17ba366bb8
A helpful utility which converts iterables and array-like objects into Arrays https://people.mozilla.org/~jorendorff/es6-draft.html#sec-array.from LOG=Y BUG=v8:3336 R=arv@chromium.org, rossberg@chromium.org Review URL: https://codereview.chromium.org/363833006 Cr-Commit-Position: refs/heads/master@{#25785}
124 lines
4.2 KiB
JavaScript
124 lines
4.2 KiB
JavaScript
// Copyright 2014 the V8 project authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
// Flags: --harmony-arrays --harmony-generators
|
|
(function() {
|
|
|
|
assertEquals(1, Array.from.length);
|
|
|
|
function assertArrayLikeEquals(value, expected, type) {
|
|
assertInstanceof(value, type);
|
|
assertEquals(expected.length, value.length);
|
|
for (var i=0; i<value.length; ++i) {
|
|
assertEquals(expected[i], value[i]);
|
|
}
|
|
}
|
|
|
|
// Assert that constructor is called with "length" for array-like objects
|
|
var myCollectionCalled = false;
|
|
function MyCollection(length) {
|
|
myCollectionCalled = true;
|
|
assertEquals(1, arguments.length);
|
|
assertEquals(5, length);
|
|
}
|
|
|
|
Array.from.call(MyCollection, {length: 5});
|
|
assertTrue(myCollectionCalled);
|
|
|
|
// Assert that calling mapfn with / without thisArg in sloppy and strict modes
|
|
// works as expected.
|
|
var global = this;
|
|
function non_strict(){ assertEquals(global, this); }
|
|
function strict(){ "use strict"; assertEquals(void 0, this); }
|
|
function strict_null(){ "use strict"; assertEquals(null, this); }
|
|
Array.from([1], non_strict);
|
|
Array.from([1], non_strict, void 0);
|
|
Array.from([1], non_strict, null);
|
|
Array.from([1], strict);
|
|
Array.from([1], strict, void 0);
|
|
Array.from([1], strict_null, null);
|
|
|
|
function testArrayFrom(thisArg, constructor) {
|
|
assertArrayLikeEquals(Array.from.call(thisArg, [], undefined), [],
|
|
constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, NaN), [], constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, Infinity), [], constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, 10000000), [], constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, 'test'), ['t', 'e', 's', 't'],
|
|
constructor);
|
|
|
|
assertArrayLikeEquals(Array.from.call(thisArg,
|
|
{ length: 1, '0': { 'foo': 'bar' } }), [{'foo': 'bar'}], constructor);
|
|
|
|
assertArrayLikeEquals(Array.from.call(thisArg,
|
|
{ length: -1, '0': { 'foo': 'bar' } }), [], constructor);
|
|
|
|
assertArrayLikeEquals(Array.from.call(thisArg,
|
|
[ 'foo', 'bar', 'baz' ]), ['foo', 'bar', 'baz'], constructor);
|
|
|
|
var kSet = new Set(['foo', 'bar', 'baz']);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, kSet), ['foo', 'bar', 'baz'],
|
|
constructor);
|
|
|
|
var kMap = new Map(['foo', 'bar', 'baz'].entries());
|
|
assertArrayLikeEquals(Array.from.call(thisArg, kMap),
|
|
[[0, 'foo'], [1, 'bar'], [2, 'baz']], constructor);
|
|
|
|
|
|
function* generator() {
|
|
yield 'a';
|
|
yield 'b';
|
|
yield 'c';
|
|
}
|
|
|
|
assertArrayLikeEquals(Array.from.call(thisArg, generator()),
|
|
['a', 'b', 'c'], constructor);
|
|
|
|
// Mozilla:
|
|
// Array.from on a string handles surrogate pairs correctly.
|
|
var gclef = "\uD834\uDD1E"; // U+1D11E MUSICAL SYMBOL G CLEF
|
|
assertArrayLikeEquals(Array.from.call(thisArg, gclef), [gclef], constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, gclef + " G"),
|
|
[gclef, " ", "G"], constructor);
|
|
|
|
assertArrayLikeEquals(Array.from.call(thisArg, 'test', function(x) {
|
|
return this.filter(x);
|
|
}, {
|
|
filter: function(x) { return x.toUpperCase(); }
|
|
}), ['T', 'E', 'S', 'T'], constructor);
|
|
assertArrayLikeEquals(Array.from.call(thisArg, 'test', function(x) {
|
|
return x.toUpperCase();
|
|
}), ['T', 'E', 'S', 'T'], constructor);
|
|
|
|
this.thisArg = thisArg;
|
|
assertThrows('Array.from.call(thisArg, null)', TypeError);
|
|
assertThrows('Array.from.call(thisArg, undefined)', TypeError);
|
|
assertThrows('Array.from.call(thisArg, [], null)', TypeError);
|
|
assertThrows('Array.from.call(thisArg, [], "noncallable")', TypeError);
|
|
|
|
this.nullIterator = {};
|
|
nullIterator[Symbol.iterator] = null;
|
|
assertThrows('Array.from.call(thisArg, nullIterator)', TypeError);
|
|
|
|
this.nonObjIterator = {};
|
|
nonObjIterator[Symbol.iterator] = function() { return "nonObject"; };
|
|
assertThrows('Array.from.call(thisArg, nonObjIterator)', TypeError);
|
|
|
|
assertThrows('Array.from.call(thisArg, [], null)', TypeError);
|
|
}
|
|
|
|
function Other() {}
|
|
|
|
var boundFn = (function() {}).bind(Array, 27);
|
|
|
|
testArrayFrom(Array, Array);
|
|
testArrayFrom(null, Array);
|
|
testArrayFrom({}, Array);
|
|
testArrayFrom(Object, Object);
|
|
testArrayFrom(Other, Other);
|
|
testArrayFrom(Math.cos, Array);
|
|
testArrayFrom(boundFn, Array);
|
|
|
|
})();
|