}

  @Test fun noMoreThanOneWorkerThreadWaitingToStartAtATime() {
    // Enqueueing the red task starts a thread because the head of the queue changed.
    redQueue.execute("red task") {
      log += "red:starting@${taskFaker.nanoTime}"
      taskFaker.sleep(100.µs)
      log += "red:finishing@${taskFaker.nanoTime}"
    }
    assertThat(taskFaker.executeCallCount).isEqualTo(1)

   * Example usage:
   *
   * <pre>{@code
   * Color red = new Color("red", 255, 0, 0);
   * ...
   * ImmutableSet<Color> allColors = ImmutableSet.of(red, green, blue);
   *
   * ImmutableMap<String, Color> colorForName =
   *     uniqueIndex(allColors, c -> c.toString());
   * assertThat(colorForName).containsEntry("red", red);
   * }</pre>
   *

   * public static final ImmutableMultiset<Bean> BEANS =
   *     new ImmutableMultiset.Builder<Bean>()
   *         .addCopies(Bean.COCOA, 4)
   *         .addCopies(Bean.GARDEN, 6)
   *         .addCopies(Bean.RED, 8)
   *         .addCopies(Bean.BLACK_EYED, 10)
   *         .build();
   * }</pre>
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build

   *     new ImmutableSortedMultiset.Builder<Bean>(colorComparator())
   *         .addCopies(Bean.COCOA, 4)
   *         .addCopies(Bean.GARDEN, 6)
   *         .addCopies(Bean.RED, 8)
   *         .addCopies(Bean.BLACK_EYED, 10)
   *         .build();
   * }</pre>
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build