      def test_modelform_validation_failure_raises_response_exception(self):
          self.validation_failure_raises_response_exception(self.MockModelFormValidator())
  
      def test_modelform_validation_does_not_allow_extra_fields_by_default(self):
          self.validation_does_not_allow_extra_fields_by_default(self.MockModelFormValidator())
  
      def test_modelform_validation_allows_extra_fields_if_explicitly_set(self):
          self.validation_allows_extra_fields_if_explicitly_set(self.MockModelFormValidator())
  
      def test_modelform_validation_does_not_require_extra_fields_if_explicitly_set(self):
 
</s> remove         self.validation_failure_raises_response_exception(self.MockModelFormValidator())
 </s> add         validator = ModelFormValidator(self.MockModelFormView())
        self.validation_failure_raises_response_exception(validator) </s> remove         self.validation_allows_extra_fields_if_explicitly_set(self.MockModelFormValidator())
 </s> add         validator = ModelFormValidator(self.MockModelFormView())
        self.validation_allows_extra_fields_if_explicitly_set(validator) </s> remove         self.validation_does_not_require_extra_fields_if_explicitly_set(self.MockModelFormValidator())
 </s> add         validator = ModelFormValidator(self.MockModelFormView())
        self.validation_does_not_require_extra_fields_if_explicitly_set(validator) </s> remove         self.validation_returns_content_unchanged_if_already_valid_and_clean(self.MockModelFormValidator())
 </s> add         validator = ModelFormValidator(self.MockModelFormView())
        self.validation_returns_content_unchanged_if_already_valid_and_clean(validator) </s> remove         self.validation_failed_due_to_no_content_returns_appropriate_message(self.MockModelFormValidator())
 </s> add         validator = ModelFormValidator(self.MockModelFormView())
        self.validation_failed_due_to_no_content_returns_appropriate_message(validator)
        validator = ModelFormValidator(self.MockModelFormView())
        self.validation_does_not_allow_extra_fields_by_default(validator)
      def test_modelform_validation_failure_raises_response_exception(self):
          self.validation_failure_raises_response_exception(self.MockModelFormValidator())
  
      def test_modelform_validation_does_not_allow_extra_fields_by_default(self):
        validator = ModelFormValidator(self.MockModelFormView())
        self.validation_does_not_allow_extra_fields_by_default(validator)
  
      def test_modelform_validation_allows_extra_fields_if_explicitly_set(self):
          self.validation_allows_extra_fields_if_explicitly_set(self.MockModelFormValidator())
  
      def test_modelform_validation_does_not_require_extra_fields_if_explicitly_set(self):
keep keep keep keep replace keep keep keep keep keep
 Lots of validator tests passing after refactor 
djangorestframework/tests/validators.py