How to create two arguments in "pytest_generate_tests(metafunc)"

[zhangmingyuu]

Hi, dear developers:
Can I specify two custom parameters in this method like below:

def pytest_generate_tests(metafunc):
    if "test_scope" in metafunc.fixturenames:
            if demo = 1:
                metafunc.parametrize("test_scope", [scope]) 
                metafunc.parametrize("second_scope", [scope2])

The problem I encountered first is: when I receive custom parameters, I need to create two different parameters at the same time,

I don't know if my problem is described clearly enough, if there is something unclear, please let me know
Thank you

[luigiscofano]

Yes. If the two values belong together, pass both parameter names to a single metafunc.parametrize() call and provide a tuple for each test case:

# test_example.py

def pytest_generate_tests(metafunc):
    if {"test_scope", "second_scope"}.issubset(
        metafunc.fixturenames
    ):
        metafunc.parametrize(
            "test_scope,second_scope",
            [("first", 1), ("second", 2)],
        )


def test_pair(test_scope, second_scope):
    assert {"first": 1, "second": 2}[test_scope] == second_scope

This produces two cases: ("first", 1) and ("second", 2).

For your existing variables, the parametrization would be:

metafunc.parametrize(
    "test_scope,second_scope",
    [(scope, scope2)],
)

Your original approach with two separate calls is also valid when both parameters are requested. With multiple values in each call, however, it generates every combination rather than matching values as pairs.

Also, if the condition in your example is literal Python, use if demo == 1:; if demo = 1: is invalid syntax.

The paired example was verified with pytest 9.2.0: 2 passed.

Reference: pytest parametrization documentation.