An error while trying to execute tests on python 3.10 with pytest

Question

If I try to execute tests using pytest with python 3.10 I got the following error:

TypeError: required field "lineno" missing from alias

Google says it's a known problem, but I found no way to solve it.
Tests start fine if I launch them with 3.9

score 90 · Answer 1 · edited Jan 02 '22 at 09:56

90

This issue seems to be fixed in pytest version 6.2.5.

edited Jan 02 '22 at 09:56

tutuDajuju

answered Oct 14 '21 at 10:36

Lewi Uberg

1

I am using pytest version 7.1.2 and still have same issue, how can I fix this problem locally? – John May 18 '22 at 17:13
3

@John I was able to fix this issue by upgrading pytest to version `7.1.2`. – Matt Welke Jun 18 '22 at 05:00
weird stuff going on mate – John Jun 20 '22 at 07:15
12

This solved the problem for me. I ran `poetry add --dev pytest@latest` as `poetry new` constrained `pytest` to `^5.2` by default. – Doom5 Jul 13 '22 at 01:35

Benyamin Jafari · Answer 2 · 2022-11-16T13:12:35.203

33

Just upgrade the pytest PyPI package:

pip install -U pytest

edited Nov 16 '22 at 13:12

answered Apr 25 '22 at 22:11

Benyamin Jafari

I still have same problem, is this normal output after this call? - $ pip install -U pytest Defaulting to user installation because normal site-packages is not writeable, others are that Requirement is already satisfied – John May 18 '22 at 17:27
2

@John I guess your problem is related to the `pip` itself. Try to update the `pip` via `python -m pip install -U pip` or install the `pytest` through `python -m pip install -U pytest` – Benyamin Jafari May 18 '22 at 21:10
2

I think this is the correct answer (that the solution is to update pytest) but the command to run can be improved. Since we're using poetry to manage our project's dependencies, including its dev dependencies, we should run `poetry remove --dev pytest && poetry add --dev pytest`, which will remove whichever version of pytest was added to the project when it was created and then add the latest version. For me, that meant going from `5.4.3` to `7.1.2`. This process also removed the old transitive dependencies of pytest and then added the new transitive dependencies for the new version. – Matt Welke Jun 18 '22 at 04:58
When I did the above steps, and then ran `poetry run pytest`, it worked for me. Since this was a brand new project with no source code yet, and just the initial, automatically-created test, my output said: `1 passed in 0.01s` – Matt Welke Jun 18 '22 at 04:59

score 0 · Answer 3 · answered Jan 07 '23 at 22:35

0

Meanwhile...I was getting this error during

python3 setup.py pytest

in a library. When I did the following:

pytest -q tests/test_mypackage.py

The error lost, and I got the tests running.

answered Jan 07 '23 at 22:35

tolga

3 Answers3