v8/test/mjsunit/harmony/arrow-functions.js
caitpotter88 9836c34dba [es6] do not add caller/arguments to ES6 function definitions
BUG=v8:3946, v8:3982
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
LOG=N
R=arv@chromium.org, rossberg@chromium.org

Review URL: https://codereview.chromium.org/1027283004

Cr-Commit-Position: refs/heads/master@{#27729}
2015-04-09 22:40:28 +00:00

73 lines
2.6 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-arrow-functions
// Arrow functions are like functions, except they throw when using the
// "new" operator on them.
assertEquals("function", typeof (() => {}));
assertEquals(Function.prototype, Object.getPrototypeOf(() => {}));
assertThrows(function() { new (() => {}); }, TypeError);
assertFalse("prototype" in (() => {}));
// Check the different syntax variations
assertEquals(1, (() => 1)());
assertEquals(2, (a => a + 1)(1));
assertEquals(3, (() => { return 3; })());
assertEquals(4, (a => { return a + 3; })(1));
assertEquals(5, ((a, b) => a + b)(1, 4));
assertEquals(6, ((a, b) => { return a + b; })(1, 5));
// The following are tests from:
// http://wiki.ecmascript.org/doku.php?id=harmony:arrow_function_syntax
// Empty arrow function returns undefined
var empty = () => {};
assertEquals(undefined, empty());
// Single parameter case needs no parentheses around parameter list
var identity = x => x;
assertEquals(empty, identity(empty));
// No need for parentheses even for lower-precedence expression body
var square = x => x * x;
assertEquals(9, square(3));
// Parenthesize the body to return an object literal expression
var key_maker = val => ({key: val});
assertEquals(empty, key_maker(empty).key);
// Statement body needs braces, must use 'return' explicitly if not void
var evens = [0, 2, 4, 6, 8];
assertEquals([1, 3, 5, 7, 9], evens.map(v => v + 1));
var fives = [];
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10].forEach(v => {
if (v % 5 === 0) fives.push(v);
});
assertEquals([5, 10], fives);
(function testRestrictedFunctionPropertiesStrict() {
var arrowFn = () => { "use strict"; };
assertFalse(arrowFn.hasOwnProperty("arguments"));
assertThrows(function() { return arrowFn.arguments; }, TypeError);
assertThrows(function() { arrowFn.arguments = {}; }, TypeError);
assertFalse(arrowFn.hasOwnProperty("caller"));
assertThrows(function() { return arrowFn.caller; }, TypeError);
assertThrows(function() { arrowFn.caller = {}; }, TypeError);
})();
(function testRestrictedFunctionPropertiesSloppy() {
var arrowFn = () => {};
assertFalse(arrowFn.hasOwnProperty("arguments"));
assertThrows(function() { return arrowFn.arguments; }, TypeError);
assertThrows(function() { arrowFn.arguments = {}; }, TypeError);
assertFalse(arrowFn.hasOwnProperty("caller"));
assertThrows(function() { return arrowFn.caller; }, TypeError);
assertThrows(function() { arrowFn.caller = {}; }, TypeError);
})();