[LUCENE-7576] RegExp automaton causes NPE on Terms.intersect

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 6.2.1
• Fix Version/s: 6.4, 7.0
• Component/s: core/codecs, core/index

Environment

java version "1.8.0_77" macOS 10.12.1

• Lucene Fields: New
• Assignee: Michael McCandless
• Reporter: Tom Mortimer
• Created: 28/Nov/16 17:10
• Updated: 28/Aug/22 18:07
• Resolved: 02/Dec/16 23:29

Description

Calling org.apache.lucene.index.Terms.intersect(automaton, null) causes an NPE:

String index_path = <path to index>
String term = <a valid term name>

Directory directory = FSDirectory.open(Paths.get(index_path));
IndexReader reader = DirectoryReader.open(directory);
Fields fields = MultiFields.getFields(reader);
Terms terms = fields.terms(args[1]);
CompiledAutomaton automaton = new CompiledAutomaton(
new RegExp("do_not_match_anything").toAutomaton());

TermsEnum te = terms.intersect(automaton, null);

throws:

Exception in thread "main" java.lang.NullPointerException
at org.apache.lucene.codecs.blocktree.IntersectTermsEnum.<init>(IntersectTermsEnum.java:127)
at org.apache.lucene.codecs.blocktree.FieldReader.intersect(FieldReader.java:185)
at org.apache.lucene.index.MultiTerms.intersect(MultiTerms.java:85)
...