From bb94e6b7634e70a873881f406a955591ae401b0b Mon Sep 17 00:00:00 2001
From: vthinkxie <yadong.xyd@alibaba-inc.com>
Date: Thu, 17 Oct 2019 17:48:35 +0800
Subject: [PATCH] feat(core): support APP_INITIALIZER work with observable

add support to observable with APP_INITIALIZER

close #15088
---
 packages/core/src/application_init.ts       |  4 +-
 packages/core/test/application_init_spec.ts | 50 ++++++++++++++++++++-
 2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/packages/core/src/application_init.ts b/packages/core/src/application_init.ts
index d464573b44b0b2..d5531a1e0c47ff 100644
--- a/packages/core/src/application_init.ts
+++ b/packages/core/src/application_init.ts
@@ -7,7 +7,7 @@
  */
 
 import {Inject, Injectable, InjectionToken, Optional} from './di';
-import {isPromise} from './util/lang';
+import {isObservable, isPromise} from './util/lang';
 import {noop} from './util/noop';
 
 
@@ -68,6 +68,8 @@ export class ApplicationInitStatus {
         const initResult = this.appInits[i]();
         if (isPromise(initResult)) {
           asyncInitPromises.push(initResult);
+        } else if (isObservable(initResult)) {
+          asyncInitPromises.push(initResult.toPromise());
         }
       }
     }
diff --git a/packages/core/test/application_init_spec.ts b/packages/core/test/application_init_spec.ts
index ee078a606ea0f4..dbde730e20986f 100644
--- a/packages/core/test/application_init_spec.ts
+++ b/packages/core/test/application_init_spec.ts
@@ -7,6 +7,7 @@
  */
 import {Injector} from '@angular/core';
 import {APP_INITIALIZER, ApplicationInitStatus} from '@angular/core/src/application_init';
+import {Observable, Subscriber} from 'rxjs';
 
 import {inject, TestBed, waitForAsync} from '../testing';
 
@@ -28,7 +29,7 @@ import {inject, TestBed, waitForAsync} from '../testing';
          })));
     });
 
-    describe('with async initializers', () => {
+    describe('with async promise initializers', () => {
       let resolve: (result: any) => void;
       let promise: Promise<any>;
       let completerResolver = false;
@@ -57,7 +58,7 @@ import {inject, TestBed, waitForAsync} from '../testing';
         });
       });
 
-      it('should update the status once all async initializers are done',
+      it('should update the status once all async promise initializers are done',
          waitForAsync(inject([ApplicationInitStatus], (status: ApplicationInitStatus) => {
            (status as any).runInitializers();
 
@@ -66,6 +67,51 @@ import {inject, TestBed, waitForAsync} from '../testing';
              resolve(null);
            });
 
+           expect(status.done).toBe(false);
+           status.donePromise.then(() => {
+             expect(status.done).toBe(true);
+             expect(completerResolver).toBe(true);
+           });
+         })));
+    });
+    describe('with async observable initializers', () => {
+      let resolve: Subscriber<any>;
+      let observable: Observable<any>;
+      let completerResolver = false;
+      beforeEach(() => {
+        let initializerFactory = (injector: Injector) => {
+          return () => {
+            const initStatus = injector.get(ApplicationInitStatus);
+            initStatus.donePromise.then(() => {
+              expect(completerResolver).toBe(true);
+            });
+          };
+        };
+        observable = new Observable((res) => {
+          resolve = res;
+        });
+        TestBed.configureTestingModule({
+          providers: [
+            {provide: APP_INITIALIZER, multi: true, useValue: () => observable},
+            {
+              provide: APP_INITIALIZER,
+              multi: true,
+              useFactory: initializerFactory,
+              deps: [Injector]
+            },
+          ]
+        });
+      });
+
+      it('should update the status once all async observable initializers are done',
+         waitForAsync(inject([ApplicationInitStatus], (status: ApplicationInitStatus) => {
+           (status as any).runInitializers();
+
+           setTimeout(() => {
+             completerResolver = true;
+             resolve.complete();
+           });
+
            expect(status.done).toBe(false);
            status.donePromise.then(() => {
              expect(status.done).toBe(true);