Registry / testing / flake8-annotations

flake8-annotations

library3.2.0pypypi✓ verified 29d ago

Flake8 Annotations is a plugin for Flake8 that enforces the presence and style of PEP 3107-style function annotations in Python code. It helps maintain consistent typing practices by flagging missing or incorrect type annotations. The current version is 3.2.0, and the project is actively maintained with regular updates addressing Python and Flake8 compatibility.

testing

pip install flake8 flake8-annotations

github ↗package ↗docs ↗changelog ↗

INSTALL

IMPORT

SIG · FLAKE8-ANNOTATIONS

flake8-annotations

testingpythonv3.2.0

Install

1.8s avg

Import

—

Disk

18MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v3.2.0 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.000s · 19.4MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 1.8s · import 0.000s · 20MB

18MB installed

● package 18MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

flake8_annotations

✓ (Run flake8 command)

flake8-annotations is a Flake8 plugin and is automatically detected and run by Flake8 when installed. There are no direct Python imports for its functionality.

Install flake8 and flake8-annotations. Create a Python file (e.g., `example.py`) with functions, some with and some without type annotations. Run `flake8 example.py` from your terminal to see the reported issues regarding missing annotations.

import os def my_function(arg1, arg2): # This function is missing type annotations return arg1 + arg2 def another_function(value: int) -> str: return str(value) # To run flake8, save this as example.py and execute: # flake8 example.py # You should see errors like ANN001, ANN201 for my_function.

flake8 --version

Debug

Known issues

breakingVersion 3.0.0 introduced significant breaking changes, requiring Python >=3.8.1 and Flake8 >=5.0. Projects using older Python or Flake8 versions must upgrade their environment or pin flake8-annotations to a version <3.0.0.

fix

Ensure your project's `requires-python` is >=3.8.1 and `flake8` dependency is >=5.0. Version 3.2.0 further raised the Python requirement to >=3.10.

affects: >=3.0.0

breakingAs of v3.0.0, support for PEP 484-style type comments (e.g., `# type: (str) -> None`) was removed. Instead, the new `ANN402` warning code (disabled by default) flags the *presence* of these now-unsupported type comments.

fix

Migrate all type comments to PEP 526-style variable annotations (e.g., `def func(arg: str) -> None:`). Enable `ANN402` to detect lingering type comments: `flake8 --extend-select ANN402`.

affects: >=3.0.0

gotcha`ANN4xx` error codes (e.g., `ANN401` for `typing.Any`, `ANN402` for type comments) are considered 'opinionated warnings' and are disabled by default.

fix

To enable these warnings, use `flake8 --extend-select ANN401,ANN402` (or similar) in your command line or `extend-select = ANN401,ANN402` in your `pyproject.toml`, `setup.cfg`, or `.flake8` configuration file.

affects: >=2.8.0

gotchaThe `ANN401` warning for `typing.Any` can be overly strict, especially for `*args: Any` and `**kwargs: Any`.

fix

Use the `--allow-star-arg-any` flag (added in v2.9.0) to suppress `ANN401` specifically for `*args` and `**kwargs` annotations if this is an acceptable pattern in your codebase.

affects: >=2.8.0

gotchaBy default, `flake8-annotations` does not respect `# type: ignore` comments.

fix

Enable the `--respect-type-ignore` flag (available since v3.1.0) to suppress linting errors for functions or modules annotated with `# type: ignore`. Module-level `# mypy: ignore-errors` or `# type: ignore` on the first line is also supported.

affects: <3.1.0

Upgrade

Version history

3.2.0latest on PyPI · released Oct 9, 2025

Audit

Dependencies

flake8requiredflake8-annotations is a plugin for Flake8 and requires Flake8 to run.

pythonrequiredMinimum Python version required by the package.

Agent activity

9 hits · last 30 days

node

Resources

githubhttps://github.com/sco1/flake8-annotations ↗

packagehttps://pypi.org/project/flake8-annotations/ ↗

docshttps://github.com/sco1/flake8-annotations/blob/main/README.md ↗

changeloghttps://github.com/sco1/flake8-annotations/blob/main/CHANGELOG.md ↗