OperatorFirstTest.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.internal.operators;

import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyString;
import static org.mockito.Matchers.isA;
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.MockitoAnnotations.initMocks;

import java.util.NoSuchElementException;

import org.junit.Before;
import org.junit.Test;
import org.mockito.InOrder;
import org.mockito.Mock;

import rx.Observable;
import rx.Observer;
import rx.functions.Func1;

public class OperatorFirstTest {

    @Mock
    Observer<String> w;

    private static final Func1<String, Boolean> IS_D = new Func1<String, Boolean>() {
        @Override
        public Boolean call(String value) {
            return "d".equals(value);
        }
    };

    @Before
    public void before() {
        initMocks(this);
    }

    @Test
    public void testFirstOrElseOfNone() {
        Observable<String> src = Observable.empty();
        src.firstOrDefault("default").subscribe(w);

        verify(w, times(1)).onNext(anyString());
        verify(w, times(1)).onNext("default");
        verify(w, never()).onError(any(Throwable.class));
        verify(w, times(1)).onCompleted();
    }

    @Test
    public void testFirstOrElseOfSome() {
        Observable<String> src = Observable.just("a", "b", "c");
        src.firstOrDefault("default").subscribe(w);

        verify(w, times(1)).onNext(anyString());
        verify(w, times(1)).onNext("a");
        verify(w, never()).onError(any(Throwable.class));
        verify(w, times(1)).onCompleted();
    }

    @Test
    public void testFirstOrElseWithPredicateOfNoneMatchingThePredicate() {
        Observable<String> src = Observable.just("a", "b", "c");
        src.firstOrDefault("default", IS_D).subscribe(w);

        verify(w, times(1)).onNext(anyString());
        verify(w, times(1)).onNext("default");
        verify(w, never()).onError(any(Throwable.class));
        verify(w, times(1)).onCompleted();
    }

    @Test
    public void testFirstOrElseWithPredicateOfSome() {
        Observable<String> src = Observable.just("a", "b", "c", "d", "e", "f");
        src.firstOrDefault("default", IS_D).subscribe(w);

        verify(w, times(1)).onNext(anyString());
        verify(w, times(1)).onNext("d");
        verify(w, never()).onError(any(Throwable.class));
        verify(w, times(1)).onCompleted();
    }

    @Test
    public void testFirst() {
        Observable<Integer> observable = Observable.just(1, 2, 3).first();

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(1);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstWithOneElement() {
        Observable<Integer> observable = Observable.just(1).first();

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(1);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstWithEmpty() {
        Observable<Integer> observable = Observable.<Integer> empty().first();

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onError(
                isA(NoSuchElementException.class));
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstWithPredicate() {
        Observable<Integer> observable = Observable.just(1, 2, 3, 4, 5, 6)
                .first(new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(2);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstWithPredicateAndOneElement() {
        Observable<Integer> observable = Observable.just(1, 2).first(
                new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(2);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstWithPredicateAndEmpty() {
        Observable<Integer> observable = Observable.just(1).first(
                new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });
        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onError(
                isA(NoSuchElementException.class));
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefault() {
        Observable<Integer> observable = Observable.just(1, 2, 3)
                .firstOrDefault(4);

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(1);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefaultWithOneElement() {
        Observable<Integer> observable = Observable.just(1).firstOrDefault(2);

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(1);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefaultWithEmpty() {
        Observable<Integer> observable = Observable.<Integer> empty()
                .firstOrDefault(1);

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(1);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefaultWithPredicate() {
        Observable<Integer> observable = Observable.just(1, 2, 3, 4, 5, 6)
                .firstOrDefault(8, new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(2);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefaultWithPredicateAndOneElement() {
        Observable<Integer> observable = Observable.just(1, 2).firstOrDefault(
                4, new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(2);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testFirstOrDefaultWithPredicateAndEmpty() {
        Observable<Integer> observable = Observable.just(1).firstOrDefault(2,
                new Func1<Integer, Boolean>() {

                    @Override
                    public Boolean call(Integer t1) {
                        return t1 % 2 == 0;
                    }
                });

        @SuppressWarnings("unchecked")
        Observer<Integer> observer = mock(Observer.class);
        observable.subscribe(observer);

        InOrder inOrder = inOrder(observer);
        inOrder.verify(observer, times(1)).onNext(2);
        inOrder.verify(observer, times(1)).onCompleted();
        inOrder.verifyNoMoreInteractions();
    }
}