Formal models and scripts: facetset-dimrange-and-rangeonrange-exclusive-bound-signed-zero-gap

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

• Facet-set DimRange.fromDoubles/fromFloats (and range-on-range DoubleRange) make an exclusive bound inclusive with Math.nextUp/Math.nextDown, which skip the other signed zero, so a facet set holding -0.0 is counted by neither of the adjacent ranges [-1, 0) and [0, 1] (finding LFV-1131; repro · finding page)

Files

• model/partition_smt.py (used for LFV-1131)
• model/replay_mbt.py (used for LFV-1131)

How to run

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

Snapshot of 2026-11-04. AI-assisted; not yet triaged by a human Lucene committer. Feedback: open an issue in lucene-ai-bug-hunt.