Merge pull request #40125 from jhawthorn/actionview_test_case_isolation

Use a unique controller class per ActionView::TestCase

actionpack/lib/action_controller/metal.rb

@@ -126,7 +126,7 @@ class Metal < AbstractController::Base
     # ==== Returns
     # * <tt>string</tt>
     def self.controller_name
-      @controller_name ||= name.demodulize.delete_suffix("Controller").underscore
+      @controller_name ||= (name.demodulize.delete_suffix("Controller").underscore unless anonymous?)
     end
 
     def self.make_response!(request)

actionview/lib/action_view/test_case.rb

@@ -16,11 +16,12 @@ class TestController < ActionController::Base
       attr_accessor :request, :response, :params
 
       class << self
-        attr_writer :controller_path
+        # Overrides AbstractController::Base#controller_path
+        attr_accessor :controller_path
       end
 
       def controller_path=(path)
-        self.class.controller_path = (path)
+        self.class.controller_path = path
       end
 
       def initialize
@@ -101,7 +102,8 @@ def include_helper_modules!
       end
 
       def setup_with_controller
-        @controller = ActionView::TestCase::TestController.new
+        controller_class = Class.new(ActionView::TestCase::TestController)
+        @controller = controller_class.new
         @request = @controller.request
         @view_flow = ActionView::OutputFlow.new
         # empty string ensures buffer has UTF-8 encoding as
@@ -109,8 +111,8 @@ def setup_with_controller
         @output_buffer = ActiveSupport::SafeBuffer.new ""
         @rendered = +""
 
-        make_test_case_available_to_view!
-        say_no_to_protect_against_forgery!
+        test_case_instance = self
+        controller_class.define_method(:_test_case) { test_case_instance }
       end
 
       def config
@@ -160,33 +162,24 @@ def view_rendered?(view, expected_locals)
       included do
         setup :setup_with_controller
         ActiveSupport.run_load_hooks(:action_view_test_case, self)
-      end
 
-    private
-      # Need to experiment if this priority is the best one: rendered => output_buffer
-      def document_root_element
-        Nokogiri::HTML::Document.parse(@rendered.blank? ? @output_buffer : @rendered).root
-      end
-
-      def say_no_to_protect_against_forgery!
-        _helpers.module_eval do
-          silence_redefinition_of_method :protect_against_forgery?
+        helper do
           def protect_against_forgery?
             false
           end
-        end
-      end
 
-      def make_test_case_available_to_view!
-        test_case_instance = self
-        _helpers.module_eval do
-          unless private_method_defined?(:_test_case)
-            define_method(:_test_case) { test_case_instance }
-            private :_test_case
+          def _test_case
+            controller._test_case
           end
         end
       end
 
+    private
+      # Need to experiment if this priority is the best one: rendered => output_buffer
+      def document_root_element
+        Nokogiri::HTML::Document.parse(@rendered.blank? ? @output_buffer : @rendered).root
+      end
+
       module Locals
         attr_accessor :rendered_views
 

actionview/test/template/test_case_test.rb

@@ -156,6 +156,13 @@ def render_from_helper
 
       assert_equal "controller_helper_method", some_method
     end
+
+    class AnotherTestClass < ActionView::TestCase
+      test "doesn't use controller helpers from other tests" do
+        assert_not_respond_to view, :render_from_helper
+        assert_not_includes @controller._helpers.instance_methods, :render_from_helper
+      end
+    end
   end
 
   class ViewAssignsTest < ActionView::TestCase