[LUCENE-800] Incorrect parsing by QueryParser.parse() when it encounters backslashes (always eats one backslash.)

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.2
• Component/s: core/queryparser
• Lucene Fields: New
• Assignee: Michael Busch
• Reporter: Dilip Nimkar
• Created: 13/Feb/07 19:50
• Updated: 28/Aug/22 11:34
• Resolved: 08/Mar/07 04:27

Description

Test code and output follow. Tested Lucene 1.9 version only. Affects hose who would index/search for Lucene's reserved characters.

Description: When an input search string has a sequence of N (java-escaped) backslashes, where N >= 2, the QueryParser will produce a query in which that sequence has N-1 backslashes.

TEST CODE:
Analyzer analyzer = new WhitespaceAnalyzer();
String[] queryStrs =

{"item:\\\\", "item:\\\\*", "(item:\\\\ item:ABCD\\\\))", "(item:\\\\ item:ABCD\\\\)"}

;
for (String queryStr : queryStrs) {
System.out.println("--------------------------------------");
System.out.println("String queryStr = " + queryStr);
Query luceneQuery = null;
try

{ luceneQuery = new QueryParser("_default_", analyzer).parse(queryStr); System.out.println("luceneQuery.toString() = " + luceneQuery.toString()); }

catch (Exception e)

{ System.out.println(e.getClass().toString()); }

}

OUTPUT (with remarks in comment notation
--------------------------------------
String queryStr = item:
luceneQuery.toString() = item:\ //One backslash has disappeared. Searcher will fail on this query.
--------------------------------------
String queryStr = item:
*
luceneQuery.toString() = item:* //One backslash has disappeared. This query will search for something unintended.
--------------------------------------
String queryStr = (item:
item:ABCD
))
luceneQuery.toString() = item:\ item:ABCD) //This should have thrown a ParseException because of an unescaped ')'. It did not.
--------------------------------------
String queryStr = (item:
item:ABCD
)
class org.apache.lucene.queryParser.ParseException //...and this one should not have, but it did.