Graph<Integer> copy = copyOf(undirectedGraph);
    assertThat(copy).isEqualTo(undirectedGraph);
  }

  @Test
  public void copyOf_directedValueGraph() {
    ValueGraph<Integer, String> directedGraph = buildDirectedValueGraph();

    ValueGraph<Integer, String> copy = copyOf(directedGraph);
    assertThat(copy).isEqualTo(directedGraph);
  }

  @Test

  public void testCopyOf_map_empty() {
    Map<Class<?>, Object> in = Collections.emptyMap();
    ClassToInstanceMap<Object> map = ImmutableClassToInstanceMap.copyOf(in);
    assertTrue(map.isEmpty());
    assertSame(map, ImmutableClassToInstanceMap.of());
    assertSame(map, ImmutableClassToInstanceMap.copyOf(map));
  }

  public void testOf_zero() {
    assertTrue(ImmutableClassToInstanceMap.of().isEmpty());
  }

  public void testOf_one() {

    assertSame(c, ImmutableList.copyOf(c));
  }

  public void testCopyOf_shortcut_singleton() {
    Collection<String> c = ImmutableList.of("a");
    assertSame(c, ImmutableList.copyOf(c));
  }

  public void testCopyOf_shortcut_immutableList() {
    Collection<String> c = ImmutableList.of("a", "b", "c");
    assertSame(c, ImmutableList.copyOf(c));
  }

  private ListGenerators() {}

  public static class ImmutableListOfGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {
      return ImmutableList.copyOf(elements);
    }
  }

  public static class BuilderAddListGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {

    ImmutableBiMap<String, Integer> copy =
        ImmutableBiMap.copyOf(Collections.<String, Integer>emptyMap());
    assertEquals(Collections.<String, Integer>emptyMap(), copy);
    assertSame(copy, ImmutableBiMap.copyOf(copy));
    assertSame(ImmutableBiMap.of(), copy);
  }

  public void testCopyOfSingletonMap() {
    ImmutableBiMap<String, Integer> copy =

 * each immutable-collection class. This ensures, for example, that a call written "{@code
 * ImmutableSortedSet.copyOf()}" cannot secretly be a call to {@code ImmutableSet.copyOf()}.
 *
 * @author Chris Povirk
 */
public class FauxveridesTest extends TestCase {
  @AndroidIncompatible // similar to ImmutableTableTest.testNullPointerInstance

 * each immutable-collection class. This ensures, for example, that a call written "{@code
 * ImmutableSortedSet.copyOf()}" cannot secretly be a call to {@code ImmutableSet.copyOf()}.
 *
 * @author Chris Povirk
 */
public class FauxveridesTest extends TestCase {
  @AndroidIncompatible // similar to ImmutableTableTest.testNullPointerInstance

     */
    assertThat(ImmutableDoubleArray.copyOf(new double[0]))
        .isSameInstanceAs(ImmutableDoubleArray.of());
  }

  public void testCopyOf_array_nonempty() {
    double[] array = new double[] {0, 1, 3};
    ImmutableDoubleArray iia = ImmutableDoubleArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0.0, 1.0, 3.0).inOrder();
  }

    assertEquals(Collections.<String>emptySet(), copyOf(c));
    assertSame(c, copyOf(c));
  }

  public void testCopyOf_shortcut_singleton() {
    Collection<String> c = of("a");
    assertEquals(Collections.singleton("a"), copyOf(c));
    assertSame(c, copyOf(c));
  }

  public void testCopyOf_shortcut_sameType() {
    Collection<String> c = of("a", "b", "c");
    assertSame(c, copyOf(c));
  }

    assertEquals(Collections.<String>emptySet(), copyOf(c));
    assertSame(c, copyOf(c));
  }

  public void testCopyOf_shortcut_singleton() {
    Collection<String> c = of("a");
    assertEquals(Collections.singleton("a"), copyOf(c));
    assertSame(c, copyOf(c));
  }

  public void testCopyOf_shortcut_sameType() {
    Collection<String> c = of("a", "b", "c");
    assertSame(c, copyOf(c));
  }