Code Quality & Linting

​

Overview

• Ruff - Python linting and formatting
• ESLint - JavaScript linting
• Stylelint - SCSS linting

​

Python: Ruff

​

Run Linting

make lint

1. Code linting: ruff check .
2. Format checking: ruff format --check .

​

Check Code Only

ruff check .

​

Check Formatting

ruff format --check .

​

Auto-Fix Issues

ruff check --fix .

​

Auto-Format Code

ruff format .

​

Ruff Configuration

line-length = 120
target-version = "py313"

extend-exclude = [
    "migrations/versions/",
    "__pycache__",
    "cache",
    "migrations",
    "build",
    "sample_cap_xml_documents.py",
]

​

Enabled Rules

• E, W - pycodestyle errors and warnings
• F - pyflakes
• I - isort (import sorting)
• B - flake8-bugbear
• C90 - mccabe cyclomatic complexity
• G - flake8-logging-format
• T20 - flake8-print (no print statements)
• UP - pyupgrade (modern Python syntax)
• C4 - flake8-comprehensions
• ISC - flake8-implicit-str-concat
• RSE - flake8-raise
• PIE - flake8-pie
• N804 - class method naming
• RUF100 - unused noqa directives

​

JavaScript: ESLint

​

Run ESLint

npm run lint:js

​

Configuration

• Semicolons required
• Warnings for unused variables and undefined variables
• Based on ESLint recommended configuration

​

SCSS: Stylelint

​

Run Stylelint

npm run lint:scss

npm test

​

Configuration

export default {
  extends: [
    "stylelint-config-standard-scss",
    "stylelint-config-gds/scss"
  ],
  // Custom rule overrides
}

• stylelint-config-standard-scss - Standard SCSS rules
• stylelint-config-gds/scss - GOV.UK Design System SCSS rules

​

CI Integration

• Before tests via make test
• In CI/CD pipelines
• Should be run before committing code

​

Pre-commit Workflow

# Auto-fix Python issues
ruff check --fix .
ruff format .

# Check JavaScript and SCSS
npm run lint:js
npm run lint:scss

# Run tests (includes linting)
make test

​

NPM Audit

make npm-audit

npm run audit