[Python] How to concatenate several parametrized fixtures into a new fixture in py.test?

If I have two parametrized fixtures, how can I create a single test function that is called first with the instances of one fixture and then with the instances of the other fixture?

I guess it would make sense to create a new fixture that somehow concatenates the two existing fixtures. This works well for "normal" fixtures, but I don't seem to get it to work with parametrized fixtures.

Here is a simplified example of what I tried:

import pytest

@pytest.fixture(params=[1, 2, 3])
def lower(request):
return "i" * request.param

@pytest.fixture(params=[1, 2])
def upper(request):
return "I" * request.param

@pytest.fixture(params=['lower', 'upper'])
def all(request):
return request.getfuncargvalue(request.param)

def test_all(all):
assert 0, all


When I run this I get this error:

request = <SubRequest 'lower' for <Function 'test_all[lower]'>>

@pytest.fixture(params=[1, 2, 3])
def lower(request):
> return "i" * request.param
E AttributeError: 'SubRequest' object has no attribute 'param'


... and the same error for upper().

What did I do wrong?

How can I fix this?

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