Patching(mocking) forms form in django tests

Question

I tried to mock form with mock.patch and can`t. I have this code

forms.py

class CreatePostForm(object):
    pass

views.py:

from forms import CreatePostForm

def doit():
    print CreatePostForm()

and I want to to test this view in isolation. I tried to patch form with mock.patch and i wrote something like that:

tests.py:

from mock import patch

import views

with patch('forms.CreatePostForm') as Form:
    views.doit()

I tried to google for solution and find nothing

Answered: thanks @dstanek for good answer and good sample of code

Answer 1

When you use patch you specify the target of the object you want to mock. This is usually the place where it is imported, not where it is defined.

This is because by the time your test runs the views module has already been imported. If you are importing the class like I'm doing in my example below then the views module will contain a reference to the forms.CreatePostForm. So changing forms.CreatePostForm would not change this reference. Things would be different if you imported the module as specified forms.CreatePostForm in your view.

I've included an extremely minimal example below.

forms.py

class CreatePostForm(object):
    pass

views.py:

from forms import CreatePostForm

def doit():
    print CreatePostForm()

tests.py:

from mock import patch

import views

with patch('views.CreatePostForm') as Form:
    views.doit()