Inherit from MiniTest::Unit::TestCase instead of MiniTest::Spec

actionmailer/lib/action_mailer/test_case.rb

@@ -10,13 +10,6 @@ def initialize(name)
   end
 
   class TestCase < ActiveSupport::TestCase
-
-    # Use AM::TestCase for the base class when describing a mailer
-    register_spec_type(self) do |desc|
-      Class === desc && desc < ActionMailer::Base
-    end
-    register_spec_type(/Mailer( ?Test)?\z/i, self)
-
     module Behavior
       extend ActiveSupport::Concern
 

actionpack/lib/action_controller/test_case.rb

@@ -360,13 +360,6 @@ def exists?
   #
   #  assert_redirected_to page_url(title: 'foo')
   class TestCase < ActiveSupport::TestCase
-
-    # Use AC::TestCase for the base class when describing a controller
-    register_spec_type(self) do |desc|
-      Class === desc && desc < ActionController::Metal
-    end
-    register_spec_type(/Controller( ?Test)?\z/i, self)
-
     module Behavior
       extend ActiveSupport::Concern
       include ActionDispatch::TestProcess

actionpack/lib/action_dispatch/testing/integration.rb

@@ -491,9 +491,6 @@ class IntegrationTest < ActiveSupport::TestCase
     include ActionController::TemplateAssertions
     include ActionDispatch::Routing::UrlFor
 
-    # Use AD::IntegrationTest for acceptance tests
-    register_spec_type(/(Acceptance|Integration) ?Test\z/i, self)
-
     @@app = nil
 
     def self.app

actionpack/lib/action_view/test_case.rb

@@ -30,9 +30,6 @@ def initialize
       end
     end
 
-    # Use AV::TestCase for the base class for helpers and views
-    register_spec_type(/(Helper|View)( ?Test)?\z/i, self)
-
     module Behavior
       extend ActiveSupport::Concern
 

activesupport/lib/active_support/test_case.rb

@@ -1,5 +1,5 @@
 gem 'minitest' # make sure we get the gem, not stdlib
-require 'minitest/spec'
+require 'minitest/unit'
 require 'active_support/testing/tagged_logging'
 require 'active_support/testing/setup_and_teardown'
 require 'active_support/testing/assertions'
@@ -17,13 +17,7 @@
 end
 
 module ActiveSupport
-  class TestCase < ::MiniTest::Spec
-
-    # Use AS::TestCase for the base class when describing a model
-    register_spec_type(self) do |desc|
-      Class === desc && desc < ActiveRecord::Base
-    end
-
+  class TestCase < ::MiniTest::Unit::TestCase
     Assertion = MiniTest::Assertion
     alias_method :method_name, :__name__
 

railties/test/engine_test.rb

@@ -1,7 +1,7 @@
 require 'abstract_unit'
 
 class EngineTest < ActiveSupport::TestCase
-  it "reports routes as available only if they're actually present" do
+  test "reports routes as available only if they're actually present" do
     engine = Class.new(Rails::Engine) do
       def initialize(*args)
         @routes = nil