# HG changeset patch
# User Yuya Nishihara <yuya@tcha.org>
# Date 2018-08-17 03:54:50
# Node ID 65d5de1169dd549a6fc0f8be6fa452ca4086e31e
# Parent  13a1901176f11825cf21c51d167cd1a0908b1f92

revlog: fix pure nodemap to not access missing index entry

This bug was revealed by a3dacabd476b and a1f934573c0b.

diff --git a/mercurial/revlog.py b/mercurial/revlog.py
--- a/mercurial/revlog.py
+++ b/mercurial/revlog.py
@@ -1107,7 +1107,9 @@ class revlog(object):
 
     @util.propertycache
     def nodemap(self):
-        self.rev(self.node(0))
+        if self.index:
+            # populate mapping down to the initial node
+            self.rev(self.node(0))
         return self._nodecache
 
     def hasnode(self, node):