The intervals disjunction rewrite looks only one level into an or(), so an or() inside a maxwidth, fixField or extend wrapper (or inside an ordered()) that is itself one alternative of another or() is never split, and phrase, maxgaps or containedBy miss hits: phrase(x, or(maxwidth(5, or("b c", b)), y), d) misses 'x b c d', which phrase(x, maxwidth(5, or("b c", b)), d) matches
Finding LFV-826Area: queries / intervals (gap-sensitive disjunction rewrite of LUCENE-8477: Disjunctions.splitDisjunctions and Disjunctions.pullUp vs an alternative of an or() that has disjunctions of its own: maxwidth, extend, fixField, ordered)Priority: lowImpact: silent wrong resultsNovelty: new
AI-assisted finding, confirmed by automated checks, not yet triaged by a human Lucene committer. This site files nothing upstream.
What it shows
You build phrase(x, or(W, y), d) with W = maxwidth(5, or(phrase(b, c), b)) and expect the hit on 'x b c d' that phrase(x, W, d) finds, because Intervals.or 'Automatically rewrites if wrapped by an interval source that is sensitive to internal gaps' and adding an alternative y that occurs in no document cannot remove a match. Instead the rewrite (Disjunctions.splitDisjunctions) asks the outer or() for its alternatives only one level deep, so W reaches the phrase whole (here grouped with y into one minimizing or(), because W's shortest match is one position), the inner or() drops the interval 'b c' in favour of the 'b' it contains, and the query returns no hits. The same happens with fixField(g, or(...)) or extend(or(...), 0, 0) in place of maxwidth, with containedBy or maxgaps as the parent, and with an ordered() alternative whose own or() has alternatives of different lengths.
The test shows that phrase(x, or(maxwidth(5, or(phrase(b, c), b)), y), d) misses x b c d, because the disjunction rewrite splits the outer or() only one level deep and never splits the or() inside maxwidth.
Expected vs actual
Expected: 1 hit (y occurs nowhere, and phrase(x, maxwidth(5, or(phrase(b, c), b)), d) matches). Actual: 0 hits (expected:<1> but was:<0>).
Files
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/queries/build/libs/lucene-queries-$V.jar
CP=$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.queries.intervals.TestPhraseOverOrOfWrappedOrGradle 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.