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Java 17, JUnit 5.9.3 and Mockito 5.3.1 mocking interface default methods does not work
/*
* Copyright 2011-Present Author or Authors.
*
* 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 examples;
import static org.assertj.core.api.Assertions.assertThat;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.Mockito.doCallRealMethod;
import static org.mockito.Mockito.doReturn;
import static org.mockito.Mockito.mock;
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.List;
import org.junit.jupiter.api.Test;
/**
* Unit Tests for JUnit 5 and Mockito 5.3.x mocking default methods on a interface.
*
* @author John Blum
* @see org.junit.jupiter.api.Test
* @see org.mockito.Mockito
* @since 1.0.0
*/
public class MockingInterfaceDefaultMethodsUnitTests {
@Test
@SuppressWarnings("unchecked")
public void cacheContainsAllKeysReturnsTrue() {
Cache<String, Object> mockCache = mock(Cache.class);
doReturn(true).when(mockCache).contains(any());
doCallRealMethod().when(mockCache).containsAll(any());
assertThat(mockCache.containsAll("KeyOne", "KeyTwo")).isTrue();
verify(mockCache, times(1)).containsAll(eq("KeyOne"), eq("KeyTwo"));
Arrays.asList("KeyOne", "KeyTwo").forEach(key ->
verify(mockCache, times(1)).contains(eq(key)));
verifyNoMoreInteractions(mockCache);
}
@Test
@SuppressWarnings("unchecked")
public void listContainsAllElementsReturnsTrue() {
ExtList<Object> mockList = mock(ExtList.class);
doReturn(true).when(mockList).contains(any());
doCallRealMethod().when(mockList).containsAll(any(Object[].class));
assertThat(mockList.containsAll("ONE", "TWO")).isTrue();
verify(mockList, times(1)).containsAll(eq("ONE"), eq("TWO"));
Arrays.asList("ONE", "TWO").forEach(element ->
verify(mockList, times(1)).contains(eq(element)));
verifyNoMoreInteractions(mockList);
}
@SuppressWarnings("unused")
interface Cache<KEY extends Comparable<KEY>, VALUE> {
boolean contains(KEY key);
@SuppressWarnings("unchecked")
default boolean containsAll(KEY... keys) {
return Arrays.stream(keys).allMatch(this::contains);
}
}
interface ExtList<T> extends List<T> {
@SuppressWarnings("unchecked")
default boolean containsAll(T... elements) {
return Arrays.stream(elements).allMatch(this::contains);
}
}
}
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