diff --git a/actionpack/test/abstract/translation_test.rb b/actionpack/test/abstract/translation_test.rb
index 8ec50fd57a2a4869487e87bf88fc075b90ce11ac..0194ee943fe57826e84802cb297b4cc070e928d0 100644
--- a/actionpack/test/abstract/translation_test.rb
+++ b/actionpack/test/abstract/translation_test.rb
@@ -3,7 +3,7 @@
 # class TranslatingController < ActionController::Base
 # end
 
-class TranslationControllerTest < Test::Unit::TestCase
+class TranslationControllerTest < ActiveSupport::TestCase
   def setup
     @controller = ActionController::Base.new
   end
@@ -23,4 +23,4 @@ def test_action_controller_base_responds_to_localize
   def test_action_controller_base_responds_to_l
     assert_respond_to @controller, :l
   end
-end
\ No newline at end of file
+end
diff --git a/actionpack/test/controller/base_test.rb b/actionpack/test/controller/base_test.rb
index a4f858d06d80cd6d0199f2400e10a25ef9c83de4..c5c48bc559b1f2ef0ff997e0d8c1d46b92fe2a65 100644
--- a/actionpack/test/controller/base_test.rb
+++ b/actionpack/test/controller/base_test.rb
@@ -106,7 +106,7 @@ def test_record_identifier
   end
 end
 
-class ControllerInstanceTests < Test::Unit::TestCase
+class ControllerInstanceTests < ActiveSupport::TestCase
   def setup
     @empty = EmptyController.new
     @contained = Submodule::ContainedEmptyController.new
diff --git a/actionpack/test/controller/integration_test.rb b/actionpack/test/controller/integration_test.rb
index 2ad95f5c296042251ae35e1a0824356b504bc5be..a328372cffe069e87243855d188866b28e03bfae 100644
--- a/actionpack/test/controller/integration_test.rb
+++ b/actionpack/test/controller/integration_test.rb
@@ -2,7 +2,7 @@
 require 'controller/fake_controllers'
 require 'action_controller/vendor/html-scanner'
 
-class SessionTest < Test::Unit::TestCase
+class SessionTest < ActiveSupport::TestCase
   StubApp = lambda { |env|
     [200, {"Content-Type" => "text/html", "Content-Length" => "13"}, ["Hello, World!"]]
   }
@@ -165,7 +165,7 @@ def test_xml_http_request_override_accept
   end
 end
 
-class IntegrationTestTest < Test::Unit::TestCase
+class IntegrationTestTest < ActiveSupport::TestCase
   def setup
     @test = ::ActionDispatch::IntegrationTest.new(:app)
     @test.class.stubs(:fixture_table_names).returns([])
diff --git a/actionpack/test/controller/record_identifier_test.rb b/actionpack/test/controller/record_identifier_test.rb
index f3e5ff8a47aec2be317b98065cbd468b674ed9c9..eb38b81e85f82975826370e2011eb05039febe91 100644
--- a/actionpack/test/controller/record_identifier_test.rb
+++ b/actionpack/test/controller/record_identifier_test.rb
@@ -1,7 +1,7 @@
 require 'abstract_unit'
 require 'controller/fake_models'
 
-class RecordIdentifierTest < Test::Unit::TestCase
+class RecordIdentifierTest < ActiveSupport::TestCase
   include ActionController::RecordIdentifier
 
   def setup
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index c9785d9b8a22bd66e8a027c012c2b084db5e967e..bf33b8cdd79d0e41eae3b0a43d0412b86d66d84d 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -12,7 +12,7 @@ def rescue_action(e) raise e end
 ROUTING = ActionDispatch::Routing
 
 # See RFC 3986, section 3.3 for allowed path characters.
-class UriReservedCharactersRoutingTest < Test::Unit::TestCase
+class UriReservedCharactersRoutingTest < ActiveSupport::TestCase
   include RoutingTestHelpers
 
   def setup
@@ -72,7 +72,7 @@ def url_for(options)
   end
 end
 
-class LegacyRouteSetTests < Test::Unit::TestCase
+class LegacyRouteSetTests < ActiveSupport::TestCase
   include RoutingTestHelpers
 
   attr_reader :rs
diff --git a/actionpack/test/controller/runner_test.rb b/actionpack/test/controller/runner_test.rb
index 24c220dcd57d871063dc098f149979a46d83b03b..3e9383abb2b2307027f6d27679cfd5459e4c8439 100644
--- a/actionpack/test/controller/runner_test.rb
+++ b/actionpack/test/controller/runner_test.rb
@@ -2,7 +2,7 @@
 require 'action_dispatch/testing/integration'
 
 module ActionDispatch
-  class RunnerTest < Test::Unit::TestCase
+  class RunnerTest < ActiveSupport::TestCase
     class MyRunner
       include Integration::Runner
 
diff --git a/actionpack/test/controller/selector_test.rb b/actionpack/test/controller/selector_test.rb
index 8ce9e43402a1c54cbaaea0edb63b927a879470b5..5e302da212473fcba3f62437ba8b2abfaab37935 100644
--- a/actionpack/test/controller/selector_test.rb
+++ b/actionpack/test/controller/selector_test.rb
@@ -7,7 +7,7 @@
 require 'controller/fake_controllers'
 require 'action_controller/vendor/html-scanner'
 
-class SelectorTest < Test::Unit::TestCase
+class SelectorTest < ActiveSupport::TestCase
   #
   # Basic selector: element, id, class, attributes.
   #
diff --git a/actionpack/test/dispatch/reloader_test.rb b/actionpack/test/dispatch/reloader_test.rb
index 3411bd14ea24f7ff40fbd8be120ac09953cf5591..e371c3b0c120ba383188ae419229b8f6d0773c22 100644
--- a/actionpack/test/dispatch/reloader_test.rb
+++ b/actionpack/test/dispatch/reloader_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class ReloaderTest < Test::Unit::TestCase
+class ReloaderTest < ActiveSupport::TestCase
   Reloader = ActionDispatch::Reloader
 
   def test_prepare_callbacks
diff --git a/actionpack/test/template/compiled_templates_test.rb b/actionpack/test/template/compiled_templates_test.rb
index 30d798d693278f9e519f13c129e842d673540dab..f5dc2fbb3394eb5c7249b8e3ac2b6a6174b58ec6 100644
--- a/actionpack/test/template/compiled_templates_test.rb
+++ b/actionpack/test/template/compiled_templates_test.rb
@@ -1,7 +1,7 @@
 require 'abstract_unit'
 require 'controller/fake_models'
 
-class CompiledTemplatesTest < Test::Unit::TestCase
+class CompiledTemplatesTest < ActiveSupport::TestCase
   def setup
     # Clean up any details key cached to expose failures
     # that otherwise would appear just on isolated tests
diff --git a/actionpack/test/template/date_helper_i18n_test.rb b/actionpack/test/template/date_helper_i18n_test.rb
index d45215acfde53fcd9db2b08654ba72a6faa8af59..e3d3d5ff770e65de3285cd8b0fb307afd91426d5 100644
--- a/actionpack/test/template/date_helper_i18n_test.rb
+++ b/actionpack/test/template/date_helper_i18n_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class DateHelperDistanceOfTimeInWordsI18nTests < Test::Unit::TestCase
+class DateHelperDistanceOfTimeInWordsI18nTests < ActiveSupport::TestCase
   include ActionView::Helpers::DateHelper
   attr_reader :request
 
@@ -71,7 +71,7 @@ def test_distance_of_time_pluralizations
   end
 end
 
-class DateHelperSelectTagsI18nTests < Test::Unit::TestCase
+class DateHelperSelectTagsI18nTests < ActiveSupport::TestCase
   include ActionView::Helpers::DateHelper
   attr_reader :request
 
diff --git a/actionpack/test/template/erb_util_test.rb b/actionpack/test/template/erb_util_test.rb
index 790ab1c74c202df317507f29bb8e38b2e0bb1073..eba2ef64e0aae0e105e596d1ccb6b398192747c7 100644
--- a/actionpack/test/template/erb_util_test.rb
+++ b/actionpack/test/template/erb_util_test.rb
@@ -1,7 +1,7 @@
 require 'abstract_unit'
 require 'active_support/core_ext/object/inclusion'
 
-class ErbUtilTest < Test::Unit::TestCase
+class ErbUtilTest < ActiveSupport::TestCase
   include ERB::Util
 
   ERB::Util::HTML_ESCAPE.each do |given, expected|
diff --git a/actionpack/test/template/html-scanner/cdata_node_test.rb b/actionpack/test/template/html-scanner/cdata_node_test.rb
index 1822cc565abb0ffb54c1f8e44a1ff1119fcd3129..9b581746419ae81068f62d01f20adf2e132e91c6 100644
--- a/actionpack/test/template/html-scanner/cdata_node_test.rb
+++ b/actionpack/test/template/html-scanner/cdata_node_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class CDATANodeTest < Test::Unit::TestCase
+class CDATANodeTest < ActiveSupport::TestCase
   def setup
     @node = HTML::CDATA.new(nil, 0, 0, "<p>howdy</p>")
   end
diff --git a/actionpack/test/template/html-scanner/document_test.rb b/actionpack/test/template/html-scanner/document_test.rb
index 3db2fba7839e5ab7a9707244fd7302faa664b4ec..17f045d549b157fa19bc7190134b72076f1a61d0 100644
--- a/actionpack/test/template/html-scanner/document_test.rb
+++ b/actionpack/test/template/html-scanner/document_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class DocumentTest < Test::Unit::TestCase
+class DocumentTest < ActiveSupport::TestCase
   def test_handle_doctype
     doc = nil
     assert_nothing_raised do
diff --git a/actionpack/test/template/html-scanner/node_test.rb b/actionpack/test/template/html-scanner/node_test.rb
index f4b9b198e8cbe7f5baa5274bcb89f780bcf14d2e..5b5d09203697730a24ff413f3d72b4e86c9e3bbb 100644
--- a/actionpack/test/template/html-scanner/node_test.rb
+++ b/actionpack/test/template/html-scanner/node_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class NodeTest < Test::Unit::TestCase
+class NodeTest < ActiveSupport::TestCase
 
   class MockNode
     def initialize(matched, value)
diff --git a/actionpack/test/template/html-scanner/tag_node_test.rb b/actionpack/test/template/html-scanner/tag_node_test.rb
index 3b72243e7d81becedc7b6384014e0ec62edc2951..a29d2d43d772d73af11290eeaf7426087f0e7c34 100644
--- a/actionpack/test/template/html-scanner/tag_node_test.rb
+++ b/actionpack/test/template/html-scanner/tag_node_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class TagNodeTest < Test::Unit::TestCase
+class TagNodeTest < ActiveSupport::TestCase
   def test_open_without_attributes
     node = tag("<tag>")
     assert_equal "tag", node.name
diff --git a/actionpack/test/template/html-scanner/text_node_test.rb b/actionpack/test/template/html-scanner/text_node_test.rb
index 6f61253ffa3c27014835976e467bcce29dec5e7f..cbcb9e78f0a37e035a487566be248818c0c73f67 100644
--- a/actionpack/test/template/html-scanner/text_node_test.rb
+++ b/actionpack/test/template/html-scanner/text_node_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class TextNodeTest < Test::Unit::TestCase
+class TextNodeTest < ActiveSupport::TestCase
   def setup
     @node = HTML::Text.new(nil, 0, 0, "hello, howdy, aloha, annyeong")
   end
diff --git a/actionpack/test/template/html-scanner/tokenizer_test.rb b/actionpack/test/template/html-scanner/tokenizer_test.rb
index bf45a7c2e3a7b917aee52396a57daa212bb8d670..1d59de23b645d921ddff05ec3212a86383d4ba3b 100644
--- a/actionpack/test/template/html-scanner/tokenizer_test.rb
+++ b/actionpack/test/template/html-scanner/tokenizer_test.rb
@@ -1,6 +1,6 @@
 require 'abstract_unit'
 
-class TokenizerTest < Test::Unit::TestCase
+class TokenizerTest < ActiveSupport::TestCase
 
   def test_blank
     tokenize ""
diff --git a/actionpack/test/ts_isolated.rb b/actionpack/test/ts_isolated.rb
index 5670d93613ef029a652bec690e1b543947a6d66b..0670e0100bc5c00fa0402c4ffc00f28ed60abcca 100644
--- a/actionpack/test/ts_isolated.rb
+++ b/actionpack/test/ts_isolated.rb
@@ -3,8 +3,9 @@
 require 'test/unit'
 require 'rbconfig'
 require 'active_support/core_ext/kernel/reporting'
+require 'abstract_unit'
 
-class TestIsolated < Test::Unit::TestCase
+class TestIsolated < ActiveSupport::TestCase
   ruby = File.join(*RbConfig::CONFIG.values_at('bindir', 'RUBY_INSTALL_NAME'))
 
   Dir["#{File.dirname(__FILE__)}/{abstract,controller,dispatch,template}/**/*_test.rb"].each do |file|