diff mercurial/changelog.py @ 47239:682f09857d69

revlogv2: delay the update of the changelog docket to transaction end

This prevent external reader to see the transaction content before it is
commited. However this also prevent the hooks to see the transaction content.
We will fix this in later changesets.

We have to temporarily suppress the error output of the command ran during the
transaction as they sometimes get confused about unknown working directory and
sometimes issue message on std-err in unspecified order.

Differential Revision: https://phab.mercurial-scm.org/D10629

--- a/mercurial/changelog.py	Mon May 03 12:34:52 2021 +0200
+++ b/mercurial/changelog.py	Mon May 03 12:35:02 2021 +0200
@@ -443,12 +443,13 @@
         self._filteredrevs = val
         self._filteredrevs_hashcache = {}
 
+    def _write_docket(self, tr):
+        if not self._delayed:
+            super(changelog, self)._write_docket(tr)
+
     def delayupdate(self, tr):
         """delay visibility of index updates to other readers"""
-        if self._docket is not None:
-            return
-
-        if not self._delayed:
+        if self._docket is None and not self._delayed:
             if len(self) == 0:
                 self._divert = True
                 if self._realopener.exists(self._indexfile + b'.a'):
@@ -468,7 +469,9 @@
         self._delayed = False
         self.opener = self._realopener
         # move redirected index data back into place
-        if self._divert:
+        if self._docket is not None:
+            self._write_docket(tr)
+        elif self._divert:
             assert not self._delaybuf
             tmpname = self._indexfile + b".a"
             nfile = self.opener.open(tmpname)