Recursive areEquivalents function.

areEquivalents.js

function areEquivalents (a, b) {
  if (a && b && typeof a === 'object' && typeof a === typeof b && a.length === b.length) {
    for (var prop in a) {
      if (a.hasOwnProperty(prop) && !areEquivalents(a[prop], b[prop])) {
        return false
      }
    }
    for (var prop in b) {
      if (b.hasOwnProperty(prop) && !areEquivalents(b[prop], a[prop])) {
        return false
      }
    }
  } else if (Number.isNaN(a) && Number.isNaN(b)) {
    return true
  } else if (a !== b) {
    return false
  }
  
  return true
}