'use strict';
|
var $ = require('../internals/export');
|
var getBuiltIn = require('../internals/get-built-in');
|
var bind = require('../internals/function-bind-context');
|
var uncurryThis = require('../internals/function-uncurry-this');
|
var IndexedObject = require('../internals/indexed-object');
|
var toObject = require('../internals/to-object');
|
var lengthOfArrayLike = require('../internals/length-of-array-like');
|
var arrayMethodIsStrict = require('../internals/array-method-is-strict');
|
var addToUnscopables = require('../internals/add-to-unscopables');
|
|
var Map = getBuiltIn('Map');
|
var MapPrototype = Map.prototype;
|
var mapGet = uncurryThis(MapPrototype.get);
|
var mapHas = uncurryThis(MapPrototype.has);
|
var mapSet = uncurryThis(MapPrototype.set);
|
var push = uncurryThis([].push);
|
|
// `Array.prototype.groupByToMap` method
|
// https://github.com/tc39/proposal-array-grouping
|
// https://bugs.webkit.org/show_bug.cgi?id=236541
|
$({ target: 'Array', proto: true, forced: !arrayMethodIsStrict('groupByToMap') }, {
|
groupByToMap: function groupByToMap(callbackfn /* , thisArg */) {
|
var O = toObject(this);
|
var self = IndexedObject(O);
|
var boundFunction = bind(callbackfn, arguments.length > 1 ? arguments[1] : undefined);
|
var map = new Map();
|
var length = lengthOfArrayLike(self);
|
var index = 0;
|
var key, value;
|
for (;length > index; index++) {
|
value = self[index];
|
key = boundFunction(value, index, O);
|
if (mapHas(map, key)) push(mapGet(map, key), value);
|
else mapSet(map, key, [value]);
|
} return map;
|
}
|
});
|
|
addToUnscopables('groupByToMap');
|
