MultimapAsMapGetTester.java

/*
 * Copyright (C) 2013 The Guava 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 com.google.common.collect.testing.google;

import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUE_QUERIES;
import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_PUT;
import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
import static com.google.common.truth.Truth.assertThat;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Multimap;
import com.google.common.collect.testing.Helpers;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;

import java.util.Collection;

/**
 * Tests for {@code Multimap.asMap().get(Object)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
public class MultimapAsMapGetTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  
  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testPropagatesRemoveToMultimap() {
    resetContainer(
        Helpers.mapEntry(sampleKeys().e0, sampleValues().e0),
        Helpers.mapEntry(sampleKeys().e0, sampleValues().e3),
        Helpers.mapEntry(sampleKeys().e0, sampleValues().e2));
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    assertTrue(result.remove(sampleValues().e0));
    assertFalse(multimap().containsEntry(sampleKeys().e0, sampleValues().e0));
    assertEquals(2, multimap().size());
  }
  
  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testPropagatesRemoveLastElementToMultimap() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    assertTrue(result.remove(sampleValues().e0));
    assertGet(sampleKeys().e0);
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testPropagatesClearToMultimap() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    result.clear();
    assertGet(sampleKeys().e0);
    assertThat(result).isEmpty();
  }
  
  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  public void testAddNullValue() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    assertTrue(result.add(null));
    assertTrue(multimap().containsEntry(sampleKeys().e0, null));
  }
  
  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUE_QUERIES})
  public void testRemoveNullValue() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    assertFalse(result.remove(null));
  }
  
  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  public void testAddNullValueUnsupported() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    try {
      result.add(null);
      fail("Expected NullPointerException");
    } catch (NullPointerException expected) {}
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_PUT)
  public void testPropagatesAddToMultimap() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    result.add(sampleValues().e3);
    assertThat(multimap().get(sampleKeys().e0))
        .has().exactly(sampleValues().e0, sampleValues().e3);
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require({ SUPPORTS_REMOVE, SUPPORTS_PUT })
  public void testPropagatesRemoveThenAddToMultimap() {
    int oldSize = getNumElements();

    K k0 = sampleKeys().e0;
    V v0 = sampleValues().e0;

    Collection<V> result = multimap().asMap().get(k0);
    assertTrue(result.remove(v0));

    assertFalse(multimap().containsKey(k0));
    assertFalse(multimap().containsEntry(k0, v0));
    assertThat(result).isEmpty();

    V v1 = sampleValues().e1;
    V v2 = sampleValues().e2;

    assertTrue(result.add(v1));
    assertTrue(result.add(v2));

    assertThat(result).has().exactly(v1, v2);
    assertThat(multimap().get(k0)).has().exactly(v1, v2);
    assertTrue(multimap().containsKey(k0));
    assertFalse(multimap().containsEntry(k0, v0));
    assertTrue(multimap().containsEntry(k0, v2));
    assertEquals(oldSize + 1, multimap().size());
  }
  
  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testReflectsMultimapRemove() {
    Collection<V> result = multimap().asMap().get(sampleKeys().e0);
    multimap().removeAll(sampleKeys().e0);
    assertThat(result).isEmpty();
  }
}