assertThat(network.edgesConnecting("A", "A")).containsExactly("AA");
    assertThat(network.edgesConnecting("A", "B")).containsExactly("AB");
    assertThat(network.edgesConnecting("B", "A")).isEmpty();
  }

  @Test
  public void edgesConnecting_undirected() {
    MutableNetwork<String, String> mutableNetwork =
        NetworkBuilder.undirected().allowsSelfLoops(true).build();

            .collect { it.trim() }
            .grep { !it.isEmpty() }
    }

    static List<String> parentCommitsOf(String commit) {
        return getStdout("git show --format=%P --no-patch --no-show-signature $commit")
            .split(" ").collect { it.trim() }.grep { !it.isEmpty() }
    }

    @groovy.transform.ToString
    static class ExecResult {
        String stdout

   * chars are actually available for reading. This means that a source may return {@code true} from
   * {@code isEmpty()} despite having readable content.
   *
   * @throws IOException if an I/O error occurs
   * @since 15.0
   */
  public boolean isEmpty() throws IOException {
    Optional<Long> lengthIfKnown = lengthIfKnown();
    if (lengthIfKnown.isPresent()) {

   * chars are actually available for reading. This means that a source may return {@code true} from
   * {@code isEmpty()} despite having readable content.
   *
   * @throws IOException if an I/O error occurs
   * @since 15.0
   */
  public boolean isEmpty() throws IOException {
    Optional<Long> lengthIfKnown = lengthIfKnown();
    if (lengthIfKnown.isPresent()) {

    assertThat(rangeSet.asRanges()).isEmpty();
    assertEquals(ImmutableRangeSet.<Integer>all(), rangeSet.complement());
    assertFalse(rangeSet.contains(0));
    assertFalse(rangeSet.intersects(Range.singleton(0)));
    assertFalse(rangeSet.encloses(Range.singleton(0)));
    assertTrue(rangeSet.enclosesAll(rangeSet));
    assertTrue(rangeSet.isEmpty());
  }

  public void testAll() {

        if (!loaded.isEmpty()) {
            result.add(new CoreExtensions(file, loaded));
        }

        // user
        file = context.userHomeDirectory.resolve(eff.get(Constants.MAVEN_USER_EXTENSIONS));
        loaded = readCoreExtensionsDescriptorFromFile(file, true);
        if (!loaded.isEmpty()) {
            result.add(new CoreExtensions(file, loaded));
        }

  }

  public void testIsEmpty() {
    assertThat(ImmutableLongArray.of().isEmpty()).isTrue();
    assertThat(ImmutableLongArray.of(0).isEmpty()).isFalse();
    assertThat(ImmutableLongArray.of(0, 1, 3).isEmpty()).isFalse();
    assertThat(ImmutableLongArray.of(0, 1, 3).subArray(1, 1).isEmpty()).isTrue();
    assertThat(ImmutableLongArray.of(0, 1, 3).subArray(1, 2).isEmpty()).isFalse();
  }

  public void testGet_good() {

    this.ticker = firstNonNull(builder.ticker, Ticker.systemTicker());
  }

  @Override
  public int size() {
    return cachingHashMap.size();
  }

  @Override
  public boolean isEmpty() {
    return cachingHashMap.isEmpty();
  }

  @Override
  public V get(Object key) {
    checkNotNull(key);
    Timestamped<V> value = cachingHashMap.get(key);

    if (value == null) {

        if (!blackList.contains(id)) {
            blackList.add(id);

            List<String> dependents = sorter.getDependents(id);

            if (dependents != null && !dependents.isEmpty()) {
                for (String dependentId : dependents) {
                    if (!buildSuccessesByProject.containsKey(dependentId)
                            && !buildFailuresByProject.containsKey(dependentId)) {

    }

    /**
     *
     */
    @Test
    public void testIsEmpty() {
        assertTrue(StringUtil.isEmpty(null));
        assertTrue(StringUtil.isEmpty(""));
        assertFalse(StringUtil.isEmpty(" "));
    }

    /**
     *
     */
    @Test
    public void testIsNotEmpty() {
        assertFalse(StringUtil.isNotEmpty(null));