Classic Highlighter throws IllegalStateException for any query that contains a FieldExistsQuery (or a query that rewrites to one, such as an open-ended LongField range) when the token stream comes from term vectors with positions and offsets (regression in 10.5.0 from GITHUB#15678)

Finding LFV-824Area: highlighter / classic Highlighter (QueryScorer, WeightedSpanTermExtractor term-vector path)Priority: mediumImpact: crashNovelty: known upstream

Finding page for LFV-824

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

What it shows

You store a text field with term vectors (positions and offsets), search with a query such as +body:fox plus a FieldExistsQuery filter on another field, and highlight the hit with the classic Highlighter from its term vectors; you expect 'the quick brown <B>fox</B>', which 10.4.0 and earlier return. Since 10.5.0 the call throws IllegalStateException 'FieldExistsQuery requires that the field indexes doc values, norms or vectors, but field 'shadowed_field' exists and indexes neither of these data structures', naming an internal field the user never created. The highlighter rewrites the query against its own one-field reader built from the term vectors, whose field info has no norms or doc values, and since GITHUB#15678 it no longer skips FieldExistsQuery as GITHUB#12088 had made it do.

Expected vs actual

Expected: getBestFragment returns the quick brown <B>fox</B>, as on 10.4.0 and on main over re-analysed text.
Actual: IllegalStateException: FieldExistsQuery requires that the field indexes doc values, norms or vectors, but field 'shadowed_field' exists and indexes neither of these data structures; 2 of 3 tests fail.

Files

src/org/apache/lucene/search/highlight/TestHighlightFieldExistsTermVectors.java (JUnit test)

Run it

Tested on Lucene main e1faeba08bde (2026-11-02): still reproduces.
Tested on Lucene main a9779ef3c193 (2026-10-26): reproduced.
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/highlighter/build/libs/lucene-highlighter-$V.jar
CP=$CP:$LUCENE/lucene/memory/build/libs/lucene-memory-$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.search.highlight.TestHighlightFieldExistsTermVectors

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).

Files shown on the finding page

Feedback

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