Get all states in a Google Maps Directions Result

getRouteStates.js

// route is a DirectionsRoute interface
// see: https://developers.google.com/maps/documentation/javascript/reference/directions#DirectionsRoute

function getRouteStates(route) {
  let states = [],
    routeLeg = route.legs[0] // first leg of the route is the starting point

  states.push(
    routeLeg.start_address
      .split(',') // split on commas
      .reverse()[1] //reverse and get the second to last item, USA is always first item
      .replace(/\d/g, '') //replace any digits (ie zipcode)
      .trim() //remove spaces
  )
  
  routeLeg.steps.filter(step => step.instructions.search(/Entering|Passing through/) !== -1)
    .map(step =>
      step.instructions
        .match(/(Entering|Passing through)\s([a-zA-Z\s]*)((,?)\s([A-Za-z\s]*))?/gm)
        .map(phrase =>
          phrase.split('Entering')
            .pop()
            .split('Passing through')
            .pop()
            .split(',')
            .forEach(state => states.push(state.trim()))
        )
    )
  
  return states
}