staticmethod tests fail when declared in a superclass

[radzak]

staticmethod test fails if you declare it in a superclass:

@pytest.fixture
def fixture():
    return True

class TestFoo:
    @staticmethod
    def test_me(fixture):
        assert fixture

class TestBar(TestFoo):
    ...

TestBar.test_me fails due to the TypeError: test_me() missing 1 required positional argument: 'fixture'.

TestFoo.test_me passes correctly.

[pytestbot]

GitMate.io thinks possibly related issues are #747 (flakes test fail), #2528 (staticmethod functions are not collected for testing), #701 (py.test.exe - failed to create process), #2699 (staticmethod tests don't work with fixtures), and #1845 (Some tests fail on FreeBSD).

[Drew-Ack]

It would be really nice to see what you are trying to accomplish in your TestBar class.

I was able to implement working code this way.

conftest.py

All fixtures go here.

import pytest
@pytest.fixture
def fixture():
    return True

test_static.py

class TestFoo(object):                                         
    @staticmethod                                              
    def test_me(fixture):                                      
        print("running TestFoo's test_me")                     
        assert fixture                                         
                                                               
class TestBar(TestFoo):                                                                                         
    def test_me_through_TestFoo(self, fixture):                
        TestFoo.test_me(fixture)                                                              
    def test_me_trough_TestBar(self, fixture):                 
        TestBar.test_me(fixture)                               

Results

TestFoo.test_me .
TestBar.test_me F
TestBar.test_me_through_TestFoo .
TestBar.test_me_through_TestBar .

It seems to be an inheritance issue.
When TestBar inherits TestFoo's methods, it fires off the test_me. I assume it has an issue with the signature. Ill need someone with more experience to chime in with why this is.

A possible fix

Change it from a static method to a class method.

class TestFoo(object):                           
    @classmethod                                 
    def test_me(cls, fixture):                   
        print("running TestFoo's test_me")       
        assert fixture        

TestFoo wont be able to run test_me as a test itself, but classes that inherit from TestFoo will run properly.

Results

TestFoo.test_me_through_TestFoo    .
TestFoo.test_me_through_TestBard   .

Some Resources

A little light reading on class method and static methods among a few other things.

[nicoddemus]

Thanks @Drew-Ack for providing a working solution! @radzak is the solution good enough as a workaround?

[nicoddemus]

After all the recent trouble we got from wrapping test functions to issue warnings when they get called directly (#3661, #3781), I wonder if it is wise for us to support this at all.

What do you think @RonnyPfannschmidt?