# HG changeset patch
# User Matt Mackall <mpm@selenic.com>
# Date 1243453495 18000
# Node ID c2ef478b2efad5696cd786297af84e39b02c3af6
# Parent  648af8a6aa414c06f5cd410f70acccce0f49a23b
changelog: make delayopener less intrusive

diff -r 648af8a6aa41 -r c2ef478b2efa mercurial/changelog.py
--- a/mercurial/changelog.py	Wed May 27 14:44:54 2009 -0500
+++ b/mercurial/changelog.py	Wed May 27 14:44:55 2009 -0500
@@ -89,19 +89,20 @@
 
 class changelog(revlog.revlog):
     def __init__(self, opener):
-        revlog.revlog.__init__(self, opener, "00changelog.i")
+        self._realopener = opener
+        self._delayed = False
+        revlog.revlog.__init__(self, self._delayopener, "00changelog.i")
 
     def delayupdate(self):
         "delay visibility of index updates to other readers"
-        self._realopener = self.opener
-        self.opener = self._delayopener
+        self._delayed = True
         self._delaycount = len(self)
         self._delaybuf = []
         self._delayname = None
 
     def finalize(self, tr):
         "finalize index updates"
-        self.opener = self._realopener
+        self._delayed = False
         # move redirected index data back into place
         if self._delayname:
             util.rename(self._delayname + ".a", self._delayname)
@@ -116,7 +117,7 @@
     def _delayopener(self, name, mode='r'):
         fp = self._realopener(name, mode)
         # only divert the index
-        if not name == self.indexfile:
+        if not self._delayed or not name == self.indexfile:
             return fp
         # if we're doing an initial clone, divert to another file
         if self._delaycount == 0: