Pytest overriding default value of a parameter for a fixture

I have the following simple code:

import pytest

@pytest.fixture
def func_multiply(a,b,c=0):
    return a*b*c

@pytest.mark.parametrize(
    "a,b,c",
    [
        (5,1,5),
    ]
)
def test_bug(func_multiply):
    assert func_multiply == 25

I expect the test to pass but for some reason the value for c isn't getting passed into the fixture. The idea is that if another function used the same fixture without passing in a value for c, the default value of 0 would be used. In this case though, where value of c is specified, the default should be overridden.

It seems that the problem lies in the implementation of the test_bug function. Specifically, it looks like you're not actually calling the func_multiply fixture with the parameters from the @pytest.mark.parametrize decorator.

To address this issue, you can modify the test_bug function to include the a, b, and c parameters and pass them to func_multiply like this:

def test_bug(func_multiply, a, b, c):
    assert func_multiply(a, b, c) == 25

By doing this, you'll be able to test the behavior of the fixture with the parameters specified in @pytest.mark.parametrize.

Also, be sure to add the a, b, and c parameters to the @pytest.mark.parametrize decorator, like this:

@pytest.mark.parametrize(
    "a,b,c",
    [
        (5,1,5),
    ]
)

This will ensure that the values for a, b, and c are correctly passed into the test_bug function.

Here's the final code:

import pytest

@pytest.fixture
def func_multiply():
    def _func_multiply(a, b, c=0):
        return a*b*c
    return _func_multiply

@pytest.mark.parametrize(
    "a,b,c",
    [
        (5,1,5),
    ]
)
def test_bug(func_multiply, a, b, c):
    assert func_multiply(a, b, c) == 25

With these changes, the test should now pass and the fixture should behave as expected.