guava

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/*
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 * Copyright (C) 2015 The Guava Authors
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 * http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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package com.google.common.collect.testing.testers;
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import static com.google.common.collect.testing.features.CollectionFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION;
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import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ITERATOR_REMOVE;
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import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
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import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
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import static com.google.common.collect.testing.features.CollectionSize.ZERO;
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import com.google.common.annotations.GwtCompatible;
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import com.google.common.collect.testing.AbstractCollectionTester;
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import com.google.common.collect.testing.features.CollectionFeature;
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import com.google.common.collect.testing.features.CollectionSize;
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import java.util.Collection;
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import java.util.ConcurrentModificationException;
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import java.util.Iterator;
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import java.util.function.Predicate;
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import org.junit.Ignore;
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/**
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 * A generic JUnit test which tests {@link Collection#removeIf}. Can't be invoked directly; please
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 * see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
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 *
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 * @author Louis Wasserman
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 */
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@GwtCompatible
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@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
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public class CollectionRemoveIfTester<E> extends AbstractCollectionTester<E> {
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  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
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  public void testRemoveIf_alwaysFalse() {
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    assertFalse("removeIf(x -> false) should return false", collection.removeIf(x -> false));
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    expectUnchanged();
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  }
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  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
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  @CollectionSize.Require(absent = ZERO)
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  public void testRemoveIf_sometimesTrue() {
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    assertTrue(
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        "removeIf(isEqual(present)) should return true",
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        collection.removeIf(Predicate.isEqual(samples.e0())));
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    expectMissing(samples.e0());
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  }
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  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
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  @CollectionSize.Require(absent = ZERO)
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  public void testRemoveIf_allPresent() {
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    assertTrue("removeIf(x -> true) should return true", collection.removeIf(x -> true));
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    expectContents();
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  }
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  @CollectionFeature.Require({SUPPORTS_ITERATOR_REMOVE, FAILS_FAST_ON_CONCURRENT_MODIFICATION})
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  @CollectionSize.Require(SEVERAL)
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  public void testRemoveIfSomeMatchesConcurrentWithIteration() {
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    try {
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      Iterator<E> iterator = collection.iterator();
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      assertTrue(collection.removeIf(Predicate.isEqual(samples.e0())));
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      iterator.next();
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      fail("Expected ConcurrentModificationException");
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    } catch (ConcurrentModificationException expected) {
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      // success
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    }
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  }
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  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
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  @CollectionSize.Require(ZERO)
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  public void testRemoveIf_unsupportedEmptyCollection() {
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    try {
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      assertFalse(
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          "removeIf(Predicate) should return false or throw " + "UnsupportedOperationException",
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          collection.removeIf(
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              x -> {
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                throw new AssertionError("predicate should never be called");
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              }));
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    } catch (UnsupportedOperationException tolerated) {
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    }
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    expectUnchanged();
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  }
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  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
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  @CollectionSize.Require(absent = ZERO)
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  public void testRemoveIf_alwaysTrueUnsupported() {
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    try {
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      collection.removeIf(x -> true);
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      fail("removeIf(x -> true) should throw " + "UnsupportedOperationException");
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    } catch (UnsupportedOperationException expected) {
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    }
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    expectUnchanged();
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    assertTrue(collection.contains(samples.e0()));
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  }
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}
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