}

  static class SerializableThrowingSupplier extends ThrowingSupplier implements Serializable {
    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0L;
  }

  static void checkMemoize(CountingSupplier countingSupplier, Supplier<Integer> memoizedSupplier) {
    // the underlying supplier hasn't executed yet
    assertEquals(0, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());