"duplicate parametrization" errors with pytest dev

[braingram]

I noticed some new failures with pytest-dev where collection errors are occuring with "duplicate parametrization" messages.

Here's a minimal example:

import pytest


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


@pytest.fixture
def val(request):
    return int(request.param)


@pytest.mark.parametrize(
    "val, target",
    [
        ("1", 1),
        ("2", 2),
    ],
    indirect=["val"],
)
def test_foo(val, target):
    assert str(val) == str(target)

Starting with commit d56b1af
this triggers an error:

test_bar.py::test_foo: duplicate parametrization of 'target'

Prior to that commit the file runs as expected:

test_bar.py::test_foo[1-1] PASSED                                                                                                                                                                                 
test_bar.py::test_foo[2-2] PASSED

In case it's useful here is the link to a run that was impacted by this bug:
https://github.com/asdf-format/asdf/actions/runs/19420723535/job/55557560788#step:10:98

Thanks and let me know if there is any more information that would be helpful.

pip list output:

Package   Version                Editable project location
--------- ---------------------- ------------------------------------------------
iniconfig 2.3.0
packaging 25.0
pip       24.0
pluggy    1.6.0
Pygments  2.19.2
pytest    9.1.0.dev74+gbbb0c0778

[notice] A new release of pip is available: 24.0 -> 25.3
[notice] To update, run: python3.12 -m pip install --upgrade pip

Tested on mac os and python 3.12 (error in the above linked CI run was on linux and python 3.11).

[bluetech]

Thanks for testing pytest main, and providing an MRE and bisect on top!

I think I see the issue, hopefully will send a fix soon.