Code Quality

Linting

ESLint

ESLint checks TypeScript and JavaScript files using TypeScript-aware rules and Playwright-specific rules (e.g., no standalone expect, proper await on assertions).

Command	Description
pnpm lint	Run ESLint
pnpm lint:fix	Run ESLint with auto-fix

Configuration: eslint.config.js

Markdownlint

Markdownlint checks markdown files in docs/ and the project root. Several rules are relaxed for VitePress compatibility (long lines, inline HTML, duplicate headings).

Command	Description
pnpm lint:md	Lint markdown files
pnpm lint:md:fix	Lint markdown files, auto-fix

Configuration: .markdownlint-cli2.jsonc

Formatting

Prettier handles all code formatting. It runs on TypeScript, JavaScript, JSON, YAML, CSS, and markdown files.

Command	Description
pnpm format	Format all files with Prettier
pnpm format:check	Check formatting without changing

Configuration: .prettierrc

Git Hooks

A pre-commit hook runs linting and formatting checks automatically on every commit. Three packages work together to make this happen:

git commit
  └─ .git/hooks/pre-commit          (created by simple-git-hooks)
       └─ pnpm lint-staged           (runs lint-staged CLI)
            └─ lint-staged.config.mjs (defines which tools run on which files)

How It Works

1. simple-git-hooks reads the "simple-git-hooks" section in package.json and writes a shell script to .git/hooks/pre-commit. The script calls pnpm lint-staged.

2. lint-staged picks up lint-staged.config.mjs by naming convention. It runs the configured tools only on staged files, so commits stay fast regardless of project size.

3. lint-staged.config.mjs defines the rules:

   File Pattern	Tools
   *.{ts,js,mjs,cjs}	ESLint, Prettier
   *.{json,yml,yaml,css}	Prettier
   *.md (excl. .claude/)	markdownlint
   .prettierrc	Prettier

Regenerating Hooks

Changes to the "simple-git-hooks" config in package.json are not picked up automatically. After modifying the hook configuration, run:

npx simple-git-hooks

This regenerates the .git/hooks/pre-commit script from the updated config.

First-Time Setup

After cloning the repository, the git hook doesn't exist yet. Running pnpm install does not set it up automatically. To install the hook:

npx simple-git-hooks

Config Files

File	Purpose
eslint.config.js	ESLint rules (TypeScript + Playwright)
.prettierrc	Prettier formatting options
.prettierignore	Files excluded from Prettier
.markdownlint-cli2.jsonc	Markdownlint rules and file globs
lint-staged.config.mjs	Pre-commit checks per file type
package.json (simple-git-hooks)	Maps git hooks to commands