Warn when no specs are used

[RonnyPfannschmidt]

Mock without specs is so forgiving that people often write tests whose asserts do nothing

This is mainly because the apu of mock is severely flawed and error-prone

[The-Compiler]

I agree, but I don't think it's the job of pytest-mock to fix this up.

I plan to write a pylint plugin for this some day, to statically check mocks are always used with spec or autospec.

I wonder, is there a better mocking library (i.e. with a more sane API) which could be exposed to pytest?

[RonnyPfannschmidt]

There is none, generally mocking is tricky and a sign of bad structure

I wouldn't want to invent one

[nicoddemus]

Hi @RonnyPfannschmidt,

What do you suggest exactly? If one uses mocker.patch without passing autospec=True or a spec, to issue a pytest-warning?

[RonnyPfannschmidt]

Yes

[nicoddemus]

Fair enough. :smile:

I don't want current users to suddenly start to receive warnings for valid uses of the API though, so I'm thinking of making this an ini option:

[pytest]
mock_warnings = yes  # defaults to no

@RonnyPfannschmidt, @The-Compiler, what do you guys think?

[RonnyPfannschmidt]

:+1:

[chishaku]

Thankful I found this issue.

I'm new to mocking and I was wondering why the test wasn't failing when a mock was called more than once.

I had

mocked_function = mocker.patch('app.function')
do_something()
mocked_function.called_once()

The test passed even though called_once isn't even a function.

After I added autospec=True based on the contents of this issue, I am seeing the errors I'm expecting.

+1 for the mock_warnings config option.

Even an update to the docs would be very helpful