Merge pull request #501 from bocoup/prms-then-ctor-access-count

Promise: Add test for constructor access count

test/built-ins/Promise/prototype/then/ctor-access-count.js

+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 25.4.5.3
+description: The instance's `constructor` property is accessed exactly once
+info: >
+    1. Let promise be the this value.
+    2. If IsPromise(promise) is false, throw a TypeError exception.
+    3. Let C be SpeciesConstructor(promise, %Promise%).
+    4. ReturnIfAbrupt(C).
+    5. Let resultCapability be NewPromiseCapability(C).
+    6. ReturnIfAbrupt(resultCapability).
+    7. Return PerformPromiseThen(promise, onFulfilled, onRejected,
+       resultCapability).
+
+    7.3.20 SpeciesConstructor ( O, defaultConstructor )
+
+    1. Assert: Type(O) is Object.
+    2. Let C be Get(O, "constructor").
+    3. ReturnIfAbrupt(C).
+    4. If C is undefined, return defaultConstructor.
+    5. If Type(C) is not Object, throw a TypeError exception.
+    6. Let S be Get(C, @@species).
+    7. ReturnIfAbrupt(S).
+    8. If S is either undefined or null, return defaultConstructor.
+    9. If IsConstructor(S) is true, return S.
+    10. Throw a TypeError exception.
+---*/
+
+var callCount = 0;
+var prms = new Promise(function(resolve) { resolve(); });
+Object.defineProperty(prms, 'constructor', {
+  get: function() {
+    callCount += 1;
+    return Promise;
+  }
+});
+
+prms.then(function() {
+    if (callCount !== 1) {
+      $DONE('Expected constructor access count: 1. Actual: ' + callCount);
+      return;
+    }
+
+    $DONE();
+  }, function() {
+    $DONE('The promise should not be rejected.');
+  });