v8/test/mjsunit/harmony/async-arrow-lexical-this.js
2016-05-17 00:27:51 +00:00

49 lines
1.3 KiB
JavaScript

// Copyright 2016 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-async-await --allow-natives-syntax
function assertEqualsAsync(expected, run, msg) {
var actual;
var hadValue = false;
var hadError = false;
var promise = run();
if (typeof promise !== "object" || typeof promise.then !== "function") {
throw new MjsUnitAssertionError(
"Expected " + run.toString() +
" to return a Promise, but it returned " + PrettyPrint(promise));
}
promise.then(function(value) { hadValue = true; actual = value; },
function(error) { hadError = true; actual = error; });
assertFalse(hadValue || hadError);
%RunMicrotasks();
if (hadError) throw actual;
assertTrue(
hadValue, "Expected '" + run.toString() + "' to produce a value");
assertEquals(expected, actual, msg);
};
var O = {
[Symbol.toStringTag]: "LexicalThis",
run(n) {
return async passFail => `${n}. ${passFail}: ${this}`;
},
};
assertEqualsAsync("1. PASS: [object LexicalThis]", () => O.run(1)("PASS"));
var O2 = {
[Symbol.toStringTag]: "LexicalThis",
run: O.run(2)
};
assertEqualsAsync("2. PASS: [object LexicalThis]", () => O2.run("PASS"));