Patching a coroutine fails if it's imported directly in module being tested

[rduldulao]

We were exploring aio_pika and we had this test:

class OurTest(TestCase):
    async def test_one(self):
         with asynctest.mock.patch('aio_pika.robust_connect') as mcr:
             await AdapterClass.create(**options)  #options is a dict declared prior to test class
             mcr.assert_called_once_with(**options)

The code under test is like:

from aio_pika import connect_robust
class OurClass(object):
    def _init__(self, host, port, user, pass):
       self.host = host
       #etc..
       self.connection = None
   
    @classmethod
    async def create(cls, host, port, user, pass):
        _instance = cls(host, port, user, pass)
        self.connection = await connect_robust(host=host, port=port, ...etc...)

As it is, the assertion will fail. But if we modify the class under test import to

import aio_pika

and modify the call further to

self.connection = await aio_pika.connect_robust(.....)

....test will succeed.

[Wesmania]

I think this is expected behaviour in line with unittest.mock, as in: http://www.voidspace.org.uk/python/mock/patch.html#id1