8 files changed, 55 insertions, 9 deletions
diff --git a/actionpack/test/abstract_unit.rb b/actionpack/test/abstract_unit.rb
index bd118b46be..caa56018f8 100644
--- a/actionpack/test/abstract_unit.rb
+++ b/actionpack/test/abstract_unit.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 $:.unshift File.expand_path("lib", __dir__)
 $:.unshift File.expand_path("fixtures/helpers", __dir__)
 $:.unshift File.expand_path("fixtures/alternate_helpers", __dir__)
@@ -175,7 +177,7 @@ end
 class Rack::TestCase < ActionDispatch::IntegrationTest
   def self.testing(klass = nil)
     if klass
-      @testing = "/#{klass.name.underscore}".sub!(/_controller$/, "")
+      @testing = "/#{klass.name.underscore}".sub(/_controller$/, "")
     else
       @testing
     end
diff --git a/actionpack/test/controller/request_forgery_protection_test.rb b/actionpack/test/controller/request_forgery_protection_test.rb
index 521d93f02e..4d441ab1a9 100644
--- a/actionpack/test/controller/request_forgery_protection_test.rb
+++ b/actionpack/test/controller/request_forgery_protection_test.rb
@@ -163,6 +163,13 @@ class PerFormTokensController < ActionController::Base
   end
 end
 
+class SkipProtectionController < ActionController::Base
+  include RequestForgeryProtectionActions
+  protect_from_forgery with: :exception
+  skip_forgery_protection if: :skip_requested
+  attr_accessor :skip_requested
+end
+
 # common test methods
 module RequestForgeryProtectionTests
   def setup
@@ -964,3 +971,26 @@ class PerFormTokensControllerTest < ActionController::TestCase
       assert_equal expected, actual
     end
 end
+
+class SkipProtectionControllerTest < ActionController::TestCase
+  def test_should_not_allow_post_without_token_when_not_skipping
+    @controller.skip_requested = false
+    assert_blocked { post :index }
+  end
+
+  def test_should_allow_post_without_token_when_skipping
+    @controller.skip_requested = true
+    assert_not_blocked { post :index }
+  end
+
+  def assert_blocked
+    assert_raises(ActionController::InvalidAuthenticityToken) do
+      yield
+    end
+  end
+
+  def assert_not_blocked
+    assert_nothing_raised { yield }
+    assert_response :success
+  end
+end
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index 56b39510bb..fefb84e095 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "controller/fake_controllers"
 require "active_support/core_ext/object/with_options"
@@ -656,7 +658,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     assert_equal "/page/foo", url_for(rs, controller: "content", action: "show_page", id: "foo")
     assert_equal({ controller: "content", action: "show_page", id: "foo" }, rs.recognize_path("/page/foo"))
 
-    token = "\321\202\320\265\320\272\321\201\321\202" # 'text' in Russian
+    token = "\321\202\320\265\320\272\321\201\321\202".dup # 'text' in Russian
     token.force_encoding(Encoding::BINARY)
     escaped_token = CGI::escape(token)
 
diff --git a/actionpack/test/dispatch/debug_exceptions_test.rb b/actionpack/test/dispatch/debug_exceptions_test.rb
index ea477e8908..60acba0616 100644
--- a/actionpack/test/dispatch/debug_exceptions_test.rb
+++ b/actionpack/test/dispatch/debug_exceptions_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 class DebugExceptionsTest < ActionDispatch::IntegrationTest
@@ -344,7 +346,7 @@ class DebugExceptionsTest < ActionDispatch::IntegrationTest
     })
     assert_response 500
 
-    assert_includes(body, CGI.escapeHTML(PP.pp(params, "", 200)))
+    assert_includes(body, CGI.escapeHTML(PP.pp(params, "".dup, 200)))
   end
 
   test "sets the HTTP charset parameter" do
diff --git a/actionpack/test/dispatch/prefix_generation_test.rb b/actionpack/test/dispatch/prefix_generation_test.rb
index 0e093d2188..85ea04356a 100644
--- a/actionpack/test/dispatch/prefix_generation_test.rb
+++ b/actionpack/test/dispatch/prefix_generation_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "rack/test"
 require "rails/engine"
@@ -11,7 +13,7 @@ module TestGenerationPrefix
     end
 
     def self.model_name
-      klass = "Post"
+      klass = "Post".dup
       def klass.name; self end
 
       ActiveModel::Name.new(klass)
diff --git a/actionpack/test/dispatch/static_test.rb b/actionpack/test/dispatch/static_test.rb
index 3082d1072b..0bdff68692 100644
--- a/actionpack/test/dispatch/static_test.rb
+++ b/actionpack/test/dispatch/static_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "zlib"
 
@@ -29,7 +31,7 @@ module StaticTests
   end
 
   def test_handles_urls_with_ascii_8bit
-    assert_equal "Hello, World!", get("/doorkeeper%E3E4".force_encoding("ASCII-8BIT")).body
+    assert_equal "Hello, World!", get("/doorkeeper%E3E4".dup.force_encoding("ASCII-8BIT")).body
   end
 
   def test_handles_urls_with_ascii_8bit_on_win_31j
@@ -37,7 +39,7 @@ module StaticTests
       Encoding.default_internal = "Windows-31J"
       Encoding.default_external = "Windows-31J"
     end
-    assert_equal "Hello, World!", get("/doorkeeper%E3E4".force_encoding("ASCII-8BIT")).body
+    assert_equal "Hello, World!", get("/doorkeeper%E3E4".dup.force_encoding("ASCII-8BIT")).body
   end
 
   def test_handles_urls_with_null_byte
diff --git a/actionpack/test/dispatch/system_testing/driver_test.rb b/actionpack/test/dispatch/system_testing/driver_test.rb
index 4a1b971da5..34d27671bb 100644
--- a/actionpack/test/dispatch/system_testing/driver_test.rb
+++ b/actionpack/test/dispatch/system_testing/driver_test.rb
@@ -29,7 +29,7 @@ class DriverTest < ActiveSupport::TestCase
     assert_equal ({ skip_image_loading: true }), driver.instance_variable_get(:@options)
   end
 
-  test "rack_test? returns false if driver is poltergeist" do
-    assert_not ActionDispatch::SystemTesting::Driver.new(:poltergeist).send(:rack_test?)
+  test "registerable? returns false if driver is rack_test" do
+    assert_not ActionDispatch::SystemTesting::Driver.new(:rack_test).send(:registerable?)
   end
 end
diff --git a/actionpack/test/journey/router/utils_test.rb b/actionpack/test/journey/router/utils_test.rb
index 74277a4325..646563f7ab 100644
--- a/actionpack/test/journey/router/utils_test.rb
+++ b/actionpack/test/journey/router/utils_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 
 module ActionDispatch
@@ -21,7 +23,7 @@ module ActionDispatch
         end
 
         def test_uri_unescape_with_utf8_string
-          assert_equal "Šašinková", Utils.unescape_uri("%C5%A0a%C5%A1inkov%C3%A1".force_encoding(Encoding::US_ASCII))
+          assert_equal "Šašinková", Utils.unescape_uri("%C5%A0a%C5%A1inkov%C3%A1".dup.force_encoding(Encoding::US_ASCII))
         end
 
         def test_normalize_path_not_greedy
@@ -36,6 +38,10 @@ module ActionDispatch
           path = "/foo%AAbar%AAbaz".b
           assert_equal Encoding::ASCII_8BIT, Utils.normalize_path(path).encoding
         end
+
+        def test_normalize_path_with_nil
+          assert_equal '/', Utils.normalize_path(nil)
+        end
       end
     end
   end