code: private void checkConsistentReadAndIncrementPosition(Class<?> clazz, FakeEncodedItem item) {
        int endPosition = dataPosition + item.sizeBytes;
        for (int i = dataPosition; i < endPosition; i++) {
          FakeEncodedItem foundItemItem = i < dataSize ? data[i] : null;
          if (foundItemItem != item) {
            throw new UnreliableBehaviorError(
                clazz,
                dataPosition,
                item,
                String.format(
                    Locale.US,
                    "but [%s] interrupts it at position %d",
                    foundItemItem == null
                        ? "uninitialized data or the end of the buffer"
                        : foundItemItem.value,
                    i));
          }
        }
        dataPosition = Math.min(dataSize, dataPosition + item.sizeBytes);
      }
docs: Ensures that the next sizeBytes are all the initial value we read.
  
  <p>This detects:
  
  <ul>
  <li>Reading an item, but not starting at its start position
  <li>Reading items that were truncated by setSize
  <li>Reading items that were partially overwritten by another
  </ul>