Revert "refactor: use isObservable provided by rxjs 6.1+ (angular#27668)"

This reverts commit 92c5478.

Author: mhevery

integration/side-effects/snapshots/common/esm2015.js

@@ -1,3 +1 @@
 import "@angular/core";
-
-import "rxjs";

integration/side-effects/snapshots/common/esm5.js

@@ -1,5 +1,3 @@
 import "tslib";
 
 import "@angular/core";
-
-import "rxjs";

packages/common/src/pipes/async_pipe.ts

@@ -6,8 +6,8 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ChangeDetectorRef, EventEmitter, OnDestroy, Pipe, PipeTransform, WrappedValue, ɵisPromise, ɵlooseIdentical} from '@angular/core';
-import {Observable, SubscriptionLike, isObservable} from 'rxjs';
+import {ChangeDetectorRef, EventEmitter, OnDestroy, Pipe, PipeTransform, WrappedValue, ɵisObservable, ɵisPromise, ɵlooseIdentical} from '@angular/core';
+import {Observable, SubscriptionLike} from 'rxjs';
 import {invalidPipeArgumentError} from './invalid_pipe_argument_error';
 
 interface SubscriptionStrategy {
@@ -122,7 +122,7 @@ export class AsyncPipe implements OnDestroy, PipeTransform {
       return _promiseStrategy;
     }
 
-    if (isObservable(obj)) {
+    if (ɵisObservable(obj)) {
       return _observableStrategy;
     }
 

packages/core/src/core_private_export.ts

@@ -30,7 +30,7 @@ export {global as ɵglobal} from './util/global';
 export {looseIdentical as ɵlooseIdentical,} from './util/comparison';
 export {stringify as ɵstringify} from './util/stringify';
 export {makeDecorator as ɵmakeDecorator} from './util/decorators';
-export {isPromise as ɵisPromise} from './util/lang';
+export {isObservable as ɵisObservable, isPromise as ɵisPromise} from './util/lang';
 export {clearOverrides as ɵclearOverrides, initServicesIfNeeded as ɵinitServicesIfNeeded, overrideComponentView as ɵoverrideComponentView, overrideProvider as ɵoverrideProvider} from './view/index';
 export {NOT_FOUND_CHECK_ONLY_ELEMENT_INJECTOR as ɵNOT_FOUND_CHECK_ONLY_ELEMENT_INJECTOR} from './view/provider';
 export {LocaleDataIndex as ɵLocaleDataIndex, CurrencyIndex as ɵCurrencyIndex, ExtraLocaleDataIndex as ɵExtraLocaleDataIndex, getLocalePluralCase as ɵgetLocalePluralCase, findLocaleData as ɵfindLocaleData, registerLocaleData as ɵregisterLocaleData, unregisterAllLocaleData as ɵunregisterLocaleData} from './i18n/locale_data_api';

packages/core/src/render3/instructions/listener.ts

@@ -6,8 +6,9 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {isObservable} from 'rxjs';
+
 import {assertDataInRange} from '../../util/assert';
+import {isObservable} from '../../util/lang';
 import {EMPTY_OBJ} from '../empty';
 import {PropertyAliasValue, TNode, TNodeFlags, TNodeType} from '../interfaces/node';
 import {GlobalTargetResolver, RElement, Renderer3, isProceduralRenderer} from '../interfaces/renderer';

packages/core/src/util/BUILD.bazel

@@ -15,5 +15,6 @@ ts_library(
     deps = [
         "//packages:types",
         "//packages/core/src/interface",
+        "@npm//rxjs",
     ],
 )

packages/core/src/util/lang.ts

@@ -6,6 +6,8 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {Observable} from 'rxjs';
+
 /**
  * Determine if the argument is shaped like a Promise
  */
@@ -14,3 +16,12 @@ export function isPromise(obj: any): obj is Promise<any> {
   // It's up to the caller to ensure that obj.then conforms to the spec
   return !!obj && typeof obj.then === 'function';
 }
+
+/**
+ * Determine if the argument is an Observable
+ */
+export function isObservable(obj: any | Observable<any>): obj is Observable<any> {
+  // TODO: use isObservable once we update pass rxjs 6.1
+  // https://github.com/ReactiveX/rxjs/blob/master/CHANGELOG.md#610-2018-05-03
+  return !!obj && typeof obj.subscribe === 'function';
+}

packages/core/src/view/provider.ts

@@ -6,13 +6,13 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {isObservable} from 'rxjs';
 import {ChangeDetectorRef, SimpleChange, SimpleChanges, WrappedValue} from '../change_detection/change_detection';
 import {INJECTOR, Injector, resolveForwardRef} from '../di';
 import {ElementRef} from '../linker/element_ref';
 import {TemplateRef} from '../linker/template_ref';
 import {ViewContainerRef} from '../linker/view_container_ref';
 import {Renderer2} from '../render/api';
+import {isObservable} from '../util/lang';
 import {stringify} from '../util/stringify';
 
 import {createChangeDetectorRef, createInjector} from './refs';

packages/core/test/util/lang_spec.ts

@@ -5,7 +5,8 @@
  * 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 {isPromise} from '@angular/core/src/util/lang';
+import {isObservable, isPromise} from '@angular/core/src/util/lang';
+import {of } from 'rxjs';
 
 {
   describe('isPromise', () => {
@@ -25,4 +26,22 @@ import {isPromise} from '@angular/core/src/util/lang';
       expect(isPromise(null)).toEqual(false);
     });
   });
+
+  describe('isObservable', () => {
+    it('should be true for an Observable', () => expect(isObservable(of (true))).toEqual(true));
+
+    it('should be true if the argument is the object with subscribe function',
+       () => expect(isObservable({subscribe: () => {}})).toEqual(true));
+
+    it('should be false if the argument is undefined',
+       () => expect(isObservable(undefined)).toEqual(false));
+
+    it('should be false if the argument is null', () => expect(isObservable(null)).toEqual(false));
+
+    it('should be false if the argument is an object',
+       () => expect(isObservable({})).toEqual(false));
+
+    it('should be false if the argument is a function',
+       () => expect(isObservable(() => {})).toEqual(false));
+  });
 }

packages/core/test/view/BUILD.bazel

@@ -17,7 +17,6 @@ ts_library(
         "//packages/core/testing",
         "//packages/platform-browser",
         "//packages/private/testing",
-        "@npm//rxjs",
     ],
 )