esnext.set.map.js 1.1 KB
'use strict';
var $ = require('../internals/export');
var getBuiltIn = require('../internals/get-built-in');
var bind = require('../internals/function-bind-context');
var call = require('../internals/function-call');
var aCallable = require('../internals/a-callable');
var anObject = require('../internals/an-object');
var speciesConstructor = require('../internals/species-constructor');
var getSetIterator = require('../internals/get-set-iterator');
var iterate = require('../internals/iterate');

// `Set.prototype.map` method
// https://github.com/tc39/proposal-collection-methods
$({ target: 'Set', proto: true, real: true, forced: true }, {
  map: function map(callbackfn /* , thisArg */) {
    var set = anObject(this);
    var iterator = getSetIterator(set);
    var boundFunction = bind(callbackfn, arguments.length > 1 ? arguments[1] : undefined);
    var newSet = new (speciesConstructor(set, getBuiltIn('Set')))();
    var adder = aCallable(newSet.add);
    iterate(iterator, function (value) {
      call(adder, newSet, boundFunction(value, value, set));
    }, { IS_ITERATOR: true });
    return newSet;
  }
});