*       href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
   *       graph elements</a> for details)
   * </ul>
   *
   * @throws IllegalArgumentException if {@code node} is not an element of this graph
   */
  Iterable<? extends N> predecessors(N node);

        assertTrue(exception.getStackTrace().length > 0);

        // Verify the stack trace contains this test method
        boolean foundTestMethod = false;
        for (StackTraceElement element : exception.getStackTrace()) {
            if (element.getMethodName().equals("test_stackTrace")) {
                foundTestMethod = true;
                break;
            }
        }
        assertTrue(foundTestMethod);
    }

  public void testSet_replacingNull() {
    E[] elements = createSamplesArray();
    int i = aValidIndex();
    elements[i] = null;
    collection = getSubjectGenerator().create(elements);

    doTestSet(e3());
  }

  private void doTestSet(E newValue) {
    int index = aValidIndex();
    E initialValue = getList().get(index);
    assertEquals(
        "set(i, x) should return the old element at position i.",
        initialValue,

        if (javahome == null) {
            throw new MisconfiguredToolchainException(
                    "Java toolchain without the " + JavaToolchainImpl.KEY_JAVAHOME + " configuration element.");
        }
        Path normal = Paths.get(javahome.getValue()).normalize();
        if (Files.exists(normal)) {
            jtc.setJavaHome(Paths.get(javahome.getValue()).normalize().toString());
        } else {

    multimap().replaceValues(k3(), values);
    assertGet(k3(), values);
    assertEquals(size + values.size(), multimap().size());
  }

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  public void testReplaceValuesWithEmpty() {
    int size = multimap().size();
    List<V> oldValues = new ArrayList<>(multimap().get(k0()));

  public void testRemove_unsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getMap().remove(k0()));
    expectUnchanged();
    assertEquals("remove(present) should not remove the element", v0(), get(k0()));
  }

  @MapFeature.Require(absent = SUPPORTS_REMOVE)
  public void testRemove_unsupportedNotPresent() {
    try {
      assertNull(

    List<E> containsNull = singletonList(null);
    assertTrue("addAll(n, containsNull) should return true", getList().addAll(0, containsNull));
    /*
     * We need (E) to force interpretation of null as the single element of a
     * varargs array, not the array itself
     */
    expectAdded(0, (E) null);
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)

   * by delaying the per-stack-frame work until each element is accessed. Roughly speaking:
   *
   * <ul>
   *   <li>{@code getStackTrace} takes {@code stackSize} time to return but then negligible time to
   *       retrieve each element of the returned list.
   *   <li>{@code lazyStackTrace} takes negligible time to return but then {@code 1/stackSize} time
   *       to retrieve each element of the returned list (probably slightly more than {@code

        String[] result = invokeDistinct(input);
        assertSame(input, result);
    }

    @Test
    public void test_distinct_singleElement() {
        // Test distinct with single element
        String[] input = new String[] { "element" };
        String[] result = invokeDistinct(input);
        assertSame(input, result);
    }

    @Test
    public void test_distinct_noDuplicates() {

    List<E> containsNull = singletonList(null);
    assertTrue("addAll(n, containsNull) should return true", getList().addAll(0, containsNull));
    /*
     * We need (E) to force interpretation of null as the single element of a
     * varargs array, not the array itself
     */
    expectAdded(0, (E) null);
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)