python - Django Rest Framework: How can I patch a serializer for unit testing, when it's used in the serializer_class attribute? -

i have serializer create() function. when post request, want function called , create new object. when in browser, works , calls function. inside test, says function not called. think have done wrong patch, because in api set serializer_class , class called somewhere inside framework. thought was, not need test this, because should guaranteed rest_framework, if way, framework should call function correct parameters.

# serializers.py class fooserializer(models.modelserializer):     class meta:         ...      def create(self, validated_data):         ...  # apis.py class fooapi(generics.createapiview):     serializer_class = fooserializer  # tests.py @patch('apis.fooserializer'): def test_that_create_is_called(self, mock):     mock.create = magicmock()     mock.create.return_value = foo() # foo model     response = self.client.post('/foo', {name: 'test'})     self.asserttrue(mock.create.called) # => output says "false not true" 

your current code mocking entire serializer object, overkill , stop create method ever being called if it's expected called internal logic on serializer.

instead want patch single method - this:

@patch('apis.fooserializer', 'create') 

now test method receives magicmock object instance has replaced create method.

so test method becomes:

def test_that_create_is_called(self, mock_method):     response = self.client.post('/foo', {name: 'test'})     self.asserttrue(mock_method.called)