Saxon

It's certainly in the same area as the previous bug, though not quite the same bug.

The MemoClosure / MemoSequence allocates a reservoir (buffer) of initial size 50 which is incrementally filled with items as required. If items are accessed by subscript, it reads input items up to the required subscript. When count is called, it reads all remaining items from the input and returns the total number of items in the reservoir. The code is incorrectly assuming that when all items have been read, the "reservoir" array will be the correct length. But in fact it is only condensed (from the initial size of 50) if the space saving looks worthwhile. If 30 items have been used, it decides that copying the array isn't worthwhile, but then incorrectly returns the length of the sequence as 50 rather than 30.

Patch committed to MemoSequence.ProgressiveIterator.materialize().

Patch applied in the Saxon 9.8.0.2 maintenance release