@GetSize
  public double getSize(
      @Element SubscriptionPartition subscriptionPartition,
      @Restriction OffsetByteRange restriction) {
    if (restriction.getRange().getTo() != Long.MAX_VALUE) {
      return restriction.getByteCount();
    }
    return newTracker(subscriptionPartition, restriction).getProgress().getWorkRemaining();
  }
@Test
  public void getProgressUnboundedRangeDelegates() {
    Progress progress = Progress.from(0, 0.2);
    when(tracker.getProgress()).thenReturn(progress);
    assertTrue(
        DoubleMath.fuzzyEquals(
            progress.getWorkRemaining(), sdf.getSize(PARTITION, RESTRICTION), .0001));
    verify(tracker).getProgress();
  }