Merge pull request #2238 from zsxwing/issue2191

Fix the bug that cache doesn't unsubscribe the source Observable when th...

src/main/java/rx/internal/operators/OnSubscribeCache.java

@@ -64,9 +64,10 @@ public OnSubscribeCache(Observable<? extends T> source, int capacity) {
     @Override
     public void call(Subscriber<? super T> s) {
         if (SRC_SUBSCRIBED_UPDATER.compareAndSet(this, 0, 1)) {
-            source.unsafeSubscribe(Subscribers.from(cache));
+            source.subscribe(cache);
             /*
-             * Note that we will never unsubscribe from 'source' as we want to receive and cache all of its values.
+             * Note that we will never unsubscribe from 'source' unless we receive `onCompleted` or `onError`,
+             * as we want to receive and cache all of its values.
              * 
              * This means this should never be used on an infinite or very large sequence, similar to toList().
              */

src/test/java/rx/internal/operators/OnSubscribeCacheTest.java

@@ -17,6 +17,9 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
 
 import java.util.Arrays;
 import java.util.concurrent.CountDownLatch;
@@ -27,10 +30,10 @@
 
 import rx.Observable;
 import rx.Subscriber;
+import rx.functions.Action0;
 import rx.functions.Action1;
 import rx.functions.Func1;
 import rx.functions.Func2;
-import rx.internal.operators.OnSubscribeCache;
 import rx.observers.TestSubscriber;
 import rx.schedulers.Schedulers;
 import rx.subjects.AsyncSubject;
@@ -148,4 +151,14 @@ public void testWithPublishSubjectAndRepeat() {
     public void testWithReplaySubjectAndRepeat() {
         testWithCustomSubjectAndRepeat(ReplaySubject.<Integer> create(), 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3);
     }
+
+    @Test
+    public void testUnsubscribeSource() {
+        Action0 unsubscribe = mock(Action0.class);
+        Observable<Integer> o = Observable.just(1).doOnUnsubscribe(unsubscribe).cache();
+        o.subscribe();
+        o.subscribe();
+        o.subscribe();
+        verify(unsubscribe, times(1)).call();
+    }
 }