/*
    * Copyright (C) 2008 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.testers;
  
  import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_QUERIES;
  import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
  import static com.google.common.collect.testing.features.CollectionFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION;
  import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
  import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
  import static com.google.common.collect.testing.features.CollectionSize.ZERO;
  
  import com.google.common.annotations.GwtCompatible;
  import com.google.common.collect.testing.AbstractCollectionTester;
  import com.google.common.collect.testing.MinimalCollection;
  import com.google.common.collect.testing.WrongType;
  import com.google.common.collect.testing.features.CollectionFeature;
  import com.google.common.collect.testing.features.CollectionSize;
  
  import java.util.Collections;
  import java.util.ConcurrentModificationException;
  import java.util.Iterator;
  
  /**
   * A generic JUnit test which tests {@code removeAll} operations on a
   * collection. Can't be invoked directly; please see
   * {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
   *
   * @author George van den Driessche
   * @author Chris Povirk
   */
  @SuppressWarnings("unchecked") // too many "unchecked generic array creations"
  @GwtCompatible
  public class CollectionRemoveAllTester<E> extends AbstractCollectionTester<E> {
    @CollectionFeature.Require(SUPPORTS_REMOVE)
    public void testRemoveAll_emptyCollection() {
      assertFalse("removeAll(emptyCollection) should return false",
          collection.removeAll(MinimalCollection.of()));
      expectUnchanged();
    }
  
    @CollectionFeature.Require(SUPPORTS_REMOVE)
    public void testRemoveAll_nonePresent() {
      assertFalse("removeAll(disjointCollection) should return false",
          collection.removeAll(MinimalCollection.of(samples.e3)));
      expectUnchanged();
    }
  
    @CollectionFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemoveAll_allPresent() {
      assertTrue("removeAll(intersectingCollection) should return true",
          collection.removeAll(MinimalCollection.of(samples.e0)));
      expectMissing(samples.e0);
    }
  
    @CollectionFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemoveAll_somePresent() {
      assertTrue("removeAll(intersectingCollection) should return true",
          collection.removeAll(MinimalCollection.of(samples.e0, samples.e3)));
      expectMissing(samples.e0);
    }
  
    @CollectionFeature.Require({SUPPORTS_REMOVE,
        FAILS_FAST_ON_CONCURRENT_MODIFICATION})
    @CollectionSize.Require(SEVERAL)
    public void testRemoveAllSomePresentConcurrentWithIteration() {
      try {
        Iterator<E> iterator = collection.iterator();
        assertTrue(collection.removeAll(MinimalCollection.of(samples.e0, samples.e3)));
        iterator.next();
        fail("Expected ConcurrentModificationException");
      } catch (ConcurrentModificationException expected) {
        // success
      }
    }
  
    /**
     * Trigger the other.size() >= this.size() case in AbstractSet.removeAll().
     */
    @CollectionFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemoveAll_somePresentLargeCollectionToRemove() {
      assertTrue("removeAll(largeIntersectingCollection) should return true",
          collection.removeAll(MinimalCollection.of(
             samples.e0, samples.e0, samples.e0,
             samples.e3, samples.e3, samples.e3)));
     expectMissing(samples.e0);
   }
 
   @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
   public void testRemoveAll_unsupportedEmptyCollection() {
     try {
       assertFalse("removeAll(emptyCollection) should return false or throw "
           + "UnsupportedOperationException",
         collection.removeAll(MinimalCollection.of()));
     } catch (UnsupportedOperationException tolerated) {
     }
     expectUnchanged();
   }
 
   @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
   public void testRemoveAll_unsupportedNonePresent() {
     try {
       assertFalse("removeAll(disjointCollection) should return false or throw "
           + "UnsupportedOperationException",
         collection.removeAll(MinimalCollection.of(samples.e3)));
     } catch (UnsupportedOperationException tolerated) {
     }
     expectUnchanged();
   }
 
   @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
   @CollectionSize.Require(absent = ZERO)
   public void testRemoveAll_unsupportedPresent() {
     try {
       collection.removeAll(MinimalCollection.of(samples.e0));
       fail("removeAll(intersectingCollection) should throw "
           + "UnsupportedOperationException");
     } catch (UnsupportedOperationException expected) {
     }
     expectUnchanged();
     assertTrue(collection.contains(samples.e0));
   }
 
   /*
    * AbstractCollection fails the removeAll(null) test when the subject
    * collection is empty, but we'd still like to test removeAll(null) when we
    * can. We split the test into empty and non-empty cases. This allows us to
    * suppress only the former.
    */
 
   @CollectionFeature.Require(SUPPORTS_REMOVE)
   @CollectionSize.Require(ZERO)
   public void testRemoveAll_nullCollectionReferenceEmptySubject() {
     try {
       collection.removeAll(null);
       // Returning successfully is not ideal, but tolerated.
     } catch (NullPointerException expected) {
     }
   }
 
   @CollectionFeature.Require(SUPPORTS_REMOVE)
   @CollectionSize.Require(absent = ZERO)
   public void testRemoveAll_nullCollectionReferenceNonEmptySubject() {
     try {
       collection.removeAll(null);
       fail("removeAll(null) should throw NullPointerException");
     } catch (NullPointerException expected) {
     }
   }
 
   @CollectionFeature.Require(value = SUPPORTS_REMOVE,
       absent = ALLOWS_NULL_QUERIES)
   public void testRemoveAll_containsNullNo() {
     MinimalCollection<?> containsNull = MinimalCollection.of((Object) null);
     try {
       assertFalse("removeAll(containsNull) should return false or throw",
           collection.removeAll(containsNull));
     } catch (NullPointerException tolerated) {
     }
     expectUnchanged();
   }
 
   @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_QUERIES})
   public void testRemoveAll_containsNullNoButAllowed() {
     MinimalCollection<?> containsNull = MinimalCollection.of((Object) null);
     assertFalse("removeAll(containsNull) should return false",
         collection.removeAll(containsNull));
     expectUnchanged();
   }
 
   @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
   @CollectionSize.Require(absent = ZERO)
   public void testRemoveAll_containsNullYes() {
     initCollectionWithNullElement();
     assertTrue("removeAll(containsNull) should return true",
         collection.removeAll(Collections.singleton(null)));
     // TODO: make this work with MinimalCollection
   }
 
   @CollectionFeature.Require(SUPPORTS_REMOVE)
   public void testRemoveAll_containsWrongType() {
     try {
       assertFalse("removeAll(containsWrongType) should return false or throw",
           collection.removeAll(MinimalCollection.of(WrongType.VALUE)));
     } catch (ClassCastException tolerated) {
     }
     expectUnchanged();
   }
 }