================
flake8-no-pep420
================
.. image:: https://img.shields.io/github/actions/workflow/status/adamchainz/flake8-no-pep420/main.yml?branch=main&style=for-the-badge
:target: https://github.com/adamchainz/flake8-no-pep420/actions?workflow=CI
.. image:: https://img.shields.io/pypi/v/flake8-no-pep420.svg?style=for-the-badge
:target: https://pypi.org/project/flake8-no-pep420/
.. image:: https://img.shields.io/badge/code%20style-black-000000.svg?style=for-the-badge
:target: https://github.com/psf/black
.. image:: https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white&style=for-the-badge
:target: https://github.com/pre-commit/pre-commit
:alt: pre-commit
A `flake8 <https://flake8.readthedocs.io/en/latest/index.html>`_ plugin to ban `PEP-420 <https://www.python.org/dev/peps/pep-0420/>`__ implicit namespace packages.
Requirements
============
Python 3.8 to 3.12 supported.
Installation
============
First, install with ``pip``:
.. code-block:: sh
python -m pip install flake8-no-pep420
Second, if you define Flake8’s ``select`` setting, add the ``INP`` prefix to it.
Otherwise, the plugin should be active by default.
----
**Linting a Django project?**
Check out my book `Boost Your Django DX <https://adamchainz.gumroad.com/l/byddx>`__ which covers Flake8 and many other code quality tools.
----
Rationale
=========
Implicit namespace packages are directories of Python files without an ``__init__.py``.
They’re valid and importable, but they break *many* tools, such as:
* `unittest test discovery <https://bugs.python.org/issue23882>`__ (and by extension, Django’s test runner)
* `Coverage.py <https://github.com/nedbat/coveragepy/issues/1024>`__
* Mypy without its `--namespace-packages option <https://mypy.readthedocs.io/en/latest/command_line.html#import-discovery>`__
* `pytest <https://github.com/pytest-dev/pytest/issues/5147>`__
In most cases, tools fail silently, which can lead to a false sense of security:
* Tests may look legitimate but never run
* Code may be untested but not appear in coverage statistics
* Types may never be checked
PEP-420’s algorithm is non-trivial which is probably why such tools haven’t (yet) implemented it.
Rules
=====
INP001: File is part of an implicit namespace package. Add __init__.py?
-----------------------------------------------------------------------
flake8-no-pep420 will trigger this on the first line of any file that sits in a directory without an ``__init__.py`` file.
Often projects have a few root files *not* in packages, for which an ``__init__.py`` file should not be added.
For example, Django projects normally have a ``manage.py`` file in the root of their repository.
In these cases you can ignore the ``INP001`` error.
It’s possible to use ``# noqa: INP001`` to ignore the error in-line, but this isn’t possible if the first line is a `shebang <https://en.wikipedia.org/wiki/Shebang_(Unix)>`__, such as in Django’s ``manage.py``.
In such cases it’s preferable to use Flake8’s `per-file-ignores option <https://flake8.pycqa.org/en/latest/user/options.html#cmdoption-flake8-per-file-ignores>`__, for example in ``setup.cfg``:
.. code-block:: ini
[flake8]
# ...
per-file-ignores =
manage.py:INP001
Raw data
{
"_id": null,
"home_page": "https://github.com/adamchainz/flake8-no-pep420",
"name": "flake8-no-pep420",
"maintainer": "",
"docs_url": null,
"requires_python": ">=3.8",
"maintainer_email": "",
"keywords": "flake8",
"author": "Adam Johnson",
"author_email": "me@adamj.eu",
"download_url": "https://files.pythonhosted.org/packages/1a/56/8982259cb646a7f13ebe7781db7227e86291cf64c08b3eb9aba247b25901/flake8_no_pep420-2.7.0.tar.gz",
"platform": null,
"description": "================\nflake8-no-pep420\n================\n\n.. image:: https://img.shields.io/github/actions/workflow/status/adamchainz/flake8-no-pep420/main.yml?branch=main&style=for-the-badge\n :target: https://github.com/adamchainz/flake8-no-pep420/actions?workflow=CI\n\n.. image:: https://img.shields.io/pypi/v/flake8-no-pep420.svg?style=for-the-badge\n :target: https://pypi.org/project/flake8-no-pep420/\n\n.. image:: https://img.shields.io/badge/code%20style-black-000000.svg?style=for-the-badge\n :target: https://github.com/psf/black\n\n.. image:: https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white&style=for-the-badge\n :target: https://github.com/pre-commit/pre-commit\n :alt: pre-commit\n\nA `flake8 <https://flake8.readthedocs.io/en/latest/index.html>`_ plugin to ban `PEP-420 <https://www.python.org/dev/peps/pep-0420/>`__ implicit namespace packages.\n\nRequirements\n============\n\nPython 3.8 to 3.12 supported.\n\nInstallation\n============\n\nFirst, install with ``pip``:\n\n.. code-block:: sh\n\n python -m pip install flake8-no-pep420\n\nSecond, if you define Flake8\u2019s ``select`` setting, add the ``INP`` prefix to it.\nOtherwise, the plugin should be active by default.\n\n----\n\n**Linting a Django project?**\nCheck out my book `Boost Your Django DX <https://adamchainz.gumroad.com/l/byddx>`__ which covers Flake8 and many other code quality tools.\n\n----\n\nRationale\n=========\n\nImplicit namespace packages are directories of Python files without an ``__init__.py``.\nThey\u2019re valid and importable, but they break *many* tools, such as:\n\n* `unittest test discovery <https://bugs.python.org/issue23882>`__ (and by extension, Django\u2019s test runner)\n* `Coverage.py <https://github.com/nedbat/coveragepy/issues/1024>`__\n* Mypy without its `--namespace-packages option <https://mypy.readthedocs.io/en/latest/command_line.html#import-discovery>`__\n* `pytest <https://github.com/pytest-dev/pytest/issues/5147>`__\n\nIn most cases, tools fail silently, which can lead to a false sense of security:\n\n* Tests may look legitimate but never run\n* Code may be untested but not appear in coverage statistics\n* Types may never be checked\n\nPEP-420\u2019s algorithm is non-trivial which is probably why such tools haven\u2019t (yet) implemented it.\n\nRules\n=====\n\nINP001: File is part of an implicit namespace package. Add __init__.py?\n-----------------------------------------------------------------------\n\nflake8-no-pep420 will trigger this on the first line of any file that sits in a directory without an ``__init__.py`` file.\n\nOften projects have a few root files *not* in packages, for which an ``__init__.py`` file should not be added.\nFor example, Django projects normally have a ``manage.py`` file in the root of their repository.\nIn these cases you can ignore the ``INP001`` error.\nIt\u2019s possible to use ``# noqa: INP001`` to ignore the error in-line, but this isn\u2019t possible if the first line is a `shebang <https://en.wikipedia.org/wiki/Shebang_(Unix)>`__, such as in Django\u2019s ``manage.py``.\nIn such cases it\u2019s preferable to use Flake8\u2019s `per-file-ignores option <https://flake8.pycqa.org/en/latest/user/options.html#cmdoption-flake8-per-file-ignores>`__, for example in ``setup.cfg``:\n\n.. code-block:: ini\n\n [flake8]\n # ...\n per-file-ignores =\n manage.py:INP001\n",
"bugtrack_url": null,
"license": "MIT",
"summary": "A flake8 plugin to ban PEP-420 implicit namespace packages.",
"version": "2.7.0",
"project_urls": {
"Changelog": "https://github.com/adamchainz/flake8-no-pep420/blob/main/CHANGELOG.rst",
"Homepage": "https://github.com/adamchainz/flake8-no-pep420",
"Mastodon": "https://fosstodon.org/@adamchainz",
"Twitter": "https://twitter.com/adamchainz"
},
"split_keywords": [
"flake8"
],
"urls": [
{
"comment_text": "",
"digests": {
"blake2b_256": "602e16f8f320a662c14132b67f11601fdd3a5834eed9abcbca45e29b7f0df589",
"md5": "3d1cb8f1fbcdac47d045f9f7d5bf2149",
"sha256": "018bbe0fba039444689d02a0857310b62b90ff9bf737aff27e0b847ec7eb9ba3"
},
"downloads": -1,
"filename": "flake8_no_pep420-2.7.0-py3-none-any.whl",
"has_sig": false,
"md5_digest": "3d1cb8f1fbcdac47d045f9f7d5bf2149",
"packagetype": "bdist_wheel",
"python_version": "py3",
"requires_python": ">=3.8",
"size": 4732,
"upload_time": "2023-07-10T13:46:38",
"upload_time_iso_8601": "2023-07-10T13:46:38.222525Z",
"url": "https://files.pythonhosted.org/packages/60/2e/16f8f320a662c14132b67f11601fdd3a5834eed9abcbca45e29b7f0df589/flake8_no_pep420-2.7.0-py3-none-any.whl",
"yanked": false,
"yanked_reason": null
},
{
"comment_text": "",
"digests": {
"blake2b_256": "1a568982259cb646a7f13ebe7781db7227e86291cf64c08b3eb9aba247b25901",
"md5": "b498baf7bcfb44bc98d011df4af2ef4e",
"sha256": "a1b6db4de355b87f8189714e68785a7c6a2d61d94f3e937b6cee336953f7d703"
},
"downloads": -1,
"filename": "flake8_no_pep420-2.7.0.tar.gz",
"has_sig": false,
"md5_digest": "b498baf7bcfb44bc98d011df4af2ef4e",
"packagetype": "sdist",
"python_version": "source",
"requires_python": ">=3.8",
"size": 5259,
"upload_time": "2023-07-10T13:46:39",
"upload_time_iso_8601": "2023-07-10T13:46:39.637828Z",
"url": "https://files.pythonhosted.org/packages/1a/56/8982259cb646a7f13ebe7781db7227e86291cf64c08b3eb9aba247b25901/flake8_no_pep420-2.7.0.tar.gz",
"yanked": false,
"yanked_reason": null
}
],
"upload_time": "2023-07-10 13:46:39",
"github": true,
"gitlab": false,
"bitbucket": false,
"codeberg": false,
"github_user": "adamchainz",
"github_project": "flake8-no-pep420",
"travis_ci": false,
"coveralls": false,
"github_actions": true,
"tox": true,
"lcname": "flake8-no-pep420"
}
JSON
