check-imports

Checks import from declarations, import and require calls then updates or removes package.json dependencies (if update option described below is set to true, otherwise you only get informed) from package.json files. Works great with single-package modules as well as with big projects with multiple package.json files (for example if you have a monorepo powered by lerna).

TL;DR

Install: npm i -D check-imports and use: npx check-imports.

How it works

1. The library gets all .js, .jsx, .ts files by a given path;
2. Builds their AST trees via @babel/parser;
3. Retrieves import paths from import from, require(), import();
4. Runs some filters and mappings:
   1. Ignore relative paths;
   2. Ignore built-in NodeJS modules such as path, fs, child_process etc;
   3. Retrieve module names (lodash/pick becomes lodash);
   4. Retrieve module names from scoped packages (@scope/module/foo/bar becomes @scope/module);
   5. Get rid of Webpack syntax (foo!bar!baz?quux=bat&xyzzy=plugh becomes baz);
5. Finds a "parent" (a closest) package.json file;
6. Compares its contents with the retrieved list of imports and if update option is set to true the script updates it.
   1. If ignore option is provided then "dependencies" aren't going to be updated with a given dependency or multiple dependencies;
   2. If a dependency already exists either at "dependencies", "optionalDependencies" or "peerDependencies" then "dependencies" aren't going to be updated and a dependency version remains the same;
   3. If neither of things above is happened then a dependency of a latest version retrieved from NPM registry is going to be added to "dependencies".

Note that after an update you still need to run npm install manually.

A bonus: imports can be ignored directly in code via check-imports-ignore-line comment

require('lodash'); // check-imports-ignore-line

CLI

The tool can be run via npx check-imports.

Options

• -u, --update - update parent package.json files.
• -e, --throw-error - exit process with code 1 in case if there are redundant or missing dependencies (good for CI).
• -d, --directory-path <value> - a directory where JavaScript/TypeScript/JSX files are located.
• --ignore-path <items> - a glob pattern (or coma-delimited patterns) to ignore processed files (--ignore-path "**/foo/*.js").
• -n, --ignore-imports <items> - a comma-delimited list of dependencies that don't need to appear at "dependencies".

API

const { checkImports } = require('check-imports');

The API includes a bit wider set of options. It allows to map dependencies to check if a dependency needs to be ignored or get a wanted version. It also allows to set a list of babel plugin passed to babelParser in case if you need to make the tool work with flow syntax for example.

const results = await checkImports(options);

Options

• update = false - either update package.json files or not.
• throwError = false - throw an error in case if there are redundant or missing dependencies
• log = false - print CLI output
• directoryPath = process.cwd() - a directory where JavaScript/TypeScript/JSX files are located.
• ignorePath = [] - a glob pattern or an array of patterns to ignore processed files.
• babelPlugins = require('./defaultBabelPlugins') - a list of parser plugins described there.
• processManually = null - a function which is run agains every found import. You may want to define it in case if you want to ignore some dependencies or set a wanted version. It should return either of the following values:
  • true - process a dependency a regular way.
  • false - ignore a dependency.
  • An object with optional keys version and type. version field makes possible to forcibly define a dependency version. type field defines a key at package.json where a dependency needs to be stored ("optionalDependencies", "peerDependencies" or any custom). By default its value is "dependencies".

const results = await checkImports({
  directoryPath: path.resolve(__dirname, 'foo'),
  ignorePath: ['**/ignored.*'],
  processManually: (dependency) => {
    if (dependency === 'react') {
      // forcibly set version to 1.1.1 and add it to peerDependencies
      return {
        version: '1.1.1',
        type: 'peerDependencies',
      };
    }
    if (dependency === 'react-redux') {
      // add it to customDependencies
      return {
        type: 'customDependencies',
      };
    }
    if (dependency === 'moment') {
      // forcibly set version to ^999.999.999
      return {
        version: '^999.999.999',
      };
    }
    if (dependency === 'redux') {
      // ignore the dependency
      return false;
    }

    // else process regularly
    return true;
  },
  update: true,
});