diff --git a/spec/Subject-spec.js b/spec/Subject-spec.js index e31fb505044..5eea7b4b0b9 100644 --- a/spec/Subject-spec.js +++ b/spec/Subject-spec.js @@ -1,4 +1,4 @@ -/* globals describe, it, expect */ +/* globals describe, it, expect, hot, expectObservable */ var Rx = require('../dist/cjs/Rx'); var Subject = Rx.Subject; @@ -508,4 +508,77 @@ describe('Subject', function () { source.subscribe(subject); }); + + describe('asObservable', function () { + it('should hide subject', function () { + var subject = new Rx.Subject(); + expect(subject).not.toEqual(subject.asObservable()); + }); + + it('should handle subject never emits', function () { + var observable = hot('-').asObservable(); + + expectObservable(observable).toBe([]); + }); + + it('should handle subject completes without emits', function () { + var observable = hot('--^--|').asObservable(); + var expected = '---|'; + + expectObservable(observable).toBe(expected); + }); + + it('should handle subject throws', function () { + var observable = hot('--^--#').asObservable(); + var expected = '---#'; + + expectObservable(observable).toBe(expected); + }); + + it('should handle subject emits', function () { + var observable = hot('--^--x--|').asObservable(); + var expected = '---x--|'; + + expectObservable(observable).toBe(expected); + }); + + it('should work with inherited subject', function (done) { + var subject = new Rx.AsyncSubject(); + + subject.next(42); + subject.complete(); + + var observable = subject.asObservable(); + + var expected = [new Rx.Notification('N', 42), + new Rx.Notification('C')]; + + observable.materialize().subscribe(function (x) { + expect(x).toEqual(expected.shift()); + }, function (err) { + done.fail(err); + }, function () { + expect(expected).toEqual([]); + done(); + }); + }); + + it('should not eager', function () { + var subscribed = false; + + var subject = new Rx.Subject(new Rx.Observable(function (observer) { + subscribed = true; + var subscription = Rx.Observable.of('x').subscribe(observer); + return function () { + subscription.unsubscribe(); + }; + })); + + var observable = subject.asObservable(); + expect(subscribed).toBe(false); + + observable.subscribe(); + expect(subscribed).toBe(true); + }); + }); }); diff --git a/src/Subject.ts b/src/Subject.ts index e8dc2422280..d52cbe41d4c 100644 --- a/src/Subject.ts +++ b/src/Subject.ts @@ -123,6 +123,12 @@ export class Subject extends Observable implements Observer, Subscripti this._complete(); } + asObservable(): Observable { + return new Observable((observer: Observer) => { + this.subscribe(observer); + }); + } + protected _next(value: T): void { if (this.destination) { this.destination.next(value);