myDerps.js

const shell = require('node-powershell');
 
let ps = new shell({
  executionPolicy: 'Bypass',
  noProfile: true
});

function psPing(thisIP) {
  ps.addCommand('Test-Connection -quiet -count 1 ' + thisIP)
  return ps.invoke()
   .catch(err => {
     console.warn(err);
     ps.dispose();
   });
}

psPing("192.168.0.1").then((result) => {
 if (result === 'true') {
   // do stuff
   // return; <-- early return
 }
 // do stuff here, which is if it's not 'true'
})