Detect if code is running as an npm script but not a yarn script.
npm install is-npm-not-yarn> Detect if code is running as an npm script but not a yarn script.
Note: Use with >= yarn@1 requires >= is-npm-not-yarn@2.
js
var isNpmNotYarn = require('is-npm-not-yarn')
console.log(isNpmNotYarn) // true or false
`$3
is-npm-not-yarn
exit code of if is npm and not yarn, else 1`