Test keyword args in requests for Rails 5; fallback for earlier versions

kwargs: params,session,flash,method,body

Fix Rails 5 DEPRECATION WARNING

test/support/rails5_shims.rb

@@ -0,0 +1,29 @@
+module Rails5Shims
+  module ControllerTests
+    # https://github.com/rails/rails/blob/b217354/actionpack/lib/action_controller/test_case.rb
+    REQUEST_KWARGS = [:params, :session, :flash, :method, :body, :xhr]
+
+    # Fold kwargs from test request into args
+    # Band-aid for DEPRECATION WARNING
+    def get(path, *args)
+      hash = args && args[0]
+      if hash.respond_to?(:key)
+        Rails5Shims::ControllerTests::REQUEST_KWARGS.each do |kwarg|
+          next unless hash.key?(kwarg)
+          hash.merge! hash.delete(kwarg)
+        end
+      end
+      super
+    end
+
+    # Uncomment for debugging where the kwargs warnings come from
+    # def non_kwarg_request_warning
+    #   super.tap do
+    #     STDOUT.puts caller[2..3]
+    #   end
+    # end
+  end
+end
+if Rails::VERSION::MAJOR < 5
+  ActionController::TestCase.send :include, Rails5Shims::ControllerTests
+end