/**
* 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.internal.operators;
import static org.junit.Assert.assertEquals;
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 java.util.Arrays;
import java.util.concurrent.atomic.AtomicInteger;
import org.junit.Test;
import org.mockito.InOrder;
import rx.Observable;
import rx.Observer;
import rx.Subscriber;
import rx.functions.Func1;
import rx.internal.util.RxRingBuffer;
import rx.internal.util.UtilityFunctions;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
public class OperatorTakeLastTest {
@Test
public void testTakeLastEmpty() {
Observable<String> w = Observable.empty();
Observable<String> take = w.takeLast(2);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
take.subscribe(observer);
verify(observer, never()).onNext(any(String.class));
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testTakeLast1() {
Observable<String> w = Observable.just("one", "two", "three");
Observable<String> take = w.takeLast(2);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
InOrder inOrder = inOrder(observer);
take.subscribe(observer);
inOrder.verify(observer, times(1)).onNext("two");
inOrder.verify(observer, times(1)).onNext("three");
verify(observer, never()).onNext("one");
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testTakeLast2() {
Observable<String> w = Observable.just("one");
Observable<String> take = w.takeLast(10);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
take.subscribe(observer);
verify(observer, times(1)).onNext("one");
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testTakeLastWithZeroCount() {
Observable<String> w = Observable.just("one");
Observable<String> take = w.takeLast(0);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
take.subscribe(observer);
verify(observer, never()).onNext("one");
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testTakeLastWithNull() {
Observable<String> w = Observable.just("one", null, "three");
Observable<String> take = w.takeLast(2);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
take.subscribe(observer);
verify(observer, never()).onNext("one");
verify(observer, times(1)).onNext(null);
verify(observer, times(1)).onNext("three");
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test(expected = IndexOutOfBoundsException.class)
public void testTakeLastWithNegativeCount() {
Observable.just("one").takeLast(-1);
}
@Test
public void testBackpressure1() {
TestSubscriber<Integer> ts = new TestSubscriber<Integer>();
Observable.range(1, 100000).takeLast(1).observeOn(Schedulers.newThread()).map(newSlowProcessor()).subscribe(ts);
ts.awaitTerminalEvent();
ts.assertNoErrors();
ts.assertReceivedOnNext(Arrays.asList(100000));
}
@Test
public void testBackpressure2() {
TestSubscriber<Integer> ts = new TestSubscriber<Integer>();
Observable.range(1, 100000).takeLast(RxRingBuffer.SIZE * 4).observeOn(Schedulers.newThread()).map(newSlowProcessor()).subscribe(ts);
ts.awaitTerminalEvent();
ts.assertNoErrors();
assertEquals(RxRingBuffer.SIZE * 4, ts.getOnNextEvents().size());
}
private Func1<Integer, Integer> newSlowProcessor() {
return new Func1<Integer, Integer>() {
int c = 0;
@Override
public Integer call(Integer i) {
if (c++ < 100) {
try {
Thread.sleep(1);
} catch (InterruptedException e) {
}
}
return i;
}
};
}
@Test
public void testIssue1522() {
// https://github.com/ReactiveX/RxJava/issues/1522
assertEquals(0, Observable
.empty()
.count()
.filter(UtilityFunctions.alwaysFalse())
.toList()
.toBlocking().single().size());
}
@Test
public void testIgnoreRequest1() {
// If `takeLast` does not ignore `request` properly, StackOverflowError will be thrown.
Observable.range(0, 100000).takeLast(100000).subscribe(new Subscriber<Integer>() {
@Override
public void onStart() {
request(Long.MAX_VALUE);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Integer integer) {
request(Long.MAX_VALUE);
}
});
}
@Test
public void testIgnoreRequest2() {
// If `takeLast` does not ignore `request` properly, StackOverflowError will be thrown.
Observable.range(0, 100000).takeLast(100000).subscribe(new Subscriber<Integer>() {
@Override
public void onStart() {
request(1);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Integer integer) {
request(1);
}
});
}
@Test(timeout = 30000)
public void testIgnoreRequest3() {
// If `takeLast` does not ignore `request` properly, it will enter an infinite loop.
Observable.range(0, 100000).takeLast(100000).subscribe(new Subscriber<Integer>() {
@Override
public void onStart() {
request(1);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Integer integer) {
request(Long.MAX_VALUE);
}
});
}
@Test
public void testIgnoreRequest4() {
// If `takeLast` does not ignore `request` properly, StackOverflowError will be thrown.
Observable.range(0, 100000).takeLast(100000).subscribe(new Subscriber<Integer>() {
@Override
public void onStart() {
request(Long.MAX_VALUE);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Integer integer) {
request(1);
}
});
}
@Test
public void testUnsubscribeTakesEffectEarlyOnFastPath() {
final AtomicInteger count = new AtomicInteger();
Observable.range(0, 100000).takeLast(100000).subscribe(new Subscriber<Integer>() {
@Override
public void onStart() {
request(Long.MAX_VALUE);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Integer integer) {
count.incrementAndGet();
unsubscribe();
}
});
assertEquals(1,count.get());
}
}