DO NOT REPLY [Bug 9556] New: - Subgroup wrong when matching (.)(?=(.)) against "XY"?

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=9556

Subgroup wrong when matching (.)(?=(.)) against "XY"?

           Summary: Subgroup wrong when matching (.)(?=(.)) against "XY"?
           Product: ORO
           Version: 2.0.6
          Platform: PC
        OS/Version: Windows XP
            Status: NEW
          Severity: Minor
          Priority: Other
         Component: Main
        AssignedTo: [email protected]
        ReportedBy: [email protected]


The following case behaves as I would expect:
   Perl5 Expression: (.)(?=(.))(.)
   Search Input: XYZ
   Match 1: XY
      Subgroups:
         1: X
         2: Y
         3: Y

But the slightly simpler case, below, doesn't seem to match the 2nd subgroup
correctly:
   Perl5 Expression: (.)(?=(.))
   Search Input: XY
   Match 1: X
      Subgroups:
         1: X
         2:

Shouldn't the second subgroup in the second case be "Y" instead of blank?
I'm trying this in the "Demonstration Applet" from version 2.0.6.