content: /*
   * Copyright 2015, 2024 StreamEx contributors
   *
   * 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 one.util.streamex;
  
  import org.junit.Test;
  
  import java.util.*;
  import java.util.concurrent.ConcurrentLinkedDeque;
  
  import static one.util.streamex.TestHelpers.consumeElement;
  import static org.junit.Assert.*;
  
  /**
   * @author Tagir Valeev
   *
   */
  public class TailConcatSpliteratorTest {
      @Test
      public void testCharacteristics() {
          TailConcatSpliterator<Integer> spltr = new TailConcatSpliterator<>(IntStreamEx.range(1000).spliterator(), IntStreamEx.range(1000).spliterator());
          assertTrue(spltr.hasCharacteristics(Spliterator.SIZED));
          assertTrue(spltr.hasCharacteristics(Spliterator.SUBSIZED));
          assertTrue(spltr.hasCharacteristics(Spliterator.ORDERED));
          assertEquals(2000, spltr.getExactSizeIfKnown());
  
          spltr = new TailConcatSpliterator<>(Spliterators.emptySpliterator(), Spliterators.emptySpliterator());
          assertTrue(spltr.hasCharacteristics(Spliterator.SIZED));
          assertEquals(0, spltr.getExactSizeIfKnown());
  
          spltr = new TailConcatSpliterator<>(IntStreamEx.range(1000).spliterator(), new HashSet<>(Arrays.asList(1, 2, 3)).spliterator());
          assertTrue(spltr.hasCharacteristics(Spliterator.SIZED));
          assertFalse(spltr.hasCharacteristics(Spliterator.SUBSIZED));
          assertFalse(spltr.hasCharacteristics(Spliterator.ORDERED));
          assertEquals(1003, spltr.getExactSizeIfKnown());
          spltr.tryAdvance(x -> assertEquals(0, (int) x));
          assertEquals(1002, spltr.getExactSizeIfKnown());
          
          TailConcatSpliterator<Long> longSpltr = new TailConcatSpliterator<>(LongStreamEx.range(Long.MAX_VALUE / 2 + 1)
                  .spliterator(), LongStreamEx.range(Long.MAX_VALUE / 2 + 1).spliterator());
          assertFalse(longSpltr.hasCharacteristics(Spliterator.SIZED));
          assertFalse(longSpltr.hasCharacteristics(Spliterator.SUBSIZED));
          assertTrue(longSpltr.hasCharacteristics(Spliterator.ORDERED));
          assertEquals(Long.MAX_VALUE, longSpltr.estimateSize());
          longSpltr.tryAdvance(x -> assertEquals(0L, (long) x));
          assertEquals(Long.MAX_VALUE, longSpltr.estimateSize());
          
          Queue<Integer> q = new ConcurrentLinkedDeque<>();
          spltr = new TailConcatSpliterator<>(q.spliterator(), q.spliterator());
          q.add(1);
          assertFalse(longSpltr.hasCharacteristics(Spliterator.SIZED));
          consumeElement(spltr, 1);
          consumeElement(spltr, 1);
          assertFalse(spltr.tryAdvance(x -> fail("Should not happen")));
      }
  }
  