prettierrc

Prettierrc refers to the configuration files used by Prettier, a widely adopted code formatter that enforces a consistent style across a project. The prettierrc file stores preferences that influence how source code is formatted, including line length, quote style, and spacing. By configuring Prettier, teams can ensure uniform formatting regardless of individual editors or IDEs.

A configuration can take several forms. Common names include .prettierrc, .prettierrc.json, .prettierrc.yaml or .prettierrc.yml, .prettierrc.js, or prettier.config.js. A project may also place a "prettier" key in package.json. Prettier supports JSON, YAML, and JavaScript/JavaScript-like module exports for configuration. It will locate the configuration by walking up from the file being formatted, stopping at the project root or a global config.

The configuration is a JSON-like object of options. Widely used settings include printWidth (line length), tabWidth, useTabs, semi, singleQuote, trailingComma, endOfLine, bracketSpacing, jsxBracketSameLine, and arrowParens. Other options cover quoteProps, proseWrap, requirePragma, and insertPragma. An overrides array lets you apply different rules to specific file patterns, and an ignorePath or .prettierignore file can exclude files from formatting.

If no prettierrc is found, Prettier falls back to its default options. Editor integrations, build scripts, and CI pipelines can read these configuration files to ensure consistent formatting across development environments.