Depcheck

depcheck looks through the files in your project to either:

• With depcheck: find packages that are listed in package.json that are no longer used
• With localcheck: find files that are not referenced by any other Javascript file (e.g., orphaned in a refactor)

Usage

To use depcheck or localcheck, you need to create a depcheck.json file, which has the following format:

• files: array of globs whose require/import statements you want to check

• filesToCheck: the package.json or other files you'd like to check. This can either be an array of files, or a hash in the format of:

  {
    "vendorPackages.json": "fullPath",
    "packages.json": "packages",
  }

  packages means we want to make sure the package itself is defined (e.g., react-bootstrap), while fullPath means we want the full required string to be present (react-bootstrap/lib/Modal).

  For files named package.json, it'll look in dependencies and devDependencies. For all other files, it will assume the file is an array of packages, and just look in the top-level array.

• ignorePackages is a list of packages that you'd like to be ignored even if it seems like they're unused. These are most often used for linters, Babel transforms, and other implicit dependencies.

Once you have a depcheck.json, simply run it using:

depcheck depcheck.json

Sample depcheck.json

{
  "files": [
    "{gulpfile.js,build/**/*.js}",
    "client/{assets,js,templates}/**/*.{scss,js,coffee}",
    "server/{{app,scripts}/**/*.js,app.js}",
    "test/**/*.js"
  ],
  "filesToCheck": ["package.json"],
  "ignorePackages": [
    "babel-core",
    "babel-eslint",
    "babel-loader",
    "babel-preset-react",
    "babel-preset-es2015",
    "babel-plugin-transform-class-properties",
    "bluebird",
    "eslint",
    "eslint-config-airbnb",
    "eslint-config-airbnb-base",
    "eslint-plugin-flowtype",
    "eslint-plugin-import",
    "eslint-plugin-jsx-a11y",
    "eslint-plugin-react",
    "flow-bin",
    "json-loader",
    "minifyify",
    "history",
    "mysql",
    "mocha"
  ]
}