Formal models and scripts: concurrent-collector-managers

Tools: Python

These are the working models and scripts this part of the hunt used. Some encode the code as it is (a counterexample is the expected result), others a fixed or correct variant; read the header comment of each file. Paths inside them were replaced by placeholders such as $LUCENE (a Lucene checkout) and $WORK.

Findings

• IndexSearcher throws IllegalArgumentException for any reader that contains a leaf with maxDoc() == 0 (for example a ParallelLeafReader with no sub-readers): the whole-segment LeafReaderContextPartition of that leaf fails a bounds check added for partition ranges (regression in 10.0.0) (finding LFV-202; repro · finding page)

Files

• leafslice-rejects-zero-doc-leaf/model/slice_partitions.py (used for LFV-202)

How to run

• Python: python3 <file>.py; scripts that import z3 need the z3-solver package.

Snapshot of 2026-11-03. AI-assisted; not yet triaged by a human Lucene committer. Feedback: open an issue in lucene-ai-bug-hunt.