pytest-dev / pytest-dev/pytest

`pytest.approx()` incorrectly flags nested sequences as unequal

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topic: approx
Dominant language
Python
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Description

Consider this:

>>> a = [(1.20000000000001,)]
>>> b = [(1.2,)]
>>> a == pytest.approx(b)
False

On the other hand:

>>> a[0] == pytest.approx(b[0])
True

So I am assuming it is thrown off by the nested sequences.

I am using pytest 8.0.0.

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Research direction

Reproduce the examples with pytest 8.0.0, then trace how pytest.approx compares nested sequences. Add a regression test covering the nested tuple case and verify that the outer comparison matches the inner comparison result.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
testing-qa
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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