pytest-dev / pytest-dev/pytest

mypy plugin for `@mark.parametrize`

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#9,334 3 comments 5 reactions 0 assignees View on GitHub

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type: proposal
Dominant language
Python
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Avg merge
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Merged PRs (30d)
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Description

The idea is that a plugin would allow the arguments to the @pytest.mark.parametrize decorator to be type-checked.

For example:

import pytest

@pytest.mark.parametrize(
    "arg",
    [
        123,        # correct type int
        456.789,    # wrong type float, mypy plugin to complain
    ]
)
def test_foo(
    arg: int   # plugin reads `int` annotation here
) -> None:
    ...

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Research direction

The issue names no repository files, tests, or entry points. Start by identifying how pytest.mark.parametrize is implemented and how mypy plugins receive function annotations; done would include type-checking the demonstrated mismatched float argument.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
testing
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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