deleteDocuments(Query) on a doc-values field is evaluated against stale values when doc-values updates are pending

Finding LFV-016Area: index / doc-values updatesPriority: highImpact: data corruptionNovelty: known upstream

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

What it shows

You update a doc-values field and then delete documents with a query on that field before the updates are written. You expect the delete to see the updated values. Instead delete-by-query is resolved against the written values, and inside a packet deletes run before doc-values updates, so the wrong documents are deleted or kept.

Expected vs actual

Expected: You expect the delete to see the updated values.
Actual: Delete-by-query is resolved against the written values, and inside a packet deletes run before doc-values updates, so the wrong documents are deleted or kept.

Files

src/TestVerifyDvDeleteQueryStaleness.java (JUnit test)

Run it

Tested on Lucene main e1faeba08bde (2026-11-02): still reproduces.
Tested on Lucene main b83101cdd2 (2026-10-23): reproduced.
Recorded outcome of run 1 on Lucene main a9779ef3c193: 9 test(s) run, 6 failed (testA1_deleteNewValueAfterUpdate_flushedSegment, testA2_deleteOldValueAfterUpdate_flushedSegment, testA3_deleteNewValueAfterUpdate_inRamDoc, testB1_crossPacket_resolvedButUnwrittenUpdate, testB2_tryUpdateDocValueThenDelete, testS1_softDeleteThenPurgeByExistsQuery).
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=$CP:randomizedtesting-runner-2.9.2.jar:junit-4.13.2.jar:hamcrest-3.0.jar   # test-framework dependencies (Maven Central)
CP=$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 -Xmx2g --add-modules jdk.incubator.vector --enable-native-access=ALL-UNNAMED -Dtests.seed=DEADBEEF \
     -cp "classes:$CP" org.junit.platform.console.ConsoleLauncher \
     execute --select-class TestVerifyDvDeleteQueryStaleness

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.