depcheck

What is depcheck?

depcheck is a tool that helps you to find unused dependencies in your project. It scans your project files and identifies which dependencies are not being used, which can help you to clean up your package.json file and reduce the size of your project.

What are depcheck's main functionalities?

Check for unused dependencies

This feature allows you to check for unused dependencies in your project. You can specify options to ignore certain directories or dependencies that match specific patterns.

const depcheck = require('depcheck');

const options = {
  ignoreDirs: [
    'sandbox',
    'dist',
    'bower_components'
  ],
  ignoreMatches: [
    'grunt-*'
  ]
};

depcheck('/path/to/your/project', options, (unused) => {
  console.log(unused.dependencies); // an array containing the unused dependencies
  console.log(unused.devDependencies); // an array containing the unused devDependencies
});

Check for missing dependencies

This feature allows you to check for dependencies that are used in your project but are not listed in your package.json file.

const depcheck = require('depcheck');

depcheck('/path/to/your/project', {}, (unused) => {
  console.log(unused.missing); // a lookup containing the dependencies missing in package.json but used in the code
});

Check for invalid files

This feature allows you to identify files in your project that could not be parsed, which might indicate issues with those files.

const depcheck = require('depcheck');

depcheck('/path/to/your/project', {}, (unused) => {
  console.log(unused.invalidFiles); // a lookup containing the files that could not be parsed
});

Other packages similar to depcheck

npm-check

npm-check is a similar tool that checks for outdated, incorrect, and unused dependencies. It provides a more interactive experience compared to depcheck, allowing you to update and uninstall packages directly from the command line.

dependency-check

dependency-check is another tool that checks for missing or unused dependencies. It is more focused on ensuring that all dependencies are correctly listed in your package.json file, rather than identifying unused dependencies.

madge

madge is a tool that provides a visual representation of your project's dependency graph. While it does not specifically focus on unused dependencies, it can help you understand the structure of your project and identify potential issues.

README

depcheck

Keeping track of your dependencies is not an easy task, especially if you have a big project. Are you sure you are using all of the dependencies you define in your package.json file? One way to find out is to look at all your files and check which modules you are using, but that's too time consuming. Or maybe you can do a grep on all the files of your project, and then some grep -v to remove the junk. But that's a hassle too.

And that is why depcheck exists - it's a nifty little tool that looks at your project files and scans your code in order to find any unused dependencies.

Build Status

Features

• Support ES5, ES6, ES7, JSX and CoffeeScript syntax.
• Detect using ESLint configuration preset, parser and plugins.
• Detect using Webpack loaders.
• Detect Babel presets and plugins.
• Recognize the packages used in grunt.tasks.loadNpmTasks call.
• Smart to identify the binary package used in commands.

Installation

npm install depcheck -g

Usage

depcheck [directory] [arguments]

The directory argument is the root directory of your project (where the package.json file is). It will be the current directory when not specified.

All the arguments are optional:

--dev=[true|false]: A flag indicates if depcheck looks at devDependencies. By default, it is true. It means, depcheck looks at both dependencies and devDependencies.

--ignore-bin-package=[true|false]: A flag indicates if depcheck ignores the packages containing bin entry. The default value is true.

--json: Output results to JSON. When not specified, depcheck outputs in human friendly format.

--ignores: A comma separated array containing package names to ignore. It can be glob expressions. Example, --ignores=eslint,babel.

--ignores-dirs: A comma separated array containing directory names to ignore. Example, --ignore-dirs=dist,coverage.

--help: Show the help message.

--parsers, --detectors and --specials: These arguments are for advanced usage. They provide an easy way to customize the file parser and dependency detection. Check the pluggable design document for more information.

API

Want to call depcheck from code? See the example:

var path = require('path');
var depcheck = require('depcheck');

var options = {
  withoutDev: false, // check against devDependencies
  ignoreBinPackage: false, // ignore the packages with bin entry
  ignoreDirs: [ // folder with these names will be ignored
    'sandbox',
    'dist',
    'bower_components'
  ],
  ignoreMatches: [ // ignore dependencies that matches these globs
    'grunt-*'
  ],
  parsers: { // the target parsers
    '*.js': depcheck.parser.es6,
    '*.jsx': depcheck.parser.jsx
  },
  detectors: [ // the target detectors
    depcheck.detector.requireCallExpression,
    depcheck.detector.importDeclaration
  ],
  specials: [ // the target special parsers
    depcheck.special.eslint,
    depcheck.special.webpack
  ]
};

depcheck('/path/to/your/project', options, function(unused) {
  console.log(unused.dependencies); // an array containing the unused dependencies
  console.log(unused.devDependencies); // an array containing the unused devDependencies
  console.log(unused.invalidFiles); // files that cannot access or parse
  console.log(unused.invalidDirs); // directories that cannot access
});

License

MIT License.

Changelog

0.5.11 (2015-12-02)

Full Changelog

Closed issues:

• Ignore doc folder in NPM deployment. #77
• Output error call stack in JSON output. #75
• Add --version parameter. #74
• request support: -h/--help arguments #73
• wrong repo link in published module #57