clean as PR review

Author: Laurent Cobos

lib/rspec/rails/fixture_file_upload_support.rb

@@ -2,39 +2,32 @@ module RSpec
   module Rails
     # @private
     module FixtureFileUploadSupport
-      extend ActiveSupport::Concern
-
-      included do
-        delegate :fixture_file_upload, :to => :rails_fixture_file_wrapper
-      end
-
-    private
-
-      def rails_fixture_file_wrapper
-        resolved_fixture_path = (fixture_path || RSpec.configuration.fixture_path || '')
-        RailsFixtureFileWrapper.fixture_path = File.join(resolved_fixture_path, '')
-        RailsFixtureFileWrapper.instance
+      def self.included(other)
+        if defined?(ActionDispatch::TestProcess)
+          other.include ActionDispatch::TestProcess
+        end
+        other.extend FixturePathAttribute
       end
 
-      class RailsFixtureFileWrapper
-        class << self
-          attr_reader :fixture_path
+      module FixturePathAttribute
+        def fixture_path
+          @fixture_path ||= calculate_path
+        end
 
-          # Get the instance of wrapper
-          def instance
-            @instance ||= new
+        def fixture_path=(value)
+          # Rails 3.0..3.1 are using ActionController::TestCase class to resolve fixture_path
+          # see https://apidock.com/rails/v3.0.0/ActionDispatch/TestProcess/fixture_file_upload
+          if ActionController::TestCase.respond_to?(:fixture_path)
+            ActionController::TestCase.fixture_path = value
           end
+          @fixture_path = value
+        end
 
-          def fixture_path=(value)
-            # Rails 3.0..3.1 are using ActionController::TestCase class to resolve fixture_path
-            # see https://apidock.com/rails/v3.0.0/ActionDispatch/TestProcess/fixture_file_upload
-            if ActionController::TestCase.respond_to?(:fixture_path)
-              ActionController::TestCase.fixture_path = value
-            end
-            @fixture_path = value
-          end
+      private
 
-          include ActionDispatch::TestProcess if defined?(ActionDispatch::TestProcess)
+        def calculate_fixture_path
+          resolved_fixture_path = (fixture_path || RSpec.configuration.fixture_path || '')
+          self.fixture_path = File.join(resolved_fixture_path, '')
         end
       end
     end