branchcache: do not accept "empty update"
This currently does not happens and it will be simpler that is remains that way.
If all update do something, we will be able to simply declare, in a later
changesets, that all update to result in a dirty branchcache.
--- a/mercurial/branchmap.py Thu Mar 07 11:04:34 2024 +0100
+++ b/mercurial/branchmap.py Fri Mar 08 15:06:54 2024 +0100
@@ -302,7 +302,8 @@
self._closednodes.add(cl.node(r))
max_rev = max(max_rev, r)
if max_rev < 0:
- max_rev = None
+ msg = "running branchcache.update without revision to update"
+ raise error.ProgrammingError(msg)
# Delay fetching the topological heads until they are needed.
# A repository without non-continous branches can skip this part.