Pycheck

An opinionated code quality checker for Python. Pycheck runs some code checking tools, shows the problems and generates a note for the code. Checks:

• Formating with Black
• Codestyle with Flake8
• Typing with Pyright

Packages

Version	Name	Description
	@pycheck/cli	The terminal client
	@pycheck/ui	The in browser user interface
	@pycheck/types	The Typescript shared data structures

Terminal client

Install

Requirements: to have the base tools installed: Black, Flake8 and Pyright:

# install the python packages
pip install black flake8 pyright

Install Pycheck:

yarn global add @pycheck/cli
# or 
npm install -g @pycheck/cli

This way you can run pycheck in any project directory

Run

To run Pycheck vs any python directory:

pycheck /my/python/dir

With no parameters it will run in the current directory, looking for python code

Available options:

• -s: display suggestions about how to resolve the problems
• -v: will display more info (the list of files to format)
• --debug: print the commands
• --disable-typing: an option to not run the Pyright checks, just Flake and Black

Presets

Some presets options are available for the level of checks:

• --untyped: to run with permissive type checking
• --django: to run for a Django project

Example with options:

pycheck -s --untyped

It is possible to declare a preset in the setup.cfg file in your project instead of using a command line flag:

[pycheck]
preset = django

Ignore options

Pyright

To ignore files in Pyright declare the list in a pyrightconfig.json file at the root of your project:

{
  "exclude": [
    "build",
    "dist"
  ]
}

Flake

To ignore files in Flake8 declare a section in your setup.cfg file:

[flake8]
max-line-length = 88
exclude = .git,.venv,build,__pycache__,*/migrations/*

Black

By default the exclude list for Black will use the one of Flake if declared. To disable this behavior, in setup.cfg:

[pycheck]
black-ignore = disabled

To provide a custom regex ignore string to Black:

[pycheck]
black-ignore = '\\.git|\\.venv|build|__pycache__|\\*/migrations/\\*'

Example output:

Using preset untyped
Checking formatting with Black ...
Checking codestyle with Flake8 ...
Checking typing with Pyright ...

-----------------------
☢️  Found some problems:
-----------------------

🔴 (3) sandbox/settings/tests.py
  - 1: F403 'from sandbox.settings.base import *' used; unable to detect undefined names
  - 14: F405 'join' may be undefined, or defined from star imports: sandbox.settings.base
  - 19: F405 'VAR_PATH' may be undefined, or defined from star imports: sandbox.settings.base
🔴 (2) docs/conf.py
  - 1: E402 module level import not at top of file
  - 1: E402 module level import not at top of file
🔴 (5) docs/django_settings.py
  - 1: F401 'os.listdir' imported but unused
  - 1: F401 'os.path.normpath' imported but unused
  - 1: E402 module level import not at top of file
  - 1: F403 'from demospa.settings import *' used; unable to detect undefined names
  - 1: F401 'demospa.settings.*' imported but unused
🔴 (1) sandbox/settings/demo.py
  - 1: F403 'from sandbox.settings.base import *' used; unable to detect undefined names
🔵 (4) sandbox/settings/tests.py
  - 11: "join" is not defined (reportUndefinedVariable)
  - 11: "VAR_PATH" is not defined (reportUndefinedVariable)
  - 18: "join" is not defined (reportUndefinedVariable)
  - 18: "VAR_PATH" is not defined (reportUndefinedVariable)
🔵 (2) sandbox/settings/demo.py
  - 12: "join" is not defined (reportUndefinedVariable)
  - 12: "VAR_PATH" is not defined (reportUndefinedVariable)
⚫ 25 files could be formated
Code score: 68/100
  - Formating: 0/10
  - Codestyle: 44/60
  - Typing: 24/30

In browser user interface

Install

yarn global add @pycheck/ui
# or 
npm install -g @pycheck/ui

Run

cd my/python/project
pycheckui

Open localhost:5143

Database

By default it will create a .pycheck.db file in the running directory (a Sqlite database to store history). To change this behavior you can provide a database path:

# absolute path
pycheckui --db=/path/to/pycheck.db
# relative path: relative to the running directory
pycheckui --db=path/to/pycheck.db

It is possible to use only one database for all projects with this flag

Editor

Configure your editor command to open some files directly from the ui. Use the settings button in the bottom left corner:

More Screenshots

History

Package versions

Development

To run in development mode: run the backend in a Python project:

cd a/python/project
ts-node --transpile-only ~/path/to/pycheck/packages/ui/server/src/index.ts

Run the frontend: in the pycheck directory

cd path/to/pycheck
cd packages/ui/client
yarn dev

Open localhost:5173 to get frontend. It will autoreload when the frontend code changes