# HG changeset patch
# User Gregory Szorc <gregory.szorc@gmail.com>
# Date 1514244674 25200
# Node ID a0fab647a8f1cc94202433160bdaeea29210aa3c
# Parent  711149d8e67672b5597a8335f6f9187b11e46b48
revlog: don't use slicing to return parents

This is the only place we use a slice on index entries, which
are currently tuples. In preparation for moving away from tuples,
let's stop using slices so we don't have to implement that support
on the new type.

We also tweak the logic slightly so the exception only catches the
IndexError on the index lookup, not on the index entry lookup. The
old code should never have been buggy. But it was semantically wrong.

Differential Revision: https://phab.mercurial-scm.org/D1764

diff -r 711149d8e676 -r a0fab647a8f1 mercurial/revlog.py
--- a/mercurial/revlog.py	Thu Jan 04 16:29:03 2018 -0800
+++ b/mercurial/revlog.py	Mon Dec 25 16:31:14 2017 -0700
@@ -622,12 +622,14 @@
 
     def parentrevs(self, rev):
         try:
-            return self.index[rev][5:7]
+            entry = self.index[rev]
         except IndexError:
             if rev == wdirrev:
                 raise error.WdirUnsupported
             raise
 
+        return entry[5], entry[6]
+
     def node(self, rev):
         try:
             return self.index[rev][7]