force-npm

#force-npm

Force users to use npm instead of yarn.

If run from yarn instead of npm, the process will exit with error code 1 and print an error message.

Note: this will not work if used with yarn add --dev --ignore-scripts. Note: This is fork of use-yarn

Install

npm install --save-dev force-npm 
# or
yarn add --dev force-npm 

Use

CLI

For example, in your package.json:

{
  "scripts": {
     "preinstall": "force-npm || ( npm install --save-dev --no-scripts --no-save force-npm && force-npm )"
  }
}

Or if you're on npm >=5 or have npx:

{
  "scripts": {
     "preinstall": "npx force-npm"
  }
}

You may provide a custom message via the -m flag:

{
  "scripts": {
     "preinstall": "npx force-npm -m 'Please use npm!'"
  }
}

Or, you may also provide a custom message read from a file via the -f flag:

{
  "scripts": {
     "preinstall": "npx force-npm -f path/to/customMessage.txt"
  }
}

You may disable force-npm by setting the DISABLE_FORCE_NPM environment variable to true:

{
  "scripts": {
     "preinstall": "DISABLE_FORCE_NPM=true npx force-npm"
  }
}

API

var forceNpm = require('force-npm')

forceNpm()

// or a custom message
forceNpm('You idiot!')