pytest 9.02 TypeError, 9.01 works

[tquinn2]

• a detailed description of the bug or problem you are having
• output of pip list from the virtual environment you are using
• pytest and operating system versions
• minimal example if possible

Description

When running pytest version 9.0.2 I get the following errors, related to python's AST. I think the key error message here is INTERNALERROR> TypeError: required field "col_offset" missing from stmt. Reverting to pytest version 9.0.1 fixes this issue.

INTERNALERROR> Traceback (most recent call last):
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\main.py", line 314, in wrap_session
INTERNALERROR>     config._do_configure()
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\config\__init__.py", line 1159, in _do_configure
INTERNALERROR>     self.hook.pytest_configure.call_historic(kwargs=dict(config=self))
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\pluggy\_hooks.py", line 534, in call_historic
INTERNALERROR>     res = self._hookexec(self.name, self._hookimpls.copy(), kwargs, False)
INTERNALERROR>           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\pluggy\_manager.py", line 120, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
INTERNALERROR>            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\pluggy\_callers.py", line 167, in _multicall
INTERNALERROR>     raise exception
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\pluggy\_callers.py", line 121, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>           ^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\terminal.py", line 304, in pytest_configure
INTERNALERROR>     config.pluginmanager.import_plugin("terminalprogress")
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\config\__init__.py", line 879, in import_plugin
INTERNALERROR>     __import__(importspec)
INTERNALERROR>   File "<frozen importlib._bootstrap>", line 1354, in _find_and_load
INTERNALERROR>   File "<frozen importlib._bootstrap>", line 1325, in _find_and_load_unlocked
INTERNALERROR>   File "<frozen importlib._bootstrap>", line 929, in _load_unlocked
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\assertion\rewrite.py", line 188, in exec_module
INTERNALERROR>     source_stat, co = _rewrite_test(fn, self.config)
INTERNALERROR>                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "C:\temp\pytest_demo\testing-demo\.venv\Lib\site-packages\_pytest\assertion\rewrite.py", line 359, in _rewrite_test
INTERNALERROR>     co = compile(tree, strfn, "exec", dont_inherit=True)
INTERNALERROR>          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR> TypeError: required field "col_offset" missing from stmt

pip list

colorama     0.4.6
iniconfig    2.3.0
packaging    26.0
pluggy       1.6.0
pygments     2.19.2
pytest       9.0.2
testing-demo 0.1.0   C:\temp\pytest_demo\testing-demo

Versions

Python: 3.13.1
pytest: 9.0.2
OS: Windows 10 (22H2)

Minimal example

# tests/my_test.py

import pytest

def test_add_with_fixture():
    assert True

I also tried this:
https://pydevtools.com/handbook/tutorial/setting-up-testing-with-pytest-and-uv/

[EmmanuelNiyonshuti]

I tried the example using pytest 9.0.2 with python 3.13 on Ubuntu 24.04 and it worked fine. Might be Windows-specific!

[bluetech]

In 9.0.2 we made a change that made the terminalprogress plugin load a little later and now it (unnecessarily, but harmlessly) rewritten for assertions. But maybe the change causes some kind of pyc confusion. If you start with pytest 9.0.2 and remove all __pycache__ directories/.pyc files does this still happen?

[pattersonzoe84-art]

Thanks for the tips! I’ll try removing all __pycache__ directories and .pyc files on Windows and see if that resolves it.

…

On Sat, Mar 28, 2026, 6:37 PM Ran Benita ***@***.***> wrote: *bluetech* left a comment (pytest-dev/pytest#14334) <#14334 (comment)> In 9.0.2 we made a change that made the terminalprogress plugin load a little later and now it (unnecessarily, but harmlessly) rewritten for assertions. But maybe the change causes some kind of pyc confusion. If you start with pytest 9.0.2 and remove all __pycache__ directories/.pyc files does this still happen? — Reply to this email directly, view it on GitHub <#14334?email_source=notifications&email_token=B72K3KK5RL56AVB2R36BMR34TBO2XA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMJUHEYDGMBVGA22M4TFMFZW63VKON2WE43DOJUWEZLEUVSXMZLOOSWGM33PORSXEX3DNRUWG2Y#issuecomment-4149030505>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/B72K3KOEHG622TFQQGHT4D34TBO2XAVCNFSM6AAAAACXDIY3L2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DCNBZGAZTANJQGU> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[tquinn2]

Deleting pycache did not appear to have any effect.

It looks like the issue is related to uv. If I do this:

uv init testing-demo --package
uv run pytest

Then I get the errors reported above. Without changing anything, I can also try activating the virtual environment, and running pytest, which results in the same effect, if I am using pytest 9.0.2.

.venv\Scripts\activate
pytest

However, I get no errors from doing the following:

python -m venv .venv
.venv\Scripts\activate
pytest

[bluetech]

Hmm I don't know what's going on and I don't have a windows machine to debug on, but I will try to think about it. The error itself is pretty strange as well.

Do you think you could upload the following file here? I'd like to inspect it.

.venv/lib/python3.13/site-packages/_pytest/__pycache__/terminalprogress.cpython-313-pytest-9.0.2.pyc

[tquinn2]

I wish I could go without a windows machine myself. In the "uv" directory, there is no terminalprogress.cpython-313-pytest-9.0.2.pyc file. However, in the directory where I manually created my virtual environment the file is present. (On my machine the file path is .venv\Lib\site-packages_pytest_pycache_\terminalprogress.cpython-313-pytest-9.0.2.pyc). I can upload the .pyc file from the functioning directory, but I don't know if that would be helpful.

Here is a copy of the contents of the .venv/Lib/site-packages/_pytest/pycache from the "uv" directory.

init.cpython-312.pyc
_argcomplete.cpython-312.pyc
_version.cpython-312.pyc
cacheprovider.cpython-312.pyc
capture.cpython-312.pyc
compat.cpython-312.pyc
debugging.cpython-312.pyc
deprecated.cpython-312.pyc
doctest.cpython-312.pyc
faulthandler.cpython-312.pyc
fixtures.cpython-312.pyc
freeze_support.cpython-312.pyc
helpconfig.cpython-312.pyc
hookspec.cpython-312.pyc
junitxml.cpython-312.pyc
legacypath.cpython-312.pyc
logging.cpython-312.pyc
main.cpython-312.pyc
monkeypatch.cpython-312.pyc
nodes.cpython-312.pyc
outcomes.cpython-312.pyc
pastebin.cpython-312.pyc
pathlib.cpython-312.pyc
pytester.cpython-312.pyc
python.cpython-312.pyc
python_api.cpython-312.pyc
raises.cpython-312.pyc
recwarn.cpython-312.pyc
reports.cpython-312.pyc
runner.cpython-312.pyc
scope.cpython-312.pyc
setuponly.cpython-312.pyc
setupplan.cpython-312.pyc
skipping.cpython-312.pyc
stash.cpython-312.pyc
stepwise.cpython-312.pyc
subtests.cpython-312.pyc
terminal.cpython-312.pyc
threadexception.cpython-312.pyc
timing.cpython-312.pyc
tmpdir.cpython-312.pyc
tracemalloc.cpython-312.pyc
unittest.cpython-312.pyc
unraisableexception.cpython-312.pyc
warning_types.cpython-312.pyc
warnings.cpython-312.pyc

[bluetech]

Thanks. The problematic (uv) directory is using Python 3.12?

[tquinn2]

Sorry, I was switching between python 3.12 and 3.13 just to see if that made any difference. Both result in the same error messages being produced.

I switched back to 3.13, deleted the pytest __pycache__, ran uv run pytest and the test generated the same errors and pytest __pycache__ looks the same.

__init__.cpython-313.pyc
_argcomplete.cpython-313.pyc
_version.cpython-313.pyc
cacheprovider.cpython-313.pyc
capture.cpython-313.pyc
compat.cpython-313.pyc
debugging.cpython-313.pyc
deprecated.cpython-313.pyc
doctest.cpython-313.pyc
faulthandler.cpython-313.pyc
fixtures.cpython-313.pyc
freeze_support.cpython-313.pyc
helpconfig.cpython-313.pyc
hookspec.cpython-313.pyc
junitxml.cpython-313.pyc
legacypath.cpython-313.pyc
logging.cpython-313.pyc
main.cpython-313.pyc
monkeypatch.cpython-313.pyc
nodes.cpython-313.pyc
outcomes.cpython-313.pyc
pastebin.cpython-313.pyc
pathlib.cpython-313.pyc
pytester.cpython-313.pyc
python.cpython-313.pyc
python_api.cpython-313.pyc
raises.cpython-313.pyc
recwarn.cpython-313.pyc
reports.cpython-313.pyc
runner.cpython-313.pyc
scope.cpython-313.pyc
setuponly.cpython-313.pyc
setupplan.cpython-313.pyc
skipping.cpython-313.pyc
stash.cpython-313.pyc
stepwise.cpython-313.pyc
subtests.cpython-313.pyc
terminal.cpython-313.pyc
threadexception.cpython-313.pyc
timing.cpython-313.pyc
tmpdir.cpython-313.pyc
tracemalloc.cpython-313.pyc
unittest.cpython-313.pyc
unraisableexception.cpython-313.pyc
warning_types.cpython-313.pyc
warnings.cpython-313.pyc

[tquinn2]

It appears that it was some type of versioning error. When I looked at .venv/Lib/site-packages/_pytest/assertion/rewrite.py I saw that it was using col_regAddr instead of col_offset. I deleted my .venv and tried again. I didn't get any errors. I'm not sure why this was happening before. My pytest version was 9.0.2 according to pip list. It looks like it's probably a uv issue

[pattersonzoe84-art]

Ok, I'll look into it.

…

On Mon, Mar 30, 2026, 3:51 PM tquinn2 ***@***.***> wrote: *tquinn2* left a comment (pytest-dev/pytest#14334) <#14334 (comment)> It appears that it was some type of versioning error. When I looked at .venv/Lib/site-packages/_pytest/assertion/rewrite.py I saw that it was using col_regAddr instead of col_offset. I deleted my .venv and tried again. I didn't get any errors. I'm not sure why this was happening before. My pytest version was 9.0.2 according to pip list. It looks like it's probably a uv issue — Reply to this email directly, view it on GitHub <#14334?email_source=notifications&email_token=B72K3KOMQESL2X2P7MXWWV34TLM5BA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMJVHAYTAMJYGQ3KM4TFMFZW63VHMNXW23LFNZ2KKZLWMVXHJLDGN5XXIZLSL5RWY2LDNM#issuecomment-4158101846>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/B72K3KK74NTZNI7VOXM5Q6L4TLM5BAVCNFSM6AAAAACXDIY3L2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DCNJYGEYDCOBUGY> . You are receiving this because you commented.Message ID: ***@***.***>