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// 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.
// Based on Mozilla Array.of() tests at http://dxr.mozilla.org/mozilla-central/source/js/src/jit-test/tests/collections
// Flags: --harmony-arrays
// Array.of makes real arrays.
function check(a) {
assertEquals(Object.getPrototypeOf(a), Array.prototype);
assertEquals(Array.isArray(a), true);
a[9] = 9;
assertEquals(a.length, 10);
}
check(Array.of());
check(Array.of(0));
check(Array.of(0, 1, 2));
var f = Array.of;
check(f());
// Array.of basics
var a = Array.of();
assertEquals(a.length, 0);
a = Array.of(undefined, null, 3.14, []);
assertEquals(a, [undefined, null, 3.14, []]);
a = [];
for (var i = 0; i < 1000; i++)
a[i] = i;
assertEquals(Array.of.apply(null, a), a);
// Array.of does not leave holes
assertEquals(Array.of(undefined), [undefined]);
assertEquals(Array.of(undefined, undefined), [undefined, undefined]);
assertEquals(Array.of.apply(null, [,,undefined]), [undefined, undefined, undefined]);
assertEquals(Array.of.apply(null, Array(4)), [undefined, undefined, undefined, undefined]);
// Array.of can be transplanted to other classes.
var hits = 0;
function Bag() {
hits++;
}
Bag.of = Array.of;
hits = 0;
var actual = Bag.of("zero", "one");
assertEquals(hits, 1);
hits = 0;
var expected = new Bag;
expected[0] = "zero";
expected[1] = "one";
expected.length = 2;
assertEquals(areSame(actual, expected), true);
hits = 0;
actual = Array.of.call(Bag, "zero", "one");
assertEquals(hits, 1);
assertEquals(areSame(actual, expected), true);
function areSame(object, array) {
var result = object.length == array.length;
for (var i = 0; i < object.length; i++) {
result = result && object[i] == array[i];
}
return result;
}
// Array.of does not trigger prototype setters.
// (It defines elements rather than assigning to them.)
var status = "pass";
Object.defineProperty(Array.prototype, "0", {set: function(v) {status = "FAIL 1"}});
assertEquals(Array.of(1)[0], 1);
assertEquals(status, "pass");
Object.defineProperty(Bag.prototype, "0", {set: function(v) {status = "FAIL 2"}});
assertEquals(Bag.of(1)[0], 1);
assertEquals(status, "pass");
// Array.of passes the number of arguments to the constructor it calls.
var hits = 0;
function Herd(n) {
assertEquals(arguments.length, 1);
assertEquals(n, 5);
hits++;
}
Herd.of = Array.of;
Herd.of("sheep", "cattle", "elephants", "whales", "seals");
assertEquals(hits, 1);
// Array.of calls a "length" setter if one is present.
var hits = 0;
var lastObj = null, lastVal = undefined;
function setter(v) {
hits++;
lastObj = this;
lastVal = v;
}
// when the setter is on the new object
function Pack() {
Object.defineProperty(this, "length", {set: setter});
}
Pack.of = Array.of;
var pack = Pack.of("wolves", "cards", "cigarettes", "lies");
assertEquals(lastObj, pack);
assertEquals(lastVal, 4);
// when the setter is on the new object's prototype
function Bevy() {}
Object.defineProperty(Bevy.prototype, "length", {set: setter});
Bevy.of = Array.of;
var bevy = Bevy.of("quail");
assertEquals(lastObj, bevy);
assertEquals(lastVal, 1);
// Array.of does a strict assignment to the new object's .length.
// The assignment is strict even if the code we're calling from is not strict.
function Empty() {}
Empty.of = Array.of;
Object.defineProperty(Empty.prototype, "length", {get: function() { return 0; }});
var nothing = new Empty;
nothing.length = 2; // no exception; this is not a strict mode assignment
assertThrows(function() { Empty.of(); }, TypeError);
// Check superficial features of Array.of.
var desc = Object.getOwnPropertyDescriptor(Array, "of");
assertEquals(desc.configurable, true);
assertEquals(desc.enumerable, false);
assertEquals(desc.writable, true);
assertEquals(Array.of.length, 0);
assertThrows(function() { new Array.of() }, TypeError); // not a constructor
// When the this-value passed in is not a constructor, the result is an array.
[undefined, null, false, "cow"].forEach(function(val) {
assertEquals(Array.isArray(Array.of(val)), true);
});
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