verifySetContents(set, EMPTY_COLLECTION);
  }

  public void testNewTreeSetEmpty() {
    TreeSet<Integer> set = Sets.newTreeSet();
    verifySortedSetContents(set, EMPTY_COLLECTION, null);
  }

  public void testNewTreeSetEmptyDerived() {
    TreeSet<Derived> set = Sets.newTreeSet();
    assertTrue(set.isEmpty());
    set.add(new Derived("foo"));
    set.add(new Derived("bar"));

public final class SetsFilterSortedSetTest
    extends AbstractFilteredSortedSetTest<SortedSet<Integer>> {
  @Override
  SortedSet<Integer> createUnfiltered(Iterable<Integer> contents) {
    final TreeSet<Integer> result = Sets.newTreeSet(contents);
    // we have to make the result not Navigable
    return new ForwardingSortedSet<Integer>() {
      @Override
      protected SortedSet<Integer> delegate() {
        return result;
      }
    };

import java.util.NavigableSet;

public final class SetsFilterNavigableSetTest extends AbstractFilteredNavigableSetTest {
  @Override
  NavigableSet<Integer> createUnfiltered(Iterable<Integer> contents) {
    return Sets.newTreeSet(contents);
  }

  @Override
  NavigableSet<Integer> filter(
      NavigableSet<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);
  }

                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {
                    return Lists.newArrayList(Sets.newTreeSet(insertionOrder));
                  }
                })
            .named("ForwardingSortedSet[SafeTreeSet] with standard implementations")
            .withFeatures(
                CollectionSize.ANY,

                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {
                    return Lists.newArrayList(Sets.newTreeSet(insertionOrder));
                  }
                })
            .named("ForwardingSortedSet[SafeTreeSet] with standard implementations")
            .withFeatures(
                CollectionSize.ANY,

public final class SetsFilterSortedSetTest
    extends AbstractFilteredSortedSetTest<SortedSet<Integer>> {
  @Override
  SortedSet<Integer> createUnfiltered(Iterable<Integer> contents) {
    final TreeSet<Integer> result = Sets.newTreeSet(contents);
    // we have to make the result not Navigable
    return new ForwardingSortedSet<Integer>() {
      @Override
      protected SortedSet<Integer> delegate() {
        return result;
      }
    };

package com.google.common.collect.testing.google;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.Lists.newArrayList;
import static com.google.common.collect.Sets.newTreeSet;
import static com.google.common.collect.testing.SampleElements.Strings.AFTER_LAST;
import static com.google.common.collect.testing.SampleElements.Strings.AFTER_LAST_2;

    assertTrue(map.isEmpty());
    assertNull(map.get("five"));
  }

  private static class NonNavigableSortedSet extends ForwardingSortedSet<String> {
    private final SortedSet<String> delegate = Sets.newTreeSet();

    @Override
    protected SortedSet<String> delegate() {
      return delegate;
    }
  }

  public void testAsMapSorted() {
    SortedSet<String> strings = new NonNavigableSortedSet();

    assertTrue(map.isEmpty());
    assertNull(map.get("five"));
  }

  private static class NonNavigableSortedSet extends ForwardingSortedSet<String> {
    private final SortedSet<String> delegate = Sets.newTreeSet();

    @Override
    protected SortedSet<String> delegate() {
      return delegate;
    }
  }

  public void testAsMapSorted() {
    SortedSet<String> strings = new NonNavigableSortedSet();

package com.google.common.collect.testing.google;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.Lists.newArrayList;
import static com.google.common.collect.Sets.newTreeSet;
import static com.google.common.collect.testing.SampleElements.Strings.AFTER_LAST;
import static com.google.common.collect.testing.SampleElements.Strings.AFTER_LAST_2;