Multiple parametrization of a fixture?

[sadra-barikbin]

Is there a way to parametrize a fixture like we do by stacking pytest.mark.parametrizes on a test function?

[portyu9]

Hi @sadra-barikbin

You don't stack multiple @pytest.fixture(params=...) decorators in the same way that you can stack @pytest.mark.parametrize.

If you want a Cartesian product, one clean approach is to make the parameters separate fixtures:

@pytest.fixture(params=[1, 2])
def number(request):
    return request.param


@pytest.fixture(params=["a", "b"])
def letter(request):
    return request.param


@pytest.fixture
def combined(number, letter):
    return number, letter

Any test using combined will run with:

(1, "a")
(1, "b")
(2, "a")
(2, "b")

Alternatively, if the pair conceptually belongs to one fixture:

import itertools
import pytest

@pytest.fixture(params=list(itertools.product([1, 2], ["a", "b"])))
def combined(request):
    return request.param

Both produce the Cartesian-product behavior; the first form is usually nicer when the individual parameters are useful as fixtures themselves.

Please mark this answer as accepted if it helped, thank you.