/**
* Copyright 2014 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package rx.subjects;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.inOrder;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyNoMoreInteractions;
import java.util.Arrays;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
import org.junit.Test;
import org.mockito.InOrder;
import org.mockito.Mockito;
import rx.Observable;
import rx.Observer;
import rx.Subscriber;
import rx.Subscription;
import rx.exceptions.CompositeException;
import rx.exceptions.OnErrorNotImplementedException;
import rx.exceptions.TestException;
import rx.functions.Func1;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
import rx.schedulers.TestScheduler;
public class ReplaySubjectTest {
private final Throwable testException = new Throwable();
@SuppressWarnings("unchecked")
@Test
public void testCompleted() {
ReplaySubject<String> subject = ReplaySubject.create();
Observer<String> o1 = mock(Observer.class);
subject.subscribe(o1);
subject.onNext("one");
subject.onNext("two");
subject.onNext("three");
subject.onCompleted();
subject.onNext("four");
subject.onCompleted();
subject.onError(new Throwable());
assertCompletedObserver(o1);
// assert that subscribing a 2nd time gets the same data
Observer<String> o2 = mock(Observer.class);
subject.subscribe(o2);
assertCompletedObserver(o2);
}
@Test
public void testCompletedStopsEmittingData() {
ReplaySubject<Integer> channel = ReplaySubject.create();
@SuppressWarnings("unchecked")
Observer<Object> observerA = mock(Observer.class);
@SuppressWarnings("unchecked")
Observer<Object> observerB = mock(Observer.class);
@SuppressWarnings("unchecked")
Observer<Object> observerC = mock(Observer.class);
@SuppressWarnings("unchecked")
Observer<Object> observerD = mock(Observer.class);
Subscription a = channel.subscribe(observerA);
channel.subscribe(observerB);
InOrder inOrderA = inOrder(observerA);
InOrder inOrderB = inOrder(observerB);
InOrder inOrderC = inOrder(observerC);
InOrder inOrderD = inOrder(observerD);
channel.onNext(42);
// both A and B should have received 42 from before subscription
inOrderA.verify(observerA).onNext(42);
inOrderB.verify(observerB).onNext(42);
a.unsubscribe();
// a should receive no more
inOrderA.verifyNoMoreInteractions();
channel.onNext(4711);
// only be should receive 4711 at this point
inOrderB.verify(observerB).onNext(4711);
channel.onCompleted();
// B is subscribed so should receive onCompleted
inOrderB.verify(observerB).onCompleted();
channel.subscribe(observerC);
// when C subscribes it should receive 42, 4711, onCompleted
inOrderC.verify(observerC).onNext(42);
inOrderC.verify(observerC).onNext(4711);
inOrderC.verify(observerC).onCompleted();
// if further events are propagated they should be ignored
channel.onNext(13);
channel.onNext(14);
channel.onNext(15);
channel.onError(new RuntimeException());
// a new subscription should only receive what was emitted prior to terminal state onCompleted
channel.subscribe(observerD);
inOrderD.verify(observerD).onNext(42);
inOrderD.verify(observerD).onNext(4711);
inOrderD.verify(observerD).onCompleted();
Mockito.verifyNoMoreInteractions(observerA);
Mockito.verifyNoMoreInteractions(observerB);
Mockito.verifyNoMoreInteractions(observerC);
Mockito.verifyNoMoreInteractions(observerD);
}
@Test
public void testCompletedAfterError() {
ReplaySubject<String> subject = ReplaySubject.create();
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.onNext("one");
subject.onError(testException);
subject.onNext("two");
subject.onCompleted();
subject.onError(new RuntimeException());
subject.subscribe(observer);
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onError(testException);
verifyNoMoreInteractions(observer);
}
private void assertCompletedObserver(Observer<String> observer) {
InOrder inOrder = inOrder(observer);
inOrder.verify(observer, times(1)).onNext("one");
inOrder.verify(observer, times(1)).onNext("two");
inOrder.verify(observer, times(1)).onNext("three");
inOrder.verify(observer, Mockito.never()).onError(any(Throwable.class));
inOrder.verify(observer, times(1)).onCompleted();
inOrder.verifyNoMoreInteractions();
}
@SuppressWarnings("unchecked")
@Test
public void testError() {
ReplaySubject<String> subject = ReplaySubject.create();
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onNext("two");
subject.onNext("three");
subject.onError(testException);
subject.onNext("four");
subject.onError(new Throwable());
subject.onCompleted();
assertErrorObserver(observer);
observer = mock(Observer.class);
subject.subscribe(observer);
assertErrorObserver(observer);
}
private void assertErrorObserver(Observer<String> observer) {
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onNext("two");
verify(observer, times(1)).onNext("three");
verify(observer, times(1)).onError(testException);
verify(observer, Mockito.never()).onCompleted();
}
@SuppressWarnings("unchecked")
@Test
public void testSubscribeMidSequence() {
ReplaySubject<String> subject = ReplaySubject.create();
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onNext("two");
assertObservedUntilTwo(observer);
Observer<String> anotherObserver = mock(Observer.class);
subject.subscribe(anotherObserver);
assertObservedUntilTwo(anotherObserver);
subject.onNext("three");
subject.onCompleted();
assertCompletedObserver(observer);
assertCompletedObserver(anotherObserver);
}
@SuppressWarnings("unchecked")
@Test
public void testUnsubscribeFirstObserver() {
ReplaySubject<String> subject = ReplaySubject.create();
Observer<String> observer = mock(Observer.class);
Subscription subscription = subject.subscribe(observer);
subject.onNext("one");
subject.onNext("two");
subscription.unsubscribe();
assertObservedUntilTwo(observer);
Observer<String> anotherObserver = mock(Observer.class);
subject.subscribe(anotherObserver);
assertObservedUntilTwo(anotherObserver);
subject.onNext("three");
subject.onCompleted();
assertObservedUntilTwo(observer);
assertCompletedObserver(anotherObserver);
}
private void assertObservedUntilTwo(Observer<String> observer) {
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onNext("two");
verify(observer, Mockito.never()).onNext("three");
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, Mockito.never()).onCompleted();
}
@Test(timeout = 2000)
public void testNewSubscriberDoesntBlockExisting() throws InterruptedException {
final AtomicReference<String> lastValueForObserver1 = new AtomicReference<String>();
Subscriber<String> observer1 = new Subscriber<String>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(String v) {
System.out.println("observer1: " + v);
lastValueForObserver1.set(v);
}
};
final AtomicReference<String> lastValueForObserver2 = new AtomicReference<String>();
final CountDownLatch oneReceived = new CountDownLatch(1);
final CountDownLatch makeSlow = new CountDownLatch(1);
final CountDownLatch completed = new CountDownLatch(1);
Subscriber<String> observer2 = new Subscriber<String>() {
@Override
public void onCompleted() {
completed.countDown();
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(String v) {
System.out.println("observer2: " + v);
if (v.equals("one")) {
oneReceived.countDown();
} else {
try {
makeSlow.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
lastValueForObserver2.set(v);
}
}
};
ReplaySubject<String> subject = ReplaySubject.create();
subject.subscribe(observer1);
subject.onNext("one");
assertEquals("one", lastValueForObserver1.get());
subject.onNext("two");
assertEquals("two", lastValueForObserver1.get());
// use subscribeOn to make this async otherwise we deadlock as we are using CountDownLatches
subject.subscribeOn(Schedulers.newThread()).subscribe(observer2);
System.out.println("before waiting for one");
// wait until observer2 starts having replay occur
oneReceived.await();
System.out.println("after waiting for one");
subject.onNext("three");
System.out.println("sent three");
// if subscription blocked existing subscribers then 'makeSlow' would cause this to not be there yet
assertEquals("three", lastValueForObserver1.get());
System.out.println("about to send onCompleted");
subject.onCompleted();
System.out.println("completed subject");
// release
makeSlow.countDown();
System.out.println("makeSlow released");
completed.await();
// all of them should be emitted with the last being "three"
assertEquals("three", lastValueForObserver2.get());
}
@Test
public void testSubscriptionLeak() {
ReplaySubject<Object> replaySubject = ReplaySubject.create();
Subscription s = replaySubject.subscribe();
assertEquals(1, replaySubject.subscriberCount());
s.unsubscribe();
assertEquals(0, replaySubject.subscriberCount());
}
@Test(timeout = 1000)
public void testUnsubscriptionCase() {
ReplaySubject<String> src = ReplaySubject.create();
for (int i = 0; i < 10; i++) {
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
InOrder inOrder = inOrder(o);
String v = "" + i;
src.onNext(v);
System.out.printf("Turn: %d%n", i);
src.first()
.flatMap(new Func1<String, Observable<String>>() {
@Override
public Observable<String> call(String t1) {
return Observable.just(t1 + ", " + t1);
}
})
.subscribe(new Observer<String>() {
@Override
public void onNext(String t) {
System.out.println(t);
o.onNext(t);
}
@Override
public void onError(Throwable e) {
o.onError(e);
}
@Override
public void onCompleted() {
o.onCompleted();
}
});
inOrder.verify(o).onNext("0, 0");
inOrder.verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
}
@Test
public void testTerminateOnce() {
ReplaySubject<Integer> source = ReplaySubject.create();
source.onNext(1);
source.onNext(2);
source.onCompleted();
@SuppressWarnings("unchecked")
final Observer<Integer> o = mock(Observer.class);
source.unsafeSubscribe(new Subscriber<Integer>() {
@Override
public void onNext(Integer t) {
o.onNext(t);
}
@Override
public void onError(Throwable e) {
o.onError(e);
}
@Override
public void onCompleted() {
o.onCompleted();
}
});
verify(o).onNext(1);
verify(o).onNext(2);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
@Test
public void testNodeListSimpleAddRemove() {
ReplaySubject.NodeList<Integer> list = new ReplaySubject.NodeList<Integer>();
assertEquals(0, list.size());
// add and remove one
list.addLast(1);
assertEquals(1, list.size());
assertEquals((Integer)1, list.removeFirst());
assertEquals(0, list.size());
// add and remove one again
list.addLast(1);
assertEquals(1, list.size());
assertEquals((Integer)1, list.removeFirst());
// add and remove two items
list.addLast(1);
list.addLast(2);
assertEquals(2, list.size());
assertEquals((Integer)1, list.removeFirst());
assertEquals((Integer)2, list.removeFirst());
assertEquals(0, list.size());
// clear two items
list.addLast(1);
list.addLast(2);
assertEquals(2, list.size());
list.clear();
assertEquals(0, list.size());
}
@Test
public void testReplay1AfterTermination() {
ReplaySubject<Integer> source = ReplaySubject.createWithSize(1);
source.onNext(1);
source.onNext(2);
source.onCompleted();
for (int i = 0; i < 1; i++) {
@SuppressWarnings("unchecked")
Observer<Integer> o = mock(Observer.class);
source.subscribe(o);
verify(o, never()).onNext(1);
verify(o).onNext(2);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
}
@Test
public void testReplay1Directly() {
ReplaySubject<Integer> source = ReplaySubject.createWithSize(1);
@SuppressWarnings("unchecked")
Observer<Integer> o = mock(Observer.class);
source.onNext(1);
source.onNext(2);
source.subscribe(o);
source.onNext(3);
source.onCompleted();
verify(o, never()).onNext(1);
verify(o).onNext(2);
verify(o).onNext(3);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
@Test
public void testReplayTimestampedAfterTermination() {
TestScheduler scheduler = new TestScheduler();
ReplaySubject<Integer> source = ReplaySubject.createWithTime(1, TimeUnit.SECONDS, scheduler);
source.onNext(1);
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
source.onNext(2);
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
source.onNext(3);
source.onCompleted();
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
@SuppressWarnings("unchecked")
Observer<Integer> o = mock(Observer.class);
source.subscribe(o);
verify(o, never()).onNext(1);
verify(o, never()).onNext(2);
verify(o).onNext(3);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
@Test
public void testReplayTimestampedDirectly() {
TestScheduler scheduler = new TestScheduler();
ReplaySubject<Integer> source = ReplaySubject.createWithTime(1, TimeUnit.SECONDS, scheduler);
source.onNext(1);
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
@SuppressWarnings("unchecked")
Observer<Integer> o = mock(Observer.class);
source.subscribe(o);
source.onNext(2);
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
source.onNext(3);
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
source.onCompleted();
scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
verify(o, never()).onError(any(Throwable.class));
verify(o, never()).onNext(1);
verify(o).onNext(2);
verify(o).onNext(3);
verify(o).onCompleted();
}
@Test
public void testOnErrorThrowsDoesntPreventDelivery() {
ReplaySubject<String> ps = ReplaySubject.create();
ps.subscribe();
TestSubscriber<String> ts = new TestSubscriber<String>();
ps.subscribe(ts);
try {
ps.onError(new RuntimeException("an exception"));
fail("expect OnErrorNotImplementedException");
} catch (OnErrorNotImplementedException e) {
// ignore
}
// even though the onError above throws we should still receive it on the other subscriber
assertEquals(1, ts.getOnErrorEvents().size());
}
/**
* This one has multiple failures so should get a CompositeException
*/
@Test
public void testOnErrorThrowsDoesntPreventDelivery2() {
ReplaySubject<String> ps = ReplaySubject.create();
ps.subscribe();
ps.subscribe();
TestSubscriber<String> ts = new TestSubscriber<String>();
ps.subscribe(ts);
ps.subscribe();
ps.subscribe();
ps.subscribe();
try {
ps.onError(new RuntimeException("an exception"));
fail("expect OnErrorNotImplementedException");
} catch (CompositeException e) {
// we should have 5 of them
assertEquals(5, e.getExceptions().size());
}
// even though the onError above throws we should still receive it on the other subscriber
assertEquals(1, ts.getOnErrorEvents().size());
}
@Test
public void testCurrentStateMethodsNormal() {
ReplaySubject<Object> as = ReplaySubject.create();
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getThrowable());
as.onNext(1);
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getThrowable());
as.onCompleted();
assertFalse(as.hasThrowable());
assertTrue(as.hasCompleted());
assertNull(as.getThrowable());
}
@Test
public void testCurrentStateMethodsEmpty() {
ReplaySubject<Object> as = ReplaySubject.create();
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getThrowable());
as.onCompleted();
assertFalse(as.hasThrowable());
assertTrue(as.hasCompleted());
assertNull(as.getThrowable());
}
@Test
public void testCurrentStateMethodsError() {
ReplaySubject<Object> as = ReplaySubject.create();
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getThrowable());
as.onError(new TestException());
assertTrue(as.hasThrowable());
assertFalse(as.hasCompleted());
assertTrue(as.getThrowable() instanceof TestException);
}
@Test
public void testSizeAndHasAnyValueUnbounded() {
ReplaySubject<Object> rs = ReplaySubject.create();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
rs.onNext(1);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
rs.onNext(1);
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
rs.onCompleted();
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueEffectivelyUnbounded() {
ReplaySubject<Object> rs = ReplaySubject.createUnbounded();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
rs.onNext(1);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
rs.onNext(1);
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
rs.onCompleted();
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueUnboundedError() {
ReplaySubject<Object> rs = ReplaySubject.create();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
rs.onNext(1);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
rs.onNext(1);
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
rs.onError(new TestException());
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueEffectivelyUnboundedError() {
ReplaySubject<Object> rs = ReplaySubject.createUnbounded();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
rs.onNext(1);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
rs.onNext(1);
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
rs.onError(new TestException());
assertEquals(2, rs.size());
assertTrue(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueUnboundedEmptyError() {
ReplaySubject<Object> rs = ReplaySubject.create();
rs.onError(new TestException());
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueEffectivelyUnboundedEmptyError() {
ReplaySubject<Object> rs = ReplaySubject.createUnbounded();
rs.onError(new TestException());
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueUnboundedEmptyCompleted() {
ReplaySubject<Object> rs = ReplaySubject.create();
rs.onCompleted();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueEffectivelyUnboundedEmptyCompleted() {
ReplaySubject<Object> rs = ReplaySubject.createUnbounded();
rs.onCompleted();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueSizeBounded() {
ReplaySubject<Object> rs = ReplaySubject.createWithSize(1);
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
for (int i = 0; i < 1000; i++) {
rs.onNext(i);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
}
rs.onCompleted();
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
}
@Test
public void testSizeAndHasAnyValueTimeBounded() {
TestScheduler ts = new TestScheduler();
ReplaySubject<Object> rs = ReplaySubject.createWithTime(1, TimeUnit.SECONDS, ts);
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
for (int i = 0; i < 1000; i++) {
rs.onNext(i);
ts.advanceTimeBy(2, TimeUnit.SECONDS);
assertEquals(1, rs.size());
assertTrue(rs.hasAnyValue());
}
rs.onCompleted();
assertEquals(0, rs.size());
assertFalse(rs.hasAnyValue());
}
@Test
public void testGetValues() {
ReplaySubject<Object> rs = ReplaySubject.create();
Object[] expected = new Object[10];
for (int i = 0; i < expected.length; i++) {
expected[i] = i;
rs.onNext(i);
assertArrayEquals(Arrays.copyOf(expected, i + 1), rs.getValues());
}
rs.onCompleted();
assertArrayEquals(expected, rs.getValues());
}
@Test
public void testGetValuesUnbounded() {
ReplaySubject<Object> rs = ReplaySubject.createUnbounded();
Object[] expected = new Object[10];
for (int i = 0; i < expected.length; i++) {
expected[i] = i;
rs.onNext(i);
assertArrayEquals(Arrays.copyOf(expected, i + 1), rs.getValues());
}
rs.onCompleted();
assertArrayEquals(expected, rs.getValues());
}
}