Pass symbol as an argument instead of a block

120 files changed, 244 insertions, 276 deletions

diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index 23139bcbe8..a88e884ee8 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -859,7 +859,7 @@ module ActionMailer
       when user_content_type.present?
         user_content_type
       when m.has_attachments?
-        if m.attachments.detect { |a| a.inline? }
+        if m.attachments.detect(&:inline?)
           ["multipart", "related", params]
         else
           ["multipart", "mixed", params]
@@ -914,7 +914,7 @@ module ActionMailer
       if templates.empty?
         raise ActionView::MissingTemplate.new(paths, name, paths, false, 'mailer')
       else
-        templates.uniq { |t| t.formats }.each(&block)
+        templates.uniq(&:formats).each(&block)
       end
     end
 
diff --git a/actionpack/lib/abstract_controller/base.rb b/actionpack/lib/abstract_controller/base.rb
index 4026dab2ce..51c661f735 100644
--- a/actionpack/lib/abstract_controller/base.rb
+++ b/actionpack/lib/abstract_controller/base.rb
@@ -82,7 +82,7 @@ module AbstractController
             # Except for public instance methods of Base and its ancestors
             internal_methods +
             # Be sure to include shadowed public instance methods of this class
-            public_instance_methods(false)).uniq.map { |x| x.to_s } -
+            public_instance_methods(false)).uniq.map(&:to_s) -
             # And always exclude explicitly hidden actions
             hidden_actions.to_a
 
diff --git a/actionpack/lib/action_controller/metal/testing.rb b/actionpack/lib/action_controller/metal/testing.rb
index dd8da4b5dc..d01927b7cb 100644
--- a/actionpack/lib/action_controller/metal/testing.rb
+++ b/actionpack/lib/action_controller/metal/testing.rb
@@ -24,7 +24,7 @@ module ActionController
 
     module ClassMethods
       def before_filters
-        _process_action_callbacks.find_all{|x| x.kind == :before}.map{|x| x.name}
+        _process_action_callbacks.find_all{|x| x.kind == :before}.map(&:name)
       end
     end
   end
diff --git a/actionpack/lib/action_dispatch/http/mime_type.rb b/actionpack/lib/action_dispatch/http/mime_type.rb
index b9d5009683..047a17937a 100644
--- a/actionpack/lib/action_dispatch/http/mime_type.rb
+++ b/actionpack/lib/action_dispatch/http/mime_type.rb
@@ -6,7 +6,7 @@ require 'active_support/core_ext/string/starts_ends_with'
 module Mime
   class Mimes < Array
     def symbols
-      @symbols ||= map { |m| m.to_sym }
+      @symbols ||= map(&:to_sym)
     end
 
     %w(<< concat shift unshift push pop []= clear compact! collect!
diff --git a/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb b/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
index 66e414213a..e65f7238ab 100644
--- a/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
+++ b/actionpack/lib/action_dispatch/journey/nfa/transition_table.rb
@@ -107,7 +107,7 @@ module ActionDispatch
         end
 
         def alphabet
-          inverted.values.flat_map(&:keys).compact.uniq.sort_by { |x| x.to_s }
+          inverted.values.flat_map(&:keys).compact.uniq.sort_by(&:to_s)
         end
 
         # Returns a set of NFA states reachable from some NFA state +s+ in set
diff --git a/actionpack/lib/action_dispatch/journey/path/pattern.rb b/actionpack/lib/action_dispatch/journey/path/pattern.rb
index 3af940a02f..dca83e806c 100644
--- a/actionpack/lib/action_dispatch/journey/path/pattern.rb
+++ b/actionpack/lib/action_dispatch/journey/path/pattern.rb
@@ -42,7 +42,7 @@ module ActionDispatch
         end
 
         def names
-          @names ||= spec.grep(Nodes::Symbol).map { |n| n.name }
+          @names ||= spec.grep(Nodes::Symbol).map(&:name)
         end
 
         def required_names
@@ -52,7 +52,7 @@ module ActionDispatch
         def optional_names
           @optional_names ||= spec.grep(Nodes::Group).flat_map { |group|
             group.grep(Nodes::Symbol)
-          }.map { |n| n.name }.uniq
+          }.map(&:name).uniq
         end
 
         class RegexpOffsets < Journey::Visitors::Visitor # :nodoc:
diff --git a/actionpack/lib/action_dispatch/journey/route.rb b/actionpack/lib/action_dispatch/journey/route.rb
index 9f0a3af902..3b609a184d 100644
--- a/actionpack/lib/action_dispatch/journey/route.rb
+++ b/actionpack/lib/action_dispatch/journey/route.rb
@@ -60,7 +60,7 @@ module ActionDispatch
       end
 
       def parts
-        @parts ||= segments.map { |n| n.to_sym }
+        @parts ||= segments.map(&:to_sym)
       end
       alias :segment_keys :parts
 
@@ -69,11 +69,11 @@ module ActionDispatch
       end
 
       def optional_parts
-        path.optional_names.map { |n| n.to_sym }
+        path.optional_names.map(&:to_sym)
       end
 
       def required_parts
-        @required_parts ||= path.required_names.map { |n| n.to_sym }
+        @required_parts ||= path.required_names.map(&:to_sym)
       end
 
       def required_default?(key)
diff --git a/actionpack/lib/action_dispatch/journey/router.rb b/actionpack/lib/action_dispatch/journey/router.rb
index 9131b65380..2b036796ab 100644
--- a/actionpack/lib/action_dispatch/journey/router.rb
+++ b/actionpack/lib/action_dispatch/journey/router.rb
@@ -68,8 +68,8 @@ module ActionDispatch
 
       def visualizer
         tt     = GTG::Builder.new(ast).transition_table
-        groups = partitioned_routes.first.map(&:ast).group_by { |a| a.to_s }
-        asts   = groups.values.map { |v| v.first }
+        groups = partitioned_routes.first.map(&:ast).group_by(&:to_s)
+        asts   = groups.values.map(&:first)
         tt.visualizer(asts)
       end
 
diff --git a/actionpack/lib/action_dispatch/routing/inspector.rb b/actionpack/lib/action_dispatch/routing/inspector.rb
index cfe2237512..df5ebb6751 100644
--- a/actionpack/lib/action_dispatch/routing/inspector.rb
+++ b/actionpack/lib/action_dispatch/routing/inspector.rb
@@ -114,9 +114,7 @@ module ActionDispatch
       def collect_routes(routes)
         routes.collect do |route|
           RouteWrapper.new(route)
-        end.reject do |route|
-          route.internal?
-        end.collect do |route|
+        end.reject(&:internal?).collect do |route|
           collect_engine_routes(route)
 
           { name:   route.name,
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 6e3ae36a7f..c2cacbd288 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -543,7 +543,7 @@ module ActionDispatch
         path = conditions.delete :path_info
         ast  = conditions.delete :parsed_path_info
         path = build_path(path, ast, requirements, anchor)
-        conditions = build_conditions(conditions, path.names.map { |x| x.to_sym })
+        conditions = build_conditions(conditions, path.names.map(&:to_sym))
 
         route = @set.add_route(app, path, conditions, defaults, name)
         named_routes[name] = route if name
@@ -605,7 +605,7 @@ module ActionDispatch
           if name == :controller
             value
           elsif value.is_a?(Array)
-            value.map { |v| v.to_param }.join('/')
+            value.map(&:to_param).join('/')
           elsif param = value.to_param
             param
           end
diff --git a/actionpack/lib/action_dispatch/testing/test_request.rb b/actionpack/lib/action_dispatch/testing/test_request.rb
index de3dc5f924..4b9a088265 100644
--- a/actionpack/lib/action_dispatch/testing/test_request.rb
+++ b/actionpack/lib/action_dispatch/testing/test_request.rb
@@ -60,7 +60,7 @@ module ActionDispatch
 
     def accept=(mime_types)
       @env.delete('action_dispatch.request.accepts')
-      @env['HTTP_ACCEPT'] = Array(mime_types).collect { |mime_type| mime_type.to_s }.join(",")
+      @env['HTTP_ACCEPT'] = Array(mime_types).collect(&:to_s).join(",")
     end
 
     alias :rack_cookies :cookies
diff --git a/actionpack/test/abstract_unit.rb b/actionpack/test/abstract_unit.rb
index 63c9ab04c9..57c076eac6 100644
--- a/actionpack/test/abstract_unit.rb
+++ b/actionpack/test/abstract_unit.rb
@@ -53,7 +53,7 @@ I18n.enforce_available_locales = false
 # Register danish language for testing
 I18n.backend.store_translations 'da', {}
 I18n.backend.store_translations 'pt-BR', {}
-ORIGINAL_LOCALES = I18n.available_locales.map {|locale| locale.to_s }.sort
+ORIGINAL_LOCALES = I18n.available_locales.map(&:to_s).sort
 
 FIXTURE_LOAD_PATH = File.join(File.dirname(__FILE__), 'fixtures')
 FIXTURES = Pathname.new(FIXTURE_LOAD_PATH)
diff --git a/actionpack/test/controller/filters_test.rb b/actionpack/test/controller/filters_test.rb
index b2b01b3fa9..38533dbf23 100644
--- a/actionpack/test/controller/filters_test.rb
+++ b/actionpack/test/controller/filters_test.rb
@@ -10,7 +10,7 @@ class ActionController::Base
 
     def before_actions
       filters = _process_action_callbacks.select { |c| c.kind == :before }
-      filters.map! { |c| c.raw_filter }
+      filters.map!(&:raw_filter)
     end
   end
 
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index f46b32e019..9caa5cbe57 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -884,13 +884,13 @@ class RouteSetTest < ActiveSupport::TestCase
     set.draw { get ':controller/(:action(/:id))' }
     path, extras = set.generate_extras(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
     assert_equal "/foo/bar/15", path
-    assert_equal %w(that this), extras.map { |e| e.to_s }.sort
+    assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_extra_keys
     set.draw { get ':controller/:action/:id' }
     extras = set.extra_keys(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
-    assert_equal %w(that this), extras.map { |e| e.to_s }.sort
+    assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_generate_extras_not_first
@@ -900,7 +900,7 @@ class RouteSetTest < ActiveSupport::TestCase
     end
     path, extras = set.generate_extras(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
     assert_equal "/foo/bar/15", path
-    assert_equal %w(that this), extras.map { |e| e.to_s }.sort
+    assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_generate_not_first
@@ -918,7 +918,7 @@ class RouteSetTest < ActiveSupport::TestCase
       get ':controller/:action/:id'
     end
     extras = set.extra_keys(:controller => "foo", :action => "bar", :id => 15, :this => "hello", :that => "world")
-    assert_equal %w(that this), extras.map { |e| e.to_s }.sort
+    assert_equal %w(that this), extras.map(&:to_s).sort
   end
 
   def test_draw
diff --git a/actionpack/test/dispatch/mime_type_test.rb b/actionpack/test/dispatch/mime_type_test.rb
index ad6335f132..3017a9c2d6 100644
--- a/actionpack/test/dispatch/mime_type_test.rb
+++ b/actionpack/test/dispatch/mime_type_test.rb
@@ -83,7 +83,7 @@ class MimeTypeTest < ActiveSupport::TestCase
   test "parse broken acceptlines" do
     accept = "text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/*,,*/*;q=0.5"
     expect = [Mime::HTML, Mime::XML, "image/*", Mime::TEXT, Mime::ALL]
-    assert_equal expect, Mime::Type.parse(accept).collect { |c| c.to_s }
+    assert_equal expect, Mime::Type.parse(accept).collect(&:to_s)
   end
 
   # Accept header send with user HTTP_USER_AGENT: Mozilla/4.0
@@ -91,7 +91,7 @@ class MimeTypeTest < ActiveSupport::TestCase
   test "parse other broken acceptlines" do
     accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword,  , pronto/1.00.00, sslvpn/1.00.00.00, */*"
     expect = ['image/gif', 'image/x-xbitmap', 'image/jpeg','image/pjpeg', 'application/x-shockwave-flash', 'application/vnd.ms-excel', 'application/vnd.ms-powerpoint', 'application/msword', 'pronto/1.00.00', 'sslvpn/1.00.00.00', Mime::ALL]
-    assert_equal expect, Mime::Type.parse(accept).collect { |c| c.to_s }
+    assert_equal expect, Mime::Type.parse(accept).collect(&:to_s)
   end
 
   test "custom type" do
diff --git a/actionview/lib/action_view/helpers/date_helper.rb b/actionview/lib/action_view/helpers/date_helper.rb
index bd7b36c352..4b4f0ae577 100644
--- a/actionview/lib/action_view/helpers/date_helper.rb
+++ b/actionview/lib/action_view/helpers/date_helper.rb
@@ -898,7 +898,7 @@ module ActionView
 
         def translated_date_order
           date_order = I18n.translate(:'date.order', :locale => @options[:locale], :default => [])
-          date_order = date_order.map { |element| element.to_sym }
+          date_order = date_order.map(&:to_sym)
 
           forbidden_elements = date_order - [:year, :month, :day]
           if forbidden_elements.any?
diff --git a/actionview/lib/action_view/helpers/form_options_helper.rb b/actionview/lib/action_view/helpers/form_options_helper.rb
index 83b07a00d4..bbfbf482a4 100644
--- a/actionview/lib/action_view/helpers/form_options_helper.rb
+++ b/actionview/lib/action_view/helpers/form_options_helper.rb
@@ -351,12 +351,12 @@ module ActionView
         return container if String === container
 
         selected, disabled = extract_selected_and_disabled(selected).map do |r|
-          Array(r).map { |item| item.to_s }
+          Array(r).map(&:to_s)
         end
 
         container.map do |element|
           html_attributes = option_html_attributes(element)
-          text, value = option_text_and_value(element).map { |item| item.to_s }
+          text, value = option_text_and_value(element).map(&:to_s)
 
           html_attributes[:selected] ||= option_value_selected?(value, selected)
           html_attributes[:disabled] ||= disabled && option_value_selected?(value, disabled)
diff --git a/actionview/lib/action_view/helpers/tag_helper.rb b/actionview/lib/action_view/helpers/tag_helper.rb
index b2038576a2..a87c223a71 100644
--- a/actionview/lib/action_view/helpers/tag_helper.rb
+++ b/actionview/lib/action_view/helpers/tag_helper.rb
@@ -18,7 +18,7 @@ module ActionView
                            itemscope allowfullscreen default inert sortable
                            truespeed typemustmatch).to_set
 
-      BOOLEAN_ATTRIBUTES.merge(BOOLEAN_ATTRIBUTES.map {|attribute| attribute.to_sym })
+      BOOLEAN_ATTRIBUTES.merge(BOOLEAN_ATTRIBUTES.map(&:to_sym))
 
       TAG_PREFIXES = ['aria', 'data', :aria, :data].to_set
 
diff --git a/actionview/lib/action_view/layouts.rb b/actionview/lib/action_view/layouts.rb
index 9ee05bd816..0b5c0b9991 100644
--- a/actionview/lib/action_view/layouts.rb
+++ b/actionview/lib/action_view/layouts.rb
@@ -262,7 +262,7 @@ module ActionView
       def layout(layout, conditions = {})
         include LayoutConditions unless conditions.empty?
 
-        conditions.each {|k, v| conditions[k] = Array(v).map {|a| a.to_s} }
+        conditions.each {|k, v| conditions[k] = Array(v).map(&:to_s) }
         self._layout_conditions = conditions
 
         self._layout = layout
diff --git a/actionview/lib/action_view/template/error.rb b/actionview/lib/action_view/template/error.rb
index 743ef6de0a..390bce98a2 100644
--- a/actionview/lib/action_view/template/error.rb
+++ b/actionview/lib/action_view/template/error.rb
@@ -75,7 +75,7 @@ module ActionView
       def sub_template_message
         if @sub_templates
           "Trace of template inclusion: " +
-          @sub_templates.collect { |template| template.inspect }.join(", ")
+          @sub_templates.collect(&:inspect).join(", ")
         else
           ""
         end
diff --git a/actionview/lib/action_view/template/handlers.rb b/actionview/lib/action_view/template/handlers.rb
index ff2feb5149..9e61ea4225 100644
--- a/actionview/lib/action_view/template/handlers.rb
+++ b/actionview/lib/action_view/template/handlers.rb
@@ -42,7 +42,7 @@ module ActionView #:nodoc:
       end
 
       def template_handler_extensions
-        @@template_handlers.keys.map {|key| key.to_s }.sort
+        @@template_handlers.keys.map(&:to_s).sort
       end
 
       def registered_template_handler(extension)
diff --git a/actionview/lib/action_view/template/resolver.rb b/actionview/lib/action_view/template/resolver.rb
index b65507f4a2..29d2e9ca90 100644
--- a/actionview/lib/action_view/template/resolver.rb
+++ b/actionview/lib/action_view/template/resolver.rb
@@ -139,7 +139,7 @@ module ActionView
     # resolver is fresher before returning it.
     def cached(key, path_info, details, locals) #:nodoc:
       name, prefix, partial = path_info
-      locals = locals.map { |x| x.to_s }.sort!
+      locals = locals.map(&:to_s).sort!
 
       if key
         @cache.cache(key, name, prefix, partial, locals) do
diff --git a/actionview/lib/action_view/template/types.rb b/actionview/lib/action_view/template/types.rb
index b84e0281ae..be45fcf742 100644
--- a/actionview/lib/action_view/template/types.rb
+++ b/actionview/lib/action_view/template/types.rb
@@ -9,7 +9,7 @@ module ActionView
         self.types = Set.new
 
         def self.register(*t)
-          types.merge(t.map { |type| type.to_s })
+          types.merge(t.map(&:to_s))
         end
 
         register :html, :text, :js, :css,  :xml, :json
diff --git a/actionview/test/abstract_unit.rb b/actionview/test/abstract_unit.rb
index 7096d588b6..4aa56f60f7 100644
--- a/actionview/test/abstract_unit.rb
+++ b/actionview/test/abstract_unit.rb
@@ -46,7 +46,7 @@ I18n.enforce_available_locales = false
 # Register danish language for testing
 I18n.backend.store_translations 'da', {}
 I18n.backend.store_translations 'pt-BR', {}
-ORIGINAL_LOCALES = I18n.available_locales.map {|locale| locale.to_s }.sort
+ORIGINAL_LOCALES = I18n.available_locales.map(&:to_s).sort
 
 FIXTURE_LOAD_PATH = File.join(File.dirname(__FILE__), 'fixtures')
 FIXTURES = Pathname.new(FIXTURE_LOAD_PATH)
diff --git a/actionview/test/actionpack/controller/view_paths_test.rb b/actionview/test/actionpack/controller/view_paths_test.rb
index c6e7a523b9..7fba9ff8ff 100644
--- a/actionview/test/actionpack/controller/view_paths_test.rb
+++ b/actionview/test/actionpack/controller/view_paths_test.rb
@@ -39,7 +39,7 @@ class ViewLoadPathsTest < ActionController::TestCase
 
   def assert_paths(*paths)
     controller = paths.first.is_a?(Class) ? paths.shift : @controller
-    assert_equal expand(paths), controller.view_paths.map { |p| p.to_s }
+    assert_equal expand(paths), controller.view_paths.map(&:to_s)
   end
 
   def test_template_load_path_was_set_correctly
diff --git a/actionview/test/template/erb_util_test.rb b/actionview/test/template/erb_util_test.rb
index 3bb84cbc50..3e72be31de 100644
--- a/actionview/test/template/erb_util_test.rb
+++ b/actionview/test/template/erb_util_test.rb
@@ -84,7 +84,7 @@ class ErbUtilTest < ActiveSupport::TestCase
   end
 
   def test_rest_in_ascii
-    (0..127).to_a.map {|int| int.chr }.each do |chr|
+    (0..127).to_a.map(&:chr).each do |chr|
       next if %('"&<>).include?(chr)
       assert_equal chr, html_escape(chr)
     end
diff --git a/actionview/test/template/render_test.rb b/actionview/test/template/render_test.rb
index 85817119ba..4e502bede9 100644
--- a/actionview/test/template/render_test.rb
+++ b/actionview/test/template/render_test.rb
@@ -16,7 +16,7 @@ module RenderTestCases
     I18n.backend.store_translations 'pt-BR', {}
 
     # Ensure original are still the same since we are reindexing view paths
-    assert_equal ORIGINAL_LOCALES, I18n.available_locales.map {|l| l.to_s }.sort
+    assert_equal ORIGINAL_LOCALES, I18n.available_locales.map(&:to_s).sort
   end
 
   def test_render_without_options
diff --git a/activejob/test/support/delayed_job/delayed/backend/test.rb b/activejob/test/support/delayed_job/delayed/backend/test.rb
index b50ed36fc2..f80ec3a5a6 100644
--- a/activejob/test/support/delayed_job/delayed/backend/test.rb
+++ b/activejob/test/support/delayed_job/delayed/backend/test.rb
@@ -43,9 +43,7 @@ module Delayed
         end
 
         def self.create(attrs = {})
-          new(attrs).tap do |o|
-            o.save
-          end
+          new(attrs).tap(&:save)
         end
 
         def self.create!(*args); create(*args); end
diff --git a/activejob/test/support/integration/adapters/sidekiq.rb b/activejob/test/support/integration/adapters/sidekiq.rb
index 3cc9a34993..bdc61a1462 100644
--- a/activejob/test/support/integration/adapters/sidekiq.rb
+++ b/activejob/test/support/integration/adapters/sidekiq.rb
@@ -48,7 +48,7 @@ module SidekiqJobsManager
 
   def can_run?
     begin
-      Sidekiq.redis { |conn| conn.connect }
+      Sidekiq.redis(&:connect)
     rescue
       return false
     end
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index 3834d327ea..12a22f9c40 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -59,7 +59,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
 
   def test_validates_numericality_of_with_integer_only_and_proc_as_value
     Topic.send(:define_method, :allow_only_integers?, lambda { false })
-    Topic.validates_numericality_of :approved, only_integer: Proc.new {|topic| topic.allow_only_integers? }
+    Topic.validates_numericality_of :approved, only_integer: Proc.new(&:allow_only_integers?)
 
     invalid!(NIL + BLANK + JUNK)
     valid!(FLOATS + INTEGERS + BIGDECIMAL + INFINITY)
@@ -130,7 +130,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
 
   def test_validates_numericality_with_proc
     Topic.send(:define_method, :min_approved, lambda { 5 })
-    Topic.validates_numericality_of :approved, greater_than_or_equal_to: Proc.new {|topic| topic.min_approved }
+    Topic.validates_numericality_of :approved, greater_than_or_equal_to: Proc.new(&:min_approved)
 
     invalid!([3, 4])
     valid!([5, 6])
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index de71bb6f42..98e0266d7e 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -282,7 +282,7 @@ class ValidationsTest < ActiveModel::TestCase
       ActiveModel::Validations::FormatValidator,
       ActiveModel::Validations::LengthValidator,
       ActiveModel::Validations::PresenceValidator
-    ], validators.map { |v| v.class }.sort_by { |c| c.to_s }
+    ], validators.map(&:class).sort_by(&:to_s)
   end
 
   def test_list_of_validators_will_be_empty_when_empty
diff --git a/activerecord/examples/performance.rb b/activerecord/examples/performance.rb
index d3546ce948..a5a1f284a0 100644
--- a/activerecord/examples/performance.rb
+++ b/activerecord/examples/performance.rb
@@ -39,8 +39,8 @@ class Exhibit < ActiveRecord::Base
     where("notes IS NOT NULL")
   end
 
-  def self.look(exhibits) exhibits.each { |e| e.look } end
-  def self.feel(exhibits) exhibits.each { |e| e.feel } end
+  def self.look(exhibits) exhibits.each(&:look) end
+  def self.feel(exhibits) exhibits.each(&:feel) end
 end
 
 def progress_bar(int); print "." if (int%100).zero? ; end
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index d2bcdc55bf..eb21712f96 100644
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -57,7 +57,7 @@ module ActiveRecord
       through_reflection      = reflection.through_reflection
       source_reflection_names = reflection.source_reflection_names
       source_associations     = reflection.through_reflection.klass._reflections.keys
-      super("Could not find the source association(s) #{source_reflection_names.collect{ |a| a.inspect }.to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)}?")
+      super("Could not find the source association(s) #{source_reflection_names.collect(&:inspect).to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)}?")
     end
   end
 
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 2b7d39893d..7b6aefe345 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -62,9 +62,9 @@ module ActiveRecord
       # Implements the ids writer method, e.g. foo.item_ids= for Foo.has_many :items
       def ids_writer(ids)
         pk_type = reflection.primary_key_type
-        ids = Array(ids).reject { |id| id.blank? }
+        ids = Array(ids).reject(&:blank?)
         ids.map! { |i| pk_type.type_cast_from_user(i) }
-        replace(klass.find(ids).index_by { |r| r.id }.values_at(*ids))
+        replace(klass.find(ids).index_by(&:id).values_at(*ids))
       end
 
       def reset
@@ -289,7 +289,7 @@ module ActiveRecord
         elsif !loaded? && !association_scope.group_values.empty?
           load_target.size
         elsif !loaded? && !association_scope.distinct_value && target.is_a?(Array)
-          unsaved_records = target.select { |r| r.new_record? }
+          unsaved_records = target.select(&:new_record?)
           unsaved_records.size + count_records
         else
           count_records
@@ -506,7 +506,7 @@ module ActiveRecord
         def delete_or_destroy(records, method)
           records = records.flatten
           records.each { |record| raise_on_type_mismatch!(record) }
-          existing_records = records.reject { |r| r.new_record? }
+          existing_records = records.reject(&:new_record?)
 
           if existing_records.empty?
             remove_records(existing_records, records, method)
@@ -609,7 +609,7 @@ module ActiveRecord
         # specified, then #find scans the entire collection.
         def find_by_scan(*args)
           expects_array = args.first.kind_of?(Array)
-          ids           = args.flatten.compact.map{ |arg| arg.to_s }.uniq
+          ids           = args.flatten.compact.map(&:to_s).uniq
 
           if ids.size == 1
             id = ids.first
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 6329fdfe95..5cfedcc009 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -161,9 +161,7 @@ module ActiveRecord
             if scope.klass.primary_key
               count = scope.destroy_all.length
             else
-              scope.each do |record|
-                record._run_destroy_callbacks
-              end
+              scope.each(&:_run_destroy_callbacks)
 
               arel = scope.arel
 
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 285d0ec9af..cf63430a97 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -20,7 +20,7 @@ module ActiveRecord
         end
 
         def columns
-          @tables.flat_map { |t| t.column_aliases }
+          @tables.flat_map(&:column_aliases)
         end
 
         # An array of [column_name, alias] pairs for the table
diff --git a/activerecord/lib/active_record/associations/preloader/has_many_through.rb b/activerecord/lib/active_record/associations/preloader/has_many_through.rb
index 7b37b5942d..2029871f39 100644
--- a/activerecord/lib/active_record/associations/preloader/has_many_through.rb
+++ b/activerecord/lib/active_record/associations/preloader/has_many_through.rb
@@ -8,7 +8,7 @@ module ActiveRecord
           records_by_owner = super
 
           if reflection_scope.distinct_value
-            records_by_owner.each_value { |records| records.uniq! }
+            records_by_owner.each_value(&:uniq!)
           end
 
           records_by_owner
diff --git a/activerecord/lib/active_record/attribute_assignment.rb b/activerecord/lib/active_record/attribute_assignment.rb
index 2887db3bf7..bf64830417 100644
--- a/activerecord/lib/active_record/attribute_assignment.rb
+++ b/activerecord/lib/active_record/attribute_assignment.rb
@@ -87,7 +87,7 @@ module ActiveRecord
         end
       end
       unless errors.empty?
-        error_descriptions = errors.map { |ex| ex.message }.join(",")
+        error_descriptions = errors.map(&:message).join(",")
         raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes [#{error_descriptions}]"
       end
     end
diff --git a/activerecord/lib/active_record/autosave_association.rb b/activerecord/lib/active_record/autosave_association.rb
index a0d70435fa..c39b045a5e 100644
--- a/activerecord/lib/active_record/autosave_association.rb
+++ b/activerecord/lib/active_record/autosave_association.rb
@@ -263,9 +263,9 @@ module ActiveRecord
         if new_record
           association && association.target
         elsif autosave
-          association.target.find_all { |record| record.changed_for_autosave? }
+          association.target.find_all(&:changed_for_autosave?)
         else
-          association.target.find_all { |record| record.new_record? }
+          association.target.find_all(&:new_record?)
         end
       end
 
@@ -275,7 +275,7 @@ module ActiveRecord
         self.class._reflections.values.any? do |reflection|
           if reflection.options[:autosave]
             association = association_instance_get(reflection.name)
-            association && Array.wrap(association.target).any? { |a| a.changed_for_autosave? }
+            association && Array.wrap(association.target).any?(&:changed_for_autosave?)
           end
         end
       end
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 46812b75bb..3a9db4a109 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -320,9 +320,7 @@ module ActiveRecord
             checkin conn
             conn.disconnect! if conn.requires_reloading?
           end
-          @connections.delete_if do |conn|
-            conn.requires_reloading?
-          end
+          @connections.delete_if(&:requires_reloading?)
           @available.clear
           @connections.each do |conn|
             @available.add conn
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 99fa9b7d29..aa7c406050 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -781,7 +781,7 @@ module ActiveRecord
         version = version.to_i
         sm_table = quote_table_name(ActiveRecord::Migrator.schema_migrations_table_name)
 
-        migrated = select_values("SELECT version FROM #{sm_table}").map { |v| v.to_i }
+        migrated = select_values("SELECT version FROM #{sm_table}").map(&:to_i)
         paths = migrations_paths.map {|p| "#{p}/[0-9]*_*.rb" }
         versions = Dir[*paths].map do |filename|
           filename.split('/').last.split('_').first.to_i
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 c824a7b11b..bf16804aa0 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -398,7 +398,7 @@ module ActiveRecord
         sql << "LIKE #{quote(like)}" if like
 
         execute_and_free(sql, 'SCHEMA') do |result|
-          result.collect { |field| field.first }
+          result.collect(&:first)
         end
       end
 
@@ -786,7 +786,7 @@ module ActiveRecord
       private
 
       def version
-        @version ||= full_version.scan(/^(\d+)\.(\d+)\.(\d+)/).flatten.map { |v| v.to_i }
+        @version ||= full_version.scan(/^(\d+)\.(\d+)\.(\d+)/).flatten.map(&:to_i)
       end
 
       def mariadb?
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index 53ad71b445..23d8389abb 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -423,9 +423,7 @@ module ActiveRecord
 
           cols = nil
           if metadata = stmt.result_metadata
-            cols = cache[:cols] ||= metadata.fetch_fields.map { |field|
-              field.name
-            }
+            cols = cache[:cols] ||= metadata.fetch_fields.map(&:name)
             metadata.free
           end
 
diff --git a/activerecord/lib/active_record/connection_adapters/schema_cache.rb b/activerecord/lib/active_record/connection_adapters/schema_cache.rb
index a10ce330c7..37ff4e4613 100644
--- a/activerecord/lib/active_record/connection_adapters/schema_cache.rb
+++ b/activerecord/lib/active_record/connection_adapters/schema_cache.rb
@@ -61,9 +61,7 @@ module ActiveRecord
       end
 
       def size
-        [@columns, @columns_hash, @primary_keys, @tables].map { |x|
-          x.size
-        }.inject :+
+        [@columns, @columns_hash, @primary_keys, @tables].map(&:size).inject :+
       end
 
       # Clear out internal caches for table with +table_name+.
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index 0b8b6a2bf8..c3865a8fdd 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -88,11 +88,11 @@ module ActiveRecord
         include Comparable
 
         def initialize(version_string)
-          @version = version_string.split('.').map { |v| v.to_i }
+          @version = version_string.split('.').map(&:to_i)
         end
 
         def <=>(version_string)
-          @version <=> version_string.split('.').map { |v| v.to_i }
+          @version <=> version_string.split('.').map(&:to_i)
         end
       end
 
@@ -556,7 +556,7 @@ module ActiveRecord
           end
           copy_table_indexes(from, to, options[:rename] || {})
           copy_table_contents(from, to,
-            @definition.columns.map {|column| column.name},
+            @definition.columns.map(&:name),
             options[:rename] || {})
         end
 
@@ -569,7 +569,7 @@ module ActiveRecord
               name = name[1..-1]
             end
 
-            to_column_names = columns(to).map { |c| c.name }
+            to_column_names = columns(to).map(&:name)
             columns = index.columns.map {|c| rename[c] || c }.select do |column|
               to_column_names.include?(column)
             end
@@ -586,7 +586,7 @@ module ActiveRecord
         def copy_table_contents(from, to, columns, rename = {}) #:nodoc:
           column_mappings = Hash[columns.map {|name| [name, name]}]
           rename.each { |a| column_mappings[a.last] = a.first }
-          from_columns = columns(from).collect {|col| col.name}
+          from_columns = columns(from).collect(&:name)
           columns = columns.find_all{|col| from_columns.include?(column_mappings[col])}
           quoted_columns = columns.map { |col| quote_column_name(col) } * ','
 
diff --git a/activerecord/lib/active_record/fixtures.rb b/activerecord/lib/active_record/fixtures.rb
index 7c53ee0a9a..4732462b05 100644
--- a/activerecord/lib/active_record/fixtures.rb
+++ b/activerecord/lib/active_record/fixtures.rb
@@ -745,7 +745,7 @@ module ActiveRecord
       end
 
       def column_names
-        @column_names ||= @connection.columns(@table_name).collect { |c| c.name }
+        @column_names ||= @connection.columns(@table_name).collect(&:name)
       end
 
       def read_fixture_files(path, model_class)
@@ -868,7 +868,7 @@ module ActiveRecord
           fixture_set_names = Dir["#{fixture_path}/{**,*}/*.{yml}"]
           fixture_set_names.map! { |f| f[(fixture_path.to_s.size + 1)..-5] }
         else
-          fixture_set_names = fixture_set_names.flatten.map { |n| n.to_s }
+          fixture_set_names = fixture_set_names.flatten.map(&:to_s)
         end
 
         self.fixture_table_names |= fixture_set_names
@@ -908,7 +908,7 @@ module ActiveRecord
 
       def uses_transaction(*methods)
         @uses_transaction = [] unless defined?(@uses_transaction)
-        @uses_transaction.concat methods.map { |m| m.to_s }
+        @uses_transaction.concat methods.map(&:to_s)
       end
 
       def uses_transaction?(method)
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb
index f58145ab05..b91e9ac137 100644
--- a/activerecord/lib/active_record/inheritance.rb
+++ b/activerecord/lib/active_record/inheritance.rb
@@ -192,7 +192,7 @@ module ActiveRecord
 
       def type_condition(table = arel_table)
         sti_column = table[inheritance_column]
-        sti_names  = ([self] + descendants).map { |model| model.sti_name }
+        sti_names  = ([self] + descendants).map(&:sti_name)
 
         sti_column.in(sti_names)
       end
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index 92f2951f2d..3cac465440 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -647,7 +647,7 @@ module ActiveRecord
     end
 
     def method_missing(method, *arguments, &block)
-      arg_list = arguments.map{ |a| a.inspect } * ', '
+      arg_list = arguments.map(&:inspect) * ', '
 
       say_with_time "#{method}(#{arg_list})" do
         unless @connection.respond_to? :revert
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index adad7774b9..92ad9c9101 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -257,7 +257,7 @@ module ActiveRecord
 
       # Returns an array of column names as strings.
       def column_names
-        @column_names ||= columns.map { |column| column.name }
+        @column_names ||= columns.map(&:name)
       end
 
       # Returns an array of column objects where the primary id, all columns ending in "_id" or "_count",
diff --git a/activerecord/lib/active_record/railties/databases.rake b/activerecord/lib/active_record/railties/databases.rake
index 21b1c3f721..6c09456c4d 100644
--- a/activerecord/lib/active_record/railties/databases.rake
+++ b/activerecord/lib/active_record/railties/databases.rake
@@ -366,7 +366,7 @@ namespace :railties do
   namespace :install do
     # desc "Copies missing migrations from Railties (e.g. engines). You can specify Railties to use with FROM=railtie1,railtie2"
     task :migrations => :'db:load_config' do
-      to_load = ENV['FROM'].blank? ? :all : ENV['FROM'].split(",").map {|n| n.strip }
+      to_load = ENV['FROM'].blank? ? :all : ENV['FROM'].split(",").map(&:strip)
       railties = {}
       Rails.application.migration_railties.each do |railtie|
         next unless to_load == :all || to_load.include?(railtie.railtie_name)
diff --git a/activerecord/lib/active_record/readonly_attributes.rb b/activerecord/lib/active_record/readonly_attributes.rb
index 85bbac43e4..ce78f1756d 100644
--- a/activerecord/lib/active_record/readonly_attributes.rb
+++ b/activerecord/lib/active_record/readonly_attributes.rb
@@ -11,7 +11,7 @@ module ActiveRecord
       # Attributes listed as readonly will be used to create a new record but update operations will
       # ignore these fields.
       def attr_readonly(*attributes)
-        self._attr_readonly = Set.new(attributes.map { |a| a.to_s }) + (self._attr_readonly || [])
+        self._attr_readonly = Set.new(attributes.map(&:to_s)) + (self._attr_readonly || [])
       end
 
       # Returns an array of all the attributes that have been specified as readonly.
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 4219632596..96520d1d49 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -791,7 +791,7 @@ module ActiveRecord
       def source_reflection_name # :nodoc:
         return @source_reflection_name if @source_reflection_name
 
-        names = [name.to_s.singularize, name].collect { |n| n.to_sym }.uniq
+        names = [name.to_s.singularize, name].collect(&:to_sym).uniq
         names = names.find_all { |n|
           through_reflection.klass._reflect_on_association(n)
         }
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 561ed222d1..7e1994086f 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -400,7 +400,7 @@ module ActiveRecord
       if conditions
         where(conditions).destroy_all
       else
-        to_a.each {|object| object.destroy }.tap { reset }
+        to_a.each(&:destroy).tap { reset }
       end
     end
 
@@ -644,7 +644,7 @@ module ActiveRecord
         preloader.preload @records, associations
       end
 
-      @records.each { |record| record.readonly! } if readonly_value
+      @records.each(&:readonly!) if readonly_value
 
       @loaded = true
       @records
@@ -666,7 +666,7 @@ module ActiveRecord
       joined_tables += [table.name, table.table_alias]
 
       # always convert table names to downcase as in Oracle quoted table names are in uppercase
-      joined_tables = joined_tables.flatten.compact.map { |t| t.downcase }.uniq
+      joined_tables = joined_tables.flatten.compact.map(&:downcase).uniq
 
       (references_values - joined_tables).any?
     end
@@ -675,7 +675,7 @@ module ActiveRecord
       return [] if string.blank?
       # always convert table names to downcase as in Oracle quoted table names are in uppercase
       # ignore raw_sql_ that is used by Oracle adapter as alias for limit/offset subqueries
-      string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map{ |s| s.downcase }.uniq - ['raw_sql_']
+      string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map(&:downcase).uniq - ['raw_sql_']
     end
   end
 end
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index eacae73ebb..5061940d82 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -415,7 +415,7 @@ module ActiveRecord
     end
 
     def using_limitable_reflections?(reflections)
-      reflections.none? { |r| r.collection? }
+      reflections.none?(&:collection?)
     end
 
     protected
diff --git a/activerecord/lib/active_record/serialization.rb b/activerecord/lib/active_record/serialization.rb
index bd9079b596..48c12dcf9f 100644
--- a/activerecord/lib/active_record/serialization.rb
+++ b/activerecord/lib/active_record/serialization.rb
@@ -11,7 +11,7 @@ module ActiveRecord #:nodoc:
     def serializable_hash(options = nil)
       options = options.try(:clone) || {}
 
-      options[:except] = Array(options[:except]).map { |n| n.to_s }
+      options[:except] = Array(options[:except]).map(&:to_s)
       options[:except] |= Array(self.class.inheritance_column)
 
       super(options)
diff --git a/activerecord/lib/active_record/statement_cache.rb b/activerecord/lib/active_record/statement_cache.rb
index c68990bf99..192a19f05d 100644
--- a/activerecord/lib/active_record/statement_cache.rb
+++ b/activerecord/lib/active_record/statement_cache.rb
@@ -79,7 +79,7 @@ module ActiveRecord
       end
 
       def bind(values)
-        bvs = @bind_values.map { |pair| pair.dup }
+        bvs = @bind_values.map(&:dup)
         @indexes.each_with_index { |offset,i| bvs[offset][1] = values[i] }
         bvs
       end
diff --git a/activerecord/lib/active_record/validations/presence.rb b/activerecord/lib/active_record/validations/presence.rb
index c7aa814ba8..61b30749d9 100644
--- a/activerecord/lib/active_record/validations/presence.rb
+++ b/activerecord/lib/active_record/validations/presence.rb
@@ -8,7 +8,7 @@ module ActiveRecord
           associated_records = Array.wrap(record.send(attribute))
 
           # Superclass validates presence. Ensure present records aren't about to be destroyed.
-          if associated_records.present? && associated_records.all? { |r| r.marked_for_destruction? }
+          if associated_records.present? && associated_records.all?(&:marked_for_destruction?)
             record.errors.add(attribute, :blank, options)
           end
         end
diff --git a/activerecord/test/cases/adapters/mysql/connection_test.rb b/activerecord/test/cases/adapters/mysql/connection_test.rb
index 52eebe1886..ce01b16362 100644
--- a/activerecord/test/cases/adapters/mysql/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql/connection_test.rb
@@ -47,9 +47,7 @@ class MysqlConnectionTest < ActiveRecord::TestCase
     assert !@connection.active?
 
     # Repair all fixture connections so other tests won't break.
-    @fixture_connections.each do |c|
-      c.verify!
-    end
+    @fixture_connections.each(&:verify!)
   end
 
   def test_successful_reconnection_after_timeout_with_manual_reconnect
diff --git a/activerecord/test/cases/adapters/mysql/reserved_word_test.rb b/activerecord/test/cases/adapters/mysql/reserved_word_test.rb
index 61ae0abfd1..403f7cbc74 100644
--- a/activerecord/test/cases/adapters/mysql/reserved_word_test.rb
+++ b/activerecord/test/cases/adapters/mysql/reserved_word_test.rb
@@ -101,7 +101,7 @@ class MysqlReservedWordTest < ActiveRecord::TestCase
     gs = nil
     assert_nothing_raised { gs = Select.find(2).groups }
     assert_equal gs.length, 2
-    assert(gs.collect{|x| x.id}.sort == [2, 3])
+    assert(gs.collect(&:id).sort == [2, 3])
   end
 
   # has_and_belongs_to_many with reserved-word table name
@@ -110,7 +110,7 @@ class MysqlReservedWordTest < ActiveRecord::TestCase
     s = nil
     assert_nothing_raised { s = Distinct.find(1).selects }
     assert_equal s.length, 2
-    assert(s.collect{|x|x.id}.sort == [1, 2])
+    assert(s.collect(&:id).sort == [1, 2])
   end
 
   # activerecord model introspection with reserved-word table and column names
diff --git a/activerecord/test/cases/adapters/mysql/schema_test.rb b/activerecord/test/cases/adapters/mysql/schema_test.rb
index 87c5277e64..ab547747df 100644
--- a/activerecord/test/cases/adapters/mysql/schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql/schema_test.rb
@@ -81,7 +81,7 @@ module ActiveRecord
 
         table = 'key_tests'
 
-        indexes = @connection.indexes(table).sort_by {|i| i.name}
+        indexes = @connection.indexes(table).sort_by(&:name)
         assert_equal 3,indexes.size
 
         index_a = indexes.select{|i| i.name == index_a_name}[0]
diff --git a/activerecord/test/cases/adapters/mysql2/connection_test.rb b/activerecord/test/cases/adapters/mysql2/connection_test.rb
index 62c5abbf41..d261e2db55 100644
--- a/activerecord/test/cases/adapters/mysql2/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/connection_test.rb
@@ -44,9 +44,7 @@ class MysqlConnectionTest < ActiveRecord::TestCase
     assert !@connection.active?
 
     # Repair all fixture connections so other tests won't break.
-    @fixture_connections.each do |c|
-      c.verify!
-    end
+    @fixture_connections.each(&:verify!)
   end
 
   def test_successful_reconnection_after_timeout_with_manual_reconnect
diff --git a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb b/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
index 799d927ee4..7f97b454bb 100644
--- a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
@@ -100,7 +100,7 @@ class MysqlReservedWordTest < ActiveRecord::TestCase
     gs = nil
     assert_nothing_raised { gs = Select.find(2).groups }
     assert_equal gs.length, 2
-    assert(gs.collect{|x| x.id}.sort == [2, 3])
+    assert(gs.collect(&:id).sort == [2, 3])
   end
 
   # has_and_belongs_to_many with reserved-word table name
@@ -109,7 +109,7 @@ class MysqlReservedWordTest < ActiveRecord::TestCase
     s = nil
     assert_nothing_raised { s = Distinct.find(1).selects }
     assert_equal s.length, 2
-    assert(s.collect{|x|x.id}.sort == [1, 2])
+    assert(s.collect(&:id).sort == [1, 2])
   end
 
   # activerecord model introspection with reserved-word table and column names
diff --git a/activerecord/test/cases/adapters/mysql2/schema_test.rb b/activerecord/test/cases/adapters/mysql2/schema_test.rb
index 1b7e60565d..47707b7d4f 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_test.rb
@@ -51,7 +51,7 @@ module ActiveRecord
 
         table = 'key_tests'
 
-        indexes = @connection.indexes(table).sort_by {|i| i.name}
+        indexes = @connection.indexes(table).sort_by(&:name)
         assert_equal 3,indexes.size
 
         index_a = indexes.select{|i| i.name == index_a_name}[0]
diff --git a/activerecord/test/cases/adapters/postgresql/connection_test.rb b/activerecord/test/cases/adapters/postgresql/connection_test.rb
index 7d179944d4..ab7fd3c6d5 100644
--- a/activerecord/test/cases/adapters/postgresql/connection_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/connection_test.rb
@@ -177,9 +177,7 @@ module ActiveRecord
         "successfully querying with the same connection pid."
 
       # Repair all fixture connections so other tests won't break.
-      @fixture_connections.each do |c|
-        c.verify!
-      end
+      @fixture_connections.each(&:verify!)
     end
 
     def test_set_session_variable_true
diff --git a/activerecord/test/cases/adapters/postgresql/schema_test.rb b/activerecord/test/cases/adapters/postgresql/schema_test.rb
index 350cb3e065..92c9a13ee3 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_test.rb
@@ -412,7 +412,7 @@ class SchemaTest < ActiveRecord::TestCase
 
     def do_dump_index_tests_for_schema(this_schema_name, first_index_column_name, second_index_column_name, third_index_column_name, fourth_index_column_name)
       with_schema_search_path(this_schema_name) do
-        indexes = @connection.indexes(TABLE_NAME).sort_by {|i| i.name}
+        indexes = @connection.indexes(TABLE_NAME).sort_by(&:name)
         assert_equal 4,indexes.size
 
         do_dump_index_assertions_for_one_index(indexes[0], INDEX_A_NAME, first_index_column_name)
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index d83c65cf0e..9d09ff49c7 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -327,11 +327,11 @@ module ActiveRecord
 
       def test_columns
         with_example_table do
-          columns = @conn.columns('ex').sort_by { |x| x.name }
+          columns = @conn.columns('ex').sort_by(&:name)
           assert_equal 2, columns.length
-          assert_equal %w{ id number }.sort, columns.map { |x| x.name }
-          assert_equal [nil, nil], columns.map { |x| x.default }
-          assert_equal [true, true], columns.map { |x| x.null }
+          assert_equal %w{ id number }.sort, columns.map(&:name)
+          assert_equal [nil, nil], columns.map(&:default)
+          assert_equal [true, true], columns.map(&:null)
         end
       end
 
diff --git a/activerecord/test/cases/associations/eager_load_nested_include_test.rb b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
index 0ff87d53ea..f571198079 100644
--- a/activerecord/test/cases/associations/eager_load_nested_include_test.rb
+++ b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
@@ -70,9 +70,7 @@ class EagerLoadPolyAssocsTest < ActiveRecord::TestCase
 
   teardown do
     [Circle, Square, Triangle, PaintColor, PaintTexture,
-     ShapeExpression, NonPolyOne, NonPolyTwo].each do |c|
-      c.delete_all
-    end
+     ShapeExpression, NonPolyOne, NonPolyTwo].each(&:delete_all)
   end
 
   def generate_test_object_graphs
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index f968a34886..4321a198ca 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -338,31 +338,31 @@ class EagerAssociationTest < ActiveRecord::TestCase
   def test_eager_association_loading_with_belongs_to_and_limit
     comments = Comment.all.merge!(:includes => :post, :limit => 5, :order => 'comments.id').to_a
     assert_equal 5, comments.length
-    assert_equal [1,2,3,5,6], comments.collect { |c| c.id }
+    assert_equal [1,2,3,5,6], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_conditions
     comments = Comment.all.merge!(:includes => :post, :where => 'post_id = 4', :limit => 3, :order => 'comments.id').to_a
     assert_equal 3, comments.length
-    assert_equal [5,6,7], comments.collect { |c| c.id }
+    assert_equal [5,6,7], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset
     comments = Comment.all.merge!(:includes => :post, :limit => 3, :offset => 2, :order => 'comments.id').to_a
     assert_equal 3, comments.length
-    assert_equal [3,5,6], comments.collect { |c| c.id }
+    assert_equal [3,5,6], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_conditions
     comments = Comment.all.merge!(:includes => :post, :where => 'post_id = 4', :limit => 3, :offset => 1, :order => 'comments.id').to_a
     assert_equal 3, comments.length
-    assert_equal [6,7,8], comments.collect { |c| c.id }
+    assert_equal [6,7,8], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_conditions_array
     comments = Comment.all.merge!(:includes => :post, :where => ['post_id = ?',4], :limit => 3, :offset => 1, :order => 'comments.id').to_a
     assert_equal 3, comments.length
-    assert_equal [6,7,8], comments.collect { |c| c.id }
+    assert_equal [6,7,8], comments.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_conditions_string_with_unquoted_table_name
@@ -377,7 +377,7 @@ class EagerAssociationTest < ActiveRecord::TestCase
       comments = Comment.all.merge!(:includes => :post, :where => {:posts => {:id => 4}}, :limit => 3, :order => 'comments.id').to_a
     end
     assert_equal 3, comments.length
-    assert_equal [5,6,7], comments.collect { |c| c.id }
+    assert_equal [5,6,7], comments.collect(&:id)
     assert_no_queries do
       comments.first.post
     end
@@ -406,13 +406,13 @@ class EagerAssociationTest < ActiveRecord::TestCase
   def test_eager_association_loading_with_belongs_to_and_limit_and_multiple_associations
     posts = Post.all.merge!(:includes => [:author, :very_special_comment], :limit => 1, :order => 'posts.id').to_a
     assert_equal 1, posts.length
-    assert_equal [1], posts.collect { |p| p.id }
+    assert_equal [1], posts.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_and_limit_and_offset_and_multiple_associations
     posts = Post.all.merge!(:includes => [:author, :very_special_comment], :limit => 1, :offset => 1, :order => 'posts.id').to_a
     assert_equal 1, posts.length
-    assert_equal [2], posts.collect { |p| p.id }
+    assert_equal [2], posts.collect(&:id)
   end
 
   def test_eager_association_loading_with_belongs_to_inferred_foreign_key_from_association_name
@@ -545,13 +545,13 @@ class EagerAssociationTest < ActiveRecord::TestCase
   def test_eager_with_has_many_and_limit_and_conditions
     posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :where => "posts.body = 'hello'", :order => "posts.id").to_a
     assert_equal 2, posts.size
-    assert_equal [4,5], posts.collect { |p| p.id }
+    assert_equal [4,5], posts.collect(&:id)
   end
 
   def test_eager_with_has_many_and_limit_and_conditions_array
     posts = Post.all.merge!(:includes => [ :author, :comments ], :limit => 2, :where => [ "posts.body = ?", 'hello' ], :order => "posts.id").to_a
     assert_equal 2, posts.size
-    assert_equal [4,5], posts.collect { |p| p.id }
+    assert_equal [4,5], posts.collect(&:id)
   end
 
   def test_eager_with_has_many_and_limit_and_conditions_array_on_the_eagers
diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index 092e85949c..aea9207bfe 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -555,7 +555,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
 
   def test_dynamic_find_all_should_respect_readonly_access
     projects(:active_record).readonly_developers.each { |d| assert_raise(ActiveRecord::ReadOnlyRecord) { d.save!  } if d.valid?}
-    projects(:active_record).readonly_developers.each { |d| d.readonly? }
+    projects(:active_record).readonly_developers.each(&:readonly?)
   end
 
   def test_new_with_values_in_collection
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 9510d57de6..c075872617 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -1219,7 +1219,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert !clients.empty?, "37signals has clients after load"
     destroyed = companies(:first_firm).clients_of_firm.destroy_all
     assert_equal clients.sort_by(&:id), destroyed.sort_by(&:id)
-    assert destroyed.all? { |client| client.frozen? }, "destroyed clients should be frozen"
+    assert destroyed.all?(&:frozen?), "destroyed clients should be frozen"
     assert companies(:first_firm).clients_of_firm.empty?, "37signals has no clients after destroy all"
     assert companies(:first_firm).clients_of_firm(true).empty?, "37signals has no clients after destroy all and refresh"
   end
diff --git a/activerecord/test/cases/associations/has_many_through_associations_test.rb b/activerecord/test/cases/associations/has_many_through_associations_test.rb
index d523ea4f07..589a232bdb 100644
--- a/activerecord/test/cases/associations/has_many_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_through_associations_test.rb
@@ -41,7 +41,7 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
   def test_preload_sti_rhs_class
     developers = Developer.includes(:firms).all.to_a
     assert_no_queries do
-      developers.each { |d| d.firms }
+      developers.each(&:firms)
     end
   end
 
diff --git a/activerecord/test/cases/associations/inner_join_association_test.rb b/activerecord/test/cases/associations/inner_join_association_test.rb
index 07cf65a760..9938302885 100644
--- a/activerecord/test/cases/associations/inner_join_association_test.rb
+++ b/activerecord/test/cases/associations/inner_join_association_test.rb
@@ -54,7 +54,7 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
   def test_find_with_implicit_inner_joins_without_select_does_not_imply_readonly
     authors = Author.joins(:posts)
     assert_not authors.empty?, "expected authors to be non-empty"
-    assert authors.none? {|a| a.readonly? }, "expected no authors to be readonly"
+    assert authors.none?(&:readonly?), "expected no authors to be readonly"
   end
 
   def test_find_with_implicit_inner_joins_honors_readonly_with_select
diff --git a/activerecord/test/cases/associations/join_model_test.rb b/activerecord/test/cases/associations/join_model_test.rb
index cace7ba142..140ccdac72 100644
--- a/activerecord/test/cases/associations/join_model_test.rb
+++ b/activerecord/test/cases/associations/join_model_test.rb
@@ -393,18 +393,18 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_polymorphic_has_one
-    assert_equal Tagging.find(1,2).sort_by { |t| t.id }, authors(:david).taggings_2
+    assert_equal Tagging.find(1,2).sort_by(&:id), authors(:david).taggings_2
   end
 
   def test_has_many_through_polymorphic_has_many
-    assert_equal taggings(:welcome_general, :thinking_general), authors(:david).taggings.distinct.sort_by { |t| t.id }
+    assert_equal taggings(:welcome_general, :thinking_general), authors(:david).taggings.distinct.sort_by(&:id)
   end
 
   def test_include_has_many_through_polymorphic_has_many
     author            = Author.includes(:taggings).find authors(:david).id
     expected_taggings = taggings(:welcome_general, :thinking_general)
     assert_no_queries do
-      assert_equal expected_taggings, author.taggings.distinct.sort_by { |t| t.id }
+      assert_equal expected_taggings, author.taggings.distinct.sort_by(&:id)
     end
   end
 
diff --git a/activerecord/test/cases/associations_test.rb b/activerecord/test/cases/associations_test.rb
index 04ef50e58a..c6769edcbf 100644
--- a/activerecord/test/cases/associations_test.rb
+++ b/activerecord/test/cases/associations_test.rb
@@ -48,7 +48,7 @@ class AssociationsTest < ActiveRecord::TestCase
     assert_kind_of Firm, firm
 
     firm.clear_association_cache
-    assert_equal Firm.find(1).clients.collect{ |x| x.name }.sort, firm.clients.collect{ |x| x.name }.sort
+    assert_equal Firm.find(1).clients.collect(&:name).sort, firm.clients.collect(&:name).sort
   end
 
   def test_clear_association_cache_new_record
diff --git a/activerecord/test/cases/autosave_association_test.rb b/activerecord/test/cases/autosave_association_test.rb
index 71c34d816a..04d5a2869c 100644
--- a/activerecord/test/cases/autosave_association_test.rb
+++ b/activerecord/test/cases/autosave_association_test.rb
@@ -774,13 +774,13 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   def test_should_destroy_has_many_as_part_of_the_save_transaction_if_they_were_marked_for_destruction
     2.times { |i| @pirate.birds.create!(:name => "birds_#{i}") }
 
-    assert !@pirate.birds.any? { |child| child.marked_for_destruction? }
+    assert !@pirate.birds.any?(&:marked_for_destruction?)
 
-    @pirate.birds.each { |child| child.mark_for_destruction }
+    @pirate.birds.each(&:mark_for_destruction)
     klass = @pirate.birds.first.class
     ids = @pirate.birds.map(&:id)
 
-    assert @pirate.birds.all? { |child| child.marked_for_destruction? }
+    assert @pirate.birds.all?(&:marked_for_destruction?)
     ids.each { |id| assert klass.find_by_id(id) }
 
     @pirate.save
@@ -814,14 +814,14 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     @pirate.birds.each { |bird| bird.name = '' }
     assert !@pirate.valid?
 
-    @pirate.birds.each { |bird| bird.destroy }
+    @pirate.birds.each(&:destroy)
     assert @pirate.valid?
   end
 
   def test_a_child_marked_for_destruction_should_not_be_destroyed_twice_while_saving_has_many
     @pirate.birds.create!(:name => "birds_1")
 
-    @pirate.birds.each { |bird| bird.mark_for_destruction }
+    @pirate.birds.each(&:mark_for_destruction)
     assert @pirate.save
 
     @pirate.birds.each { |bird| bird.expects(:destroy).never }
@@ -888,7 +888,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
       association_name_with_callbacks = "birds_with_#{callback_type}_callbacks"
 
       @pirate.send(association_name_with_callbacks).create!(:name => "Crowe the One-Eyed")
-      @pirate.send(association_name_with_callbacks).each { |c| c.mark_for_destruction }
+      @pirate.send(association_name_with_callbacks).each(&:mark_for_destruction)
       child_id = @pirate.send(association_name_with_callbacks).first.id
 
       @pirate.ship_log.clear
@@ -906,8 +906,8 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
   def test_should_destroy_habtm_as_part_of_the_save_transaction_if_they_were_marked_for_destruction
     2.times { |i| @pirate.parrots.create!(:name => "parrots_#{i}") }
 
-    assert !@pirate.parrots.any? { |parrot| parrot.marked_for_destruction? }
-    @pirate.parrots.each { |parrot| parrot.mark_for_destruction }
+    assert !@pirate.parrots.any?(&:marked_for_destruction?)
+    @pirate.parrots.each(&:mark_for_destruction)
 
     assert_no_difference "Parrot.count" do
       @pirate.save
@@ -940,14 +940,14 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
     @pirate.parrots.each { |parrot| parrot.name = '' }
     assert !@pirate.valid?
 
-    @pirate.parrots.each { |parrot| parrot.destroy }
+    @pirate.parrots.each(&:destroy)
     assert @pirate.valid?
   end
 
   def test_a_child_marked_for_destruction_should_not_be_destroyed_twice_while_saving_habtm
     @pirate.parrots.create!(:name => "parrots_1")
 
-    @pirate.parrots.each { |parrot| parrot.mark_for_destruction }
+    @pirate.parrots.each(&:mark_for_destruction)
     assert @pirate.save
 
     Pirate.transaction do
@@ -992,7 +992,7 @@ class TestDestroyAsPartOfAutosaveAssociation < ActiveRecord::TestCase
       association_name_with_callbacks = "parrots_with_#{callback_type}_callbacks"
 
       @pirate.send(association_name_with_callbacks).create!(:name => "Crowe the One-Eyed")
-      @pirate.send(association_name_with_callbacks).each { |c| c.mark_for_destruction }
+      @pirate.send(association_name_with_callbacks).each(&:mark_for_destruction)
       child_id = @pirate.send(association_name_with_callbacks).first.id
 
       @pirate.ship_log.clear
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 33a59d4678..a607c1319f 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -934,7 +934,7 @@ class FinderTest < ActiveRecord::TestCase
       joins('LEFT JOIN developers_projects ON developers.id = developers_projects.developer_id').
       where('project_id=1').to_a
     assert_equal 3, developers_on_project_one.length
-    developer_names = developers_on_project_one.map { |d| d.name }
+    developer_names = developers_on_project_one.map(&:name)
     assert developer_names.include?('David')
     assert developer_names.include?('Jamis')
   end
@@ -989,7 +989,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_select_values
-    assert_equal ["1","2","3","4","5","6","7","8","9", "10", "11"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map! { |i| i.to_s }
+    assert_equal ["1","2","3","4","5","6","7","8","9", "10", "11"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map!(&:to_s)
     assert_equal ["37signals","Summit","Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel", "Odegy", "Ex Nihilo Part Deux", "Apex"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
   end
 
@@ -1015,7 +1015,7 @@ class FinderTest < ActiveRecord::TestCase
       where(client_of: [2, 1, nil],
             name: ['37signals', 'Summit', 'Microsoft']).
       order('client_of DESC').
-      map { |x| x.client_of }
+      map(&:client_of)
 
     assert client_of.include?(nil)
     assert_equal [2, 1].sort, client_of.compact.sort
@@ -1025,7 +1025,7 @@ class FinderTest < ActiveRecord::TestCase
     client_of = Company.
       where(client_of: [nil]).
       order('client_of DESC').
-      map { |x| x.client_of }
+      map(&:client_of)
 
     assert_equal [], client_of.compact
   end
diff --git a/activerecord/test/cases/migration/column_positioning_test.rb b/activerecord/test/cases/migration/column_positioning_test.rb
index 77a752f050..62186e13a5 100644
--- a/activerecord/test/cases/migration/column_positioning_test.rb
+++ b/activerecord/test/cases/migration/column_positioning_test.rb
@@ -25,30 +25,30 @@ module ActiveRecord
 
       if current_adapter?(:MysqlAdapter, :Mysql2Adapter)
         def test_column_positioning
-          assert_equal %w(first second third), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(first second third), conn.columns(:testings).map(&:name)
         end
 
         def test_add_column_with_positioning
           conn.add_column :testings, :new_col, :integer
-          assert_equal %w(first second third new_col), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(first second third new_col), conn.columns(:testings).map(&:name)
         end
 
         def test_add_column_with_positioning_first
           conn.add_column :testings, :new_col, :integer, :first => true
-          assert_equal %w(new_col first second third), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(new_col first second third), conn.columns(:testings).map(&:name)
         end
 
         def test_add_column_with_positioning_after
           conn.add_column :testings, :new_col, :integer, :after => :first
-          assert_equal %w(first new_col second third), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(first new_col second third), conn.columns(:testings).map(&:name)
         end
 
         def test_change_column_with_positioning
           conn.change_column :testings, :second, :integer, :first => true
-          assert_equal %w(second first third), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(second first third), conn.columns(:testings).map(&:name)
 
           conn.change_column :testings, :second, :integer, :after => :third
-          assert_equal %w(first third second), conn.columns(:testings).map {|c| c.name }
+          assert_equal %w(first third second), conn.columns(:testings).map(&:name)
         end
       end
     end
diff --git a/activerecord/test/cases/migrator_test.rb b/activerecord/test/cases/migrator_test.rb
index f05ca900aa..c0daa83e9c 100644
--- a/activerecord/test/cases/migrator_test.rb
+++ b/activerecord/test/cases/migrator_test.rb
@@ -149,7 +149,7 @@ class MigratorTest < ActiveRecord::TestCase
   def test_up_calls_up
     migrations = [Sensor.new(nil, 0), Sensor.new(nil, 1), Sensor.new(nil, 2)]
     ActiveRecord::Migrator.new(:up, migrations).migrate
-    assert migrations.all? { |m| m.went_up }
+    assert migrations.all?(&:went_up)
     assert migrations.all? { |m| !m.went_down }
     assert_equal 2, ActiveRecord::Migrator.current_version
   end
@@ -160,7 +160,7 @@ class MigratorTest < ActiveRecord::TestCase
     migrations = [Sensor.new(nil, 0), Sensor.new(nil, 1), Sensor.new(nil, 2)]
     ActiveRecord::Migrator.new(:down, migrations).migrate
     assert migrations.all? { |m| !m.went_up }
-    assert migrations.all? { |m| m.went_down }
+    assert migrations.all?(&:went_down)
     assert_equal 0, ActiveRecord::Migrator.current_version
   end
 
diff --git a/activerecord/test/cases/nested_attributes_test.rb b/activerecord/test/cases/nested_attributes_test.rb
index cf96c3fccf..5c7e8a65d2 100644
--- a/activerecord/test/cases/nested_attributes_test.rb
+++ b/activerecord/test/cases/nested_attributes_test.rb
@@ -13,7 +13,7 @@ require 'active_support/hash_with_indifferent_access'
 
 class TestNestedAttributesInGeneral < ActiveRecord::TestCase
   teardown do
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
   end
 
   def test_base_should_have_an_empty_nested_attributes_options
@@ -300,13 +300,13 @@ class TestNestedAttributesOnAHasOneAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_destroy_an_existing_record_if_allow_destroy_is_false
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => false, :reject_if => proc { |attributes| attributes.empty? }
+    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => false, :reject_if => proc(&:empty?)
 
     @pirate.update(ship_attributes: { id: @pirate.ship.id, _destroy: '1' })
 
     assert_equal @ship, @pirate.reload.ship
 
-    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+    Pirate.accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
   end
 
   def test_should_also_work_with_a_HashWithIndifferentAccess
@@ -494,12 +494,12 @@ class TestNestedAttributesOnABelongsToAssociation < ActiveRecord::TestCase
   end
 
   def test_should_not_destroy_an_existing_record_if_allow_destroy_is_false
-    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => false, :reject_if => proc { |attributes| attributes.empty? }
+    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => false, :reject_if => proc(&:empty?)
 
     @ship.update(pirate_attributes: { id: @ship.pirate.id, _destroy: '1' })
     assert_nothing_raised(ActiveRecord::RecordNotFound) { @ship.pirate.reload }
   ensure
-    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+    Ship.accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc(&:empty?)
   end
 
   def test_should_work_with_update_as_well
@@ -855,7 +855,7 @@ end
 
 module NestedAttributesLimitTests
   def teardown
-    Pirate.accepts_nested_attributes_for :parrots, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+    Pirate.accepts_nested_attributes_for :parrots, :allow_destroy => true, :reject_if => proc(&:empty?)
   end
 
   def test_limit_with_less_records
diff --git a/activerecord/test/cases/persistence_test.rb b/activerecord/test/cases/persistence_test.rb
index 2bcd496415..6fc4731f01 100644
--- a/activerecord/test/cases/persistence_test.rb
+++ b/activerecord/test/cases/persistence_test.rb
@@ -127,7 +127,7 @@ class PersistenceTest < ActiveRecord::TestCase
     assert_difference('Topic.count', -topics_by_mary.size) do
       destroyed = Topic.destroy_all(conditions).sort_by(&:id)
       assert_equal topics_by_mary, destroyed
-      assert destroyed.all? { |topic| topic.frozen? }, "destroyed topics should be frozen"
+      assert destroyed.all?(&:frozen?), "destroyed topics should be frozen"
     end
   end
 
@@ -137,7 +137,7 @@ class PersistenceTest < ActiveRecord::TestCase
     assert_difference('Client.count', -2) do
       destroyed = Client.destroy([2, 3]).sort_by(&:id)
       assert_equal clients, destroyed
-      assert destroyed.all? { |client| client.frozen? }, "destroyed clients should be frozen"
+      assert destroyed.all?(&:frozen?), "destroyed clients should be frozen"
     end
   end
 
diff --git a/activerecord/test/cases/pooled_connections_test.rb b/activerecord/test/cases/pooled_connections_test.rb
index 8eea10143f..98888150a8 100644
--- a/activerecord/test/cases/pooled_connections_test.rb
+++ b/activerecord/test/cases/pooled_connections_test.rb
@@ -13,7 +13,7 @@ class PooledConnectionsTest < ActiveRecord::TestCase
   teardown do
     ActiveRecord::Base.clear_all_connections!
     ActiveRecord::Base.establish_connection(@connection)
-    @per_test_teardown.each {|td| td.call }
+    @per_test_teardown.each(&:call)
   end
 
   # Will deadlock due to lack of Monitor timeouts in 1.9
diff --git a/activerecord/test/cases/reflection_test.rb b/activerecord/test/cases/reflection_test.rb
index 094fcccc89..e86b892a0a 100644
--- a/activerecord/test/cases/reflection_test.rb
+++ b/activerecord/test/cases/reflection_test.rb
@@ -50,13 +50,13 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_columns_are_returned_in_the_order_they_were_declared
-    column_names = Topic.columns.map { |column| column.name }
+    column_names = Topic.columns.map(&:name)
     assert_equal %w(id title author_name author_email_address written_on bonus_time last_read content important approved replies_count unique_replies_count parent_id parent_title type group created_at updated_at), column_names
   end
 
   def test_content_columns
     content_columns        = Topic.content_columns
-    content_column_names   = content_columns.map {|column| column.name}
+    content_column_names   = content_columns.map(&:name)
     assert_equal 13, content_columns.length
     assert_equal %w(title author_name author_email_address written_on bonus_time last_read content important group approved parent_title created_at updated_at).sort, content_column_names.sort
   end
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index ca86d58b35..fc9637a167 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -249,7 +249,7 @@ class RelationTest < ActiveRecord::TestCase
 
   def test_finding_with_reorder
     topics = Topic.order('author_name').order('title').reorder('id').to_a
-    topics_titles = topics.map{ |t| t.title }
+    topics_titles = topics.map(&:title)
     assert_equal ['The First Topic', 'The Second Topic of the day', 'The Third Topic of the day', 'The Fourth Topic of the day', 'The Fifth Topic of the day'], topics_titles
   end
 
@@ -441,7 +441,7 @@ class RelationTest < ActiveRecord::TestCase
       where('project_id=1').to_a
 
     assert_equal 3, developers_on_project_one.length
-    developer_names = developers_on_project_one.map { |d| d.name }
+    developer_names = developers_on_project_one.map(&:name)
     assert developer_names.include?('David')
     assert developer_names.include?('Jamis')
   end
@@ -652,8 +652,8 @@ class RelationTest < ActiveRecord::TestCase
     expected_taggings = taggings(:welcome_general, :thinking_general)
 
     assert_no_queries do
-      assert_equal expected_taggings, author.taggings.distinct.sort_by { |t| t.id }
-      assert_equal expected_taggings, author.taggings.uniq.sort_by { |t| t.id }
+      assert_equal expected_taggings, author.taggings.distinct.sort_by(&:id)
+      assert_equal expected_taggings, author.taggings.uniq.sort_by(&:id)
     end
 
     authors = Author.all
diff --git a/activerecord/test/cases/scoping/default_scoping_test.rb b/activerecord/test/cases/scoping/default_scoping_test.rb
index 880d0e8293..5bdebe6ac7 100644
--- a/activerecord/test/cases/scoping/default_scoping_test.rb
+++ b/activerecord/test/cases/scoping/default_scoping_test.rb
@@ -8,8 +8,8 @@ class DefaultScopingTest < ActiveRecord::TestCase
   fixtures :developers, :posts, :comments
 
   def test_default_scope
-    expected = Developer.all.merge!(:order => 'salary DESC').to_a.collect { |dev| dev.salary }
-    received = DeveloperOrderedBySalary.all.collect { |dev| dev.salary }
+    expected = Developer.all.merge!(:order => 'salary DESC').to_a.collect(&:salary)
+    received = DeveloperOrderedBySalary.all.collect(&:salary)
     assert_equal expected, received
   end
 
@@ -86,14 +86,14 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_scope_overwrites_default
-    expected = Developer.all.merge!(order: 'salary DESC, name DESC').to_a.collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.by_name.to_a.collect { |dev| dev.name }
+    expected = Developer.all.merge!(order: 'salary DESC, name DESC').to_a.collect(&:name)
+    received = DeveloperOrderedBySalary.by_name.to_a.collect(&:name)
     assert_equal expected, received
   end
 
   def test_reorder_overrides_default_scope_order
-    expected = Developer.order('name DESC').collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.reorder('name DESC').collect { |dev| dev.name }
+    expected = Developer.order('name DESC').collect(&:name)
+    received = DeveloperOrderedBySalary.reorder('name DESC').collect(&:name)
     assert_equal expected, received
   end
 
@@ -146,34 +146,34 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_unscope_multiple_where_clauses
-    expected = Developer.order('salary DESC').collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.where(name: 'Jamis').where(id: 1).unscope(where: [:name, :id]).collect { |dev| dev.name }
+    expected = Developer.order('salary DESC').collect(&:name)
+    received = DeveloperOrderedBySalary.where(name: 'Jamis').where(id: 1).unscope(where: [:name, :id]).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_string_where_clauses_involved
     dev_relation = Developer.order('salary DESC').where("created_at > ?", 1.year.ago)
-    expected = dev_relation.collect { |dev| dev.name }
+    expected = dev_relation.collect(&:name)
 
     dev_ordered_relation = DeveloperOrderedBySalary.where(name: 'Jamis').where("created_at > ?", 1.year.ago)
-    received = dev_ordered_relation.unscope(where: [:name]).collect { |dev| dev.name }
+    received = dev_ordered_relation.unscope(where: [:name]).collect(&:name)
 
     assert_equal expected, received
   end
 
   def test_unscope_with_grouping_attributes
-    expected = Developer.order('salary DESC').collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.group(:name).unscope(:group).collect { |dev| dev.name }
+    expected = Developer.order('salary DESC').collect(&:name)
+    received = DeveloperOrderedBySalary.group(:name).unscope(:group).collect(&:name)
     assert_equal expected, received
 
-    expected_2 = Developer.order('salary DESC').collect { |dev| dev.name }
-    received_2 = DeveloperOrderedBySalary.group("name").unscope(:group).collect { |dev| dev.name }
+    expected_2 = Developer.order('salary DESC').collect(&:name)
+    received_2 = DeveloperOrderedBySalary.group("name").unscope(:group).collect(&:name)
     assert_equal expected_2, received_2
   end
 
   def test_unscope_with_limit_in_query
-    expected = Developer.order('salary DESC').collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.limit(1).unscope(:limit).collect { |dev| dev.name }
+    expected = Developer.order('salary DESC').collect(&:name)
+    received = DeveloperOrderedBySalary.limit(1).unscope(:limit).collect(&:name)
     assert_equal expected, received
   end
 
@@ -183,42 +183,42 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_unscope_reverse_order
-    expected = Developer.all.collect { |dev| dev.name }
-    received = Developer.order('salary DESC').reverse_order.unscope(:order).collect { |dev| dev.name }
+    expected = Developer.all.collect(&:name)
+    received = Developer.order('salary DESC').reverse_order.unscope(:order).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_select
-    expected = Developer.order('salary ASC').collect { |dev| dev.name }
-    received = Developer.order('salary DESC').reverse_order.select(:name).unscope(:select).collect { |dev| dev.name }
+    expected = Developer.order('salary ASC').collect(&:name)
+    received = Developer.order('salary DESC').reverse_order.select(:name).unscope(:select).collect(&:name)
     assert_equal expected, received
 
-    expected_2 = Developer.all.collect { |dev| dev.id }
-    received_2 = Developer.select(:name).unscope(:select).collect { |dev| dev.id }
+    expected_2 = Developer.all.collect(&:id)
+    received_2 = Developer.select(:name).unscope(:select).collect(&:id)
     assert_equal expected_2, received_2
   end
 
   def test_unscope_offset
-    expected = Developer.all.collect { |dev| dev.name }
-    received = Developer.offset(5).unscope(:offset).collect { |dev| dev.name }
+    expected = Developer.all.collect(&:name)
+    received = Developer.offset(5).unscope(:offset).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_joins_and_select_on_developers_projects
-    expected = Developer.all.collect { |dev| dev.name }
-    received = Developer.joins('JOIN developers_projects ON id = developer_id').select(:id).unscope(:joins, :select).collect { |dev| dev.name }
+    expected = Developer.all.collect(&:name)
+    received = Developer.joins('JOIN developers_projects ON id = developer_id').select(:id).unscope(:joins, :select).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_includes
-    expected = Developer.all.collect { |dev| dev.name }
-    received = Developer.includes(:projects).select(:id).unscope(:includes, :select).collect { |dev| dev.name }
+    expected = Developer.all.collect(&:name)
+    received = Developer.includes(:projects).select(:id).unscope(:includes, :select).collect(&:name)
     assert_equal expected, received
   end
 
   def test_unscope_having
-    expected = DeveloperOrderedBySalary.all.collect { |dev| dev.name }
-    received = DeveloperOrderedBySalary.having("name IN ('Jamis', 'David')").unscope(:having).collect { |dev| dev.name }
+    expected = DeveloperOrderedBySalary.all.collect(&:name)
+    received = DeveloperOrderedBySalary.having("name IN ('Jamis', 'David')").unscope(:having).collect(&:name)
     assert_equal expected, received
   end
 
@@ -281,8 +281,8 @@ class DefaultScopingTest < ActiveRecord::TestCase
   end
 
   def test_order_in_default_scope_should_not_prevail
-    expected = Developer.all.merge!(order: 'salary desc').to_a.collect { |dev| dev.salary }
-    received = DeveloperOrderedBySalary.all.merge!(order: 'salary').to_a.collect { |dev| dev.salary }
+    expected = Developer.all.merge!(order: 'salary desc').to_a.collect(&:salary)
+    received = DeveloperOrderedBySalary.all.merge!(order: 'salary').to_a.collect(&:salary)
     assert_equal expected, received
   end
 
diff --git a/activerecord/test/cases/test_case.rb b/activerecord/test/cases/test_case.rb
index eb44c4a83c..5ba17359f0 100644
--- a/activerecord/test/cases/test_case.rb
+++ b/activerecord/test/cases/test_case.rb
@@ -43,7 +43,7 @@ module ActiveRecord
       patterns_to_match.each do |pattern|
         failed_patterns << pattern unless SQLCounter.log_all.any?{ |sql| pattern === sql }
       end
-      assert failed_patterns.empty?, "Query pattern(s) #{failed_patterns.map{ |p| p.inspect }.join(', ')} not found.#{SQLCounter.log.size == 0 ? '' : "\nQueries:\n#{SQLCounter.log.join("\n")}"}"
+      assert failed_patterns.empty?, "Query pattern(s) #{failed_patterns.map(&:inspect).join(', ')} not found.#{SQLCounter.log.size == 0 ? '' : "\nQueries:\n#{SQLCounter.log.join("\n")}"}"
     end
 
     def assert_queries(num = 1, options = {})
diff --git a/activerecord/test/cases/transactions_test.rb b/activerecord/test/cases/transactions_test.rb
index 7160e8324d..72c07d8aea 100644
--- a/activerecord/test/cases/transactions_test.rb
+++ b/activerecord/test/cases/transactions_test.rb
@@ -13,7 +13,7 @@ class TransactionTest < ActiveRecord::TestCase
   fixtures :topics, :developers, :authors, :posts
 
   def setup
-    @first, @second = Topic.find(1, 2).sort_by { |t| t.id }
+    @first, @second = Topic.find(1, 2).sort_by(&:id)
   end
 
   def test_persisted_in_a_model_with_custom_primary_key_after_failed_save
@@ -699,7 +699,7 @@ if current_adapter?(:PostgreSQLAdapter)
           end
         end
 
-        threads.each { |t| t.join }
+        threads.each(&:join)
       end
     end
 
@@ -747,7 +747,7 @@ if current_adapter?(:PostgreSQLAdapter)
           Developer.connection.close
         end
 
-        threads.each { |t| t.join }
+        threads.each(&:join)
       end
 
       assert_equal original_salary, Developer.find(1).salary
diff --git a/activerecord/test/cases/validations_repair_helper.rb b/activerecord/test/cases/validations_repair_helper.rb
index 2bbf0f23b3..b30666d876 100644
--- a/activerecord/test/cases/validations_repair_helper.rb
+++ b/activerecord/test/cases/validations_repair_helper.rb
@@ -5,9 +5,7 @@ module ActiveRecord
     module ClassMethods
       def repair_validations(*model_classes)
         teardown do
-          model_classes.each do |k|
-            k.clear_validators!
-          end
+          model_classes.each(&:clear_validators!)
         end
       end
     end
@@ -15,9 +13,7 @@ module ActiveRecord
     def repair_validations(*model_classes)
       yield if block_given?
     ensure
-      model_classes.each do |k|
-        k.clear_validators!
-      end
+      model_classes.each(&:clear_validators!)
     end
   end
 end
diff --git a/activerecord/test/models/customer.rb b/activerecord/test/models/customer.rb
index 7e8e82542f..afe4b3d707 100644
--- a/activerecord/test/models/customer.rb
+++ b/activerecord/test/models/customer.rb
@@ -2,7 +2,7 @@ class Customer < ActiveRecord::Base
   cattr_accessor :gps_conversion_was_run
 
   composed_of :address, :mapping => [ %w(address_street street), %w(address_city city), %w(address_country country) ], :allow_nil => true
-  composed_of :balance, :class_name => "Money", :mapping => %w(balance amount), :converter => Proc.new { |balance| balance.to_money }
+  composed_of :balance, :class_name => "Money", :mapping => %w(balance amount), :converter => Proc.new(&:to_money)
   composed_of :gps_location, :allow_nil => true
   composed_of :non_blank_gps_location, :class_name => "GpsLocation", :allow_nil => true, :mapping => %w(gps_location gps_location),
               :converter => lambda { |gps| self.gps_conversion_was_run = true; gps.blank? ? nil : GpsLocation.new(gps)}
diff --git a/activerecord/test/models/pirate.rb b/activerecord/test/models/pirate.rb
index 90a3c3ecee..641a33f9be 100644
--- a/activerecord/test/models/pirate.rb
+++ b/activerecord/test/models/pirate.rb
@@ -36,8 +36,8 @@ class Pirate < ActiveRecord::Base
 
   has_one :foo_bulb, -> { where :name => 'foo' }, :foreign_key => :car_id, :class_name => "Bulb"
 
-  accepts_nested_attributes_for :parrots, :birds, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
-  accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+  accepts_nested_attributes_for :parrots, :birds, :allow_destroy => true, :reject_if => proc(&:empty?)
+  accepts_nested_attributes_for :ship, :allow_destroy => true, :reject_if => proc(&:empty?)
   accepts_nested_attributes_for :update_only_ship, :update_only => true
   accepts_nested_attributes_for :parrots_with_method_callbacks, :parrots_with_proc_callbacks,
     :birds_with_method_callbacks, :birds_with_proc_callbacks, :allow_destroy => true
diff --git a/activerecord/test/models/ship.rb b/activerecord/test/models/ship.rb
index 77a4728d0b..5f618a50d2 100644
--- a/activerecord/test/models/ship.rb
+++ b/activerecord/test/models/ship.rb
@@ -6,7 +6,7 @@ class Ship < ActiveRecord::Base
   has_many :parts, :class_name => 'ShipPart'
 
   accepts_nested_attributes_for :parts, :allow_destroy => true
-  accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc { |attributes| attributes.empty? }
+  accepts_nested_attributes_for :pirate, :allow_destroy => true, :reject_if => proc(&:empty?)
   accepts_nested_attributes_for :update_only_pirate, :update_only => true
 
   validates_presence_of :name
diff --git a/activesupport/bin/generate_tables b/activesupport/bin/generate_tables
index f39e89b7d0..71a6b78652 100755
--- a/activesupport/bin/generate_tables
+++ b/activesupport/bin/generate_tables
@@ -55,7 +55,7 @@ module ActiveSupport
           codepoint.combining_class   = Integer($4)
           #codepoint.bidi_class        = $5
           codepoint.decomp_type       = $7
-          codepoint.decomp_mapping    = ($8=='') ? nil : $8.split.collect { |element| element.hex }
+          codepoint.decomp_mapping    = ($8=='') ? nil : $8.split.collect(&:hex)
           #codepoint.bidi_mirrored     = ($13=='Y') ? true : false
           codepoint.uppercase_mapping = ($16=='') ? 0 : $16.hex
           codepoint.lowercase_mapping = ($17=='') ? 0 : $17.hex
diff --git a/activesupport/lib/active_support/core_ext/array/conversions.rb b/activesupport/lib/active_support/core_ext/array/conversions.rb
index 76ffd23ed1..080e3b5ef7 100644
--- a/activesupport/lib/active_support/core_ext/array/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/array/conversions.rb
@@ -92,7 +92,7 @@ class Array
       if empty?
         'null'
       else
-        collect { |element| element.id }.join(',')
+        collect(&:id).join(',')
       end
     else
       to_default_s
diff --git a/activesupport/lib/active_support/core_ext/hash/keys.rb b/activesupport/lib/active_support/core_ext/hash/keys.rb
index f4105f66b0..9297a59c46 100644
--- a/activesupport/lib/active_support/core_ext/hash/keys.rb
+++ b/activesupport/lib/active_support/core_ext/hash/keys.rb
@@ -31,13 +31,13 @@ class Hash
   #   hash.stringify_keys
   #   # => {"name"=>"Rob", "age"=>"28"}
   def stringify_keys
-    transform_keys{ |key| key.to_s }
+    transform_keys(&:to_s)
   end
 
   # Destructively convert all keys to strings. Same as
   # +stringify_keys+, but modifies +self+.
   def stringify_keys!
-    transform_keys!{ |key| key.to_s }
+    transform_keys!(&:to_s)
   end
 
   # Returns a new hash with all keys converted to symbols, as long as
@@ -105,14 +105,14 @@ class Hash
   #   hash.deep_stringify_keys
   #   # => {"person"=>{"name"=>"Rob", "age"=>"28"}}
   def deep_stringify_keys
-    deep_transform_keys{ |key| key.to_s }
+    deep_transform_keys(&:to_s)
   end
 
   # Destructively convert all keys to strings.
   # This includes the keys from the root hash and from all
   # nested hashes and arrays.
   def deep_stringify_keys!
-    deep_transform_keys!{ |key| key.to_s }
+    deep_transform_keys!(&:to_s)
   end
 
   # Returns a new hash with all keys converted to symbols, as long as
diff --git a/activesupport/lib/active_support/core_ext/object/deep_dup.rb b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
index 2e99f4a1b8..0191d2e973 100644
--- a/activesupport/lib/active_support/core_ext/object/deep_dup.rb
+++ b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
@@ -25,7 +25,7 @@ class Array
   #   array[1][2] # => nil
   #   dup[1][2]   # => 4
   def deep_dup
-    map { |it| it.deep_dup }
+    map(&:deep_dup)
   end
 end
 
diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
index 755e1c6b16..593a7a4940 100644
--- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb
+++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
@@ -23,6 +23,6 @@ class Object
   #
   #   C.new(0, 1).instance_variable_names # => ["@y", "@x"]
   def instance_variable_names
-    instance_variables.map { |var| var.to_s }
+    instance_variables.map(&:to_s)
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/object/to_query.rb b/activesupport/lib/active_support/core_ext/object/to_query.rb
index ccd568bbf5..ec5ace4e16 100644
--- a/activesupport/lib/active_support/core_ext/object/to_query.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_query.rb
@@ -38,7 +38,7 @@ class Array
   # Calls <tt>to_param</tt> on all its elements and joins the result with
   # slashes. This is used by <tt>url_for</tt> in Action Pack.
   def to_param
-    collect { |e| e.to_param }.join '/'
+    collect(&:to_param).join '/'
   end
 
   # Converts an array into a string suitable for use as a URL query string,
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index 65a370dd30..ff8c0fd310 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -742,7 +742,7 @@ module ActiveSupport #:nodoc:
     protected
       def log_call(*args)
         if log_activity?
-          arg_str = args.collect { |arg| arg.inspect } * ', '
+          arg_str = args.collect(&:inspect) * ', '
           /in `([a-z_\?\!]+)'/ =~ caller(1).first
           selector = $1 || '<unknown>'
           log "called #{selector}(#{arg_str})"
diff --git a/activesupport/lib/active_support/number_helper/number_to_human_converter.rb b/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
index 9a3dc526ae..6940beb318 100644
--- a/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
+++ b/activesupport/lib/active_support/number_helper/number_to_human_converter.rb
@@ -59,7 +59,7 @@ module ActiveSupport
             translate_in_locale("human.decimal_units.units", raise: true)
           else
             raise ArgumentError, ":units must be a Hash or String translation scope."
-          end.keys.map { |e_name| INVERTED_DECIMAL_UNITS[e_name] }.sort_by { |e| -e }
+          end.keys.map { |e_name| INVERTED_DECIMAL_UNITS[e_name] }.sort_by(&:-@)
         end
     end
   end
diff --git a/activesupport/lib/active_support/testing/assertions.rb b/activesupport/lib/active_support/testing/assertions.rb
index 11cca82995..8b649c193f 100644
--- a/activesupport/lib/active_support/testing/assertions.rb
+++ b/activesupport/lib/active_support/testing/assertions.rb
@@ -66,7 +66,7 @@ module ActiveSupport
         exps = expressions.map { |e|
           e.respond_to?(:call) ? e : lambda { eval(e, block.binding) }
         }
-        before = exps.map { |e| e.call }
+        before = exps.map(&:call)
 
         yield
 
diff --git a/activesupport/lib/active_support/values/time_zone.rb b/activesupport/lib/active_support/values/time_zone.rb
index 55533a5d40..fd05a5459c 100644
--- a/activesupport/lib/active_support/values/time_zone.rb
+++ b/activesupport/lib/active_support/values/time_zone.rb
@@ -237,7 +237,7 @@ module ActiveSupport
         case arg
           when String
           begin
-            @lazy_zones_map[arg] ||= create(arg).tap { |tz| tz.utc_offset }
+            @lazy_zones_map[arg] ||= create(arg).tap(&:utc_offset)
           rescue TZInfo::InvalidTimezoneIdentifier
             nil
           end
diff --git a/activesupport/test/core_ext/enumerable_test.rb b/activesupport/test/core_ext/enumerable_test.rb
index 6fcf6e8743..346dc3d208 100644
--- a/activesupport/test/core_ext/enumerable_test.rb
+++ b/activesupport/test/core_ext/enumerable_test.rb
@@ -71,14 +71,14 @@ class EnumerableTests < ActiveSupport::TestCase
   def test_index_by
     payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
     assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
-                 payments.index_by { |p| p.price })
+                 payments.index_by(&:price))
     assert_equal Enumerator, payments.index_by.class
     if Enumerator.method_defined? :size
       assert_equal nil, payments.index_by.size
       assert_equal 42, (1..42).index_by.size
     end
     assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
-                 payments.index_by.each { |p| p.price })
+                 payments.index_by.each(&:price))
   end
 
   def test_many
diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index 5e9fdfd872..3d2f50ce49 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -365,7 +365,7 @@ class HashExtTest < ActiveSupport::TestCase
       :member? => true }
 
     hashes.each do |name, hash|
-      method_map.sort_by { |m| m.to_s }.each do |meth, expected|
+      method_map.sort_by(&:to_s).each do |meth, expected|
         assert_equal(expected, hash.__send__(meth, 'a'),
                      "Calling #{name}.#{meth} 'a'")
         assert_equal(expected, hash.__send__(meth, :a),
diff --git a/activesupport/test/core_ext/object/try_test.rb b/activesupport/test/core_ext/object/try_test.rb
index efc6beaf02..89438675c1 100644
--- a/activesupport/test/core_ext/object/try_test.rb
+++ b/activesupport/test/core_ext/object/try_test.rb
@@ -52,11 +52,11 @@ class ObjectTryTest < ActiveSupport::TestCase
   end
 
   def test_try_only_block
-    assert_equal @string.reverse, @string.try { |s| s.reverse }
+    assert_equal @string.reverse, @string.try(&:reverse)
   end
 
   def test_try_only_block_bang
-    assert_equal @string.reverse, @string.try! { |s| s.reverse }
+    assert_equal @string.reverse, @string.try!(&:reverse)
   end
 
   def test_try_only_block_nil
diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index e32c178951..0af207fae9 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -281,15 +281,11 @@ class StringInflectionsTest < ActiveSupport::TestCase
   end
 
   def test_constantize
-    run_constantize_tests_on do |string|
-      string.constantize
-    end
+    run_constantize_tests_on(&:constantize)
   end
 
   def test_safe_constantize
-    run_safe_constantize_tests_on do |string|
-      string.safe_constantize
-    end
+    run_safe_constantize_tests_on(&:safe_constantize)
   end
 end
 
diff --git a/activesupport/test/multibyte_chars_test.rb b/activesupport/test/multibyte_chars_test.rb
index feca013675..94748dd991 100644
--- a/activesupport/test/multibyte_chars_test.rb
+++ b/activesupport/test/multibyte_chars_test.rb
@@ -182,7 +182,7 @@ class MultibyteCharsUTF8BehaviourTest < ActiveSupport::TestCase
   end
 
   def test_sortability
-    words = %w(builder armor zebra).sort_by { |s| s.mb_chars }
+    words = %w(builder armor zebra).sort_by(&:mb_chars)
     assert_equal %w(armor builder zebra), words
   end
 
diff --git a/activesupport/test/multibyte_conformance_test.rb b/activesupport/test/multibyte_conformance_test.rb
index aba81b8248..f7bd21c8ab 100644
--- a/activesupport/test/multibyte_conformance_test.rb
+++ b/activesupport/test/multibyte_conformance_test.rb
@@ -115,7 +115,7 @@ class MultibyteConformanceTest < ActiveSupport::TestCase
           next if (line.empty? || line =~ /^\#/)
 
           cols, comment = line.split("#")
-          cols = cols.split(";").map{|e| e.strip}.reject{|e| e.empty? }
+          cols = cols.split(";").map(&:strip).reject(&:empty?)
           next unless cols.length == 5
 
           # codepoints are in hex in the test suite, pack wants them as integers
diff --git a/activesupport/test/rescuable_test.rb b/activesupport/test/rescuable_test.rb
index ec9d231125..b8af888f7c 100644
--- a/activesupport/test/rescuable_test.rb
+++ b/activesupport/test/rescuable_test.rb
@@ -93,13 +93,13 @@ class RescuableTest < ActiveSupport::TestCase
 
   def test_rescues_defined_later_are_added_at_end_of_the_rescue_handlers_array
     expected = ["WraithAttack", "WraithAttack", "NuclearExplosion", "MadRonon"]
-    result = @stargate.send(:rescue_handlers).collect {|e| e.first}
+    result = @stargate.send(:rescue_handlers).collect(&:first)
     assert_equal expected, result
   end
 
   def test_children_should_inherit_rescue_definitions_from_parents_and_child_rescue_should_be_appended
     expected = ["WraithAttack", "WraithAttack", "NuclearExplosion", "MadRonon", "CoolError"]
-    result = @cool_stargate.send(:rescue_handlers).collect {|e| e.first}
+    result = @cool_stargate.send(:rescue_handlers).collect(&:first)
     assert_equal expected, result
   end
 end
diff --git a/ci/travis.rb b/ci/travis.rb
index a1920a7a1f..b62f90a59e 100755
--- a/ci/travis.rb
+++ b/ci/travis.rb
@@ -140,6 +140,6 @@ if failures.empty?
 else
   puts
   puts "Rails build FAILED"
-  puts "Failed components: #{failures.map { |component| component.first }.join(', ')}"
+  puts "Failed components: #{failures.map(&:first).join(', ')}"
   exit(false)
 end
diff --git a/guides/rails_guides/kindle.rb b/guides/rails_guides/kindle.rb
index 09eecd5634..32926622e3 100644
--- a/guides/rails_guides/kindle.rb
+++ b/guides/rails_guides/kindle.rb
@@ -70,7 +70,7 @@ module Kindle
       File.open("sections/%03d/_section.txt" % section_idx, 'w') {|f| f.puts title}
       doc.xpath("//h3[@id]").each_with_index do |h3,item_idx|
         subsection = h3.inner_text
-        content = h3.xpath("./following-sibling::*").take_while {|x| x.name != "h3"}.map {|x| x.to_html}
+        content = h3.xpath("./following-sibling::*").take_while {|x| x.name != "h3"}.map(&:to_html)
         item = Nokogiri::HTML(h3.to_html + content.join("\n"))
         item_path = "sections/%03d/%03d.html" % [section_idx, item_idx] 
         add_head_section(item, subsection)
diff --git a/railties/lib/rails/application/routes_reloader.rb b/railties/lib/rails/application/routes_reloader.rb
index 737977adf9..cf0a4e128f 100644
--- a/railties/lib/rails/application/routes_reloader.rb
+++ b/railties/lib/rails/application/routes_reloader.rb
@@ -41,9 +41,7 @@ module Rails
       end
 
       def finalize!
-        route_sets.each do |routes|
-          routes.finalize!
-        end
+        route_sets.each(&:finalize!)
       end
 
       def revert
diff --git a/railties/lib/rails/commands/plugin.rb b/railties/lib/rails/commands/plugin.rb
index 95bbdd4cdf..52d8966ead 100644
--- a/railties/lib/rails/commands/plugin.rb
+++ b/railties/lib/rails/commands/plugin.rb
@@ -11,7 +11,7 @@ else
               end
     if File.exist?(railsrc)
       extra_args_string = File.read(railsrc)
-      extra_args = extra_args_string.split(/\n+/).flat_map {|l| l.split}
+      extra_args = extra_args_string.split(/\n+/).flat_map(&:split)
       puts "Using #{extra_args.join(" ")} from #{railsrc}"
       ARGV.insert(1, *extra_args)
     end
diff --git a/railties/lib/rails/generators.rb b/railties/lib/rails/generators.rb
index bf2390cb7e..e25c364178 100644
--- a/railties/lib/rails/generators.rb
+++ b/railties/lib/rails/generators.rb
@@ -153,7 +153,7 @@ module Rails
     def self.invoke(namespace, args=ARGV, config={})
       names = namespace.to_s.split(':')
       if klass = find_by_namespace(names.pop, names.any? && names.join(':'))
-        args << "--help" if args.empty? && klass.arguments.any? { |a| a.required? }
+        args << "--help" if args.empty? && klass.arguments.any?(&:required?)
         klass.start(args, config)
       else
         options     = sorted_groups.map(&:last).flatten
@@ -226,7 +226,7 @@ module Rails
 
     def self.public_namespaces
       lookup!
-      subclasses.map { |k| k.namespace }
+      subclasses.map(&:namespace)
     end
 
     def self.print_generators
diff --git a/railties/lib/rails/generators/actions.rb b/railties/lib/rails/generators/actions.rb
index ffdb314612..5373121835 100644
--- a/railties/lib/rails/generators/actions.rb
+++ b/railties/lib/rails/generators/actions.rb
@@ -189,7 +189,7 @@ module Rails
       #   generate(:authenticated, "user session")
       def generate(what, *args)
         log :generate, what
-        argument = args.flat_map {|arg| arg.to_s }.join(" ")
+        argument = args.flat_map(&:to_s).join(" ")
 
         in_root { run_ruby_script("bin/rails generate #{what} #{argument}", verbose: false) }
       end
diff --git a/railties/lib/rails/generators/base.rb b/railties/lib/rails/generators/base.rb
index 9af6435f23..813b8b629e 100644
--- a/railties/lib/rails/generators/base.rb
+++ b/railties/lib/rails/generators/base.rb
@@ -273,7 +273,7 @@ module Rails
 
         # Use Rails default banner.
         def self.banner
-          "rails generate #{namespace.sub(/^rails:/,'')} #{self.arguments.map{ |a| a.usage }.join(' ')} [options]".gsub(/\s+/, ' ')
+          "rails generate #{namespace.sub(/^rails:/,'')} #{self.arguments.map(&:usage).join(' ')} [options]".gsub(/\s+/, ' ')
         end
 
         # Sets the base_name taking into account the current class namespace.
diff --git a/railties/lib/rails/generators/named_base.rb b/railties/lib/rails/generators/named_base.rb
index b7da44ca2d..397e1e73f1 100644
--- a/railties/lib/rails/generators/named_base.rb
+++ b/railties/lib/rails/generators/named_base.rb
@@ -99,7 +99,7 @@ module Rails
         end
 
         def class_name
-          (class_path + [file_name]).map!{ |m| m.camelize }.join('::')
+          (class_path + [file_name]).map!(&:camelize).join('::')
         end
 
         def human_name
@@ -156,7 +156,7 @@ module Rails
 
         def assign_names!(name) #:nodoc:
           @class_path = name.include?('/') ? name.split('/') : name.split('::')
-          @class_path.map! { |m| m.underscore }
+          @class_path.map!(&:underscore)
           @file_name = @class_path.pop
         end
 
diff --git a/railties/lib/rails/generators/rails/app/app_generator.rb b/railties/lib/rails/generators/rails/app/app_generator.rb
index 9110c129d1..f8a8ae90d9 100644
--- a/railties/lib/rails/generators/rails/app/app_generator.rb
+++ b/railties/lib/rails/generators/rails/app/app_generator.rb
@@ -260,9 +260,7 @@ module Rails
       public_task :generate_spring_binstubs
 
       def run_after_bundle_callbacks
-        @after_bundle_callbacks.each do |callback|
-          callback.call
-        end
+        @after_bundle_callbacks.each(&:call)
       end
 
     protected
diff --git a/railties/lib/rails/generators/resource_helpers.rb b/railties/lib/rails/generators/resource_helpers.rb
index 4669935156..3f84d76ae0 100644
--- a/railties/lib/rails/generators/resource_helpers.rb
+++ b/railties/lib/rails/generators/resource_helpers.rb
@@ -39,7 +39,7 @@ module Rails
         def assign_controller_names!(name)
           @controller_name = name
           @controller_class_path = name.include?('/') ? name.split('/') : name.split('::')
-          @controller_class_path.map! { |m| m.underscore }
+          @controller_class_path.map!(&:underscore)
           @controller_file_name = @controller_class_path.pop
         end
 
@@ -48,7 +48,7 @@ module Rails
         end
 
         def controller_class_name
-          (controller_class_path + [controller_file_name]).map!{ |m| m.camelize }.join('::')
+          (controller_class_path + [controller_file_name]).map!(&:camelize).join('::')
         end
 
         def controller_i18n_scope
diff --git a/railties/lib/rails/info.rb b/railties/lib/rails/info.rb
index 94ede76932..5909446b66 100644
--- a/railties/lib/rails/info.rb
+++ b/railties/lib/rails/info.rb
@@ -8,7 +8,7 @@ module Rails
     mattr_accessor :properties
     class << (@@properties = [])
       def names
-        map {|val| val.first }
+        map(&:first)
       end
 
       def value_for(property_name)
@@ -26,7 +26,7 @@ module Rails
       end
 
       def to_s
-        column_width = properties.names.map {|name| name.length}.max
+        column_width = properties.names.map(&:length).max
         info = properties.map do |name, value|
           value = value.join(", ") if value.is_a?(Array)
           "%-#{column_width}s   %s" % [name, value]
diff --git a/railties/lib/rails/paths.rb b/railties/lib/rails/paths.rb
index d11804af17..5458036219 100644
--- a/railties/lib/rails/paths.rb
+++ b/railties/lib/rails/paths.rb
@@ -77,23 +77,23 @@ module Rails
       end
 
       def all_paths
-        values.tap { |v| v.uniq! }
+        values.tap(&:uniq!)
       end
 
       def autoload_once
-        filter_by { |p| p.autoload_once? }
+        filter_by(&:autoload_once?)
       end
 
       def eager_load
-        filter_by { |p| p.eager_load? }
+        filter_by(&:eager_load?)
       end
 
       def autoload_paths
-        filter_by { |p| p.autoload? }
+        filter_by(&:autoload?)
       end
 
       def load_paths
-        filter_by { |p| p.load_path? }
+        filter_by(&:load_path?)
       end
 
     private
diff --git a/railties/test/railties/engine_test.rb b/railties/test/railties/engine_test.rb
index 6239af2066..260ee0eda9 100644
--- a/railties/test/railties/engine_test.rb
+++ b/railties/test/railties/engine_test.rb
@@ -518,7 +518,7 @@ YAML
 
       def call(env)
         response = @app.call(env)
-        response[2].each { |b| b.upcase! }
+        response[2].each(&:upcase!)
         response
       end
     end