src/test/java/io/reactivex/rxjava4/single/SingleTest.java - 4.x - githubmirror/RxJava

src/test/java/io/reactivex/rxjava4/single/SingleTest.java
512 строк16 KB
David Karnok
4.x: Convert from JUnit 4 to JUnit 6 (#8202)
30 июн 2026, 12:01
30 июн 2026, 12:01531388f
/*
 * Copyright (c) 2016-present, RxJava Contributors.
 *
 * 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 io.reactivex.rxjava4.single;

import static org.junit.jupiter.api.Assertions.*;

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

import org.junit.jupiter.api.Test;

import io.reactivex.rxjava4.core.*;
import io.reactivex.rxjava4.core.Observable;
import io.reactivex.rxjava4.disposables.*;
import io.reactivex.rxjava4.exceptions.TestException;
import io.reactivex.rxjava4.functions.Function;
import io.reactivex.rxjava4.internal.operators.single.SingleInternalHelper;
import io.reactivex.rxjava4.schedulers.Schedulers;
import io.reactivex.rxjava4.subscribers.TestSubscriber;
import io.reactivex.rxjava4.testsupport.*;

public class SingleTest extends RxJavaTest {

    @Test
    public void helloWorld() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single.just("Hello World!").toFlowable().subscribe(ts);
        ts.assertValueSequence(List.of("Hello World!"));
    }

    @Test
    public void helloWorld2() {
        final AtomicReference<String> v = new AtomicReference<>();
        Single.just("Hello World!")
        .subscribe(new SingleObserver<>() /* NFI */ {

            @Override
            public void onSubscribe(Disposable d) {

            }

            @Override
            public void onSuccess(String value) {
                v.set(value);
            }

            @Override
            public void onError(Throwable error) {

            }

        });
        assertEquals("Hello World!", v.get());
    }

    @Test
    public void map() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single.just("A")
                .map(s -> s + "B")
                .toFlowable().subscribe(ts);
        ts.assertValueSequence(List.of("AB"));
    }

    @Test
    public void zip() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single<String> a = Single.just("A");
        Single<String> b = Single.just("B");

        Single.zip(a, b, (a1, b1) -> a1 + b1)
        .toFlowable().subscribe(ts);
        ts.assertValueSequence(List.of("AB"));
    }

    @Test
    public void zipWith() {
        TestSubscriber<String> ts = new TestSubscriber<>();

        Single.just("A").zipWith(Single.just("B"), (a1, b1) -> a1 + b1)
        .toFlowable().subscribe(ts);
        ts.assertValueSequence(List.of("AB"));
    }

    @Test
    public void merge() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single<String> a = Single.just("A");
        Single<String> b = Single.just("B");

        Single.mergeArray(a, b).subscribe(ts);
        ts.assertValueSequence(Arrays.asList("A", "B"));
    }

    @Test
    public void mergeWith() {
        TestSubscriber<String> ts = new TestSubscriber<>();

        Single.just("A").mergeWith(Single.just("B")).subscribe(ts);
        ts.assertValueSequence(Arrays.asList("A", "B"));
    }

    @Test
    public void createSuccess() {
        TestSubscriber<Object> ts = new TestSubscriber<>();

        Single.unsafeCreate(observer -> {
            observer.onSubscribe(Disposable.empty());
            observer.onSuccess("Hello");
        }).toFlowable().subscribe(ts);

        ts.assertValueSequence(List.of("Hello"));
    }

    @Test
    public void createError() {
        TestSubscriberEx<Object> ts = new TestSubscriberEx<>();
        Single.unsafeCreate(observer -> {
            observer.onSubscribe(Disposable.empty());
            observer.onError(new RuntimeException("fail"));
        }).toFlowable().subscribe(ts);

        ts.assertError(RuntimeException.class);
        ts.assertErrorMessage("fail");
    }

    @Test
    public void async() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single.just("Hello")
                .subscribeOn(Schedulers.cached())
                .map(v -> {
                    System.out.println("SubscribeOn Thread: " + Thread.currentThread());
                    return v;
                })
                .observeOn(Schedulers.computation())
                .map(v -> {
                    System.out.println("ObserveOn Thread: " + Thread.currentThread());
                    return v;
                })
                .toFlowable().subscribe(ts);
        ts.awaitDone(5, TimeUnit.SECONDS);
        ts.assertValueSequence(List.of("Hello"));
    }

    @Test
    public void flatMap() throws InterruptedException {
        TestSubscriberEx<String> ts = new TestSubscriberEx<>();
        Single.just("Hello").flatMap((Function<String, Single<String>>) s -> Single.just(s + " World!").subscribeOn(Schedulers.computation())
        ).toFlowable().subscribe(ts);
        if (!ts.await(5, TimeUnit.SECONDS)) {
            ts.cancel();
            fail("TestSubscriber timed out.");
        }
        ts.assertValueSequence(List.of("Hello World!"));
    }

    @Test
    public void timeout() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single<String> s1 = Single.<String>unsafeCreate(observer -> {
            observer.onSubscribe(Disposable.empty());
            try {
                Thread.sleep(5000);
            } catch (InterruptedException e) {
                // ignore as we expect this for the test
            }
            observer.onSuccess("success");
        }).subscribeOn(Schedulers.cached());

        s1.timeout(100, TimeUnit.MILLISECONDS).toFlowable().subscribe(ts);

        ts.awaitDone(5, TimeUnit.SECONDS);
        ts.assertError(TimeoutException.class);
    }

    @Test
    public void timeoutWithFallback() {
        TestSubscriber<String> ts = new TestSubscriber<>();
        Single<String> s1 = Single.<String>unsafeCreate(observer -> {
            observer.onSubscribe(Disposable.empty());
                try {
                    Thread.sleep(5000);
                } catch (InterruptedException e) {
                    // ignore as we expect this for the test
                }
                observer.onSuccess("success");
        }).subscribeOn(Schedulers.cached());

        s1.timeout(100, TimeUnit.MILLISECONDS, Single.just("hello")).toFlowable().subscribe(ts);

        ts.awaitDone(5, TimeUnit.SECONDS);
        ts.assertNoErrors();
        ts.assertValue("hello");
    }

    @Test
    public void unsubscribe() throws InterruptedException {
        TestSubscriber<String> ts = new TestSubscriber<>();
        final AtomicBoolean unsubscribed = new AtomicBoolean();
        final AtomicBoolean interrupted = new AtomicBoolean();
        final CountDownLatch latch = new CountDownLatch(2);

        Single<String> s1 = Single.<String>unsafeCreate(observer -> {
            SerialDisposable sd = new SerialDisposable();
            observer.onSubscribe(sd);
            final Thread t = new Thread(() -> {
                try {
                    Thread.sleep(5000);
                    observer.onSuccess("success");
                } catch (InterruptedException e) {
                    interrupted.set(true);
                    latch.countDown();
                }
            });
            sd.replace(Disposable.fromRunnable(() -> {
                unsubscribed.set(true);
                t.interrupt();
                latch.countDown();
            }));
            t.start();
        });

        s1.toFlowable().subscribe(ts);

        Thread.sleep(100);

        ts.cancel();

        if (latch.await(1000, TimeUnit.MILLISECONDS)) {
            assertTrue(unsubscribed.get());
            assertTrue(interrupted.get());
        } else {
            fail("timed out waiting for latch");
        }
    }

    /**
     * Assert that unsubscribe propagates when passing in a SingleObserver and not a Subscriber.
     * @throws InterruptedException if the test is interrupted
     */
    @Test
    public void unsubscribe2() throws InterruptedException {
        final SerialDisposable sd = new SerialDisposable();
        var ts = new SingleObserver<String>() /* NFI */ {

            @Override
            public void onSubscribe(Disposable d) {
                sd.replace(d);
            }

            @Override
            public void onSuccess(String value) {
                // not interested in value
            }

            @Override
            public void onError(Throwable error) {
                // not interested in value
            }

        };
        final AtomicBoolean unsubscribed = new AtomicBoolean();
        final AtomicBoolean interrupted = new AtomicBoolean();
        final CountDownLatch latch = new CountDownLatch(2);

        Single<String> s1 = Single.unsafeCreate(observer -> {
            SerialDisposable sd1 = new SerialDisposable();
            observer.onSubscribe(sd1);
            final Thread t = new Thread(() -> {
                try {
                    Thread.sleep(5000);
                    observer.onSuccess("success");
                } catch (InterruptedException e) {
                    interrupted.set(true);
                    latch.countDown();
                }
            });
            sd1.replace(Disposable.fromRunnable(() -> {
                unsubscribed.set(true);
                t.interrupt();
                latch.countDown();
            }));
            t.start();

        });

        s1.subscribe(ts);

        Thread.sleep(100);

        sd.dispose();

        if (latch.await(1000, TimeUnit.MILLISECONDS)) {
            assertTrue(unsubscribed.get());
            assertTrue(interrupted.get());
        } else {
            fail("timed out waiting for latch");
        }
    }

    /**
     * Assert that unsubscribe propagates when passing in a SingleObserver and not a Subscriber.
     * @throws InterruptedException if the test is interrupted
     */
    @Test
    public void unsubscribeViaReturnedSubscription() throws InterruptedException {
        final AtomicBoolean unsubscribed = new AtomicBoolean();
        final AtomicBoolean interrupted = new AtomicBoolean();
        final CountDownLatch latch = new CountDownLatch(2);

        Single<String> s1 = Single.unsafeCreate(observer -> {
            SerialDisposable sd = new SerialDisposable();
            observer.onSubscribe(sd);
            final Thread t = new Thread(() -> {
                try {
                    Thread.sleep(5000);
                    observer.onSuccess("success");
                } catch (InterruptedException e) {
                    interrupted.set(true);
                    latch.countDown();
                }
            });
            sd.replace(Disposable.fromRunnable(() -> {
                unsubscribed.set(true);
                t.interrupt();
                latch.countDown();
            }));
            t.start();

        });

        Disposable subscription = s1.subscribe();

        Thread.sleep(100);

        subscription.dispose();

        if (latch.await(1000, TimeUnit.MILLISECONDS)) {
            assertTrue(unsubscribed.get());
            assertTrue(interrupted.get());
        } else {
            fail("timed out waiting for latch");
        }
    }

    @Test
    public void backpressureAsObservable() {
        Single<String> s = Single.unsafeCreate(t -> {
            t.onSubscribe(Disposable.empty());
            t.onSuccess("hello");
        });

        TestSubscriber<String> ts = new TestSubscriber<>(0L);

        s.toFlowable().subscribe(ts);

        ts.assertNoValues();

        ts.request(1);

        ts.assertValue("hello");
    }

    @Test
    public void toObservable() {
        Flowable<String> a = Single.just("a").toFlowable();
        TestSubscriber<String> ts = new TestSubscriber<>();
        a.subscribe(ts);
        ts.assertValue("a");
        ts.assertNoErrors();
        ts.assertComplete();
    }

    @Test
    public void doOnEventNullEvent() {
        assertThrows(NullPointerException.class, () -> {
            Single.just(1).doOnEvent(null);
        });
    }

    @Test
    public void doOnEventComplete() {
        final AtomicInteger atomicInteger = new AtomicInteger(0);

        Single.just(1).doOnEvent((integer, _) -> {
            if (integer != null) {
                atomicInteger.incrementAndGet();
            }
        }).subscribe();

        assertEquals(1, atomicInteger.get());
    }

    @Test
    public void doOnEventError() {
        final AtomicInteger atomicInteger = new AtomicInteger(0);

        Single.error(new RuntimeException()).doOnEvent((_, throwable) -> {
            if (throwable != null) {
                atomicInteger.incrementAndGet();
            }
        }).subscribe();

        assertEquals(1, atomicInteger.get());
    }

    @Test
    public void toFuture() throws Exception {
        assertEquals(1, Single.just(1).toFuture().get().intValue());
    }

    @Test
    public void toFutureThrows() throws Exception {
        try {
            Single.error(new TestException()).toFuture().get();
        } catch (ExecutionException ex) {
            assertTrue(ex.getCause() instanceof TestException, ex.toString());
        }
    }

    @Test
    public void toFlowableIterableRemove() {
        assertThrows(UnsupportedOperationException.class, () -> {
            Iterable<? extends Flowable<Integer>> f = SingleInternalHelper.iterableToFlowable(Collections.singletonList(Single.just(1)));

            Iterator<? extends Flowable<Integer>> iterator = f.iterator();
            iterator.next();
            iterator.remove();
        });
    }

    @Test
    public void zipIterableObject() {
        final List<Single<Integer>> singles = Arrays.asList(Single.just(1), Single.just(4));
        Single.zip(singles, (Function<Object[], Object>) o -> {
            int sum = 0;
            for (Object i : o) {
                sum += (Integer) i;
            }
            return sum;
        }).test().assertResult(5);
    }

    @Test
    public void to() {
        Single.just(1).to(Single::toFlowable)
        .test()
        .assertResult(1);
    }

    @Test
    public void fromObservableNull() {
        assertThrows(NullPointerException.class, () -> {
            Single.fromObservable(null);
        });
    }

    @Test
    public void fromObservableEmpty() {
        Single.fromObservable(Observable.empty())
            .test()
            .assertFailure(NoSuchElementException.class);
    }

    @Test
    public void fromObservableMoreThan1Elements() {
        Single.fromObservable(Observable.just(1, 2))
        .to(TestHelper.<Integer>testConsumer())
            .assertFailure(IllegalArgumentException.class)
            .assertErrorMessage("Sequence contains more than one element!");
    }

    @Test
    public void fromObservableOneElement() {
        Single.fromObservable(Observable.just(1))
            .test()
            .assertResult(1);
    }

    @Test
    public void fromObservableError() {
        Single.fromObservable(Observable.error(new RuntimeException("some error")))
        .to(TestHelper.testConsumer())
            .assertFailure(RuntimeException.class)
            .assertErrorMessage("some error");
    }

    @Test
    public void implementationThrows() {
        assertThrows(NullPointerException.class, () -> {
            new Single<Integer>() /* NFI */ {
                @Override
                protected void subscribeActual(SingleObserver<? super Integer> observer) {
                    throw new NullPointerException();
                }
            }.test();
        });
    }
}