[JCR-3401] Wrong results when querying with a DescendantSelfAxisQuery

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.7, 2.4.2, 2.5
• Fix Version/s: 2.4.3, 2.5.2
• Component/s: jackrabbit-core, query
• Assignee: Alex Deparvu
• Reporter: Cédric Damioli
• Created: 31/Jul/12 17:12
• Updated: 18/Sep/12 13:35
• Resolved: 09/Aug/12 08:56

Description

It seems to be caused by the DescendantSelfAxisScorer in the method advance(int target) :

        public int advance(int target) throws IOException {
            if (currentDoc == NO_MORE_DOCS) {
                return currentDoc;
            }

            // optimize in the case of an advance to finish.
            // see https://issues.apache.org/jira/browse/JCR-3082
            if (target == NO_MORE_DOCS) {
                subScorer.advance(target);
                currentDoc = NO_MORE_DOCS;
                return currentDoc;
            }

            currentDoc = subScorer.nextDoc();
            if (currentDoc == NO_MORE_DOCS) {
                return NO_MORE_DOCS;
            } else {
                collectContextHits();
                return isValid(currentDoc) ? currentDoc : nextDoc();
            }
        }

It seems to me that we should have:

currentDoc = subScorer.advance(target) 

instead of:

currentDoc = subScorer.nextDoc();

I could provide a patch but I don't know if this is necessary for a single line of code.
Moreover, I don't know if my fix is ok, as I'm not sure to fully understand the whole picture.