autoflake8 removes unused imports and unused variables from Python code. It makes use of pyflakes to do this.
autoflake8 also removes useless
It’s a maintained fork of autoflake.
Differences from autoflake
This fork of autoflake removed some features from autoflake and modified certain behaviors. The main motivations for those changes is the idea that autoflake8 is built for users of flake8 and it’s assumed that if you’re using autoflake8, you’re also using flake8. This motivated the removal of the flags
--remove-all-unused-imports: if you want to preserve an import for its side-effect, use
autoflake8 also supports load from
stdin and printing to
stdout, which makes it very easy for users to integrate with their custom editors.
Finally, a big difference is that
autoflake8 exits with status 1 when it detects issues/rewrite files. For editor integration, the new flag
--exit-zero-even-if-changed can be used. When that flag is defined,
autoflake8 will return status 0 even when it modifies files.
In terms of future plans, we also plan to eventually stop using regular expressions and rely on actual AST rewriting to fix issues reported by flake8.
Running autoflake8 on the below example:
$ autoflake8 --in-place --remove-unused-variables example.py
import math import re import os import random import multiprocessing import grp, pwd, platform import subprocess, sys def foo(): from abc import ABCMeta, WeakSet try: import multiprocessing print(multiprocessing.cpu_count()) except ImportError as exception: print(sys.version) return math.pi
import math import sys def foo(): try: import multiprocessing print(multiprocessing.cpu_count()) except ImportError: print(sys.version) return math.pi
$ pip install --upgrade autoflake8
Using as a pre-commit hook
autoflake8 can be used as a pre-commit hook. See pre-commit for instructions.
- repo: https://github.com/fsouza/autoflake8 rev: v0.2.1 hooks: - id: autoflake8
To remove unused variables, use the
Below is the full listing of options:
usage: autoflake8 [-h] [-c] [-r] [--exclude globs] [--expand-star-imports] [--remove-duplicate-keys] [--remove-unused-variables] [--version] [-v] [--exit-zero-even-if-changed] [-i | -s] files [files ...] positional arguments: files files to format optional arguments: -h, --help show this help message and exit -c, --check return error code if changes are needed -r, --recursive drill down directories recursively --exclude globs exclude file/directory names that match these comma-separated globs --expand-star-imports expand wildcard star imports with undefined names; this only triggers if there is only one star import in the file; this is skipped if there are any uses of `__all__` or `del` in the file --remove-duplicate-keys remove all duplicate keys in objects --remove-unused-variables remove unused variables --version show program's version number and exit -v, --verbose print more verbose logs (you can repeat `-v` to make it more verbose) --exit-zero-even-if-changed -i, --in-place make changes to files instead of printing diffs -s, --stdout print changed text to stdout. defaults to true when formatting stdin, or to false otherwise
To run the unit tests:
$ poetry run pytest
There is also a fuzz test, which runs against any collection of given Python files. It tests autoflake8 against the files and checks how well it does by running pyflakes on the file before and after. The test fails if the pyflakes results change for the worse. (This is done in memory. The actual files are left untouched):
Excluding specific lines
It might be the case that you have some imports for their side effects, even if you are not using them directly in that file.
That is common, for example, in Flask based applications. In where you import Python modules (files) that imported a main
app, to have them included in the routes.
from .endpoints import role, token, user, utils
To prevent that, without having to exclude the entire file, you can add a
# noqa comment at the end of the line, like:
from .endpoints import role, token, user, utils # noqa
That line will instruct
autoflake8 to let that specific line as is.