/*
    * Copyright (C) 2011 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;
  
  import com.google.common.annotations.GwtIncompatible;
  
  import junit.framework.TestCase;
  
  import java.util.Iterator;
  import java.util.List;
  import java.util.NoSuchElementException;
  
  /**
   * Base class for {@link RangeSet} tests.
   *
   * @author Louis Wasserman
   */
  @GwtIncompatible("TreeRangeSet")
  public abstract class AbstractRangeSetTest extends TestCase {
    public static void testInvariants(RangeSet<?> rangeSet) {
      testInvariantsInternal(rangeSet);
      testInvariantsInternal(rangeSet.complement());
    }
  
    private static <C extends Comparable> void testInvariantsInternal(RangeSet<C> rangeSet) {
      assertEquals(rangeSet.asRanges().isEmpty(), rangeSet.isEmpty());
      assertEquals(!rangeSet.asRanges().iterator().hasNext(), rangeSet.isEmpty());
  
      List<Range<C>> asRanges = ImmutableList.copyOf(rangeSet.asRanges());
  
      // test that connected ranges are coalesced
      for (int i = 0; i + 1 < asRanges.size(); i++) {
        Range<C> range1 = asRanges.get(i);
        Range<C> range2 = asRanges.get(i + 1);
        assertFalse(range1.isConnected(range2));
      }
  
      // test that there are no empty ranges
      for (Range<C> range : asRanges) {
        assertFalse(range.isEmpty());
      }
  
      Iterator<Range<C>> itr = rangeSet.asRanges().iterator();
      Range<C> expectedSpan = null;
      if (itr.hasNext()) {
        expectedSpan = itr.next();
        while (itr.hasNext()) {
          expectedSpan = expectedSpan.span(itr.next());
        }
      }
  
      try {
        Range<C> span = rangeSet.span();
        assertEquals(expectedSpan, span);
      } catch (NoSuchElementException e) {
        assertNull(expectedSpan);
      }
    }
  }