has-yarn

Check if a project is using Yarn

Useful for tools that needs to know whether to use yarn or npm to install dependencies.

It checks for a yarn.lock file in the given directory or any of its parent directories (useful for Yarn workspaces).

Install

npm install has-yarn

Usage

.
├── foo
│   └── package.json
└── bar
    ├── package.json
    └── yarn.lock

import hasYarn from 'has-yarn';

hasYarn('foo');
//=> false

hasYarn('bar');
//=> true

// In a Yarn workspace
hasYarn('bar/packages/some-package');
//=> true

API

hasYarn(cwd?)

Returns a boolean of whether the project uses Yarn.

cwd

Type: string
Default: process.cwd()

The directory to check. The search also walks up parent directories until the filesystem root.

Related

• has-yarn-cli - CLI for this package