fix(promise): can set native promise after loading zone.js

Author: JiaLiPassion

lib/common/promise.ts

@@ -330,6 +330,44 @@ Zone.__load_patch('ZoneAwarePromise', (global: any, Zone: ZoneType, api: _ZonePr
   ZoneAwarePromise['all'] = ZoneAwarePromise.all;
 
   const NativePromise = global[symbolPromise] = global['Promise'];
+  const ZONE_AWARE_PROMISE = Zone.__symbol__('ZoneAwarePromise');
+
+  let desc = Object.getOwnPropertyDescriptor(global, 'Promise');
+  if (!desc || desc.configurable) {
+    desc && delete desc.writable;
+    desc && delete desc.value;
+    if (!desc) {
+      desc = {configurable: true, enumerable: true};
+    }
+    desc.get = function() {
+      // if we already set ZoneAwarePromise, use patched one
+      // otherwise return native one.
+      return global[ZONE_AWARE_PROMISE] ? global[ZONE_AWARE_PROMISE] : global[symbolPromise];
+    };
+    desc.set = function(NewNativePromise) {
+      if (NewNativePromise === ZoneAwarePromise) {
+        // if the NewNativePromise is ZoneAwarePromise
+        // save to global
+        global[ZONE_AWARE_PROMISE] = NewNativePromise;
+      } else {
+        // if the NewNativePromise is not ZoneAwarePromise
+        // for example: after load zone.js, some library just
+        // set es6-promise to global, if we set it to global
+        // directly, assertZonePatched will fail and angular
+        // will not loaded, so we just set the NewNativePromise
+        // to global[symbolPromise], so the result is just like
+        // we load ES6 Promise before zone.js
+        global[symbolPromise] = NewNativePromise;
+        if (!NewNativePromise.prototype[symbolThen]) {
+          patchThen(NewNativePromise);
+        }
+        api.setNativePromise(NewNativePromise);
+      }
+    };
+
+    Object.defineProperty(global, 'Promise', desc);
+  }
+
   global['Promise'] = ZoneAwarePromise;
 
   const symbolThenPatched = __symbol__('thenPatched');

lib/zone.ts

@@ -322,6 +322,7 @@ interface _ZonePrivate {
   showUncaughtError: () => boolean;
   patchEventTarget: (global: any, apis: any[], options?: any) => boolean[];
   patchOnProperties: (obj: any, properties: string[]) => void;
+  setNativePromise: (nativePromise: any) => void;
   patchMethod:
       (target: any, name: string,
        patchFn: (delegate: Function, delegateName: string, name: string) =>
@@ -1318,6 +1319,9 @@ const Zone: ZoneType = (function(global: any) {
     patchEventTarget: () => [],
     patchOnProperties: noop,
     patchMethod: () => noop,
+    setNativePromise: (NativePromise: any) => {
+      nativeMicroTaskQueuePromise = NativePromise.resolve(0);
+    },
   };
   let _currentZoneFrame: _ZoneFrame = {parent: null, zone: new Zone(null, null)};
   let _currentTask: Task = null;

test/common/Promise.spec.ts

@@ -6,7 +6,9 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {zoneSymbol} from '../../lib/common/utils';
 import {ifEnvSupports} from '../test-util';
+
 declare const global: any;
 
 class MicroTaskQueueZoneSpec implements ZoneSpec {
@@ -56,6 +58,31 @@ describe(
         log = [];
       });
 
+      xit('should allow set es6 Promise after load ZoneAwarePromise', (done) => {
+        const ES6Promise = require('es6-promise').Promise;
+        const NativePromise = global[zoneSymbol('Promise')];
+
+        try {
+          global['Promise'] = ES6Promise;
+          Zone.assertZonePatched();
+          expect(global[zoneSymbol('Promise')]).toBe(ES6Promise);
+          const promise = Promise.resolve(0);
+          console.log('promise', promise);
+          promise
+              .then(value => {
+                expect(value).toBe(0);
+                done();
+              })
+              .catch(error => {
+                fail(error);
+              });
+        } finally {
+          global['Promise'] = NativePromise;
+          Zone.assertZonePatched();
+          expect(global[zoneSymbol('Promise')]).toBe(NativePromise);
+        }
+      });
+
       it('should pretend to be a native code', () => {
         expect(String(Promise).indexOf('[native code]') >= 0).toBe(true);
       });

test/common/zone.spec.ts

@@ -5,6 +5,7 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
+import {zoneSymbol} from '../../lib/common/utils';
 
 describe('Zone', function() {
   const rootZone = Zone.current;
@@ -326,17 +327,23 @@ describe('Zone', function() {
         Zone.assertZonePatched();
       });
 
-      it('should throw when Promise has been patched', () => {
-        class WrongPromise {}
+      it('should keep ZoneAwarePromise has been patched', () => {
+        class WrongPromise {
+          static resolve(value: any) {}
+
+          then() {}
+        }
 
         const ZoneAwarePromise = global.Promise;
+        const NativePromise = (global as any)[zoneSymbol('Promise')];
         global.Promise = WrongPromise;
         try {
           expect(ZoneAwarePromise).toBeTruthy();
-          expect(() => Zone.assertZonePatched()).toThrow();
+          Zone.assertZonePatched();
+          expect(global.Promise).toBe(ZoneAwarePromise);
         } finally {
           // restore it.
-          global.Promise = ZoneAwarePromise;
+          global.Promise = NativePromise;
         }
         Zone.assertZonePatched();
       });