diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 0498b9d138f20..5f50bf5de6f27 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -358,7 +358,7 @@ class TestCase < ActiveSupport::TestCase
 
     # Use AS::TestCase for the base class when describing a model
     register_spec_type(self) do |desc|
-      desc < ActionController::Base
+      Class === desc && desc < ActionController::Base
     end
 
     module Behavior
diff --git a/actionpack/test/controller/new_base/render_action_test.rb b/actionpack/test/controller/new_base/render_action_test.rb
index aa44e0b2820a3..475bf9d3c92cb 100644
--- a/actionpack/test/controller/new_base/render_action_test.rb
+++ b/actionpack/test/controller/new_base/render_action_test.rb
@@ -86,8 +86,6 @@ class RenderLayoutTest < Rack::TestCase
     def setup
     end
 
-    describe "Both <controller_path>.html.erb and application.html.erb are missing"
-
     test "rendering with layout => true" do
       assert_raise(ArgumentError) do
         get "/render_action/basic/hello_world_with_layout", {}, "action_dispatch.show_exceptions" => false
@@ -154,8 +152,6 @@ def with_builder_and_layout
   end
 
   class LayoutTest < Rack::TestCase
-    describe "Only application.html.erb is present and <controller_path>.html.erb is missing"
-
     test "rendering implicit application.html.erb as layout" do
       get "/render_action_with_application_layout/basic/hello_world"
 
@@ -232,8 +228,6 @@ def hello_world_with_custom_layout
   end
 
   class ControllerLayoutTest < Rack::TestCase
-    describe "Only <controller_path>.html.erb is present and application.html.erb is missing"
-
     test "render hello_world and implicitly use <controller_path>.html.erb as a layout." do
       get "/render_action_with_controller_layout/basic/hello_world"
 
@@ -290,8 +284,6 @@ def hello_world_with_layout_nil
   end
 
   class ControllerLayoutTest < Rack::TestCase
-    describe "Both <controller_path>.html.erb and application.html.erb are present"
-
     test "rendering implicitly use <controller_path>.html.erb over application.html.erb as a layout" do
       get "/render_action_with_both_layouts/basic/hello_world"
 
diff --git a/actionpack/test/controller/new_base/render_template_test.rb b/actionpack/test/controller/new_base/render_template_test.rb
index 00c7df2af8fc4..156d87c3212cd 100644
--- a/actionpack/test/controller/new_base/render_template_test.rb
+++ b/actionpack/test/controller/new_base/render_template_test.rb
@@ -160,8 +160,6 @@ def with_custom_layout
   end
 
   class TestWithLayout < Rack::TestCase
-    describe "Rendering with :template using implicit or explicit layout"
-
     test "rendering with implicit layout" do
       with_routing do |set|
         set.draw { get ':controller', :action => :index }
diff --git a/actionpack/test/controller/new_base/render_text_test.rb b/actionpack/test/controller/new_base/render_text_test.rb
index f8d02e8b6c22a..d6c3926a4d7a5 100644
--- a/actionpack/test/controller/new_base/render_text_test.rb
+++ b/actionpack/test/controller/new_base/render_text_test.rb
@@ -63,8 +63,6 @@ def with_ivar_in_layout
   end
 
   class RenderTextTest < Rack::TestCase
-    describe "Rendering text using render :text"
-
     test "rendering text from an action with default options renders the text with the layout" do
       with_routing do |set|
         set.draw { get ':controller', :action => 'index' }
diff --git a/activesupport/lib/active_support/test_case.rb b/activesupport/lib/active_support/test_case.rb
index e5e9aa8cc71e3..d2b8e602f940f 100644
--- a/activesupport/lib/active_support/test_case.rb
+++ b/activesupport/lib/active_support/test_case.rb
@@ -3,10 +3,10 @@
 require 'active_support/testing/setup_and_teardown'
 require 'active_support/testing/assertions'
 require 'active_support/testing/deprecation'
-require 'active_support/testing/declarative'
 require 'active_support/testing/isolation'
 require 'active_support/testing/mocha_module'
 require 'active_support/core_ext/kernel/reporting'
+require 'active_support/deprecation'
 
 module ActiveSupport
   class TestCase < ::MiniTest::Spec
@@ -15,7 +15,7 @@ class TestCase < ::MiniTest::Spec
 
     # Use AS::TestCase for the base class when describing a model
     register_spec_type(self) do |desc|
-      desc < ActiveRecord::Model
+      Class === desc && desc < ActiveRecord::Model
     end
 
     Assertion = MiniTest::Assertion
@@ -35,7 +35,20 @@ def self.test_order # :nodoc:
     include ActiveSupport::Testing::SetupAndTeardown
     include ActiveSupport::Testing::Assertions
     include ActiveSupport::Testing::Deprecation
-    extend ActiveSupport::Testing::Declarative
+
+    def self.describe(text)
+      if block_given?
+        super
+      else
+        ActiveSupport::Deprecation.warn("`describe` without a block is deprecated, please switch to: `def self.name; #{text.inspect}; end`\n")
+
+        class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
+          def self.name
+            "#{text}"
+          end
+        RUBY_EVAL
+      end
+    end
 
     class << self
       alias :test :it
diff --git a/activesupport/lib/active_support/testing/declarative.rb b/activesupport/lib/active_support/testing/declarative.rb
deleted file mode 100644
index db554a954251c..0000000000000
--- a/activesupport/lib/active_support/testing/declarative.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-module ActiveSupport
-  module Testing
-    module Declarative
-
-      def self.extended(klass) #:nodoc:
-        klass.class_eval do
-
-          unless method_defined?(:describe)
-            def self.describe(text)
-              class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
-                def self.name
-                  "#{text}"
-                end
-              RUBY_EVAL
-            end
-          end
-
-        end
-      end
-    end
-  end
-end