src/State.js
function isEmpty(o) {
  for (var key in o) {
    if (o.hasOwnProperty(key)) {
      return false;
    }
  }
  return Object.getOwnPropertySymbols(o).length === 0;
}
function isEmpty(o) {
  for (var key in o) {
    if (o.hasOwnProperty(key)) {
      return false;
    }
  }
  return Object.getOwnPropertySymbols(o).length === 0;
}
function isEmpty ( o ) { for ( var key in o ) { if ( o . hasOwnProperty ( key ) ) { return false ; } } return Object . getOwnPropertySymbols ( o ) . length === 0 ; }
Return true if o is an empty object.
Return true if o is an empty object .