CompositeVerifyQuery's Weight reports itself cacheable from its shape predicate alone and ignores the index query it runs, so after an in-place doc-values update a query cache keeps returning the old matches

Finding LFV-947Area: spatial-extras / composite: CompositeVerifyQuery (Weight#isCacheable) and the query cachePriority: lowImpact: silent wrong resultsNovelty: new

Finding page for LFV-947

AI-assisted finding, confirmed by automated checks, not yet triaged by a human Lucene committer. This site files nothing upstream.

What it shows

You wrap an index query that reads a doc-values field, for example NumericDocValuesField.newSlowExactQuery("v", 1), in new CompositeVerifyQuery(indexQuery, shapePredicate), run it through a query cache, then change that field for one document in place with IndexWriter#updateNumericDocValue and reopen the reader. You expect the reopened searcher to see the new value, because a query that depends on updated doc values must report itself not cacheable (SegmentCacheable), and the index query alone does. Instead CompositeVerifyQuery's Weight#isCacheable asks only the shape predicate, the segment keeps its core cache key, and the cache keeps serving the pre-update result ([0, 1, 2] instead of [1, 2] in the repro; 5025 instead of 5024 hits with the release-default cache settings).

The test shows that a CompositeVerifyQuery whose index query reads doc values (NumericDocValuesField.newSlowExactQuery("v", 1)) stays cached across an in-place updateNumericDocValue and reopen, because its Weight#isCacheable asks only the shape predicate.

Expected vs actual

Expected count 0 after doc 0's v changes from 1 to 2; actual 1 (the pre-update cache entry), with -ea and -da (expected:<0> but was:<1>).

Files

• src/org/apache/lucene/spatial/composite/TestCompositeVerifyQueryCacheability.java (JUnit test)

Run it

• Tested on Lucene main e1faeba08bde (2026-11-02): still reproduces.
• Tested on Lucene main 645d4fe14a20 (2026-10-28): reproduced.
• Recorded outcome of run 1 on Lucene main 645d4fe14a20: 1 test(s) run, 1 failed.
• How to read the outcome: a failing test is the finding reproducing (the failure message states expected against actual).
• Seeds: a rerun with the same seed replays the same random choices. Assertions off (-da -dsa -Dtests.asserts=false) is the production-like setting.

# Lucene checkout at the tested commit, built with: ./gradlew --no-daemon assemble   (JDK 25)
LUCENE=/path/to/lucene; V=12.0.0-SNAPSHOT
CP=$LUCENE/lucene/core/build/libs/lucene-core-$V.jar
CP=$CP:$LUCENE/lucene/codecs/build/libs/lucene-codecs-$V.jar
CP=$CP:$LUCENE/lucene/test-framework/build/libs/lucene-test-framework-$V.jar
CP=$CP:$LUCENE/lucene/spatial-extras/build/libs/lucene-spatial-extras-$V.jar
CP=$CP:$LUCENE/lucene/spatial3d/build/libs/lucene-spatial3d-$V.jar
CP=$CP:randomizedtesting-runner-2.9.2.jar:junit-4.13.2.jar:hamcrest-3.0.jar   # test-framework dependencies (Maven Central)
CP=$CP:junit-platform-console-standalone-6.1.3.jar   # JUnit Platform console launcher (Maven Central)

javac -d classes -cp "$CP" $(find src -name '*.java')

# run 1: assertions on, seed DEADBEEF
java -ea -esa --add-modules jdk.incubator.vector --enable-native-access=ALL-UNNAMED -Dtests.seed=DEADBEEF \
     -cp "classes:$CP" org.junit.platform.console.ConsoleLauncher \
     execute --select-class org.apache.lucene.spatial.composite.TestCompositeVerifyQueryCacheability

The module(s) spatial-extras also need their third-party runtime jars; ./gradlew -p lucene/<module> dependencies lists them.

Gradle alternative: copy the test into the matching module's src/test/ tree of the checkout and run ./gradlew -p lucene/<module> test --tests <class> -Ptests.seed=<seed> (add -Ptests.asserts=false for a run without assertions).

Feedback

Open an issue in lucene-ai-bug-hunt. Please do not open issues or pull requests in apache/lucene about this finding unless a Lucene committer agrees it should be filed.

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