flake8-plone-hasattr

Flake8 Plone hasattr plugin

Python standard hasattr is considered harmful (within Plone projects).

The (hidden) problem with hasattr is that it swallows exceptions, which in your normal business logic you really don’t want to.

Specially in Plone context that could mean swallowing a database error, or a permission exception, etc.

Take, for instance, the following code:

>>> class Foo(object):
...     @property
...     def my_attr(self):
...         raise ValueError('nope, nope, nope')
...
>>> bar = Foo()
>>> bar.my_attr
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 4, in my_attr
ValueError: nope, nope, nope
>>> hasattr(Foo, 'my_attr')
True
>>> hasattr(bar, 'my_attr')
False

One should rather do:

>>> getattr(bar, 'my_attr', None)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 4, in my_attr
ValueError: nope, nope, nope

Or in case you want to handle an exception:

>>> try:
...     value = getattr(bar, 'my_attr', None)
... exception ValueError:
...     value = None

This plugin is based on a python checker that was in plone.recipe.codeanalysis.

Install

Install with pip:

$ pip install flake8-plone-hasattr

Requirements

Python 3.8, 3.9, 3.10, 3.11 and pypy3
flake8

License

GPL 2.0

Release files for flake8-plone-hasattr 1.2.0

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for flake8-plone-hasattr 1.2.0
File	Size	Uploaded
flake8_plone_hasattr-1.2.0.tar.gz	13.4 kB	Oct 25, 2025	Details

Built distribution (wheel)

Table of built distributions (wheels) for flake8-plone-hasattr 1.2.0
File	Interpreter	ABI	Platform	Reset
flake8_plone_hasattr-1.2.0-py3-none-any.whl 16.9 kB Oct 25, 2025	Python 3	none	any	Details

Total release size: 30.3 kB

Release files / flake8_plone_hasattr-1.2.0.tar.gz

Download URL	flake8_plone_hasattr-1.2.0.tar.gz
Size	13.4 kB
Tags	Source
SHA-256 checksum How to use checksums	`7ab10489392a1d3cbea34424093e21b3a4ff5ecfd75a915cda0ba79140c032c4`
BLAKE2b-256 checksum How to use checksums	`9c413d81980010207e30d396d050278375ff5eef98b73f948677de7281560329`
Upload date	Oct 25, 2025
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.13.7`

Release files / flake8_plone_hasattr-1.2.0-py3-none-any.whl

Download URL	flake8_plone_hasattr-1.2.0-py3-none-any.whl
Size	16.9 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`668a8109768e4caad59207ba591fc429968fbf218d40e665d839f7230188a5c8`
BLAKE2b-256 checksum How to use checksums	`48e0c67089042cfe27175fbcb663da42af060b32c3408acd6d887d894e3ad212`
Upload date	Oct 25, 2025
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.13.7`