CompletableTest.java

/**
 * 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;

import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;

import org.junit.*;

import rx.Completable.*;
import rx.Observable.OnSubscribe;
import rx.exceptions.*;
import rx.functions.*;
import rx.observers.TestSubscriber;
import rx.plugins.RxJavaPlugins;
import rx.schedulers.*;
import rx.subjects.PublishSubject;
import rx.subscriptions.*;

import static org.mockito.Mockito.*;
import static org.junit.Assert.*;

/**
 * Test Completable methods and operators.
 */
public class CompletableTest {
    /**
     * Iterable that returns an Iterator that throws in its hasNext method.
     */
    static final class IterableIteratorNextThrows implements Iterable<Completable> {
        @Override
        public Iterator<Completable> iterator() {
            return new Iterator<Completable>() {
                @Override
                public boolean hasNext() {
                    return true;
                }
                
                @Override
                public Completable next() {
                    throw new TestException();
                }
                
                @Override
                public void remove() {
                    throw new UnsupportedOperationException();
                }
            };
        }
    }

    /**
     * Iterable that returns an Iterator that throws in its next method.
     */
    static final class IterableIteratorHasNextThrows implements Iterable<Completable> {
        @Override
        public Iterator<Completable> iterator() {
            return new Iterator<Completable>() {
                @Override
                public boolean hasNext() {
                    throw new TestException();
                }
                
                @Override
                public Completable next() {
                    return null;
                }
                

                @Override
                public void remove() {
                    throw new UnsupportedOperationException();
                }
            };
        }
    }

    /**
     * A class containing a completable instance and counts the number of subscribers.
     */
    static final class NormalCompletable extends AtomicInteger {
        /** */
        private static final long serialVersionUID = 7192337844700923752L;
        
        public final Completable completable = Completable.create(new CompletableOnSubscribe() {
            @Override
            public void call(CompletableSubscriber s) {
                getAndIncrement();
                s.onSubscribe(Subscriptions.unsubscribed());
                s.onCompleted();
            }
        });
        
        /**
         * Asserts the given number of subscriptions happened.
         * @param n the expected number of subscriptions
         */
        public void assertSubscriptions(int n) {
            Assert.assertEquals(n, get());
        }
    }

    /**
     * A class containing a completable instance that emits a TestException and counts
     * the number of subscribers.
     */
    static final class ErrorCompletable extends AtomicInteger {
        /** */
        private static final long serialVersionUID = 7192337844700923752L;
        
        public final Completable completable = Completable.create(new CompletableOnSubscribe() {
            @Override
            public void call(CompletableSubscriber s) {
                getAndIncrement();
                s.onSubscribe(Subscriptions.unsubscribed());
                s.onError(new TestException());
            }
        });
        
        /**
         * Asserts the given number of subscriptions happened.
         * @param n the expected number of subscriptions
         */
        public void assertSubscriptions(int n) {
            Assert.assertEquals(n, get());
        }
    }

    /** A normal Completable object. */
    final NormalCompletable normal = new NormalCompletable();

    /** An error Completable object. */
    final ErrorCompletable error = new ErrorCompletable();

    @Test(timeout = 1000)
    public void complete() {
        Completable c = Completable.complete();
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void concatNull() {
        Completable.concat((Completable[])null);
    }
    
    @Test(timeout = 1000)
    public void concatEmpty() {
        Completable c = Completable.concat();
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatSingleSource() {
        Completable c = Completable.concat(normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatSingleSourceThrows() {
        Completable c = Completable.concat(error.completable);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatMultipleSources() {
        Completable c = Completable.concat(normal.completable, normal.completable, normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatMultipleOneThrows() {
        Completable c = Completable.concat(normal.completable, error.completable, normal.completable);
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void concatMultipleOneIsNull() {
        Completable c = Completable.concat(normal.completable, null);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatIterableEmpty() {
        Completable c = Completable.concat(Collections.<Completable>emptyList());
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void concatIterableNull() {
        Completable.concat((Iterable<Completable>)null);
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void concatIterableIteratorNull() {
        Completable c = Completable.concat(new Iterable<Completable>() {
            @Override
            public Iterator<Completable> iterator() {
                return null;
            }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void concatIterableWithNull() {
        Completable c = Completable.concat(Arrays.asList(normal.completable, (Completable)null));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatIterableSingle() {
        Completable c = Completable.concat(Collections.singleton(normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000)
    public void concatIterableMany() {
        Completable c = Completable.concat(Arrays.asList(normal.completable, normal.completable, normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatIterableOneThrows() {
        Completable c = Completable.concat(Collections.singleton(error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatIterableManyOneThrows() {
        Completable c = Completable.concat(Arrays.asList(normal.completable, error.completable));
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void concatIterableIterableThrows() {
        Completable c = Completable.concat(new Iterable<Completable>() {
            @Override
            public Iterator<Completable> iterator() {
                throw new TestException();
            }
        });
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void concatIterableIteratorHasNextThrows() {
        Completable c = Completable.concat(new IterableIteratorHasNextThrows());
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void concatIterableIteratorNextThrows() {
        Completable c = Completable.concat(new IterableIteratorNextThrows());
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatObservableEmpty() {
        Completable c = Completable.concat(Observable.<Completable>empty());
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatObservableError() {
        Completable c = Completable.concat(Observable.<Completable>error(new TestException()));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatObservableSingle() {
        Completable c = Completable.concat(Observable.just(normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatObservableSingleThrows() {
        Completable c = Completable.concat(Observable.just(error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatObservableMany() {
        Completable c = Completable.concat(Observable.just(normal.completable).repeat(3));
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void concatObservableManyOneThrows() {
        Completable c = Completable.concat(Observable.just(normal.completable, error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void concatObservablePrefetch() {
        final List<Long> requested = new ArrayList<Long>();
        Observable<Completable> cs = Observable
                .just(normal.completable)
                .repeat(10)
                .doOnRequest(new Action1<Long>() {
                    @Override
                    public void call(Long v) {
                        requested.add(v);
                    }
                });
        
        Completable c = Completable.concat(cs, 5);
        
        c.await();
        
        // FIXME this request pattern looks odd because all 10 completions trigger 1 requests
        Assert.assertEquals(Arrays.asList(5L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), requested);
    }
    
    @Test
    public void andThen() {
        TestSubscriber<String> ts = new TestSubscriber<String>(0);
        Completable.complete().andThen(Observable.just("foo")).subscribe(ts);
        ts.requestMore(1);
        ts.assertValue("foo");
        ts.assertCompleted();
        ts.assertNoErrors();
    }
    
    @Test
    public void andThenNever() {
        TestSubscriber<String> ts = new TestSubscriber<String>(0);
        Completable.never().andThen(Observable.just("foo")).subscribe(ts);
        ts.requestMore(1);
        ts.assertNoValues();
        ts.assertNoTerminalEvent();
    }
    
    @Test
    public void andThenError() {
        TestSubscriber<String> ts = new TestSubscriber<String>(0);
        final AtomicBoolean hasRun = new AtomicBoolean(false);
        final Exception e = new Exception();
        Completable.create(new CompletableOnSubscribe() {
                @Override
                public void call(CompletableSubscriber cs) {
                    cs.onError(e);
                }
            })
            .andThen(Observable.<String>create(new OnSubscribe<String>() {
                @Override
                public void call(Subscriber<? super String> s) {
                    hasRun.set(true);
                    s.onNext("foo");
                    s.onCompleted();
                }
            }))
            .subscribe(ts);
        ts.assertNoValues();
        ts.assertError(e);
        Assert.assertFalse("Should not have subscribed to observable when completable errors", hasRun.get());
    }
    
    @Test
    public void andThenSubscribeOn() {
        TestSubscriber<String> ts = new TestSubscriber<String>(0);
        TestScheduler scheduler = new TestScheduler();
        Completable.complete().andThen(Observable.just("foo").delay(1, TimeUnit.SECONDS, scheduler)).subscribe(ts);
        ts.requestMore(1);
        ts.assertNoValues();
        ts.assertNoTerminalEvent();
        scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
        ts.assertValue("foo");
        ts.assertCompleted();
        ts.assertNoErrors();
    }
    
    @Test(expected = NullPointerException.class)
    public void createNull() {
        Completable.create(null);
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void createOnSubscribeThrowsNPE() {
        Completable c = Completable.create(new CompletableOnSubscribe() {
            @Override
            public void call(CompletableSubscriber s) { throw new NullPointerException(); }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void createOnSubscribeThrowsRuntimeException() {
        try {
            Completable c = Completable.create(new CompletableOnSubscribe() {
                @Override
                public void call(CompletableSubscriber s) {
                    throw new TestException();
                }
            });
            
            c.await();
            
            Assert.fail("Did not throw exception");
        } catch (NullPointerException ex) {
            if (!(ex.getCause() instanceof TestException)) {
                ex.printStackTrace();
                Assert.fail("Did not wrap the TestException but it returned: " + ex);
            }
        }
    }
    
    @Test(timeout = 1000)
    public void defer() {
        Completable c = Completable.defer(new Func0<Completable>() {
            @Override
            public Completable call() {
                return normal.completable;
            }
        });
        
        normal.assertSubscriptions(0);
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(expected = NullPointerException.class)
    public void deferNull() {
        Completable.defer(null);
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void deferReturnsNull() {
        Completable c = Completable.defer(new Func0<Completable>() {
            @Override
            public Completable call() {
                return null;
            }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void deferFunctionThrows() {
        Completable c = Completable.defer(new Func0<Completable>() {
            @Override
            public Completable call() { throw new TestException(); }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void deferErrorSource() {
        Completable c = Completable.defer(new Func0<Completable>() {
            @Override
            public Completable call() {
                return error.completable;
            }
        });
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void errorNull() {
        Completable.error((Throwable)null);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void errorNormal() {
        Completable c = Completable.error(new TestException());
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void fromCallableNull() {
        Completable.fromCallable(null);
    }
    
    @Test(timeout = 1000)
    public void fromCallableNormal() {
        final AtomicInteger calls = new AtomicInteger();
        
        Completable c = Completable.fromCallable(new Callable<Object>() {
            @Override
            public Object call() throws Exception {
                return calls.getAndIncrement();
            }
        });
        
        c.await();
        
        Assert.assertEquals(1, calls.get());
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void fromCallableThrows() {
        Completable c = Completable.fromCallable(new Callable<Object>() {
            @Override
            public Object call() throws Exception { throw new TestException(); }
        });
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void fromObservableNull() {
        Completable.fromObservable(null);
    }
    
    @Test(timeout = 1000)
    public void fromObservableEmpty() {
        Completable c = Completable.fromObservable(Observable.empty());
        
        c.await();
    }

    @Test(timeout = 5000)
    public void fromObservableSome() {
        for (int n = 1; n < 10000; n *= 10) {
            Completable c = Completable.fromObservable(Observable.range(1, n));
            
            c.await();
        }
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void fromObservableError() {
        Completable c = Completable.fromObservable(Observable.error(new TestException()));
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void fromFutureNull() {
        Completable.fromFuture(null);
    }
    
    @Test(timeout = 1000)
    public void fromFutureNormal() {
        ExecutorService exec = Executors.newSingleThreadExecutor();
        
        try {
            Completable c = Completable.fromFuture(exec.submit(new Runnable() {
                @Override
                public void run() { 
                    // no action
                }
            }));
            
            c.await();
        } finally {
            exec.shutdown();
        }
    }
    
    @Test(timeout = 1000)
    public void fromFutureThrows() {
        ExecutorService exec = Executors.newSingleThreadExecutor();
        
        Completable c = Completable.fromFuture(exec.submit(new Runnable() {
            @Override
            public void run() { 
                throw new TestException();
            }
        }));
        
        try {
            c.await();
            Assert.fail("Failed to throw Exception");
        } catch (RuntimeException ex) {
            if (!((ex.getCause() instanceof ExecutionException) && (ex.getCause().getCause() instanceof TestException))) {
                ex.printStackTrace();
                Assert.fail("Wrong exception received");
            }
        } finally {
            exec.shutdown();
        }
    }
    
    @Test(expected = NullPointerException.class)
    public void fromActionNull() {
        Completable.fromAction(null);
    }
    
    @Test(timeout = 1000)
    public void fromActionNormal() {
        final AtomicInteger calls = new AtomicInteger();
        
        Completable c = Completable.fromAction(new Action0() {
            @Override
            public void call() {
                calls.getAndIncrement();
            }
        });
        
        c.await();
        
        Assert.assertEquals(1, calls.get());
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void fromActionThrows() {
        Completable c = Completable.fromAction(new Action0() {
            @Override
            public void call() { throw new TestException(); }
        });
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void fromSingleNull() {
        Completable.fromSingle(null);
    }
    
    @Test(timeout = 1000)
    public void fromSingleNormal() {
        Completable c = Completable.fromSingle(Single.just(1));
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void fromSingleThrows() {
        Completable c = Completable.fromSingle(Single.error(new TestException()));
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void mergeNull() {
        Completable.merge((Completable[])null);
    }
    
    @Test(timeout = 1000)
    public void mergeEmpty() {
        Completable c = Completable.merge();
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeSingleSource() {
        Completable c = Completable.merge(normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeSingleSourceThrows() {
        Completable c = Completable.merge(error.completable);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeMultipleSources() {
        Completable c = Completable.merge(normal.completable, normal.completable, normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeMultipleOneThrows() {
        Completable c = Completable.merge(normal.completable, error.completable, normal.completable);
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeMultipleOneIsNull() {
        Completable c = Completable.merge(normal.completable, null);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeIterableEmpty() {
        Completable c = Completable.merge(Collections.<Completable>emptyList());
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void mergeIterableNull() {
        Completable.merge((Iterable<Completable>)null);
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeIterableIteratorNull() {
        Completable c = Completable.merge(new Iterable<Completable>() {
            @Override
            public Iterator<Completable> iterator() {
                return null;
            }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeIterableWithNull() {
        Completable c = Completable.merge(Arrays.asList(normal.completable, (Completable)null));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeIterableSingle() {
        Completable c = Completable.merge(Collections.singleton(normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000)
    public void mergeIterableMany() {
        Completable c = Completable.merge(Arrays.asList(normal.completable, normal.completable, normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeIterableOneThrows() {
        Completable c = Completable.merge(Collections.singleton(error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeIterableManyOneThrows() {
        Completable c = Completable.merge(Arrays.asList(normal.completable, error.completable));
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void mergeIterableIterableThrows() {
        Completable c = Completable.merge(new Iterable<Completable>() {
            @Override
            public Iterator<Completable> iterator() {
                throw new TestException();
            }
        });
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void mergeIterableIteratorHasNextThrows() {
        Completable c = Completable.merge(new IterableIteratorHasNextThrows());
        
        c.await();
    }
    
    @Test(expected = TestException.class)
    public void mergeIterableIteratorNextThrows() {
        Completable c = Completable.merge(new IterableIteratorNextThrows());
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeObservableEmpty() {
        Completable c = Completable.merge(Observable.<Completable>empty());
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeObservableError() {
        Completable c = Completable.merge(Observable.<Completable>error(new TestException()));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeObservableSingle() {
        Completable c = Completable.merge(Observable.just(normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeObservableSingleThrows() {
        Completable c = Completable.merge(Observable.just(error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeObservableMany() {
        Completable c = Completable.merge(Observable.just(normal.completable).repeat(3));
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeObservableManyOneThrows() {
        Completable c = Completable.merge(Observable.just(normal.completable, error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeObservableMaxConcurrent() {
        final List<Long> requested = new ArrayList<Long>();
        Observable<Completable> cs = Observable
                .just(normal.completable)
                .repeat(10)
                .doOnRequest(new Action1<Long>() {
                    @Override
                    public void call(Long v) {
                        requested.add(v);
                    }
                });
        
        Completable c = Completable.merge(cs, 5);
        
        c.await();
        
        // FIXME this request pattern looks odd because all 10 completions trigger 1 requests
        Assert.assertEquals(Arrays.asList(5L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), requested);
    }

    @Test(expected = NullPointerException.class)
    public void mergeDelayErrorNull() {
        Completable.mergeDelayError((Completable[])null);
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorEmpty() {
        Completable c = Completable.mergeDelayError();
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorSingleSource() {
        Completable c = Completable.mergeDelayError(normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeDelayErrorSingleSourceThrows() {
        Completable c = Completable.mergeDelayError(error.completable);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorMultipleSources() {
        Completable c = Completable.mergeDelayError(normal.completable, normal.completable, normal.completable);
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorMultipleOneThrows() {
        Completable c = Completable.mergeDelayError(normal.completable, error.completable, normal.completable);
        
        try {
            c.await();
        } catch (TestException ex) {
            normal.assertSubscriptions(2);
        }
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeDelayErrorMultipleOneIsNull() {
        Completable c = Completable.mergeDelayError(normal.completable, null);
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorIterableEmpty() {
        Completable c = Completable.mergeDelayError(Collections.<Completable>emptyList());
        
        c.await();
    }
    
    @Test(expected = NullPointerException.class)
    public void mergeDelayErrorIterableNull() {
        Completable.mergeDelayError((Iterable<Completable>)null);
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeDelayErrorIterableIteratorNull() {
        Completable c = Completable.mergeDelayError(new Iterable<Completable>() {
            @Override
            public Iterator<Completable> iterator() {
                return null;
            }
        });
        
        c.await();
    }
    
    @Test(timeout = 1000, expected = NullPointerException.class)
    public void mergeDelayErrorIterableWithNull() {
        Completable c = Completable.mergeDelayError(Arrays.asList(normal.completable, (Completable)null));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorIterableSingle() {
        Completable c = Completable.mergeDelayError(Collections.singleton(normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(1);
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorIterableMany() {
        Completable c = Completable.mergeDelayError(Arrays.asList(normal.completable, normal.completable, normal.completable));
        
        c.await();
        
        normal.assertSubscriptions(3);
    }
    
    @Test(timeout = 1000, expected = TestException.class)
    public void mergeDelayErrorIterableOneThrows() {
        Completable c = Completable.mergeDelayError(Collections.singleton(error.completable));
        
        c.await();
    }
    
    @Test(timeout = 1000)
    public void mergeDelayErrorIterableManyOneThrows() {