cython-lint
Everything flake8 used to do (by accident), plus much more.
A tool and pre-commit hook to lint Cython files.
Used by
Here's some major projects using cython-lint - is yours missing? Feel free to open a pull request!
- arrow-adbc
- ansible-pylibssh
- arrow
- CuPy
- dpctl
- frozenlist
- mkl_fft
- mkl-service
- NumPy
- open library
- pandas
- pymatgen
- PyRFC
- RAPIDS cuspatial
- RAPIDS cudf
- RAPIDS Memory Manager
- sagemath/sage
- scikit-image
- scikit-learn
- scipy
- spaCy
- yarl
- yt
Installation
$ pip install cython-lint
Usage as a pre-commit hook
See pre-commit for instructions
Sample .pre-commit-config.yaml:
- repo: https://github.com/MarcoGorelli/cython-lint
rev: v0.22.0
hooks:
- id: cython-lint
- id: double-quote-cython-strings
Command-line example
$ cython-lint my_file_1.pyx my_file_2.pyx
my_file_1.pyx:54:5: 'get_conversion_factor' imported but unused
my_file_2.pyx:1112:38: 'mod' defined but unused (try prefixing with underscore?)
my_file_3.pyx:4:9: dangerous default value!
my_file_3.pyx:5:9: comma after base type in definition
Configuration
The following configuration options are available:
- exclude lines by including a
# no-cython-lintcomment (analogous to# noqainflake8);
as well as the following command-line arguments:
--max-line-lengthto control the maximum line length used by pycodestyle;--no-pycodestyleif you don't want the pycodestyle checks;--ban-relative-importsif you want to ban relative imports;--ignoreif you want to ignore some specific pycodestyle checks;--filesto pass a Regex pattern with which to match files to include;--excludeto pass a Regex pattern with which to match files to exclude.
Configuration can be set project-wide in a .cython-lint.toml or pyproject.toml file
at the root of the project. Here's an example:
[tool.cython-lint]
max-line-length = 88
ignore = ['E503', 'E504']
exclude = 'my_project/excluded_cython_file.pyx'
Which checks are implemented?
- assert statement with tuple condition (always true...)
- comma after base type definition (e.g.
cdef ndarray, arr) - comparison between constants
- dangerous default value
- dict key repeated
- dict key variable repeated
- f-string without placeholders
- if-statement with tuple condition (always true...)
- late-binding closures https://docs.python-guide.org/writing/gotchas/#late-binding-closures
- loop control variable 'i' not used within the loop body (if this is intended, start the name with an underscore)
- outer loop variable name overwritten by inner loop variable name
- pointless string statement
pycodestylenitpicks (which you can turn off with--no-pycodestyle)- repeated element in set
.strip,.rstrip, or.lstripused with repeated characters- unnecessary list index lookup
- unnecessary import alias
- variable defined but unused
- variable imported but unused
- unnecessary
list/set/dict+ generator (just use a comprehension)
In addition, the following automated fixers are implemented:
- double-quote-cython-strings (replace single quotes with double quotes, like the
blackformatter does)
More to come! Requests welcome!
1 maintainer
Metadata
1 maintainer
Release files for cython-lint 0.22.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| cython_lint-0.22.0.tar.gz | 32.5 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| cython_lint-0.22.0-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 49.4 kB
Release files / cython_lint-0.22.0.tar.gz
| Download URL | cython_lint-0.22.0.tar.gz |
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| Size | 32.5 kB |
| Tags | Source |
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| Tags | Python 3 |
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| Uploaded via |
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