SpanOrQuery skipTo() doesn't always move forwards
-------------------------------------------------

                 Key: LUCENE-1583
                 URL: https://issues.apache.org/jira/browse/LUCENE-1583
             Project: Lucene - Java
          Issue Type: Bug
          Components: Search
    Affects Versions: 2.4.1, 2.4, 2.3.2, 2.3.1, 2.3, 2.2, 2.1, 2.0.0, 1.9
            Reporter: Moti Nisenson
            Priority: Minor


In SpanOrQuery the skipTo() method is improperly implemented if the target doc 
is less than or equal to the current doc, since skipTo() may not be called for 
any of the clauses' spans:

    public boolean skipTo(int target) throws IOException {
          if (queue == null) {
            return initSpanQueue(target);
          }

          while (queue.size() != 0 && top().doc() < target) {
            if (top().skipTo(target)) {
              queue.adjustTop();
            } else {
              queue.pop();
            }
          }
          
                return queue.size() != 0;
        }

This violates the correct behavior (as described in the Spans interface 
documentation), that skipTo() should always move forwards, in other words the 
correct implementation would be:

    public boolean skipTo(int target) throws IOException {
          if (queue == null) {
            return initSpanQueue(target);
          }

          boolean skipCalled = false;
          while (queue.size() != 0 && top().doc() < target) {
            if (top().skipTo(target)) {
              queue.adjustTop();
            } else {
              queue.pop();
            }
            skipCalled = true;
          }
          
          if (skipCalled) {
                return queue.size() != 0;
          }
          return next();
        }

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: java-dev-h...@lucene.apache.org

Reply via email to