return list;
              }
            });

    if (expectedLines.isEmpty()) {
      assertTrue(list.isEmpty());
    } else {
      assertEquals(expectedLines.subList(0, 1), list);
    }
  }

  private void assertExpectedString(String string) {
    assertEquals(expected, string);
  }

  private void assertExpectedLines(List<String> list) {

                return list;
              }
            });

    if (expectedLines.isEmpty()) {
      assertTrue(list.isEmpty());
    } else {
      assertEquals(expectedLines.subList(0, 1), list);
    }
  }

  public void testForEachLine() throws IOException {
    ImmutableList.Builder<String> builder = ImmutableList.builder();
    source.forEachLine(builder::add);