short)
+            .dup.concat(location_if_redirected).concat(response_body_if_short)
         end
 
         def response_body_if_short
diff --git a/actionpack/test/controller/parameters/accessors_test.rb b/actionpack/test/controller/parameters/accessors_test.rb
index 05e80a162d..e9c9d175ec 100644
--- a/actionpack/test/controller/parameters/accessors_test.rb
+++ b/actionpack/test/controller/parameters/accessors_test.rb
@@ -36,6 +36,11 @@ class ParametersAccessorsTest < ActiveSupport::TestCase
     assert @params.as_json.key? "person"
   end
 
+  test "to_s returns the string representation of the parameters hash" do
+    assert_equal '{"person"=>{"age"=>"32", "name"=>{"first"=>"David", "last"=>"Heinemeier Hansson"}, ' \
+      '"addresses"=>[{"city"=>"Chicago", "state"=>"Illinois"}]}}', @params.to_s
+  end
+
   test "each carries permitted status" do
     @params.permit!
     @params.each { |key, value| assert(value.permitted?) if key == "person" }
diff --git a/actionpack/test/dispatch/routing/custom_url_helpers_test.rb b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
index d9a30fa42f..340b07a929 100644
--- a/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
+++ b/actionpack/test/dispatch/routing/custom_url_helpers_test.rb
@@ -323,4 +323,10 @@ class TestCustomUrlHelpers < ActionDispatch::IntegrationTest
       end
     end
   end
+
+  def test_defining_direct_url_registers_helper_method
+    assert_equal "http://www.example.com/basket", Routes.url_helpers.symbol_url
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_url), "'symbol_url' named helper not found"
+    assert_equal true, Routes.named_routes.route_defined?(:symbol_path), "'symbol_path' named helper not found"
+  end
 end
diff --git a/actionview/CHANGELOG.md b/actionview/CHANGELOG.md
index e618183129..5bc93fcb5b 100644
--- a/actionview/CHANGELOG.md
+++ b/actionview/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Add `srcset` option to `image_tag` helper.
+
+    *Roberto Miranda*
+
 *   Fix issues with scopes and engine on `current_page?` method.
 
     Fixes #29401.
diff --git a/actionview/lib/action_view/helpers/asset_tag_helper.rb b/actionview/lib/action_view/helpers/asset_tag_helper.rb
index 791454ca87..cfb6579f67 100644
--- a/actionview/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_tag_helper.rb
@@ -204,13 +204,15 @@ module ActionView
       # ==== Options
       #
       # You can add HTML attributes using the +options+. The +options+ supports
-      # two additional keys for convenience and conformance:
+      # additional keys for convenience and conformance:
       #
       # * <tt>:alt</tt>  - If no alt text is given, the file name part of the
       #   +source+ is used (capitalized and without the extension)
       # * <tt>:size</tt> - Supplied as "{Width}x{Height}" or "{Number}", so "30x45" becomes
       #   width="30" and height="45", and "50" becomes width="50" and height="50".
       #   <tt>:size</tt> will be ignored if the value is not in the correct format.
+      # * <tt>:srcset</tt> - If supplied as a hash or array of <tt>[source, descriptor]</tt>
+      #   pairs, each image path will be expanded before the list is formatted as a string.
       #
       # ==== Examples
       #
@@ -228,16 +230,28 @@ module ActionView
       #   # => <img alt="Icon" class="menu_icon" src="/icons/icon.gif" />
       #   image_tag("/icons/icon.gif", data: { title: 'Rails Application' })
       #   # => <img data-title="Rails Application" src="/icons/icon.gif" />
+      #   image_tag("icon.png", srcset: { "icon_2x.png" => "2x", "icon_4x.png" => "4x" })
+      #   # => <img src="/assets/icon.png" srcset="/assets/icon_2x.png 2x, /assets/icon_4x.png 4x">
+      #   image_tag("pic.jpg", srcset: [["pic_1024.jpg", "1024w"], ["pic_1980.jpg", "1980w"]], sizes: "100vw")
+      #   # => <img src="/assets/pic.jpg" srcset="/assets/pic_1024.jpg 1024w, /assets/pic_1980.jpg 1980w" sizes="100vw">
       def image_tag(source, options = {})
         options = options.symbolize_keys
         check_for_image_tag_errors(options)
+        skip_pipeline = options.delete(:skip_pipeline)
 
-        src = options[:src] = path_to_image(source, skip_pipeline: options.delete(:skip_pipeline))
+        src = options[:src] = path_to_image(source, skip_pipeline: skip_pipeline)
 
         unless src.start_with?("cid:") || src.start_with?("data:") || src.blank?
           options[:alt] = options.fetch(:alt) { image_alt(src) }
         end
 
+        if options[:srcset] && !options[:srcset].is_a?(String)
+          options[:srcset] = options[:srcset].map do |src, size|
+            src_path = path_to_image(src, skip_pipeline: skip_pipeline)
+            "#{src_path} #{size}"
+          end.join(", ")
+        end
+
         options[:width], options[:height] = extract_dimensions(options.delete(:size)) if options[:size]
         tag("img", options)
       end
diff --git a/actionview/lib/action_view/helpers/date_helper.rb b/actionview/lib/action_view/helpers/date_helper.rb
index 2c30f88c3b..552d9cfeab 100644
--- a/actionview/lib/action_view/helpers/date_helper.rb
+++ b/actionview/lib/action_view/helpers/date_helper.rb
@@ -1008,7 +1008,7 @@ module ActionView
           select_options[:disabled] = "disabled" if @options[:disabled]
           select_options[:class] = css_class_attribute(type, select_options[:class], @options[:with_css_classes]) if @options[:with_css_classes]
 
-          select_html = "\n"
+          select_html = "\n".dup
           select_html << content_tag("option".freeze, "", value: "") + "\n" if @options[:include_blank]
           select_html << prompt_option_tag(type, @options[:prompt]) + "\n" if @options[:prompt]
           select_html << select_options_as_html
@@ -1090,7 +1090,7 @@ module ActionView
         # Given an ordering of datetime components, create the selection HTML
         # and join them with their appropriate separators.
         def build_selects_from_types(order)
-          select = ""
+          select = "".dup
           first_visible = order.find { |type| !@options[:"discard_#{type}"] }
           order.reverse_each do |type|
             separator = separator(type) unless type == first_visible # don't add before first visible field
diff --git a/actionview/lib/action_view/helpers/javascript_helper.rb b/actionview/lib/action_view/helpers/javascript_helper.rb
index 2c93647534..6dfbdcac40 100644
--- a/actionview/lib/action_view/helpers/javascript_helper.rb
+++ b/actionview/lib/action_view/helpers/javascript_helper.rb
@@ -14,8 +14,8 @@ module ActionView
         "'"     => "\\'"
       }
 
-      JS_ESCAPE_MAP["\342\200\250".force_encoding(Encoding::UTF_8).encode!] = "&#x2028;"
-      JS_ESCAPE_MAP["\342\200\251".force_encoding(Encoding::UTF_8).encode!] = "&#x2029;"
+      JS_ESCAPE_MAP["\342\200\250".dup.force_encoding(Encoding::UTF_8).encode!] = "&#x2028;"
+      JS_ESCAPE_MAP["\342\200\251".dup.force_encoding(Encoding::UTF_8).encode!] = "&#x2029;"
 
       # Escapes carriage returns and single and double quotes for JavaScript segments.
       #
diff --git a/actionview/lib/action_view/helpers/translation_helper.rb b/actionview/lib/action_view/helpers/translation_helper.rb
index a1f8b6307c..a28acdf1f6 100644
--- a/actionview/lib/action_view/helpers/translation_helper.rb
+++ b/actionview/lib/action_view/helpers/translation_helper.rb
@@ -96,7 +96,7 @@ module ActionView
           raise e if raise_error
 
           keys = I18n.normalize_keys(e.locale, e.key, e.options[:scope])
-          title = "translation missing: #{keys.join('.')}"
+          title = "translation missing: #{keys.join('.')}".dup
 
           interpolations = options.except(:default, :scope)
           if interpolations.any?
diff --git a/actionview/lib/action_view/log_subscriber.rb b/actionview/lib/action_view/log_subscriber.rb
index dd8729adf7..deacf2d001 100644
--- a/actionview/lib/action_view/log_subscriber.rb
+++ b/actionview/lib/action_view/log_subscriber.rb
@@ -15,7 +15,7 @@ module ActionView
 
     def render_template(event)
       info do
-        message = "  Rendered #{from_rails_root(event.payload[:identifier])}"
+        message = "  Rendered #{from_rails_root(event.payload[:identifier])}".dup
         message << " within #{from_rails_root(event.payload[:layout])}" if event.payload[:layout]
         message << " (#{event.duration.round(1)}ms)"
       end
@@ -23,7 +23,7 @@ module ActionView
 
     def render_partial(event)
       info do
-        message = "  Rendered #{from_rails_root(event.payload[:identifier])}"
+        message = "  Rendered #{from_rails_root(event.payload[:identifier])}".dup
         message << " within #{from_rails_root(event.payload[:layout])}" if event.payload[:layout]
         message << " (#{event.duration.round(1)}ms)"
         message << " #{cache_message(event.payload)}" unless event.payload[:cache_hit].nil?
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index ccd8af2559..80b294dc3d 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -283,7 +283,7 @@ module ActionView
 
         # Make sure that the resulting String to be eval'd is in the
         # encoding of the code
-        source = <<-end_src
+        source = <<-end_src.dup
           def #{method_name}(local_assigns, output_buffer)
             _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
           ensure
@@ -330,12 +330,12 @@ module ActionView
         locals = locals.grep(/\A@?(?![A-Z0-9])(?:[[:alnum:]_]|[^\0-\177])+\z/)
 
         # Double assign to suppress the dreaded 'assigned but unused variable' warning
-        locals.each_with_object("") { |key, code| code << "#{key} = #{key} = local_assigns[:#{key}];" }
+        locals.each_with_object("".dup) { |key, code| code << "#{key} = #{key} = local_assigns[:#{key}];" }
       end
 
       def method_name
         @method_name ||= begin
-          m = "_#{identifier_method_name}__#{@identifier.hash}_#{__id__}"
+          m = "_#{identifier_method_name}__#{@identifier.hash}_#{__id__}".dup
           m.tr!("-".freeze, "_".freeze)
           m
         end
diff --git a/actionview/lib/action_view/template/resolver.rb b/actionview/lib/action_view/template/resolver.rb
index 32d2db3e57..837396bdfd 100644
--- a/actionview/lib/action_view/template/resolver.rb
+++ b/actionview/lib/action_view/template/resolver.rb
@@ -15,7 +15,7 @@ module ActionView
       alias_method :partial?, :partial
 
       def self.build(name, prefix, partial)
-        virtual = ""
+        virtual = "".dup
         virtual << "#{prefix}/" unless prefix.empty?
         virtual << (partial ? "_#{name}" : name)
         new name, prefix, partial, virtual
diff --git a/actionview/lib/action_view/test_case.rb b/actionview/lib/action_view/test_case.rb
index f149d66bf9..0df1314395 100644
--- a/actionview/lib/action_view/test_case.rb
+++ b/actionview/lib/action_view/test_case.rb
@@ -105,7 +105,7 @@ module ActionView
         # empty string ensures buffer has UTF-8 encoding as
         # new without arguments returns ASCII-8BIT encoded buffer like String#new
         @output_buffer = ActiveSupport::SafeBuffer.new ""
-        @rendered = ""
+        @rendered = "".dup
 
         make_test_case_available_to_view!
         say_no_to_protect_against_forgery!
diff --git a/actionview/lib/action_view/testing/resolvers.rb b/actionview/lib/action_view/testing/resolvers.rb
index 4e7fe43066..acd5dc4cb4 100644
--- a/actionview/lib/action_view/testing/resolvers.rb
+++ b/actionview/lib/action_view/testing/resolvers.rb
@@ -21,7 +21,7 @@ module ActionView #:nodoc:
     private
 
       def query(path, exts, _, _)
-        query = ""
+        query = "".dup
         EXTENSIONS.each_key do |ext|
           query << "(" << exts[ext].map { |e| e && Regexp.escape(".#{e}") }.join("|") << "|)"
         end
diff --git a/actionview/test/activerecord/form_helper_activerecord_test.rb b/actionview/test/activerecord/form_helper_activerecord_test.rb
index 291568c672..099b5322ab 100644
--- a/actionview/test/activerecord/form_helper_activerecord_test.rb
+++ b/actionview/test/activerecord/form_helper_activerecord_test.rb
@@ -56,7 +56,7 @@ class FormHelperActiveRecordTest < ActionView::TestCase
   private
 
     def hidden_fields(method = nil)
-      txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}
+      txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
 
       if method && !%w(get post).include?(method.to_s)
         txt << %{<input name="_method" type="hidden" value="#{method}" />}
@@ -66,7 +66,7 @@ class FormHelperActiveRecordTest < ActionView::TestCase
     end
 
     def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
-      txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
       txt << %{ enctype="multipart/form-data"} if multipart
       txt << %{ data-remote="true"} if remote
       txt << %{ class="#{html_class}"} if html_class
diff --git a/actionview/test/fixtures/ruby_template.ruby b/actionview/test/fixtures/ruby_template.ruby
index cae21339f5..17eda89ad7 100644
--- a/actionview/test/fixtures/ruby_template.ruby
+++ b/actionview/test/fixtures/ruby_template.ruby
@@ -1,3 +1,3 @@
 # frozen_string_literal: true
-body = ""
+body = "".dup
 body << ["Hello", "from", "Ruby", "code"].join(" ")
diff --git a/actionview/test/template/asset_tag_helper_test.rb b/actionview/test/template/asset_tag_helper_test.rb
index 5bdcbda72e..3f837ffc33 100644
--- a/actionview/test/template/asset_tag_helper_test.rb
+++ b/actionview/test/template/asset_tag_helper_test.rb
@@ -198,7 +198,10 @@ class AssetTagHelperTest < ActionView::TestCase
     %(image_tag("mouse.png", :alt => nil)) => %(<img src="/images/mouse.png" />),
     %(image_tag("data:image/gif;base64,R0lGODlhAQABAID/AMDAwAAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==", :alt => nil)) => %(<img src="data:image/gif;base64,R0lGODlhAQABAID/AMDAwAAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" />),
     %(image_tag("")) => %(<img src="" />),
-    %(image_tag("gold.png", data: { title: 'Rails Application' })) => %(<img data-title="Rails Application" src="/images/gold.png" alt="Gold" />)
+    %(image_tag("gold.png", data: { title: 'Rails Application' })) => %(<img data-title="Rails Application" src="/images/gold.png" alt="Gold" />),
+    %(image_tag("rss.gif", srcset: "/assets/pic_640.jpg 640w, /assets/pic_1024.jpg 1024w")) => %(<img srcset="/assets/pic_640.jpg 640w, /assets/pic_1024.jpg 1024w" src="/images/rss.gif" alt="Rss" />),
+    %(image_tag("rss.gif", srcset: { "pic_640.jpg" => "640w", "pic_1024.jpg" => "1024w" })) => %(<img srcset="/images/pic_640.jpg 640w, /images/pic_1024.jpg 1024w" src="/images/rss.gif" alt="Rss" />),
+    %(image_tag("rss.gif", srcset: [["pic_640.jpg", "640w"], ["pic_1024.jpg", "1024w"]])) => %(<img srcset="/images/pic_640.jpg 640w, /images/pic_1024.jpg 1024w" src="/images/rss.gif" alt="Rss" />)
   }
 
   FaviconLinkToTag = {
diff --git a/actionview/test/template/atom_feed_helper_test.rb b/actionview/test/template/atom_feed_helper_test.rb
index 4a1188922c..fd31dd09f8 100644
--- a/actionview/test/template/atom_feed_helper_test.rb
+++ b/actionview/test/template/atom_feed_helper_test.rb
@@ -195,7 +195,7 @@ class ScrollsController < ActionController::Base
   FEEDS["provide_builder"] = <<-'EOT'
           # we pass in the new_xml to the helper so it doesn't
           # call anything on the original builder
-          new_xml = Builder::XmlMarkup.new(:target=>'')
+          new_xml = Builder::XmlMarkup.new(:target=>''.dup)
           atom_feed(:xml => new_xml) do |feed|
             feed.title("My great blog!")
             feed.updated(@scrolls.first.created_at)
diff --git a/actionview/test/template/date_helper_test.rb b/actionview/test/template/date_helper_test.rb
index 72573917fa..235ac9f338 100644
--- a/actionview/test/template/date_helper_test.rb
+++ b/actionview/test/template/date_helper_test.rb
@@ -215,7 +215,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -224,7 +224,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_blank
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -233,7 +233,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_nil_with_blank
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -241,7 +241,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_two_digit_numbers
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="1">01</option>\n<option selected="selected" value="2">02</option>\n<option value="3">03</option>\n<option value="4">04</option>\n<option value="5">05</option>\n<option value="6">06</option>\n<option value="7">07</option>\n<option value="8">08</option>\n<option value="9">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -250,7 +250,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_html_options
-    expected = %(<select id="date_day" name="date[day]" class="selector">\n)
+    expected = %(<select id="date_day" name="date[day]" class="selector">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -259,7 +259,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_default_prompt
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="">Day</option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -267,7 +267,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_custom_prompt
-    expected = %(<select id="date_day" name="date[day]">\n)
+    expected = %(<select id="date_day" name="date[day]">\n).dup
     expected << %(<option value="">Choose day</option>\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -275,7 +275,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_generic_with_css_classes
-    expected = %(<select id="date_day" name="date[day]" class="day">\n)
+    expected = %(<select id="date_day" name="date[day]" class="day">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -283,7 +283,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_day_with_custom_with_css_classes
-    expected = %(<select id="date_day" name="date[day]" class="my-day">\n)
+    expected = %(<select id="date_day" name="date[day]" class="my-day">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16" selected="selected">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n)
     expected << "</select>\n"
 
@@ -291,7 +291,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -300,7 +300,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_two_digit_numbers
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">01</option>\n<option value="2">02</option>\n<option value="3">03</option>\n<option value="4">04</option>\n<option value="5">05</option>\n<option value="6">06</option>\n<option value="7">07</option>\n<option value="8" selected="selected">08</option>\n<option value="9">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n)
     expected << "</select>\n"
 
@@ -309,7 +309,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_disabled
-    expected = %(<select id="date_month" name="date[month]" disabled="disabled">\n)
+    expected = %(<select id="date_month" name="date[month]" disabled="disabled">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -318,7 +318,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_field_name_override
-    expected = %(<select id="date_mois" name="date[mois]">\n)
+    expected = %(<select id="date_mois" name="date[mois]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -327,7 +327,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_blank
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -336,7 +336,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_nil_with_blank
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value=""></option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -344,7 +344,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_numbers
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8" selected="selected">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n)
     expected << "</select>\n"
 
@@ -353,7 +353,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_numbers_and_names
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1 - January</option>\n<option value="2">2 - February</option>\n<option value="3">3 - March</option>\n<option value="4">4 - April</option>\n<option value="5">5 - May</option>\n<option value="6">6 - June</option>\n<option value="7">7 - July</option>\n<option value="8" selected="selected">8 - August</option>\n<option value="9">9 - September</option>\n<option value="10">10 - October</option>\n<option value="11">11 - November</option>\n<option value="12">12 - December</option>\n)
     expected << "</select>\n"
 
@@ -362,7 +362,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_format_string
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">January (01)</option>\n<option value="2">February (02)</option>\n<option value="3">March (03)</option>\n<option value="4">April (04)</option>\n<option value="5">May (05)</option>\n<option value="6">June (06)</option>\n<option value="7">July (07)</option>\n<option value="8" selected="selected">August (08)</option>\n<option value="9">September (09)</option>\n<option value="10">October (10)</option>\n<option value="11">November (11)</option>\n<option value="12">December (12)</option>\n)
     expected << "</select>\n"
 
@@ -372,7 +372,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_numbers_and_names_with_abbv
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">1 - Jan</option>\n<option value="2">2 - Feb</option>\n<option value="3">3 - Mar</option>\n<option value="4">4 - Apr</option>\n<option value="5">5 - May</option>\n<option value="6">6 - Jun</option>\n<option value="7">7 - Jul</option>\n<option value="8" selected="selected">8 - Aug</option>\n<option value="9">9 - Sep</option>\n<option value="10">10 - Oct</option>\n<option value="11">11 - Nov</option>\n<option value="12">12 - Dec</option>\n)
     expected << "</select>\n"
 
@@ -381,7 +381,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_abbv
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="1">Jan</option>\n<option value="2">Feb</option>\n<option value="3">Mar</option>\n<option value="4">Apr</option>\n<option value="5">May</option>\n<option value="6">Jun</option>\n<option value="7">Jul</option>\n<option value="8" selected="selected">Aug</option>\n<option value="9">Sep</option>\n<option value="10">Oct</option>\n<option value="11">Nov</option>\n<option value="12">Dec</option>\n)
     expected << "</select>\n"
 
@@ -392,7 +392,7 @@ class DateHelperTest < ActionView::TestCase
   def test_select_month_with_custom_names
     month_names = %w(nil Januar Februar Marts April Maj Juni Juli August September Oktober November December)
 
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     1.upto(12) { |month| expected << %(<option value="#{month}"#{' selected="selected"' if month == 8}>#{month_names[month]}</option>\n) }
     expected << "</select>\n"
 
@@ -403,7 +403,7 @@ class DateHelperTest < ActionView::TestCase
   def test_select_month_with_zero_indexed_custom_names
     month_names = %w(Januar Februar Marts April Maj Juni Juli August September Oktober November December)
 
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     1.upto(12) { |month| expected << %(<option value="#{month}"#{' selected="selected"' if month == 8}>#{month_names[month - 1]}</option>\n) }
     expected << "</select>\n"
 
@@ -420,7 +420,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_html_options
-    expected = %(<select id="date_month" name="date[month]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_month" name="date[month]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -428,7 +428,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_default_prompt
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="">Month</option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -436,7 +436,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_custom_prompt
-    expected = %(<select id="date_month" name="date[month]">\n)
+    expected = %(<select id="date_month" name="date[month]">\n).dup
     expected << %(<option value="">Choose month</option>\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -444,7 +444,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_generic_with_css_classes
-    expected = %(<select id="date_month" name="date[month]" class="month">\n)
+    expected = %(<select id="date_month" name="date[month]" class="month">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -452,7 +452,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_month_with_custom_with_css_classes
-    expected = %(<select id="date_month" name="date[month]" class="my-month">\n)
+    expected = %(<select id="date_month" name="date[month]" class="my-month">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -460,7 +460,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -469,7 +469,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_disabled
-    expected = %(<select id="date_year" name="date[year]" disabled="disabled">\n)
+    expected = %(<select id="date_year" name="date[year]" disabled="disabled">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -478,7 +478,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_field_name_override
-    expected = %(<select id="date_annee" name="date[annee]">\n)
+    expected = %(<select id="date_annee" name="date[annee]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -487,7 +487,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_type_discarding
-    expected = %(<select id="date_year" name="date_year">\n)
+    expected = %(<select id="date_year" name="date_year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -498,7 +498,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_descending
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="2005" selected="selected">2005</option>\n<option value="2004">2004</option>\n<option value="2003">2003</option>\n)
     expected << "</select>\n"
 
@@ -515,7 +515,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_html_options
-    expected = %(<select id="date_year" name="date[year]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_year" name="date[year]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -523,7 +523,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_default_prompt
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="">Year</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -531,7 +531,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_custom_prompt
-    expected = %(<select id="date_year" name="date[year]">\n)
+    expected = %(<select id="date_year" name="date[year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -539,7 +539,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_generic_with_css_classes
-    expected = %(<select id="date_year" name="date[year]" class="year">\n)
+    expected = %(<select id="date_year" name="date[year]" class="year">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -547,7 +547,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_custom_with_css_classes
-    expected = %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected = %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -555,14 +555,14 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_year_with_position
-    expected = %(<select id="date_year_1i" name="date[year(1i)]">\n)
+    expected = %(<select id="date_year_1i" name="date[year(1i)]">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
     assert_dom_equal expected, select_year(Date.current, include_position: true,  start_year: 2003, end_year: 2005)
   end
 
   def test_select_hour
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -570,7 +570,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_ampm
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="00">12 AM</option>\n<option value="01">01 AM</option>\n<option value="02">02 AM</option>\n<option value="03">03 AM</option>\n<option value="04">04 AM</option>\n<option value="05">05 AM</option>\n<option value="06">06 AM</option>\n<option value="07">07 AM</option>\n<option value="08" selected="selected">08 AM</option>\n<option value="09">09 AM</option>\n<option value="10">10 AM</option>\n<option value="11">11 AM</option>\n<option value="12">12 PM</option>\n<option value="13">01 PM</option>\n<option value="14">02 PM</option>\n<option value="15">03 PM</option>\n<option value="16">04 PM</option>\n<option value="17">05 PM</option>\n<option value="18">06 PM</option>\n<option value="19">07 PM</option>\n<option value="20">08 PM</option>\n<option value="21">09 PM</option>\n<option value="22">10 PM</option>\n<option value="23">11 PM</option>\n)
     expected << "</select>\n"
 
@@ -578,7 +578,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_disabled
-    expected = %(<select id="date_hour" name="date[hour]" disabled="disabled">\n)
+    expected = %(<select id="date_hour" name="date[hour]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -586,7 +586,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_field_name_override
-    expected = %(<select id="date_heure" name="date[heure]">\n)
+    expected = %(<select id="date_heure" name="date[heure]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -594,7 +594,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_blank
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -602,7 +602,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_nil_with_blank
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -610,7 +610,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_html_options
-    expected = %(<select id="date_hour" name="date[hour]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -618,7 +618,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_default_prompt
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="">Hour</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -626,7 +626,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_custom_prompt
-    expected = %(<select id="date_hour" name="date[hour]">\n)
+    expected = %(<select id="date_hour" name="date[hour]">\n).dup
     expected << %(<option value="">Choose hour</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -634,7 +634,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_generic_with_css_classes
-    expected = %(<select id="date_hour" name="date[hour]" class="hour">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="hour">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -642,7 +642,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_hour_with_custom_with_css_classes
-    expected = %(<select id="date_hour" name="date[hour]" class="my-hour">\n)
+    expected = %(<select id="date_hour" name="date[hour]" class="my-hour">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08" selected="selected">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n)
     expected << "</select>\n"
 
@@ -650,7 +650,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -658,7 +658,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_disabled
-    expected = %(<select id="date_minute" name="date[minute]" disabled="disabled">\n)
+    expected = %(<select id="date_minute" name="date[minute]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -666,7 +666,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_field_name_override
-    expected = %(<select id="date_minuto" name="date[minuto]">\n)
+    expected = %(<select id="date_minuto" name="date[minuto]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -674,7 +674,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_blank
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -682,7 +682,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_blank_and_step
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="15">15</option>\n<option value="30">30</option>\n<option value="45">45</option>\n)
     expected << "</select>\n"
 
@@ -690,7 +690,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_nil_with_blank
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -698,7 +698,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_nil_with_blank_and_step
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="15">15</option>\n<option value="30">30</option>\n<option value="45">45</option>\n)
     expected << "</select>\n"
 
@@ -714,7 +714,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_html_options
-    expected = %(<select id="date_minute" name="date[minute]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -722,7 +722,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_default_prompt
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="">Minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -730,7 +730,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_custom_prompt
-    expected = %(<select id="date_minute" name="date[minute]">\n)
+    expected = %(<select id="date_minute" name="date[minute]">\n).dup
     expected << %(<option value="">Choose minute</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -738,7 +738,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_generic_with_css_classes
-    expected = %(<select id="date_minute" name="date[minute]" class="minute">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="minute">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -746,7 +746,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_minute_with_custom_with_css_classes
-    expected = %(<select id="date_minute" name="date[minute]" class="my-minute">\n)
+    expected = %(<select id="date_minute" name="date[minute]" class="my-minute">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04" selected="selected">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -754,7 +754,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -762,7 +762,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_disabled
-    expected = %(<select id="date_second" name="date[second]" disabled="disabled">\n)
+    expected = %(<select id="date_second" name="date[second]" disabled="disabled">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -770,7 +770,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_field_name_override
-    expected = %(<select id="date_segundo" name="date[segundo]">\n)
+    expected = %(<select id="date_segundo" name="date[segundo]">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -778,7 +778,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_blank
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -786,7 +786,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_nil_with_blank
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value=""></option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -794,7 +794,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_html_options
-    expected = %(<select id="date_second" name="date[second]" class="selector" accesskey="M">\n)
+    expected = %(<select id="date_second" name="date[second]" class="selector" accesskey="M">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -802,7 +802,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_default_prompt
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="">Seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -810,7 +810,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_custom_prompt
-    expected = %(<select id="date_second" name="date[second]">\n)
+    expected = %(<select id="date_second" name="date[second]">\n).dup
     expected << %(<option value="">Choose seconds</option>\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -818,7 +818,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_generic_with_css_classes
-    expected = %(<select id="date_second" name="date[second]" class="second">\n)
+    expected = %(<select id="date_second" name="date[second]" class="second">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -826,7 +826,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_second_with_custom_with_css_classes
-    expected = %(<select id="date_second" name="date[second]" class="my-second">\n)
+    expected = %(<select id="date_second" name="date[second]" class="my-second">\n).dup
     expected << %(<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18" selected="selected">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n<option value="32">32</option>\n<option value="33">33</option>\n<option value="34">34</option>\n<option value="35">35</option>\n<option value="36">36</option>\n<option value="37">37</option>\n<option value="38">38</option>\n<option value="39">39</option>\n<option value="40">40</option>\n<option value="41">41</option>\n<option value="42">42</option>\n<option value="43">43</option>\n<option value="44">44</option>\n<option value="45">45</option>\n<option value="46">46</option>\n<option value="47">47</option>\n<option value="48">48</option>\n<option value="49">49</option>\n<option value="50">50</option>\n<option value="51">51</option>\n<option value="52">52</option>\n<option value="53">53</option>\n<option value="54">54</option>\n<option value="55">55</option>\n<option value="56">56</option>\n<option value="57">57</option>\n<option value="58">58</option>\n<option value="59">59</option>\n)
     expected << "</select>\n"
 
@@ -834,7 +834,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -859,7 +859,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_order
-    expected = %(<select id="date_first_month" name="date[first][month]">\n)
+    expected = %(<select id="date_first_month" name="date[first][month]">\n).dup
     expected << %(<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6">June</option>\n<option value="7">July</option>\n<option value="8" selected="selected">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n)
     expected << "</select>\n"
 
@@ -876,7 +876,7 @@ class DateHelperTest < ActionView::TestCase
 
   def test_select_date_with_incomplete_order
     # Since the order is incomplete nothing will be shown
-    expected = %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected = %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="1" />\n)
 
@@ -884,7 +884,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_disabled
-    expected =  %(<select id="date_first_year" name="date[first][year]" disabled="disabled">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" disabled="disabled">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -900,7 +900,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_no_start_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 1) do |y|
       if y == Date.today.year
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
@@ -924,7 +924,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_no_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     2003.upto(2008) do |y|
       if y == 2003
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
@@ -948,7 +948,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_no_start_or_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) do |y|
       if y == Date.today.year
         expected << %(<option value="#{y}" selected="selected">#{y}</option>\n)
@@ -972,7 +972,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_zero_value
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -988,7 +988,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_zero_value_and_no_start_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -1004,7 +1004,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_zero_value_and_no_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     last_year = Time.now.year + 5
     2003.upto(last_year) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
@@ -1021,7 +1021,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_zero_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -1037,7 +1037,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_nil_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -1053,7 +1053,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_html_options
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1069,7 +1069,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_separator
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1089,7 +1089,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_separator_and_discard_day
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1105,7 +1105,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_separator_discard_month_and_day
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1116,7 +1116,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003"/>\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003"/>\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
 
@@ -1125,7 +1125,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_css_classes_option
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="year">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1141,7 +1141,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_custom_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1157,7 +1157,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_css_classes_option_and_html_class_option
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="datetime optional year">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="datetime optional year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1173,7 +1173,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_custom_with_css_classes_and_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1189,7 +1189,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_partial_with_css_classes_and_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1205,7 +1205,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_date_with_html_class_option
-    expected =  %(<select id="date_year" name="date[year]" class="date optional custom-grid">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="date optional custom-grid">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1221,7 +1221,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1249,7 +1249,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_ampm
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1277,7 +1277,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_separators
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1305,7 +1305,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_nil_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -1333,7 +1333,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_html_options
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1361,7 +1361,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_all_separators
-    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]" class="selector">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1397,7 +1397,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_default_prompt
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1426,7 +1426,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_custom_prompt
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1455,7 +1455,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_generic_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1483,7 +1483,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_custom_with_css_classes
-    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n)
+    expected =  %(<select id="date_year" name="date[year]" class="my-year">\n).dup
     expected << %(<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1511,7 +1511,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_custom_hours
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     expected << %(<option value="">Choose year</option>\n<option value="2003" selected="selected">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n)
     expected << "</select>\n"
 
@@ -1540,7 +1540,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_datetime_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
     expected << %(<input id="date_first_hour" name="date[first][hour]" type="hidden" value="8" />\n)
@@ -1552,7 +1552,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1571,7 +1571,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_ampm
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1589,7 +1589,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_separator
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
     expected << %(<select id="date_hour" name="date[hour]">\n)
@@ -1607,7 +1607,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_seconds
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1631,7 +1631,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_seconds_and_separator
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1655,7 +1655,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_html_options
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1678,7 +1678,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_default_prompt
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1702,7 +1702,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_custom_prompt
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1727,7 +1727,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_generic_with_css_classes
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1751,7 +1751,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_custom_with_css_classes
-    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n)
+    expected = %(<input name="date[year]" id="date_year" value="2003" type="hidden" />\n).dup
     expected << %(<input name="date[month]" id="date_month" value="8" type="hidden" />\n)
     expected << %(<input name="date[day]" id="date_day" value="16" type="hidden" />\n)
 
@@ -1775,7 +1775,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_select_time_with_hidden
-    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n)
+    expected =  %(<input id="date_first_year" name="date[first][year]" type="hidden" value="2003" />\n).dup
     expected << %(<input id="date_first_month" name="date[first][month]" type="hidden" value="8" />\n)
     expected << %(<input id="date_first_day" name="date[first][day]" type="hidden" value="16" />\n)
     expected << %(<input id="date_first_hour" name="date[first][hour]" type="hidden" value="8" />\n)
@@ -1789,7 +1789,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1809,7 +1809,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1829,7 +1829,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -1867,7 +1867,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
     expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
@@ -1884,7 +1884,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 2, 29)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_2i\" name=\"post[written_on(2i)]\" value=\"2\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_2i\" name=\"post[written_on(2i)]\" value=\"2\" />\n".dup
     expected << "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
 
     expected << %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
@@ -1898,7 +1898,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
     expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
@@ -1917,7 +1917,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" disabled=\"disabled\" name=\"post[written_on(3i)]\" value=\"1\" />\n"
+    expected = "<input type=\"hidden\" id=\"post_written_on_3i\" disabled=\"disabled\" name=\"post[written_on(3i)]\" value=\"1\" />\n".dup
 
     expected << %{<select id="post_written_on_2i" disabled="disabled" name="post[written_on(2i)]">\n}
     expected << %{<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option value="6" selected="selected">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n}
@@ -1938,7 +1938,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.date_select(:written_on)
     end
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1954,7 +1954,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.date_select(:written_on)
     end
 
-    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_#{id}_written_on_2i" name="post[#{id}][written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_#{id}_written_on_3i" name="post[#{id}][written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1970,7 +1970,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.date_select(:written_on)
     end
 
-    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_#{id}_written_on_1i" name="post[#{id}][written_on(1i)]">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_#{id}_written_on_2i" name="post[#{id}][written_on(2i)]">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_#{id}_written_on_3i" name="post[#{id}][written_on(3i)]">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
 
@@ -1982,7 +1982,7 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = 456
 
-    expected = %{<select id="post_456_written_on_1i" name="post[#{id}][written_on(1i)]">\n}
+    expected = %{<select id="post_456_written_on_1i" name="post[#{id}][written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2002,7 +2002,7 @@ class DateHelperTest < ActionView::TestCase
     @post.written_on = Date.new(2004, 6, 15)
     id = 123
 
-    expected = %{<select id="post_123_written_on_1i" name="post[#{id}][written_on(1i)]">\n}
+    expected = %{<select id="post_123_written_on_1i" name="post[#{id}][written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2021,7 +2021,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
 
@@ -2041,7 +2041,7 @@ class DateHelperTest < ActionView::TestCase
 
     start_year = Time.now.year - 5
     end_year   = Time.now.year + 5
-    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == Time.now.year}>#{i}</option>\n) }
     expected << "</select>\n"
 
@@ -2061,7 +2061,7 @@ class DateHelperTest < ActionView::TestCase
 
     start_year = Time.now.year - 5
     end_year   = Time.now.year + 5
-    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected =   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << "<option value=\"\"></option>\n"
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -2105,7 +2105,7 @@ class DateHelperTest < ActionView::TestCase
     start_year = Time.now.year - 5
     end_year   = Time.now.year + 5
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << "<option value=\"\"></option>\n"
     start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -2137,7 +2137,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2156,7 +2156,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2180,7 +2180,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.date_select(:written_on, {}, class: "selector")
     end
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2200,7 +2200,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2224,7 +2224,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
@@ -2247,7 +2247,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}
+    expected = %{<select id="post_written_on_3i" name="post[written_on(3i)]">\n}.dup
     expected << %{<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15" selected="selected">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n}
     expected << "</select>\n"
 
@@ -2265,7 +2265,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="">Year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2285,7 +2285,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}.dup
     expected << %{<option value="">Choose year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2305,7 +2305,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2325,7 +2325,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Date.new(2004, 6, 15)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2345,7 +2345,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2364,7 +2364,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2383,7 +2383,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="1" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="1" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="1" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="1" />\n}
 
@@ -2402,7 +2402,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %(<select id="post_written_on_4i" name="post[written_on(4i)]">\n)
+    expected = %(<select id="post_written_on_4i" name="post[written_on(4i)]">\n).dup
     0.upto(23) { |i| expected << %(<option value="#{sprintf("%02d", i)}"#{' selected="selected"' if i == 15}>#{sprintf("%02d", i)}</option>\n) }
     expected << "</select>\n"
     expected << " : "
@@ -2417,7 +2417,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2440,7 +2440,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2463,7 +2463,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.time_select(:written_on, {}, class: "selector")
     end
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2482,7 +2482,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2509,7 +2509,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2530,7 +2530,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2551,7 +2551,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2572,7 +2572,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2593,7 +2593,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_written_on_1i" disabled="disabled" name="post[written_on(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_written_on_1i" disabled="disabled" name="post[written_on(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_written_on_2i" disabled="disabled" name="post[written_on(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_written_on_3i" disabled="disabled" name="post[written_on(3i)]" value="15" />\n}
 
@@ -2612,7 +2612,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2641,7 +2641,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2707,7 +2707,7 @@ class DateHelperTest < ActionView::TestCase
 
     @post = Post.new
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2742,7 +2742,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.datetime_select(:updated_at, {}, class: "selector")
     end
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option selected="selected" value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n</select>\n}.dup
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]" class="selector">\n<option value="1">January</option>\n<option value="2">February</option>\n<option value="3">March</option>\n<option value="4">April</option>\n<option value="5">May</option>\n<option selected="selected" value="6">June</option>\n<option value="7">July</option>\n<option value="8">August</option>\n<option value="9">September</option>\n<option value="10">October</option>\n<option value="11">November</option>\n<option value="12">December</option>\n</select>\n}
     expected << %{<select id="post_updated_at_3i" name="post[updated_at(3i)]" class="selector">\n<option value="1">1</option>\n<option value="2">2</option>\n<option value="3">3</option>\n<option value="4">4</option>\n<option value="5">5</option>\n<option value="6">6</option>\n<option value="7">7</option>\n<option value="8">8</option>\n<option value="9">9</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option selected="selected" value="15">15</option>\n<option value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n<option value="24">24</option>\n<option value="25">25</option>\n<option value="26">26</option>\n<option value="27">27</option>\n<option value="28">28</option>\n<option value="29">29</option>\n<option value="30">30</option>\n<option value="31">31</option>\n</select>\n}
     expected << %{ &mdash; <select id="post_updated_at_4i" name="post[updated_at(4i)]" class="selector">\n<option value="00">00</option>\n<option value="01">01</option>\n<option value="02">02</option>\n<option value="03">03</option>\n<option value="04">04</option>\n<option value="05">05</option>\n<option value="06">06</option>\n<option value="07">07</option>\n<option value="08">08</option>\n<option value="09">09</option>\n<option value="10">10</option>\n<option value="11">11</option>\n<option value="12">12</option>\n<option value="13">13</option>\n<option value="14">14</option>\n<option value="15">15</option>\n<option selected="selected" value="16">16</option>\n<option value="17">17</option>\n<option value="18">18</option>\n<option value="19">19</option>\n<option value="20">20</option>\n<option value="21">21</option>\n<option value="22">22</option>\n<option value="23">23</option>\n</select>\n}
@@ -2755,7 +2755,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2808,7 +2808,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="">Year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2837,7 +2837,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %{<option value="">Choose year</option>\n<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2866,7 +2866,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2895,7 +2895,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.written_on = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}
+    expected = %{<select id="post_written_on_1i" name="post[written_on(1i)]" class="my-year">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -2921,7 +2921,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_date_select_with_zero_value_and_no_start_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 1) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -2937,7 +2937,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_date_select_with_zero_value_and_no_end_year
-    expected =  %(<select id="date_first_year" name="date[first][year]">\n)
+    expected =  %(<select id="date_first_year" name="date[first][year]">\n).dup
     last_year = Time.now.year + 5
     2003.upto(last_year) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
@@ -2954,7 +2954,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_date_select_with_zero_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -2970,7 +2970,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_date_select_with_nil_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -2986,7 +2986,7 @@ class DateHelperTest < ActionView::TestCase
   end
 
   def test_datetime_select_with_nil_value_and_no_start_and_end_year
-    expected = %(<select id="date_first_year" name="date[first][year]">\n)
+    expected = %(<select id="date_first_year" name="date[first][year]">\n).dup
     (Date.today.year - 5).upto(Date.today.year + 5) { |y| expected << %(<option value="#{y}">#{y}</option>\n) }
     expected << "</select>\n"
 
@@ -3018,7 +3018,7 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
     id = 456
 
-    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3052,7 +3052,7 @@ class DateHelperTest < ActionView::TestCase
       concat f.datetime_select(:updated_at)
     end
 
-    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_456_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3082,7 +3082,7 @@ class DateHelperTest < ActionView::TestCase
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
     id = @post.id
 
-    expected = %{<select id="post_123_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}
+    expected = %{<select id="post_123_updated_at_1i" name="post[#{id}][updated_at(1i)]">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
@@ -3111,7 +3111,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3142,7 +3142,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
     1.upto(12) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 6}>#{Date::MONTHNAMES[i]}</option>\n) }
     expected << "</select>\n"
@@ -3167,7 +3167,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<input type="hidden" id="post_updated_at_2i" name="post[updated_at(2i)]" value="6" />\n}
@@ -3190,7 +3190,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_updated_at_2i" name="post[updated_at(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_updated_at_3i" name="post[updated_at(3i)]" value="1" />\n}
 
@@ -3209,7 +3209,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<input type="hidden" id="post_updated_at_2i" disabled="disabled" name="post[updated_at(2i)]" value="6" />\n}
     expected << %{<input type="hidden" id="post_updated_at_3i" disabled="disabled" name="post[updated_at(3i)]" value="1" />\n}
 
@@ -3228,7 +3228,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3245,7 +3245,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3269,7 +3269,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" disabled="disabled" name="post[updated_at(1i)]">\n}.dup
     1999.upto(2009) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2004}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" disabled="disabled" name="post[updated_at(2i)]">\n}
@@ -3293,7 +3293,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}
+    expected = %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}.dup
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3320,7 +3320,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 15, 16, 35)
 
-    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}
+    expected = %{<input type="hidden" id="post_updated_at_1i" name="post[updated_at(1i)]" value="2004" />\n}.dup
     expected << %{<select id="post_updated_at_3i" name="post[updated_at(3i)]">\n}
     1.upto(31) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 15}>#{i}</option>\n) }
     expected << "</select>\n"
@@ -3345,7 +3345,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     2001.upto(2011) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == 2006}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3372,7 +3372,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     expected << %(<option value=""></option>\n)
     (Time.now.year - 5).upto(Time.now.year + 5) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
     expected << "</select>\n"
@@ -3392,7 +3392,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = nil
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]">\n}.dup
     (Time.now.year - 5).upto(Time.now.year + 5) { |i| expected << %(<option value="#{i}"#{' selected="selected"' if i == Time.now.year}>#{i}</option>\n) }
     expected << "</select>\n"
     expected << %{<select id="post_updated_at_2i" name="post[updated_at(2i)]">\n}
@@ -3419,7 +3419,7 @@ class DateHelperTest < ActionView::TestCase
     @post = Post.new
     @post.updated_at = Time.local(2004, 6, 15, 16, 35)
 
-    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n}
+    expected = %{<select id="post_updated_at_1i" name="post[updated_at(1i)]" class="selector">\n}.dup
     expected << %{<option value="1999">1999</option>\n<option value="2000">2000</option>\n<option value="2001">2001</option>\n<option value="2002">2002</option>\n<option value="2003">2003</option>\n<option value="2004" selected="selected">2004</option>\n<option value="2005">2005</option>\n<option value="2006">2006</option>\n<option value="2007">2007</option>\n<option value="2008">2008</option>\n<option value="2009">2009</option>\n}
     expected << "</select>\n"
 
diff --git a/actionview/test/template/form_helper/form_with_test.rb b/actionview/test/template/form_helper/form_with_test.rb
index d62edf5dd9..cbfe97159d 100644
--- a/actionview/test/template/form_helper/form_with_test.rb
+++ b/actionview/test/template/form_helper/form_with_test.rb
@@ -17,7 +17,7 @@ class FormWithActsLikeFormTagTest < FormWithTest
     method = options[:method]
     skip_enforcing_utf8 = options.fetch(:skip_enforcing_utf8, false)
 
-    "".tap do |txt|
+    "".dup.tap do |txt|
       unless skip_enforcing_utf8
         txt << %{<input name="utf8" type="hidden" value="&#x2713;" />}
       end
@@ -33,7 +33,7 @@ class FormWithActsLikeFormTagTest < FormWithTest
 
     method = method.to_s == "get" ? "get" : "post"
 
-    txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+    txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
     txt << %{ enctype="multipart/form-data"} if enctype
     txt << %{ data-remote="true"} unless local
     txt << %{ class="#{html_class}"} if html_class
@@ -2195,9 +2195,9 @@ class FormWithActsLikeFormForTest < FormWithTest
       method = options[:method]
 
       if options.fetch(:skip_enforcing_utf8, false)
-        txt = ""
+        txt = "".dup
       else
-        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}
+        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
       end
 
       if method && !%w(get post).include?(method.to_s)
@@ -2208,7 +2208,7 @@ class FormWithActsLikeFormForTest < FormWithTest
     end
 
     def form_text(action = "/", id = nil, html_class = nil, local = nil, multipart = nil, method = nil)
-      txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
       txt << %{ enctype="multipart/form-data"} if multipart
       txt << %{ data-remote="true"} unless local
       txt << %{ class="#{html_class}"} if html_class
diff --git a/actionview/test/template/form_helper_test.rb b/actionview/test/template/form_helper_test.rb
index 8c06a6260f..6e67da5555 100644
--- a/actionview/test/template/form_helper_test.rb
+++ b/actionview/test/template/form_helper_test.rb
@@ -3447,9 +3447,9 @@ class FormHelperTest < ActionView::TestCase
       method = options[:method]
 
       if options.fetch(:enforce_utf8, true)
-        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}
+        txt = %{<input name="utf8" type="hidden" value="&#x2713;" />}.dup
       else
-        txt = ""
+        txt = "".dup
       end
 
       if method && !%w(get post).include?(method.to_s)
@@ -3460,7 +3460,7 @@ class FormHelperTest < ActionView::TestCase
     end
 
     def form_text(action = "/", id = nil, html_class = nil, remote = nil, multipart = nil, method = nil)
-      txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+      txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
       txt << %{ enctype="multipart/form-data"} if multipart
       txt << %{ data-remote="true"} if remote
       txt << %{ class="#{html_class}"} if html_class
diff --git a/actionview/test/template/form_tag_helper_test.rb b/actionview/test/template/form_tag_helper_test.rb
index bbcb523771..f4a26e232d 100644
--- a/actionview/test/template/form_tag_helper_test.rb
+++ b/actionview/test/template/form_tag_helper_test.rb
@@ -15,7 +15,7 @@ class FormTagHelperTest < ActionView::TestCase
     method = options[:method]
     enforce_utf8 = options.fetch(:enforce_utf8, true)
 
-    "".tap do |txt|
+    "".dup.tap do |txt|
       if enforce_utf8
         txt << %{<input name="utf8" type="hidden" value="&#x2713;" />}
       end
@@ -31,7 +31,7 @@ class FormTagHelperTest < ActionView::TestCase
 
     method = method.to_s == "get" ? "get" : "post"
 
-    txt =  %{<form accept-charset="UTF-8" action="#{action}"}
+    txt =  %{<form accept-charset="UTF-8" action="#{action}"}.dup
     txt << %{ enctype="multipart/form-data"} if enctype
     txt << %{ data-remote="true"} if remote
     txt << %{ class="#{html_class}"} if html_class
@@ -346,6 +346,12 @@ class FormTagHelperTest < ActionView::TestCase
     assert_dom_equal expected, actual
   end
 
+  def test_text_field_tag_with_ac_parameters
+    actual = text_field_tag "title", ActionController::Parameters.new(key: "value")
+    expected = %(<input id="title" name="title" type="text" value="{&quot;key&quot;=&gt;&quot;value&quot;}" />)
+    assert_dom_equal expected, actual
+  end
+
   def test_text_field_tag_size_string
     actual = text_field_tag "title", "Hello!", "size" => "75"
     expected = %(<input id="title" name="title" size="75" type="text" value="Hello!" />)
diff --git a/actionview/test/template/javascript_helper_test.rb b/actionview/test/template/javascript_helper_test.rb
index fef2625114..43ea8eacc6 100644
--- a/actionview/test/template/javascript_helper_test.rb
+++ b/actionview/test/template/javascript_helper_test.rb
@@ -21,8 +21,8 @@ class JavaScriptHelperTest < ActionView::TestCase
     assert_equal %(This \\"thing\\" is really\\n netos\\'), escape_javascript(%(This "thing" is really\n netos'))
     assert_equal %(backslash\\\\test), escape_javascript(%(backslash\\test))
     assert_equal %(dont <\\/close> tags), escape_javascript(%(dont </close> tags))
-    assert_equal %(unicode &#x2028; newline), escape_javascript(%(unicode \342\200\250 newline).force_encoding(Encoding::UTF_8).encode!)
-    assert_equal %(unicode &#x2029; newline), escape_javascript(%(unicode \342\200\251 newline).force_encoding(Encoding::UTF_8).encode!)
+    assert_equal %(unicode &#x2028; newline), escape_javascript(%(unicode \342\200\250 newline).dup.force_encoding(Encoding::UTF_8).encode!)
+    assert_equal %(unicode &#x2029; newline), escape_javascript(%(unicode \342\200\251 newline).dup.force_encoding(Encoding::UTF_8).encode!)
 
     assert_equal %(dont <\\/close> tags), j(%(dont </close> tags))
   end
diff --git a/actionview/test/template/render_test.rb b/actionview/test/template/render_test.rb
index 3f7e671faf..909aa81833 100644
--- a/actionview/test/template/render_test.rb
+++ b/actionview/test/template/render_test.rb
@@ -440,7 +440,7 @@ module RenderTestCases
   end
 
   CustomHandler = lambda do |template|
-    "@output_buffer = ''\n" \
+    "@output_buffer = ''.dup\n" \
       "@output_buffer << 'source: #{template.source.inspect}'\n"
   end
 
@@ -584,7 +584,7 @@ module RenderTestCases
 
   def test_render_with_passing_couple_extensions_to_one_register_template_handler_function_call
     ActionView::Template.register_template_handler :foo1, :foo2, CustomHandler
-    assert_equal @view.render(inline: "Hello, World!", type: :foo1), @view.render(inline: "Hello, World!", type: :foo2)
+    assert_equal @view.render(inline: "Hello, World!".dup, type: :foo1), @view.render(inline: "Hello, World!".dup, type: :foo2)
   ensure
     ActionView::Template.unregister_template_handler :foo1, :foo2
   end
diff --git a/actionview/test/template/streaming_render_test.rb b/actionview/test/template/streaming_render_test.rb
index 098c2e7551..835f101c00 100644
--- a/actionview/test/template/streaming_render_test.rb
+++ b/actionview/test/template/streaming_render_test.rb
@@ -18,7 +18,7 @@ class FiberedTest < ActiveSupport::TestCase
 
   def buffered_render(options)
     body = render_body(options)
-    string = ""
+    string = "".dup
     body.each do |piece|
       string << piece
     end
diff --git a/actionview/test/template/template_test.rb b/actionview/test/template/template_test.rb
index 0420b2df1d..817e2e4315 100644
--- a/actionview/test/template/template_test.rb
+++ b/actionview/test/template/template_test.rb
@@ -54,7 +54,7 @@ class TestERBTemplate < ActiveSupport::TestCase
   end
 
   def new_template(body = "<%= hello %>", details = { format: :html })
-    ActionView::Template.new(body, "hello template", details.fetch(:handler) { ERBHandler }, { virtual_path: "hello" }.merge!(details))
+    ActionView::Template.new(body.dup, "hello template", details.fetch(:handler) { ERBHandler }, { virtual_path: "hello" }.merge!(details))
   end
 
   def render(locals = {})
diff --git a/actionview/test/template/text_helper_test.rb b/actionview/test/template/text_helper_test.rb
index 52f20b631b..ae923980fa 100644
--- a/actionview/test/template/text_helper_test.rb
+++ b/actionview/test/template/text_helper_test.rb
@@ -12,7 +12,7 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_concat
-    self.output_buffer = "foo"
+    self.output_buffer = "foo".dup
     assert_equal "foobar", concat("bar")
     assert_equal "foobar", output_buffer
   end
@@ -105,8 +105,8 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_truncate_multibyte
-    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding(Encoding::UTF_8),
-      truncate("\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding(Encoding::UTF_8), length: 10)
+    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".dup.force_encoding(Encoding::UTF_8),
+      truncate("\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".dup.force_encoding(Encoding::UTF_8), length: 10)
   end
 
   def test_truncate_does_not_modify_the_options_hash
@@ -326,7 +326,7 @@ class TextHelperTest < ActionView::TestCase
   end
 
   def test_excerpt_with_utf8
-    assert_equal("...\357\254\203ciency could not be...".force_encoding(Encoding::UTF_8), excerpt("That's why e\357\254\203ciency could not be helped".force_encoding(Encoding::UTF_8), "could", radius: 8))
+    assert_equal("...\357\254\203ciency could not be...".dup.force_encoding(Encoding::UTF_8), excerpt("That's why e\357\254\203ciency could not be helped".dup.force_encoding(Encoding::UTF_8), "could", radius: 8))
   end
 
   def test_excerpt_does_not_modify_the_options_hash
diff --git a/actionview/test/template/url_helper_test.rb b/actionview/test/template/url_helper_test.rb
index c5790d29b3..24f9bbec79 100644
--- a/actionview/test/template/url_helper_test.rb
+++ b/actionview/test/template/url_helper_test.rb
@@ -540,7 +540,7 @@ class UrlHelperTest < ActiveSupport::TestCase
 
   def test_current_page_with_escaped_params_with_different_encoding
     @request = request_for_url("/")
-    @request.stub(:path, "/category/administra%c3%a7%c3%a3o".force_encoding(Encoding::ASCII_8BIT)) do
+    @request.stub(:path, "/category/administra%c3%a7%c3%a3o".dup.force_encoding(Encoding::ASCII_8BIT)) do
       assert current_page?(controller: "foo", action: "category", category: "administração")
       assert current_page?("http://www.example.com/category/administra%c3%a7%c3%a3o")
     end
diff --git a/activemodel/test/cases/dirty_test.rb b/activemodel/test/cases/dirty_test.rb
index 56abb17e26..18d2db7edf 100644
--- a/activemodel/test/cases/dirty_test.rb
+++ b/activemodel/test/cases/dirty_test.rb
@@ -97,7 +97,7 @@ class DirtyTest < ActiveModel::TestCase
   end
 
   test "attribute mutation" do
-    @model.instance_variable_set("@name", "Yam")
+    @model.instance_variable_set("@name", "Yam".dup)
     assert !@model.name_changed?
     @model.name.replace("Hadad")
     assert !@model.name_changed?
diff --git a/activemodel/test/cases/type/string_test.rb b/activemodel/test/cases/type/string_test.rb
index 3c9137c055..9c604bcec2 100644
--- a/activemodel/test/cases/type/string_test.rb
+++ b/activemodel/test/cases/type/string_test.rb
@@ -15,7 +15,7 @@ module ActiveModel
       test "cast strings are mutable" do
         type = Type::String.new
 
-        s = "foo"
+        s = "foo".dup
         assert_equal false, type.cast(s).frozen?
         assert_equal false, s.frozen?
 
diff --git a/activerecord/lib/active_record/associations/builder/collection_association.rb b/activerecord/lib/active_record/associations/builder/collection_association.rb
index 4de3371d54..f6e471feca 100644
--- a/activerecord/lib/active_record/associations/builder/collection_association.rb
+++ b/activerecord/lib/active_record/associations/builder/collection_association.rb
@@ -1,6 +1,4 @@
 # frozen_string_literal: true
-# This class is inherited by the has_many and has_many_and_belongs_to_many association classes
-
 require "active_record/associations"
 
 module ActiveRecord::Associations::Builder # :nodoc:
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index f73b0b90cf..8bed7121a8 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -67,6 +67,7 @@ module ActiveRecord
       def reset
         super
         @target = []
+        @association_ids = nil
       end
 
       def find(*args)
@@ -356,7 +357,10 @@ module ActiveRecord
             transaction do
               add_to_target(build_record(attributes)) do |record|
                 yield(record) if block_given?
-                insert_record(record, true, raise) { @_was_loaded = loaded? }
+                insert_record(record, true, raise) {
+                  @_was_loaded = loaded?
+                  @association_ids = nil
+                }
               end
             end
           end
@@ -429,7 +433,12 @@ module ActiveRecord
           records.each do |record|
             raise_on_type_mismatch!(record)
             add_to_target(record) do
-              result &&= insert_record(record, true, raise) { @_was_loaded = loaded? } unless owner.new_record?
+              unless owner.new_record?
+                result &&= insert_record(record, true, raise) {
+                  @_was_loaded = loaded?
+                  @association_ids = nil
+                }
+              end
             end
           end
 
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 575051c45a..011bbaad5c 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -199,8 +199,7 @@ module ActiveRecord
 
         def table_alias_for(reflection, parent, join)
           name = "#{reflection.plural_name}_#{parent.table_name}"
-          name << "_join" if join
-          name
+          join ? "#{name}_join" : name
         end
 
         def walk(left, right)
diff --git a/activerecord/lib/active_record/attribute.rb b/activerecord/lib/active_record/attribute.rb
index 61e8d4d849..7bb0280861 100644
--- a/activerecord/lib/active_record/attribute.rb
+++ b/activerecord/lib/active_record/attribute.rb
@@ -123,7 +123,7 @@ module ActiveRecord
 
     def encode_with(coder)
       coder["name"] = name
-      coder["value_before_type_cast"] = value_before_type_cast if value_before_type_cast
+      coder["value_before_type_cast"] = value_before_type_cast unless value_before_type_cast.nil?
       coder["type"] = type if type
       coder["original_attribute"] = original_attribute if original_attribute
       coder["value"] = value if defined?(@value)
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index fcdef9f033..71a2ac24ea 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -680,7 +680,7 @@ module ActiveRecord
           # this block can't be easily moved into attempt_to_checkout_all_existing_connections's
           # rescue block, because doing so would put it outside of synchronize section, without
           # being in a critical section thread_report might become inaccurate
-          msg = "could not obtain ownership of all database connections in #{checkout_timeout} seconds"
+          msg = "could not obtain ownership of all database connections in #{checkout_timeout} seconds".dup
 
           thread_report = []
           @connections.each do |conn|
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index d36e8d7fdd..c8cf840181 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -52,9 +52,7 @@ module ActiveRecord
 
       # Returns a single value from a record
       def select_value(arel, name = nil, binds = [])
-        if result = select_rows(arel, name, binds).first
-          result.first
-        end
+        single_value_from_rows(select_rows(arel, name, binds))
       end
 
       # Returns an array of the values of the first column in a select:
@@ -69,6 +67,18 @@ module ActiveRecord
         select_all(arel, name, binds).rows
       end
 
+      def query_value(sql, name = nil) # :nodoc:
+        single_value_from_rows(query(sql, name))
+      end
+
+      def query_values(sql, name = nil) # :nodoc:
+        query(sql, name).map(&:first)
+      end
+
+      def query(sql, name = nil) # :nodoc:
+        exec_query(sql, name).rows
+      end
+
       # Executes the SQL statement in the context of this connection and returns
       # the raw result from the connection adapter.
       # Note: depending on your database connector, the result returned by this
@@ -411,7 +421,11 @@ module ActiveRecord
         end
 
         def last_inserted_id(result)
-          row = result.rows.first
+          single_value_from_rows(result.rows)
+        end
+
+        def single_value_from_rows(rows)
+          row = rows.first
           row && row.first
         end
 
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
index 19f0d7558e..a3f9edbc6c 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
@@ -23,7 +23,7 @@ module ActiveRecord
         private
 
           def visit_AlterTable(o)
-            sql = "ALTER TABLE #{quote_table_name(o.name)} "
+            sql = "ALTER TABLE #{quote_table_name(o.name)} ".dup
             sql << o.adds.map { |col| accept col }.join(" ")
             sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(" ")
             sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(" ")
@@ -31,17 +31,17 @@ module ActiveRecord
 
           def visit_ColumnDefinition(o)
             o.sql_type = type_to_sql(o.type, o.options)
-            column_sql = "#{quote_column_name(o.name)} #{o.sql_type}"
+            column_sql = "#{quote_column_name(o.name)} #{o.sql_type}".dup
             add_column_options!(column_sql, column_options(o)) unless o.type == :primary_key
             column_sql
           end
 
           def visit_AddColumnDefinition(o)
-            "ADD #{accept(o.column)}"
+            "ADD #{accept(o.column)}".dup
           end
 
           def visit_TableDefinition(o)
-            create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} "
+            create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} ".dup
 
             statements = o.columns.map { |c| accept c }
             statements << accept(o.primary_keys) if o.primary_keys
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index cf93eb052b..4aed0e214f 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -32,7 +32,7 @@ module ActiveRecord
       # Returns the relation names useable to back Active Record models.
       # For most adapters this means all #tables and #views.
       def data_sources
-        select_values(data_source_sql, "SCHEMA")
+        query_values(data_source_sql, "SCHEMA")
       rescue NotImplementedError
         tables | views
       end
@@ -42,14 +42,14 @@ module ActiveRecord
       #   data_source_exists?(:ebooks)
       #
       def data_source_exists?(name)
-        select_values(data_source_sql(name), "SCHEMA").any? if name.present?
+        query_values(data_source_sql(name), "SCHEMA").any? if name.present?
       rescue NotImplementedError
         data_sources.include?(name.to_s)
       end
 
       # Returns an array of table names defined in the database.
       def tables
-        select_values(data_source_sql(type: "BASE TABLE"), "SCHEMA")
+        query_values(data_source_sql(type: "BASE TABLE"), "SCHEMA")
       end
 
       # Checks to see if the table +table_name+ exists on the database.
@@ -57,14 +57,14 @@ module ActiveRecord
       #   table_exists?(:developers)
       #
       def table_exists?(table_name)
-        select_values(data_source_sql(table_name, type: "BASE TABLE"), "SCHEMA").any? if table_name.present?
+        query_values(data_source_sql(table_name, type: "BASE TABLE"), "SCHEMA").any? if table_name.present?
       rescue NotImplementedError
         tables.include?(table_name.to_s)
       end
 
       # Returns an array of view names defined in the database.
       def views
-        select_values(data_source_sql(type: "VIEW"), "SCHEMA")
+        query_values(data_source_sql(type: "VIEW"), "SCHEMA")
       end
 
       # Checks to see if the view +view_name+ exists on the database.
@@ -72,7 +72,7 @@ module ActiveRecord
       #   view_exists?(:ebooks)
       #
       def view_exists?(view_name)
-        select_values(data_source_sql(view_name, type: "VIEW"), "SCHEMA").any? if view_name.present?
+        query_values(data_source_sql(view_name, type: "VIEW"), "SCHEMA").any? if view_name.present?
       rescue NotImplementedError
         views.include?(view_name.to_s)
       end
@@ -1349,7 +1349,7 @@ module ActiveRecord
           sm_table = quote_table_name(ActiveRecord::SchemaMigration.table_name)
 
           if versions.is_a?(Array)
-            sql = "INSERT INTO #{sm_table} (version) VALUES\n"
+            sql = "INSERT INTO #{sm_table} (version) VALUES\n".dup
             sql << versions.map { |v| "(#{quote(v)})" }.join(",\n")
             sql << ";\n\n"
             sql
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 820803f715..a7d8a80224 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -148,7 +148,7 @@ module ActiveRecord
       # this method must only be called while holding connection pool's mutex
       def lease
         if in_use?
-          msg = "Cannot lease connection, "
+          msg = "Cannot lease connection, ".dup
           if @owner == Thread.current
             msg << "it is already leased by the current thread."
           else
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index 4e29801d3e..d49fa7ed24 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -121,11 +121,11 @@ module ActiveRecord
       end
 
       def get_advisory_lock(lock_name, timeout = 0) # :nodoc:
-        select_value("SELECT GET_LOCK(#{quote(lock_name)}, #{timeout})") == 1
+        query_value("SELECT GET_LOCK(#{quote(lock_name)}, #{timeout})") == 1
       end
 
       def release_advisory_lock(lock_name) # :nodoc:
-        select_value("SELECT RELEASE_LOCK(#{quote(lock_name)})") == 1
+        query_value("SELECT RELEASE_LOCK(#{quote(lock_name)})") == 1
       end
 
       def native_database_types
@@ -133,7 +133,7 @@ module ActiveRecord
       end
 
       def index_algorithms
-        { default: "ALGORITHM = DEFAULT", copy: "ALGORITHM = COPY", inplace: "ALGORITHM = INPLACE" }
+        { default: "ALGORITHM = DEFAULT".dup, copy: "ALGORITHM = COPY".dup, inplace: "ALGORITHM = INPLACE".dup }
       end
 
       # HELPER METHODS ===========================================
@@ -153,7 +153,7 @@ module ActiveRecord
       # REFERENTIAL INTEGRITY ====================================
 
       def disable_referential_integrity #:nodoc:
-        old = select_value("SELECT @@FOREIGN_KEY_CHECKS")
+        old = query_value("SELECT @@FOREIGN_KEY_CHECKS")
 
         begin
           update("SET FOREIGN_KEY_CHECKS = 0")
@@ -268,7 +268,7 @@ module ActiveRecord
       end
 
       def current_database
-        select_value "SELECT DATABASE() as db"
+        query_value("SELECT database()", "SCHEMA")
       end
 
       # Returns the database character set.
@@ -288,7 +288,7 @@ module ActiveRecord
       def table_comment(table_name) # :nodoc:
         scope = quoted_scope(table_name)
 
-        select_value(<<-SQL.strip_heredoc, "SCHEMA")
+        query_value(<<-SQL.strip_heredoc, "SCHEMA")
           SELECT table_comment
           FROM information_schema.tables
           WHERE table_schema = #{scope[:schema]}
@@ -380,7 +380,7 @@ module ActiveRecord
 
       def add_index(table_name, column_name, options = {}) #:nodoc:
         index_name, index_type, index_columns, _, index_algorithm, index_using, comment = add_index_options(table_name, column_name, options)
-        sql = "CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns}) #{index_algorithm}"
+        sql = "CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns}) #{index_algorithm}".dup
         execute add_sql_comment!(sql, comment)
       end
 
@@ -394,7 +394,7 @@ module ActiveRecord
 
         scope = quoted_scope(table_name)
 
-        fk_info = select_all(<<-SQL.strip_heredoc, "SCHEMA")
+        fk_info = exec_query(<<-SQL.strip_heredoc, "SCHEMA")
           SELECT fk.referenced_table_name AS 'to_table',
                  fk.referenced_column_name AS 'primary_key',
                  fk.column_name AS 'column',
@@ -465,13 +465,13 @@ module ActiveRecord
             super
           end
 
-        sql << " unsigned" if unsigned && type != :primary_key
+        sql = "#{sql} unsigned" if unsigned && type != :primary_key
         sql
       end
 
       # SHOW VARIABLES LIKE 'name'
       def show_variable(name)
-        select_value("SELECT @@#{name}", "SCHEMA")
+        query_value("SELECT @@#{name}", "SCHEMA")
       rescue ActiveRecord::StatementInvalid
         nil
       end
@@ -481,7 +481,7 @@ module ActiveRecord
 
         scope = quoted_scope(table_name)
 
-        select_values(<<-SQL.strip_heredoc, "SCHEMA")
+        query_values(<<-SQL.strip_heredoc, "SCHEMA")
           SELECT column_name
           FROM information_schema.key_column_usage
           WHERE constraint_name = 'PRIMARY'
@@ -695,7 +695,7 @@ module ActiveRecord
             auto_increment: column.auto_increment?
           }
 
-          current_type = select_one("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE #{quote(column_name)}", "SCHEMA")["Type"]
+          current_type = exec_query("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE #{quote(column_name)}", "SCHEMA").first["Type"]
           td = create_table_definition(table_name)
           cd = td.new_column_definition(new_column_name, current_type, options)
           schema_creation.accept(ChangeColumnDefinition.new(cd, column.name))
@@ -779,7 +779,7 @@ module ActiveRecord
           # http://dev.mysql.com/doc/refman/5.7/en/set-statement.html#id944430
           # (trailing comma because variable_assignments will always have content)
           if @config[:encoding]
-            encoding = "NAMES #{@config[:encoding]}"
+            encoding = "NAMES #{@config[:encoding]}".dup
             encoding << " COLLATE #{@config[:collation]}" if @config[:collation]
             encoding << ", "
           end
@@ -805,7 +805,7 @@ module ActiveRecord
         end
 
         def create_table_info(table_name) # :nodoc:
-          select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"]
+          exec_query("SHOW CREATE TABLE #{quote_table_name(table_name)}", "SCHEMA").first["Create Table"]
         end
 
         def arel_visitor
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
index 733b4ce734..dcbb6cfa7a 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
@@ -14,6 +14,10 @@ module ActiveRecord
           result
         end
 
+        def query(sql, name = nil) # :nodoc:
+          execute(sql, name).to_a
+        end
+
         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil)
           # make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
index 285aed12e2..a890b54b5e 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_creation.rb
@@ -17,7 +17,7 @@ module ActiveRecord
           end
 
           def visit_ChangeColumnDefinition(o)
-            change_column_sql = "CHANGE #{quote_column_name(o.name)} #{accept(o.column)}"
+            change_column_sql = "CHANGE #{quote_column_name(o.name)} #{accept(o.column)}".dup
             add_column_position!(change_column_sql, column_options(o.column))
           end
 
@@ -64,7 +64,7 @@ module ActiveRecord
 
           def index_in_create(table_name, column_name, options)
             index_name, index_type, index_columns, _, _, index_using, comment = @conn.add_index_options(table_name, column_name, options)
-            add_sql_comment!("#{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})", comment)
+            add_sql_comment!("#{index_type} INDEX #{quote_column_name(index_name)} #{index_using} (#{index_columns})".dup, comment)
           end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
index 1748bceb4e..05f12ef05b 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_dumper.rb
@@ -48,7 +48,7 @@ module ActiveRecord
           def schema_collation(column)
             if column.collation && table_name = column.table_name
               @table_collation_cache ||= {}
-              @table_collation_cache[table_name] ||= select_one("SHOW TABLE STATUS LIKE #{quote(table_name)}")["Collation"]
+              @table_collation_cache[table_name] ||= exec_query("SHOW TABLE STATUS LIKE #{quote(table_name)}", "SCHEMA").first["Collation"]
               column.collation.inspect if column.collation != @table_collation_cache[table_name]
             end
           end
@@ -65,7 +65,7 @@ module ActiveRecord
                     " WHERE table_schema = #{scope[:schema]}" \
                     "   AND table_name = #{scope[:name]}" \
                     "   AND column_name = #{quote(column.name)}"
-              select_value(sql, "SCHEMA").inspect
+              query_value(sql, "SCHEMA").inspect
             end
           end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
index 7d6fa4b60a..470e24a8e7 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
@@ -103,7 +103,7 @@ module ActiveRecord
           def data_source_sql(name = nil, type: nil)
             scope = quoted_scope(name, type: type)
 
-            sql = "SELECT table_name FROM information_schema.tables"
+            sql = "SELECT table_name FROM information_schema.tables".dup
             sql << " WHERE table_schema = #{scope[:schema]}"
             sql << " AND table_name = #{scope[:name]}" if scope[:name]
             sql << " AND table_type = #{scope[:type]}" if scope[:type]
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
index 9ffa81ec59..628f13c44a 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
@@ -79,7 +79,7 @@ module ActiveRecord
 
         private
           def lookup_cast_type(sql_type)
-            super(select_value("SELECT #{quote(sql_type)}::regtype::oid", "SCHEMA").to_i)
+            super(query_value("SELECT #{quote(sql_type)}::regtype::oid", "SCHEMA").to_i)
           end
 
           def _quote(value)
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index b746304c27..14e4929919 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -61,7 +61,7 @@ module ActiveRecord
 
         # Returns true if schema exists.
         def schema_exists?(name)
-          select_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = #{quote(name)}", "SCHEMA").to_i > 0
+          query_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = #{quote(name)}", "SCHEMA").to_i > 0
         end
 
         # Verifies existence of an index with a given name.
@@ -74,7 +74,7 @@ module ActiveRecord
           table = quoted_scope(table_name)
           index = quoted_scope(index_name)
 
-          select_value(<<-SQL, "SCHEMA").to_i > 0
+          query_value(<<-SQL, "SCHEMA").to_i > 0
             SELECT COUNT(*)
             FROM pg_class t
             INNER JOIN pg_index d ON t.oid = d.indrelid
@@ -164,7 +164,7 @@ module ActiveRecord
         def table_comment(table_name) # :nodoc:
           scope = quoted_scope(table_name, type: "BASE TABLE")
           if scope[:name]
-            select_value(<<-SQL.strip_heredoc, "SCHEMA")
+            query_value(<<-SQL.strip_heredoc, "SCHEMA")
               SELECT pg_catalog.obj_description(c.oid, 'pg_class')
               FROM pg_catalog.pg_class c
                 LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
@@ -177,32 +177,32 @@ module ActiveRecord
 
         # Returns the current database name.
         def current_database
-          select_value("SELECT current_database()", "SCHEMA")
+          query_value("SELECT current_database()", "SCHEMA")
         end
 
         # Returns the current schema name.
         def current_schema
-          select_value("SELECT current_schema", "SCHEMA")
+          query_value("SELECT current_schema", "SCHEMA")
         end
 
         # Returns the current database encoding format.
         def encoding
-          select_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA")
+          query_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns the current database collation.
         def collation
-          select_value("SELECT datcollate FROM pg_database WHERE datname = current_database()", "SCHEMA")
+          query_value("SELECT datcollate FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns the current database ctype.
         def ctype
-          select_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA")
+          query_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA")
         end
 
         # Returns an array of schema names.
         def schema_names
-          select_values(<<-SQL, "SCHEMA")
+          query_values(<<-SQL, "SCHEMA")
             SELECT nspname
               FROM pg_namespace
              WHERE nspname !~ '^pg_.*'
@@ -235,12 +235,12 @@ module ActiveRecord
 
         # Returns the active schema search path.
         def schema_search_path
-          @schema_search_path ||= select_value("SHOW search_path", "SCHEMA")
+          @schema_search_path ||= query_value("SHOW search_path", "SCHEMA")
         end
 
         # Returns the current client message level.
         def client_min_messages
-          select_value("SHOW client_min_messages", "SCHEMA")
+          query_value("SHOW client_min_messages", "SCHEMA")
         end
 
         # Set the client message level.
@@ -258,7 +258,7 @@ module ActiveRecord
         end
 
         def serial_sequence(table, column)
-          select_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA")
+          query_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA")
         end
 
         # Sets the sequence of a table's primary key to the specified value.
@@ -269,7 +269,7 @@ module ActiveRecord
             if sequence
               quoted_sequence = quote_table_name(sequence)
 
-              select_value("SELECT setval(#{quote(quoted_sequence)}, #{value})", "SCHEMA")
+              query_value("SELECT setval(#{quote(quoted_sequence)}, #{value})", "SCHEMA")
             else
               @logger.warn "#{table} has primary key #{pk} with no default sequence." if @logger
             end
@@ -291,18 +291,16 @@ module ActiveRecord
 
           if pk && sequence
             quoted_sequence = quote_table_name(sequence)
-            max_pk = select_value("select MAX(#{quote_column_name pk}) from #{quote_table_name(table)}")
+            max_pk = query_value("SELECT MAX(#{quote_column_name pk}) FROM #{quote_table_name(table)}", "SCHEMA")
             if max_pk.nil?
               if postgresql_version >= 100000
-                minvalue = select_value("SELECT seqmin from pg_sequence where seqrelid = #{quote(quoted_sequence)}::regclass")
+                minvalue = query_value("SELECT seqmin FROM pg_sequence WHERE seqrelid = #{quote(quoted_sequence)}::regclass", "SCHEMA")
               else
-                minvalue = select_value("SELECT min_value FROM #{quoted_sequence}")
+                minvalue = query_value("SELECT min_value FROM #{quoted_sequence}", "SCHEMA")
               end
             end
 
-            select_value(<<-end_sql, "SCHEMA")
-              SELECT setval(#{quote(quoted_sequence)}, #{max_pk ? max_pk : minvalue}, #{max_pk ? true : false})
-            end_sql
+            query_value("SELECT setval(#{quote(quoted_sequence)}, #{max_pk ? max_pk : minvalue}, #{max_pk ? true : false})", "SCHEMA")
           end
         end
 
@@ -361,7 +359,7 @@ module ActiveRecord
         end
 
         def primary_keys(table_name) # :nodoc:
-          select_values(<<-SQL.strip_heredoc, "SCHEMA")
+          query_values(<<-SQL.strip_heredoc, "SCHEMA")
             SELECT a.attname
               FROM (
                      SELECT indrelid, indkey, generate_subscripts(indkey, 1) idx
@@ -409,7 +407,7 @@ module ActiveRecord
           quoted_table_name = quote_table_name(table_name)
           quoted_column_name = quote_column_name(column_name)
           sql_type = type_to_sql(type, options)
-          sql = "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quoted_column_name} TYPE #{sql_type}"
+          sql = "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quoted_column_name} TYPE #{sql_type}".dup
           if options[:collation]
             sql << " COLLATE \"#{options[:collation]}\""
           end
@@ -512,7 +510,7 @@ module ActiveRecord
 
         def foreign_keys(table_name)
           scope = quoted_scope(table_name)
-          fk_info = select_all(<<-SQL.strip_heredoc, "SCHEMA")
+          fk_info = exec_query(<<-SQL.strip_heredoc, "SCHEMA")
             SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete
             FROM pg_constraint c
             JOIN pg_class t1 ON c.conrelid = t1.oid
@@ -569,7 +567,7 @@ module ActiveRecord
               super
             end
 
-          sql << "[]" if array && type != :primary_key
+          sql = "#{sql}[]" if array && type != :primary_key
           sql
         end
 
@@ -638,7 +636,7 @@ module ActiveRecord
             scope = quoted_scope(name, type: type)
             scope[:type] ||= "'r','v','m'" # (r)elation/table, (v)iew, (m)aterialized view
 
-            sql = "SELECT c.relname FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace"
+            sql = "SELECT c.relname FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace".dup
             sql << " WHERE n.nspname = #{scope[:schema]}"
             sql << " AND c.relname = #{scope[:name]}" if scope[:name]
             sql << " AND c.relkind IN (#{scope[:type]})"
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index edf313f49d..38285366b4 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -313,14 +313,14 @@ module ActiveRecord
         unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
           raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
         end
-        select_value("SELECT pg_try_advisory_lock(#{lock_id});")
+        query_value("SELECT pg_try_advisory_lock(#{lock_id})")
       end
 
       def release_advisory_lock(lock_id) # :nodoc:
         unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
           raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
         end
-        select_value("SELECT pg_advisory_unlock(#{lock_id})")
+        query_value("SELECT pg_advisory_unlock(#{lock_id})")
       end
 
       def enable_extension(name)
@@ -337,15 +337,14 @@ module ActiveRecord
 
       def extension_enabled?(name)
         if supports_extensions?
-          res = exec_query "SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled",
-            "SCHEMA"
+          res = exec_query("SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled", "SCHEMA")
           res.cast_values.first
         end
       end
 
       def extensions
         if supports_extensions?
-          exec_query("SELECT extname from pg_extension", "SCHEMA").cast_values
+          exec_query("SELECT extname FROM pg_extension", "SCHEMA").cast_values
         else
           super
         end
@@ -353,14 +352,14 @@ module ActiveRecord
 
       # Returns the configured supported identifier length supported by PostgreSQL
       def table_alias_length
-        @max_identifier_length ||= select_value("SHOW max_identifier_length", "SCHEMA").to_i
+        @max_identifier_length ||= query_value("SHOW max_identifier_length", "SCHEMA").to_i
       end
       alias index_name_length table_alias_length
 
       # Set the authorized user for this session
       def session_auth=(user)
         clear_cache!
-        exec_query "SET SESSION AUTHORIZATION #{user}"
+        execute("SET SESSION AUTHORIZATION #{user}")
       end
 
       def use_insert_returning?
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb
index 9c10970d34..c268fc173b 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb
@@ -12,7 +12,7 @@ module ActiveRecord
           end
 
           exec_query("PRAGMA index_list(#{quote_table_name(table_name)})", "SCHEMA").map do |row|
-            index_sql = select_value(<<-SQL, "SCHEMA")
+            index_sql = query_value(<<-SQL, "SCHEMA")
               SELECT sql
               FROM sqlite_master
               WHERE name = #{quote(row['name'])} AND type = 'index'
@@ -68,7 +68,7 @@ module ActiveRecord
             scope = quoted_scope(name, type: type)
             scope[:type] ||= "'table','view'"
 
-            sql = "SELECT name FROM sqlite_master WHERE name <> 'sqlite_sequence'"
+            sql = "SELECT name FROM sqlite_master WHERE name <> 'sqlite_sequence'".dup
             sql << " AND name = #{scope[:name]}" if scope[:name]
             sql << " AND type IN (#{scope[:type]})"
             sql
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index c4cbdb588c..31d5b5946e 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -170,7 +170,7 @@ module ActiveRecord
       # REFERENTIAL INTEGRITY ====================================
 
       def disable_referential_integrity # :nodoc:
-        old = select_value("PRAGMA foreign_keys")
+        old = query_value("PRAGMA foreign_keys")
 
         begin
           execute("PRAGMA foreign_keys = OFF")
@@ -338,7 +338,7 @@ module ActiveRecord
       alias :add_belongs_to :add_reference
 
       def foreign_keys(table_name)
-        fk_info = select_all("PRAGMA foreign_key_list(#{quote(table_name)})", "SCHEMA")
+        fk_info = exec_query("PRAGMA foreign_key_list(#{quote(table_name)})", "SCHEMA")
         fk_info.map do |row|
           options = {
             column: row["from"],
@@ -444,7 +444,7 @@ module ActiveRecord
         end
 
         def sqlite_version
-          @sqlite_version ||= SQLite3Adapter::Version.new(select_value("SELECT sqlite_version(*)"))
+          @sqlite_version ||= SQLite3Adapter::Version.new(query_value("SELECT sqlite_version(*)"))
         end
 
         def translate_exception(exception, message)
diff --git a/activerecord/lib/active_record/explain.rb b/activerecord/lib/active_record/explain.rb
index c6a9e2a67c..31449e810e 100644
--- a/activerecord/lib/active_record/explain.rb
+++ b/activerecord/lib/active_record/explain.rb
@@ -17,7 +17,7 @@ module ActiveRecord
     # Returns a formatted string ready to be logged.
     def exec_explain(queries) # :nodoc:
       str = queries.map do |sql, binds|
-        msg = "EXPLAIN for: #{sql}"
+        msg = "EXPLAIN for: #{sql}".dup
         unless binds.empty?
           msg << " "
           msg << binds.map { |attr| render_bind(attr) }.inspect
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index f83842958c..1b1403b1a5 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -158,7 +158,7 @@ module ActiveRecord
 
   class ProtectedEnvironmentError < ActiveRecordError #:nodoc:
     def initialize(env = "production")
-      msg = "You are attempting to run a destructive action against your '#{env}' database.\n"
+      msg = "You are attempting to run a destructive action against your '#{env}' database.\n".dup
       msg << "If you are sure you want to continue, run the same command with the environment variable:\n"
       msg << "DISABLE_DATABASE_ENVIRONMENT_CHECK=1"
       super(msg)
@@ -167,7 +167,7 @@ module ActiveRecord
 
   class EnvironmentMismatchError < ActiveRecordError
     def initialize(current: nil, stored: nil)
-      msg =  "You are attempting to modify a database that was last run in `#{ stored }` environment.\n"
+      msg =  "You are attempting to modify a database that was last run in `#{ stored }` environment.\n".dup
       msg << "You are running in `#{ current }` environment. "
       msg << "If you are sure you want to continue, first set the environment using:\n\n"
       msg << "        bin/rails db:environment:set"
@@ -1240,7 +1240,7 @@ module ActiveRecord
           record_version_state_after_migrating(migration.version)
         end
       rescue => e
-        msg = "An error has occurred, "
+        msg = "An error has occurred, ".dup
         msg << "this and " if use_transaction?(migration)
         msg << "all later migrations canceled:\n\n#{e}"
         raise StandardError, msg, e.backtrace
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index be76256186..6318bff685 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -593,7 +593,7 @@ module ActiveRecord
       end
 
       VALID_AUTOMATIC_INVERSE_MACROS = [:has_many, :has_one, :belongs_to]
-      INVALID_AUTOMATIC_INVERSE_OPTIONS = [:conditions, :through, :polymorphic, :foreign_key]
+      INVALID_AUTOMATIC_INVERSE_OPTIONS = [:conditions, :through, :foreign_key]
 
       def add_as_source(seed)
         seed
@@ -664,9 +664,8 @@ module ActiveRecord
         # us from being able to guess the inverse automatically. First, the
         # <tt>inverse_of</tt> option cannot be set to false. Second, we must
         # have <tt>has_many</tt>, <tt>has_one</tt>, <tt>belongs_to</tt> associations.
-        # Third, we must not have options such as <tt>:polymorphic</tt> or
-        # <tt>:foreign_key</tt> which prevent us from correctly guessing the
-        # inverse association.
+        # Third, we must not have options such as <tt>:foreign_key</tt>
+        # which prevent us from correctly guessing the inverse association.
         #
         # Anything with a scope can additionally ruin our attempt at finding an
         # inverse, so we exclude reflections with scopes.
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index caa65af50c..88c68685bc 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -335,14 +335,14 @@ module ActiveRecord
       name = @klass.name
 
       if ids.nil?
-        error = "Couldn't find #{name}"
+        error = "Couldn't find #{name}".dup
         error << " with#{conditions}" if conditions
         raise RecordNotFound.new(error, name)
       elsif Array(ids).size == 1
         error = "Couldn't find #{name} with '#{key}'=#{ids}#{conditions}"
         raise RecordNotFound.new(error, name, key, ids)
       else
-        error = "Couldn't find all #{name.pluralize} with '#{key}': "
+        error = "Couldn't find all #{name.pluralize} with '#{key}': ".dup
         error << "(#{ids.join(", ")})#{conditions} (found #{result_size} results, but was looking for #{expected_size})"
 
         raise RecordNotFound.new(error, name, primary_key, ids)
diff --git a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
index 447bf09a4f..730d077ecf 100644
--- a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
@@ -152,7 +152,7 @@ IDENTIFIED BY '#{configuration['password']}' WITH GRANT OPTION;
         end
 
         def run_cmd_error(cmd, args, action)
-          msg = "failed to execute: `#{cmd}`\n"
+          msg = "failed to execute: `#{cmd}`\n".dup
           msg << "Please check the output above for any errors and make sure that `#{cmd}` is installed in your PATH and has proper permissions.\n\n"
           msg
         end
diff --git a/activerecord/test/cases/adapters/postgresql/bytea_test.rb b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
index 7cb5c2442c..39d76de770 100644
--- a/activerecord/test/cases/adapters/postgresql/bytea_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
@@ -48,7 +48,7 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_type_cast_binary_value
-    data = "\u001F\x8B".force_encoding("BINARY")
+    data = "\u001F\x8B".dup.force_encoding("BINARY")
     assert_equal(data, @type.deserialize(data))
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/money_test.rb b/activerecord/test/cases/adapters/postgresql/money_test.rb
index 530aeb0c29..f5c50a80c2 100644
--- a/activerecord/test/cases/adapters/postgresql/money_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/money_test.rb
@@ -48,10 +48,10 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
 
   def test_money_type_cast
     type = PostgresqlMoney.type_for_attribute("wealth")
-    assert_equal(12345678.12, type.cast("$12,345,678.12"))
-    assert_equal(12345678.12, type.cast("$12.345.678,12"))
-    assert_equal(-1.15, type.cast("-$1.15"))
-    assert_equal(-2.25, type.cast("($2.25)"))
+    assert_equal(12345678.12, type.cast("$12,345,678.12".dup))
+    assert_equal(12345678.12, type.cast("$12.345.678,12".dup))
+    assert_equal(-1.15, type.cast("-$1.15".dup))
+    assert_equal(-2.25, type.cast("($2.25)".dup))
   end
 
   def test_schema_dumping
@@ -61,7 +61,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_create_and_update_money
-    money = PostgresqlMoney.create(wealth: "987.65")
+    money = PostgresqlMoney.create(wealth: "987.65".dup)
     assert_equal 987.65, money.wealth
 
     new_value = BigDecimal.new("123.45")
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index 7adba54836..bc6605682c 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -166,7 +166,7 @@ module ActiveRecord
             data binary
           )
         eosql
-        str = "\x80".force_encoding("ASCII-8BIT")
+        str = "\x80".dup.force_encoding("ASCII-8BIT")
         binary = DualEncoding.new name: "いただきます！", data: str
         binary.save!
         assert_equal str, binary.data
@@ -175,7 +175,7 @@ module ActiveRecord
       end
 
       def test_type_cast_should_not_mutate_encoding
-        name = "hello".force_encoding(Encoding::ASCII_8BIT)
+        name = "hello".dup.force_encoding(Encoding::ASCII_8BIT)
         Owner.create(name: name)
         assert_equal Encoding::ASCII_8BIT, name.encoding
       ensure
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 07354a2379..5ad1e2aecc 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -242,6 +242,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal "defaulty", bulb.name
   end
 
+  def test_build_from_association_sets_inverse_instance
+    car = Car.new(name: "honda")
+
+    bulb = car.bulbs.build
+    assert_equal car, bulb.car
+  end
+
   def test_do_not_call_callbacks_for_delete_all
     car = Car.create(name: "honda")
     car.funky_bulbs.create!
@@ -2176,6 +2183,13 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal "Post", tagging.taggable_type
   end
 
+  def test_build_from_polymorphic_association_sets_inverse_instance
+    post = Post.new
+    tagging = post.taggings.build
+
+    assert_equal post, tagging.taggable
+  end
+
   def test_dont_call_save_callbacks_twice_on_has_many
     firm = companies(:first_firm)
     contract = firm.contracts.create!
@@ -2545,6 +2559,11 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
     assert_equal [bulb.id], car.bulb_ids
     assert_no_queries { car.bulb_ids }
+
+    bulb2 = car.bulbs.create!
+
+    assert_equal [bulb.id, bulb2.id], car.bulb_ids
+    assert_no_queries { car.bulb_ids }
   end
 
   def test_loading_association_in_validate_callback_doesnt_affect_persistence
diff --git a/activerecord/test/cases/associations/inverse_associations_test.rb b/activerecord/test/cases/associations/inverse_associations_test.rb
index d8f7d3b21c..95ba6bdf8a 100644
--- a/activerecord/test/cases/associations/inverse_associations_test.rb
+++ b/activerecord/test/cases/associations/inverse_associations_test.rb
@@ -117,15 +117,11 @@ class AutomaticInverseFindingTests < ActiveRecord::TestCase
     assert !club_reflection.has_inverse?, "A has_many_through association should not find an inverse automatically"
   end
 
-  def test_polymorphic_relationships_should_still_not_have_inverses_when_non_polymorphic_relationship_has_the_same_name
+  def test_polymorphic_has_one_should_find_inverse_automatically
     man_reflection = Man.reflect_on_association(:polymorphic_face_without_inverse)
-    face_reflection = Face.reflect_on_association(:man)
-
-    assert_respond_to face_reflection, :has_inverse?
-    assert face_reflection.has_inverse?, "For this test, the non-polymorphic association must have an inverse"
 
     assert_respond_to man_reflection, :has_inverse?
-    assert !man_reflection.has_inverse?, "The target of a polymorphic association should not find an inverse automatically"
+    assert man_reflection.has_inverse?
   end
 end
 
diff --git a/activerecord/test/cases/attribute_test.rb b/activerecord/test/cases/attribute_test.rb
index 0271ed5fb9..ed9fb1b57b 100644
--- a/activerecord/test/cases/attribute_test.rb
+++ b/activerecord/test/cases/attribute_test.rb
@@ -77,7 +77,7 @@ module ActiveRecord
     end
 
     test "duping dups the value" do
-      @type.expect(:deserialize, "type cast", ["a value"])
+      @type.expect(:deserialize, "type cast".dup, ["a value"])
       attribute = Attribute.from_database(nil, "a value", @type)
 
       value_from_orig = attribute.value
@@ -245,7 +245,7 @@ module ActiveRecord
     end
 
     test "with_type preserves mutations" do
-      attribute = Attribute.from_database(:foo, "", Type::Value.new)
+      attribute = Attribute.from_database(:foo, "".dup, Type::Value.new)
       attribute.value << "1"
 
       assert_equal 1, attribute.with_type(Type::Integer.new).value
diff --git a/activerecord/test/cases/batches_test.rb b/activerecord/test/cases/batches_test.rb
index 1f666a5d39..beae679542 100644
--- a/activerecord/test/cases/batches_test.rb
+++ b/activerecord/test/cases/batches_test.rb
@@ -153,7 +153,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_find_in_batches_should_not_use_records_after_yielding_them_in_case_original_array_is_modified
-    not_a_post = "not a post"
+    not_a_post = "not a post".dup
     def not_a_post.id; end
     not_a_post.stub(:id, -> { raise StandardError.new("not_a_post had #id called on it") }) do
       assert_nothing_raised do
@@ -418,7 +418,7 @@ class EachTest < ActiveRecord::TestCase
   end
 
   def test_in_batches_should_not_use_records_after_yielding_them_in_case_original_array_is_modified
-    not_a_post = "not a post"
+    not_a_post = "not a post".dup
     def not_a_post.id
       raise StandardError.new("not_a_post had #id called on it")
     end
diff --git a/activerecord/test/cases/binary_test.rb b/activerecord/test/cases/binary_test.rb
index 324a74492c..89301563f9 100644
--- a/activerecord/test/cases/binary_test.rb
+++ b/activerecord/test/cases/binary_test.rb
@@ -11,7 +11,7 @@ unless current_adapter?(:DB2Adapter)
     FIXTURES = %w(flowers.jpg example.log test.txt)
 
     def test_mixed_encoding
-      str = "\x80"
+      str = "\x80".dup
       str.force_encoding("ASCII-8BIT")
 
       binary = Binary.new name: "いただきます！", data: str
diff --git a/activerecord/test/cases/core_test.rb b/activerecord/test/cases/core_test.rb
index 0345608191..5cf962c39d 100644
--- a/activerecord/test/cases/core_test.rb
+++ b/activerecord/test/cases/core_test.rb
@@ -36,7 +36,7 @@ class CoreTest < ActiveRecord::TestCase
 
   def test_pretty_print_new
     topic = Topic.new
-    actual = ""
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = <<-PRETTY.strip_heredoc
     #<Topic:0xXXXXXX
@@ -65,7 +65,7 @@ class CoreTest < ActiveRecord::TestCase
 
   def test_pretty_print_persisted
     topic = topics(:first)
-    actual = ""
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = <<-PRETTY.strip_heredoc
     #<Topic:0x\\w+
@@ -93,7 +93,7 @@ class CoreTest < ActiveRecord::TestCase
 
   def test_pretty_print_uninitialized
     topic = Topic.allocate
-    actual = ""
+    actual = "".dup
     PP.pp(topic, StringIO.new(actual))
     expected = "#<Topic:XXXXXX not initialized>\n"
     assert actual.start_with?(expected.split("XXXXXX").first)
@@ -106,7 +106,7 @@ class CoreTest < ActiveRecord::TestCase
         "inspecting topic"
       end
     end
-    actual = ""
+    actual = "".dup
     PP.pp(subtopic.new, StringIO.new(actual))
     assert_equal "inspecting topic\n", actual
   end
diff --git a/activerecord/test/cases/yaml_serialization_test.rb b/activerecord/test/cases/yaml_serialization_test.rb
index 6b9f632f22..1b67e150f3 100644
--- a/activerecord/test/cases/yaml_serialization_test.rb
+++ b/activerecord/test/cases/yaml_serialization_test.rb
@@ -120,6 +120,14 @@ class YamlSerializationTest < ActiveRecord::TestCase
     assert_equal author.changes, dumped.changes
   end
 
+  def test_yaml_encoding_keeps_false_values
+    topic = Topic.first
+    topic.approved = false
+    dumped = YAML.load(YAML.dump(topic))
+
+    assert_equal false, dumped.approved
+  end
+
   private
 
     def yaml_fixture(file_name)
diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb
index 729119d87a..1a037c1b07 100644
--- a/activesupport/lib/active_support/cache.rb
+++ b/activesupport/lib/active_support/cache.rb
@@ -76,7 +76,7 @@ module ActiveSupport
       #
       # The +key+ argument can also respond to +cache_key+ or +to_param+.
       def expand_cache_key(key, namespace = nil)
-        expanded_cache_key = namespace ? "#{namespace}/" : ""
+        expanded_cache_key = (namespace ? "#{namespace}/" : "").dup
 
         if prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
           expanded_cache_key << "#{prefix}/"
diff --git a/activesupport/lib/active_support/deprecation.rb b/activesupport/lib/active_support/deprecation.rb
index 17b0ee1943..49a9696955 100644
--- a/activesupport/lib/active_support/deprecation.rb
+++ b/activesupport/lib/active_support/deprecation.rb
@@ -34,7 +34,7 @@ module ActiveSupport
     # and the second is a library name.
     #
     #   ActiveSupport::Deprecation.new('2.0', 'MyLibrary')
-    def initialize(deprecation_horizon = "5.3", gem_name = "Rails")
+    def initialize(deprecation_horizon = "6.0", gem_name = "Rails")
       self.gem_name = gem_name
       self.deprecation_horizon = deprecation_horizon
       # By default, warnings are not silenced and debugging is off.
diff --git a/activesupport/lib/active_support/duration/iso8601_serializer.rb b/activesupport/lib/active_support/duration/iso8601_serializer.rb
index 71d2cf91f4..71504fc6cc 100644
--- a/activesupport/lib/active_support/duration/iso8601_serializer.rb
+++ b/activesupport/lib/active_support/duration/iso8601_serializer.rb
@@ -16,12 +16,12 @@ module ActiveSupport
         parts, sign = normalize
         return "PT0S".freeze if parts.empty?
 
-        output = "P"
+        output = "P".dup
         output << "#{parts[:years]}Y"   if parts.key?(:years)
         output << "#{parts[:months]}M"  if parts.key?(:months)
         output << "#{parts[:weeks]}W"   if parts.key?(:weeks)
         output << "#{parts[:days]}D"    if parts.key?(:days)
-        time = ""
+        time = "".dup
         time << "#{parts[:hours]}H"     if parts.key?(:hours)
         time << "#{parts[:minutes]}M"   if parts.key?(:minutes)
         if parts.key?(:seconds)
diff --git a/activesupport/lib/active_support/message_encryptor.rb b/activesupport/lib/active_support/message_encryptor.rb
index c03d8a22d5..84e5508c74 100644
--- a/activesupport/lib/active_support/message_encryptor.rb
+++ b/activesupport/lib/active_support/message_encryptor.rb
@@ -115,7 +115,7 @@ module ActiveSupport
         encrypted_data << cipher.final
 
         blob = "#{::Base64.strict_encode64 encrypted_data}--#{::Base64.strict_encode64 iv}"
-        blob << "--#{::Base64.strict_encode64 cipher.auth_tag}" if aead_mode?
+        blob = "#{blob}--#{::Base64.strict_encode64 cipher.auth_tag}" if aead_mode?
         blob
       end
 
diff --git a/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb b/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
index a60e216433..e1f2fec55b 100644
--- a/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_phone_converter.rb
@@ -3,7 +3,7 @@ module ActiveSupport
   module NumberHelper
     class NumberToPhoneConverter < NumberConverter #:nodoc:
       def convert
-        str = country_code(opts[:country_code])
+        str = country_code(opts[:country_code]).dup
         str << convert_to_phone_number(number.to_s.strip)
         str << phone_ext(opts[:extension])
       end
diff --git a/activesupport/lib/active_support/xml_mini/libxml.rb b/activesupport/lib/active_support/xml_mini/libxml.rb
index 0d3eae25cc..9d2c91e281 100644
--- a/activesupport/lib/active_support/xml_mini/libxml.rb
+++ b/activesupport/lib/active_support/xml_mini/libxml.rb
@@ -54,7 +54,7 @@ module LibXML #:nodoc:
           if c.element?
             c.to_hash(node_hash)
           elsif c.text? || c.cdata?
-            node_hash[CONTENT_ROOT] ||= ""
+            node_hash[CONTENT_ROOT] ||= "".dup
             node_hash[CONTENT_ROOT] << c.content
           end
         end
diff --git a/activesupport/lib/active_support/xml_mini/libxmlsax.rb b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
index fa2be15bea..0ce297427e 100644
--- a/activesupport/lib/active_support/xml_mini/libxmlsax.rb
+++ b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
@@ -22,7 +22,7 @@ module ActiveSupport
       end
 
       def on_start_document
-        @hash = { CONTENT_KEY => "" }
+        @hash = { CONTENT_KEY => "".dup }
         @hash_stack = [@hash]
       end
 
@@ -32,7 +32,7 @@ module ActiveSupport
       end
 
       def on_start_element(name, attrs = {})
-        new_hash = { CONTENT_KEY => "" }.merge!(attrs)
+        new_hash = { CONTENT_KEY => "".dup }.merge!(attrs)
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
diff --git a/activesupport/lib/active_support/xml_mini/nokogiri.rb b/activesupport/lib/active_support/xml_mini/nokogiri.rb
index 6578cc2b4e..1d1bffe540 100644
--- a/activesupport/lib/active_support/xml_mini/nokogiri.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogiri.rb
@@ -58,7 +58,7 @@ module ActiveSupport
             if c.element?
               c.to_hash(node_hash)
             elsif c.text? || c.cdata?
-              node_hash[CONTENT_ROOT] ||= ""
+              node_hash[CONTENT_ROOT] ||= "".dup
               node_hash[CONTENT_ROOT] << c.content
             end
           end
diff --git a/activesupport/lib/active_support/xml_mini/nokogirisax.rb b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
index e754ec08a3..f575e2829c 100644
--- a/activesupport/lib/active_support/xml_mini/nokogirisax.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
@@ -38,7 +38,7 @@ module ActiveSupport
       end
 
       def start_element(name, attrs = [])
-        new_hash = { CONTENT_KEY => "" }.merge!(Hash[attrs])
+        new_hash = { CONTENT_KEY => "".dup }.merge!(Hash[attrs])
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
diff --git a/activesupport/lib/active_support/xml_mini/rexml.rb b/activesupport/lib/active_support/xml_mini/rexml.rb
index ced362c295..49ab277f29 100644
--- a/activesupport/lib/active_support/xml_mini/rexml.rb
+++ b/activesupport/lib/active_support/xml_mini/rexml.rb
@@ -75,7 +75,7 @@ module ActiveSupport
           hash
         else
           # must use value to prevent double-escaping
-          texts = ""
+          texts = "".dup
           element.texts.each { |t| texts << t.value }
           merge!(hash, CONTENT_KEY, texts)
         end
diff --git a/activesupport/test/cache/behaviors/cache_store_behavior.rb b/activesupport/test/cache/behaviors/cache_store_behavior.rb
index 4e86622199..32373644cf 100644
--- a/activesupport/test/cache/behaviors/cache_store_behavior.rb
+++ b/activesupport/test/cache/behaviors/cache_store_behavior.rb
@@ -197,7 +197,7 @@ module CacheStoreBehavior
   end
 
   def test_original_store_objects_should_not_be_immutable
-    bar = "bar"
+    bar = "bar".dup
     @cache.write("foo", bar)
     assert_nothing_raised { bar.gsub!(/.*/, "baz") }
   end
@@ -286,7 +286,7 @@ module CacheStoreBehavior
   end
 
   def test_really_long_keys
-    key = ""
+    key = "".dup
     900.times { key << "x" }
     assert @cache.write(key, "bar")
     assert_equal "bar", @cache.read(key)
diff --git a/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb b/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb
index 9fab1f966d..361903ab82 100644
--- a/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb
+++ b/activesupport/test/cache/behaviors/encoded_key_cache_behavior.rb
@@ -5,7 +5,7 @@
 module EncodedKeyCacheBehavior
   Encoding.list.each do |encoding|
     define_method "test_#{encoding.name.underscore}_encoded_values" do
-      key = "foo".force_encoding(encoding)
+      key = "foo".dup.force_encoding(encoding)
       assert @cache.write(key, "1", raw: true)
       assert_equal "1", @cache.read(key)
       assert_equal "1", @cache.fetch(key)
@@ -17,7 +17,7 @@ module EncodedKeyCacheBehavior
   end
 
   def test_common_utf8_values
-    key = "\xC3\xBCmlaut".force_encoding(Encoding::UTF_8)
+    key = "\xC3\xBCmlaut".dup.force_encoding(Encoding::UTF_8)
     assert @cache.write(key, "1", raw: true)
     assert_equal "1", @cache.read(key)
     assert_equal "1", @cache.fetch(key)
@@ -28,7 +28,7 @@ module EncodedKeyCacheBehavior
   end
 
   def test_retains_encoding
-    key = "\xC3\xBCmlaut".force_encoding(Encoding::UTF_8)
+    key = "\xC3\xBCmlaut".dup.force_encoding(Encoding::UTF_8)
     assert @cache.write(key, "1", raw: true)
     assert_equal Encoding::UTF_8, key.encoding
   end
diff --git a/activesupport/test/cache/cache_key_test.rb b/activesupport/test/cache/cache_key_test.rb
index 2111624153..19c40d44d6 100644
--- a/activesupport/test/cache/cache_key_test.rb
+++ b/activesupport/test/cache/cache_key_test.rb
@@ -46,7 +46,7 @@ class CacheKeyTest < ActiveSupport::TestCase
   end
 
   def test_expand_cache_key_respond_to_cache_key
-    key = "foo"
+    key = "foo".dup
     def key.cache_key
       :foo_key
     end
@@ -54,7 +54,7 @@ class CacheKeyTest < ActiveSupport::TestCase
   end
 
   def test_expand_cache_key_array_with_something_that_responds_to_cache_key
-    key = "foo"
+    key = "foo".dup
     def key.cache_key
       :foo_key
     end
diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index ed5854b8ff..defec8bba0 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -234,7 +234,7 @@ class StringInflectionsTest < ActiveSupport::TestCase
 
   def test_string_squish
     original = %{\u205f\u3000 A string surrounded by various unicode spaces,
-      with tabs(\t\t), newlines(\n\n), unicode nextlines(\u0085\u0085) and many spaces(  ). \u00a0\u2007}
+      with tabs(\t\t), newlines(\n\n), unicode nextlines(\u0085\u0085) and many spaces(  ). \u00a0\u2007}.dup
 
     expected = "A string surrounded by various unicode spaces, " \
       "with tabs( ), newlines( ), unicode nextlines( ) and many spaces( )."
@@ -304,8 +304,8 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_truncate_multibyte
-    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding(Encoding::UTF_8),
-      "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding(Encoding::UTF_8).truncate(10)
+    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".dup.force_encoding(Encoding::UTF_8),
+      "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".dup.force_encoding(Encoding::UTF_8).truncate(10)
   end
 
   def test_truncate_should_not_be_html_safe
@@ -326,7 +326,7 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_remove!
-    original = "This is a very good day to die"
+    original = "This is a very good day to die".dup
     assert_equal "This is a good day to die", original.remove!(" very")
     assert_equal "This is a good day to die", original
     assert_equal "This is a good day", original.remove!(" to ", /die/)
@@ -659,7 +659,7 @@ end
 
 class OutputSafetyTest < ActiveSupport::TestCase
   def setup
-    @string = "hello"
+    @string = "hello".dup
     @object = Class.new(Object) do
       def to_s
         "other"
@@ -735,7 +735,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   end
 
   test "Concatting safe onto unsafe yields unsafe" do
-    @other_string = "other"
+    @other_string = "other".dup
 
     string = @string.html_safe
     @other_string.concat(string)
@@ -758,7 +758,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   end
 
   test "Concatting safe onto unsafe with << yields unsafe" do
-    @other_string = "other"
+    @other_string = "other".dup
     string = @string.html_safe
 
     @other_string << string
@@ -814,7 +814,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   test "Concatting an integer to safe always yields safe" do
     string = @string.html_safe
     string = string.concat(13)
-    assert_equal "hello".concat(13), string
+    assert_equal "hello".dup.concat(13), string
     assert string.html_safe?
   end
 
@@ -869,7 +869,8 @@ end
 
 class StringIndentTest < ActiveSupport::TestCase
   test "does not indent strings that only contain newlines (edge cases)" do
-    ["", "\n", "\n" * 7].each do |str|
+    ["", "\n", "\n" * 7].each do |string|
+      str = string.dup
       assert_nil str.indent!(8)
       assert_equal str, str.indent(8)
       assert_equal str, str.indent(1, "\t")
diff --git a/activesupport/test/logger_test.rb b/activesupport/test/logger_test.rb
index 6b698ede67..cd0ddb4b97 100644
--- a/activesupport/test/logger_test.rb
+++ b/activesupport/test/logger_test.rb
@@ -38,7 +38,7 @@ class LoggerTest < ActiveSupport::TestCase
     logger = Logger.new f
     logger.level = Logger::DEBUG
 
-    str = "\x80"
+    str = "\x80".dup
     str.force_encoding("ASCII-8BIT")
 
     logger.add Logger::DEBUG, str
@@ -56,7 +56,7 @@ class LoggerTest < ActiveSupport::TestCase
     logger = Logger.new f
     logger.level = Logger::DEBUG
 
-    str = "\x80"
+    str = "\x80".dup
     str.force_encoding("ASCII-8BIT")
 
     logger.add Logger::DEBUG, str
diff --git a/activesupport/test/multibyte_chars_test.rb b/activesupport/test/multibyte_chars_test.rb
index 5d1743db1d..6bef794fe2 100644
--- a/activesupport/test/multibyte_chars_test.rb
+++ b/activesupport/test/multibyte_chars_test.rb
@@ -52,7 +52,7 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_forwarded_method_with_non_string_result_should_be_returned_verbatim
-    str = ""
+    str = "".dup
     str.singleton_class.class_eval { def __method_for_multibyte_testing_with_integer_result; 1; end }
     @chars.wrapped_string.singleton_class.class_eval { def __method_for_multibyte_testing_with_integer_result; 1; end }
 
@@ -60,14 +60,14 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   end
 
   def test_should_concatenate
-    mb_a = "a".mb_chars
-    mb_b = "b".mb_chars
+    mb_a = "a".dup.mb_chars
+    mb_b = "b".dup.mb_chars
     assert_equal "ab", mb_a + "b"
     assert_equal "ab", "a" + mb_b
     assert_equal "ab", mb_a + mb_b
 
     assert_equal "ab", mb_a << "b"
-    assert_equal "ab", "a" << mb_b
+    assert_equal "ab", "a".dup << mb_b
     assert_equal "abb", mb_a << mb_b
   end
 
@@ -79,7 +79,7 @@ class MultibyteCharsTest < ActiveSupport::TestCase
 
   def test_concatenation_should_return_a_proxy_class_instance
     assert_equal ActiveSupport::Multibyte.proxy_class, ("a".mb_chars + "b").class
-    assert_equal ActiveSupport::Multibyte.proxy_class, ("a".mb_chars << "b").class
+    assert_equal ActiveSupport::Multibyte.proxy_class, ("a".dup.mb_chars << "b").class
   end
 
   def test_ascii_strings_are_treated_at_utf8_strings
@@ -89,8 +89,8 @@ class MultibyteCharsTest < ActiveSupport::TestCase
   def test_concatenate_should_return_proxy_instance
     assert(("a".mb_chars + "b").kind_of?(@proxy_class))
     assert(("a".mb_chars + "b".mb_chars).kind_of?(@proxy_class))
-    assert(("a".mb_chars << "b").kind_of?(@proxy_class))
-    assert(("a".mb_chars << "b".mb_chars).kind_of?(@proxy_class))
+    assert(("a".dup.mb_chars << "b").kind_of?(@proxy_class))
+    assert(("a".dup.mb_chars << "b".mb_chars).kind_of?(@proxy_class))
   end
 
   def test_should_return_string_as_json
@@ -116,12 +116,12 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   %w{capitalize downcase lstrip reverse rstrip swapcase upcase}.each do |method|
     class_eval(<<-EOTESTS, __FILE__, __LINE__ + 1)
       def test_#{method}_bang_should_return_self_when_modifying_wrapped_string
-        chars = ' él piDió Un bUen café '
+        chars = ' él piDió Un bUen café '.dup
         assert_equal chars.object_id, chars.send("#{method}!").object_id
       end
 
       def test_#{method}_bang_should_change_wrapped_string
-        original = ' él piDió Un bUen café '
+        original = ' él piDió Un bUen café '.dup
         proxy = chars(original.dup)
         proxy.send("#{method}!")
         assert_not_equal original, proxy.to_s
@@ -134,7 +134,7 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_tidy_bytes_bang_should_change_wrapped_string
-    original = " Un bUen café \x92"
+    original = " Un bUen café \x92".dup
     proxy = chars(original.dup)
     proxy.tidy_bytes!
     assert_not_equal original, proxy.to_s
@@ -151,7 +151,7 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_string_methods_are_chainable
-    assert chars("").insert(0, "").kind_of?(ActiveSupport::Multibyte.proxy_class)
+    assert chars("".dup).insert(0, "").kind_of?(ActiveSupport::Multibyte.proxy_class)
     assert chars("").rjust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
     assert chars("").ljust(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
     assert chars("").center(1).kind_of?(ActiveSupport::Multibyte.proxy_class)
@@ -196,7 +196,7 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_should_use_character_offsets_for_insert_offsets
-    assert_equal "", "".mb_chars.insert(0, "")
+    assert_equal "", "".dup.mb_chars.insert(0, "")
     assert_equal "こわにちわ", @chars.insert(1, "わ")
     assert_equal "こわわわにちわ", @chars.insert(2, "わわ")
     assert_equal "わこわわわにちわ", @chars.insert(0, "わ")
@@ -419,13 +419,13 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_slice_bang_removes_the_slice_from_the_receiver
-    chars = "úüù".mb_chars
+    chars = "úüù".dup.mb_chars
     chars.slice!(0, 2)
     assert_equal "ù", chars
   end
 
   def test_slice_bang_returns_nil_and_does_not_modify_receiver_if_out_of_bounds
-    string = "úüù"
+    string = "úüù".dup
     chars = string.mb_chars
     assert_nil chars.slice!(4, 5)
     assert_equal "úüù", chars
diff --git a/activesupport/test/multibyte_test_helpers.rb b/activesupport/test/multibyte_test_helpers.rb
index 8e7587fa4e..c3346c233a 100644
--- a/activesupport/test/multibyte_test_helpers.rb
+++ b/activesupport/test/multibyte_test_helpers.rb
@@ -24,7 +24,7 @@ module MultibyteTestHelpers
 
   UNICODE_STRING = "こにちわ".freeze
   ASCII_STRING = "ohayo".freeze
-  BYTE_STRING = "\270\236\010\210\245".force_encoding("ASCII-8BIT").freeze
+  BYTE_STRING = "\270\236\010\210\245".dup.force_encoding("ASCII-8BIT").freeze
 
   def chars(str)
     ActiveSupport::Multibyte::Chars.new(str)
diff --git a/guides/source/command_line.md b/guides/source/command_line.md
index 3360496c08..9fddbf76b6 100644
--- a/guides/source/command_line.md
+++ b/guides/source/command_line.md
@@ -262,12 +262,12 @@ $ bin/rails db:migrate
 ==  CreateHighScores: migrated (0.0019s) ======================================
 ```
 
-INFO: Let's talk about unit tests. Unit tests are code that tests and makes assertions 
-about code. In unit testing, we take a little part of code, say a method of a model, 
-and test its inputs and outputs. Unit tests are your friend. The sooner you make 
-peace with the fact that your quality of life will drastically increase when you unit 
-test your code, the better. Seriously. Please visit 
-[the testing guide](http://guides.rubyonrails.org/testing.html) for an in-depth 
+INFO: Let's talk about unit tests. Unit tests are code that tests and makes assertions
+about code. In unit testing, we take a little part of code, say a method of a model,
+and test its inputs and outputs. Unit tests are your friend. The sooner you make
+peace with the fact that your quality of life will drastically increase when you unit
+test your code, the better. Seriously. Please visit
+[the testing guide](http://guides.rubyonrails.org/testing.html) for an in-depth
 look at unit testing.
 
 Let's see the interface Rails created for us.
@@ -533,7 +533,8 @@ The `tmp:` namespaced tasks will help you clear and create the `Rails.root/tmp`
 
 * `rails tmp:cache:clear` clears `tmp/cache`.
 * `rails tmp:sockets:clear` clears `tmp/sockets`.
-* `rails tmp:clear` clears all cache and sockets files.
+* `rails tmp:screenshots:clear` clears `tmp/screenshots`.
+* `rails tmp:clear` clears all cache, sockets and screenshot files.
 * `rails tmp:create` creates tmp directories for cache, sockets and pids.
 
 ### Miscellaneous
diff --git a/railties/CHANGELOG.md b/railties/CHANGELOG.md
index b9a530258d..7d94336207 100644
--- a/railties/CHANGELOG.md
+++ b/railties/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Clear screenshot files in `tmp:clear` task.
+
+    *Yuji Yaginuma*
+
 *   Add `railtie.rb` to the plugin generator
 
     *Tsukuru Tanimichi*
diff --git a/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
index b78a12f926..1d02ec909e 100644
--- a/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/rails/scaffold/scaffold_generator.rb
@@ -17,13 +17,10 @@ module Rails
       def handle_skip
         @options = @options.merge(stylesheets: false) unless options[:assets]
         @options = @options.merge(stylesheet_engine: false) unless options[:stylesheets] && options[:scaffold_stylesheet]
-        @options = @options.merge(system_tests: false) if options[:api]
       end
 
       hook_for :scaffold_controller, required: true
 
-      hook_for :system_tests, as: :system
-
       hook_for :assets do |assets|
         invoke assets, [controller_name]
       end
diff --git a/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
index 72ba5ce650..9772317053 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/scaffold_generator.rb
@@ -12,12 +12,19 @@ module TestUnit # :nodoc:
       class_option :api, type: :boolean,
                          desc: "Generates API functional tests"
 
+      class_option :system_tests, type: :string,
+                         desc: "Skip system test files"
+
       argument :attributes, type: :array, default: [], banner: "field:type field:type"
 
       def create_test_files
         template_file = options.api? ? "api_functional_test.rb" : "functional_test.rb"
         template template_file,
                  File.join("test/controllers", controller_class_path, "#{controller_file_name}_controller_test.rb")
+
+        unless options.api? || options[:system_tests].nil?
+          template "system_test.rb", File.join("test/system", class_path, "#{file_name.pluralize}_test.rb")
+        end
       end
 
       def fixture_name
@@ -31,16 +38,20 @@ module TestUnit # :nodoc:
 
       private
 
+        def attributes_string
+          attributes_hash.map { |k, v| "#{k}: #{v}" }.join(", ")
+        end
+
         def attributes_hash
-          return if attributes_names.empty?
+          return {} if attributes_names.empty?
 
           attributes_names.map do |name|
             if %w(password password_confirmation).include?(name) && attributes.any?(&:password_digest?)
-              "#{name}: 'secret'"
+              ["#{name}", "'secret'"]
             else
-              "#{name}: @#{singular_table_name}.#{name}"
+              ["#{name}", "@#{singular_table_name}.#{name}"]
             end
-          end.sort.join(", ")
+          end.sort.to_h
         end
     end
   end
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb b/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb
index c469c188e6..f21861d8e6 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/api_functional_test.rb
@@ -17,7 +17,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should create <%= singular_table_name %>" do
     assert_difference('<%= class_name %>.count') do
-      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }, as: :json
+      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }, as: :json
     end
 
     assert_response 201
@@ -29,7 +29,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
   end
 
   test "should update <%= singular_table_name %>" do
-    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }, as: :json
+    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }, as: :json
     assert_response 200
   end
 
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb b/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb
index c33375b7b4..195d60be20 100644
--- a/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb
@@ -22,7 +22,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should create <%= singular_table_name %>" do
     assert_difference('<%= class_name %>.count') do
-      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }
+      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
     end
 
     assert_redirected_to <%= singular_table_name %>_url(<%= class_name %>.last)
@@ -39,7 +39,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
   end
 
   test "should update <%= singular_table_name %>" do
-    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_hash} }" %> }
+    patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
     assert_redirected_to <%= singular_table_name %>_url(<%= "@#{singular_table_name}" %>)
   end
 
diff --git a/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb b/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb
new file mode 100644
index 0000000000..f83f5a5c62
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/scaffold/templates/system_test.rb
@@ -0,0 +1,49 @@
+require "application_system_test_case"
+
+<% module_namespacing do -%>
+class <%= class_name.pluralize %>Test < ApplicationSystemTestCase
+  setup do
+    @<%= singular_table_name %> = <%= fixture_name %>(:one)
+  end
+
+  test "visiting the index" do
+    visit <%= plural_table_name %>_url
+    assert_selector "h1", text: "<%= class_name.pluralize.titleize %>"
+  end
+
+  test "creating a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    click_on "New <%= class_name.titleize %>"
+
+    <%- attributes_hash.each do |attr, value| -%>
+    fill_in "<%= attr.humanize.titleize %>", with: <%= value %>
+    <%- end -%>
+    click_on "Create <%= human_name %>"
+
+    assert_text "<%= human_name %> was successfully created"
+    click_on "Back"
+  end
+
+  test "updating a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    click_on "Edit", match: :first
+
+    <%- attributes_hash.each do |attr, value| -%>
+    fill_in "<%= attr.humanize.titleize %>", with: <%= value %>
+    <%- end -%>
+    click_on "Update <%= human_name %>"
+
+    assert_text "<%= human_name %> was successfully updated"
+    click_on "Back"
+  end
+
+  test "destroying a <%= human_name %>" do
+    visit <%= plural_table_name %>_url
+    page.accept_confirm do
+      click_on "Destroy", match: :first
+    end
+
+    assert_text "<%= human_name %> was successfully destroyed"
+  end
+end
+<% end -%>
diff --git a/railties/lib/rails/tasks/tmp.rake b/railties/lib/rails/tasks/tmp.rake
index 95769a38be..2e082a309f 100644
--- a/railties/lib/rails/tasks/tmp.rake
+++ b/railties/lib/rails/tasks/tmp.rake
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 namespace :tmp do
-  desc "Clear cache and socket files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear)"
-  task clear: ["tmp:cache:clear", "tmp:sockets:clear"]
+  desc "Clear cache, socket and screenshot files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear, tmp:screenshots:clear)"
+  task clear: ["tmp:cache:clear", "tmp:sockets:clear", "tmp:screenshots:clear"]
 
   tmp_dirs = [ "tmp/cache",
                "tmp/sockets",
@@ -33,4 +33,11 @@ namespace :tmp do
       rm Dir["tmp/pids/[^.]*"], verbose: false
     end
   end
+
+  namespace :screenshots do
+    # desc "Clears all files in tmp/screenshots"
+    task :clear do
+      rm Dir["tmp/screenshots/[^.]*"], verbose: false
+    end
+  end
 end
diff --git a/railties/railties.gemspec b/railties/railties.gemspec
index 2195e99059..b6bad76a89 100644
--- a/railties/railties.gemspec
+++ b/railties/railties.gemspec
@@ -24,6 +24,11 @@ Gem::Specification.new do |s|
 
   s.rdoc_options << "--exclude" << "."
 
+  s.metadata = {
+    "source_code_uri" => "https://github.com/rails/rails/tree/v#{version}/railties",
+    "changelog_uri"   => "https://github.com/rails/rails/blob/v#{version}/railties/CHANGELOG.md"
+  }
+
   s.add_dependency "activesupport", version
   s.add_dependency "actionpack",    version
 
diff --git a/railties/test/application/rake/tmp_test.rb b/railties/test/application/rake/tmp_test.rb
new file mode 100644
index 0000000000..d8f684dbe9
--- /dev/null
+++ b/railties/test/application/rake/tmp_test.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+require "isolation/abstract_unit"
+
+module ApplicationTests
+  module RakeTests
+    class TmpTest < ActiveSupport::TestCase
+      include ActiveSupport::Testing::Isolation
+
+      def setup
+        build_app
+      end
+
+      def teardown
+        teardown_app
+      end
+
+      test "tmp:clear clear cache, socket and screenshot files" do
+        Dir.chdir(app_path) do
+          FileUtils.mkdir_p("tmp/cache")
+          FileUtils.touch("tmp/cache/cache_file")
+
+          FileUtils.mkdir_p("tmp/sockets")
+          FileUtils.touch("tmp/sockets/socket_file")
+
+          FileUtils.mkdir_p("tmp/screenshots")
+          FileUtils.touch("tmp/screenshots/fail.png")
+
+          `rails tmp:clear`
+
+          assert_not File.exist?("tmp/cache/cache_file")
+          assert_not File.exist?("tmp/sockets/socket_file")
+          assert_not File.exist?("tmp/screenshots/fail.png")
+        end
+      end
+    end
+  end
+end
diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 2f4ea8ed28..554c57d670 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -438,7 +438,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generator_if_skip_system_test_is_given
-    run_generator [destination_root, "--skip_system_test"]
+    run_generator [destination_root, "--skip-system-test"]
     assert_file "Gemfile" do |content|
       assert_no_match(/capybara/, content)
       assert_no_match(/selenium-webdriver/, content)
@@ -446,7 +446,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_does_not_generate_system_test_files_if_skip_system_test_is_given
-    run_generator [destination_root, "--skip_system_test"]
+    run_generator [destination_root, "--skip-system-test"]
 
     Dir.chdir(destination_root) do
       quietly { `./bin/rails g scaffold User` }
diff --git a/railties/test/generators/scaffold_generator_test.rb b/railties/test/generators/scaffold_generator_test.rb
index 0141701b52..4956ca21b0 100644
--- a/railties/test/generators/scaffold_generator_test.rb
+++ b/railties/test/generators/scaffold_generator_test.rb
@@ -66,6 +66,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     # System tests
     assert_file "test/system/product_lines_test.rb" do |test|
       assert_match(/class ProductLinesTest < ApplicationSystemTestCase/, test)
+      assert_match(/visit product_lines_url/, test)
+      assert_match(/fill_in "Title", with: @product_line\.title/, test)
+      assert_match(/assert_text "Product line was successfully updated"/, test)
     end
 
     # Views
@@ -147,6 +150,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_no_match(/assert_redirected_to/, test)
     end
 
+    # System tests
+    assert_no_file "test/system/product_lines_test.rb"
+
     # Views
     assert_no_file "app/views/layouts/product_lines.html.erb"
 
@@ -174,6 +180,16 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_system_tests_without_attributes
+    run_generator ["product_line"]
+
+    assert_file "test/system/product_lines_test.rb" do |content|
+      assert_match(/class ProductLinesTest < ApplicationSystemTestCase/, content)
+      assert_match(/test "visiting the index"/, content)
+      assert_no_match(/fill_in/, content)
+    end
+  end
+
   def test_scaffold_on_revoke
     run_generator
     run_generator ["product_line"], behavior: :revoke
@@ -193,6 +209,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_no_file "app/controllers/product_lines_controller.rb"
     assert_no_file "test/controllers/product_lines_controller_test.rb"
 
+    # System tests
+    assert_no_file "test/system/product_lines_test.rb"
+
     # Views
     assert_no_file "app/views/product_lines"
     assert_no_file "app/views/layouts/product_lines.html.erb"
@@ -258,6 +277,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_file "test/controllers/admin/roles_controller_test.rb",
                 /class Admin::RolesControllerTest < ActionDispatch::IntegrationTest/
 
+    assert_file "test/system/admin/roles_test.rb",
+                /class Admin::RolesTest < ApplicationSystemTestCase/
+
     # Views
     %w(index edit new show _form).each do |view|
       assert_file "app/views/admin/roles/#{view}.html.erb"
@@ -293,6 +315,9 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     assert_no_file "app/controllers/admin/roles_controller.rb"
     assert_no_file "test/controllers/admin/roles_controller_test.rb"
 
+    # System tests
+    assert_no_file "test/system/admin/roles_test.rb"
+
     # Views
     assert_no_file "app/views/admin/roles"
     assert_no_file "app/views/layouts/admin/roles.html.erb"
@@ -479,6 +504,11 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_match(/password_confirmation: 'secret'/, content)
     end
 
+    assert_file "test/system/users_test.rb" do |content|
+      assert_match(/fill_in "Password", with: 'secret'/, content)
+      assert_match(/fill_in "Password Confirmation", with: 'secret'/, content)
+    end
+
     assert_file "test/fixtures/users.yml" do |content|
       assert_match(/password_digest: <%= BCrypt::Password.create\('secret'\) %>/, content)
     end
@@ -574,6 +604,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert File.exist?("app/controllers/bukkits/users_controller.rb")
       assert File.exist?("test/controllers/bukkits/users_controller_test.rb")
 
+      assert File.exist?("test/system/bukkits/users_test.rb")
+
       assert File.exist?("app/views/bukkits/users/index.html.erb")
       assert File.exist?("app/views/bukkits/users/edit.html.erb")
       assert File.exist?("app/views/bukkits/users/show.html.erb")
@@ -602,6 +634,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
       assert_not File.exist?("app/controllers/bukkits/users_controller.rb")
       assert_not File.exist?("test/controllers/bukkits/users_controller_test.rb")
 
+      assert_not File.exist?("test/system/bukkits/users_test.rb")
+
       assert_not File.exist?("app/views/bukkits/users/index.html.erb")
       assert_not File.exist?("app/views/bukkits/users/edit.html.erb")
       assert_not File.exist?("app/views/bukkits/users/show.html.erb")