Testing & Code Quality

Prettier & Formatting

Prettier parses source code and reprints it in a consistent style. Its main value is not that the style is perfect; it is that formatting stops being a human argument.

Prettier is intentionally opinionated
Formatter and linter have different jobs
Format checks belong in CI
Formatting is not code quality
Generated files may need exclusions

Formatting scripts

{
  "scripts": {
    "format": "prettier --write .",
    "format:check": "prettier --check ."
  }
}

One command to fix, one command for CI.

Tool responsibilities
Tool	Primary job	Avoid
Prettier	Formatting/layout	Semantic code rules
ESLint	Code quality and correctness rules	Competing formatting rules
TypeScript	Static type checking	Style enforcement
Editor integration	Format on save	Different team behavior per machine