Compares two TypeScript / ES6 maps

compareTwoMaps.ts

function areMapsEqual(left: Map<number, string []>, right: Map<number, string []>): boolean  {
  if (left.size !== right.size) { return false }
  const leftKeys = Array.from(left.keys()).sort()
  const rightKeys = Array.from(right.keys()).sort()
  if ( leftKeys !== rightKeys ) { return false }

  for ( const key of leftKeys ) {
   const leftValues = left.get(key) || []
   const rightValues = right.get(key) || []
   if ( leftValues.sort() !== rightValues.sort()) { return false }
  }
  return true
}