# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 2015-12-02 00:22:49
# Node ID b481bf14992d50bfa67d6fefe8adb6ad1a4c1c88
# Parent  5ebc4a192550df213816c3235d9b1dbf1a338609

addrevision: handle code path not producing delta

We would like to be able to exit the delta generation block without a valid
delta (for a more flexible control flow). So we make sure we do not expand the
"delta" content unless we actually have a delta.

We can do it one level lower because 'delta' is initialised at None anyway. Not
adding a level to the assignment prevent a line length issue.

diff --git a/mercurial/revlog.py b/mercurial/revlog.py
--- a/mercurial/revlog.py
+++ b/mercurial/revlog.py
@@ -1459,6 +1459,7 @@ class revlog(object):
                         delta = builddelta(prev)
             else:
                 delta = builddelta(prev)
+        if delta is not None:
             dist, l, data, base, chainbase, chainlen, compresseddeltalen = delta
 
         if not self._isgooddelta(delta, textlen):