ImportError: cannot import name 'etree' from 'lxml'

[Timple]

lxml or etree might not be specified as dependencies of [toml] and [cmake]?

I see it in the pyproject.toml but no in pre-commit-hooks.yaml

Polymath Code Standard [cmake]...........................................Failed
- hook id: polymath-cmake
- exit code: 1

Traceback (most recent call last):
  File "/home/tim/.cache/pre-commit/noble/repoha3dzytc/py_env-python3/bin/polymath_code_standard", line 3, in <module>
    from polymath_code_standard.runner import main
  File "/home/tim/.cache/pre-commit/noble/repoha3dzytc/py_env-python3/lib/python3.12/site-packages/polymath_code_standard/runner.py", line 20, in <module>
    importlib.import_module(f'.checkers.{_mod.name}', package=__package__)
  File "/usr/lib/python3.12/importlib/__init__.py", line 90, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/tim/.cache/pre-commit/noble/repoha3dzytc/py_env-python3/lib/python3.12/site-packages/polymath_code_standard/checkers/xml.py", line 6, in <module>
    from lxml import etree
ImportError: cannot import name 'etree' from 'lxml' (/home/tim/repos/robot/.pixi/envs/default/lib/python3.14/site-packages/lxml/__init__.py)

[emersonknapp]

@Timple I think this is a symptom of Pixi setting PYTHONPATH in your environment, which takes precedence over the virtualenv used by pre-commit.

I have a solution that could narrow this error down to just the checks that are actually broken because of the problem, but can't think of a solution that would make the whole check suite work for you.

I may be wrong, but my understanding is that PYTHONPATH is going to ruin anything going on in a virtual environment. The venv mechanism appends its site-packages to the end of sys.path, which means whatever is in PYTHONPATH will always beat it, the venv can't win.

See

/home/tim/repos/robot/.pixi/envs/default/lib/python3.14/site-packages/lxml/__init__.py

But we do specify the lxml dependency - it's just being clobbered by your Pixi version.

[dhirschfeld]

There's some advice on setting up pre-commit to work with pixi in this PR:
https://github.com/Yacine-DH/pixi/blob/docs/git-hooks/docs/integration/third_party/git_hooks.md#pre-commit

• docs: add guide for using pixi with lefthook, pre-commit, and prek (#… prefix-dev/pixi#5891

[emersonknapp]

@dhirschfeld thanks for the context - I'd be willing to accept documentation update here for Pixi users. It seems like instead of using the .pre-commit-hooks.yaml definitions, you instead would have to duplicate them for the local call, but that's entirely possible.

This package is not yet published to a package index for use in your Pixi environment, but I'm also not opposed to a proposal for that to support the use case - I just won't have bandwidth to plan/do it myself, but can support.

[Timple]

I'm not a fan of making them all local hooks. We're still not fully pixi-enabled.

But I should have looked closer, the dependency is indeed present. When I solve it I'll leave a pointer here!