diff mercurial/localrepo.py @ 20883:cd443c7589cc

fncache: move fncache writing to be in a transaction

Previously the fncache was written at lock.release time. This meant it was not
tracked by a transaction, and if an error occurred during the fncache write it
would fail to update the fncache, but would not rollback the transaction,
resulting in an fncache that was not in sync with the files on disk (which
causes verify to fail, and causes streaming clones to not copy all the revlogs).

This uses the new transaction backup mechanism to make the fncache transacted.
It also moves the fncache from being written at lock.release time, to being
written at transaction.close time.

--- a/mercurial/localrepo.py	Mon Mar 24 15:21:51 2014 -0700
+++ b/mercurial/localrepo.py	Mon Mar 24 15:42:13 2014 -0700
@@ -823,13 +823,17 @@
             raise error.RepoError(
                 _("abandoned transaction found - run hg recover"))
 
+        def onclose():
+            self.store.write(tr)
+
         self._writejournal(desc)
         renames = [(vfs, x, undoname(x)) for vfs, x in self._journalfiles()]
         rp = report and report or self.ui.warn
         tr = transaction.transaction(rp, self.sopener,
                                      "journal",
                                      aftertrans(renames),
-                                     self.store.createmode)
+                                     self.store.createmode,
+                                     onclose)
         self._transref = weakref.ref(tr)
         return tr
 
@@ -1037,7 +1041,6 @@
             return l
 
         def unlock():
-            self.store.write()
             if hasunfilteredcache(self, '_phasecache'):
                 self._phasecache.write()
             for k, ce in self._filecache.items():