Merge branchname changes in localrepo.commit.

mercurial/localrepo.py

@@ -761,6 +761,8 b' class localrepository(repo.repository):'
             edittext.append("HG: user: %s" % user)
             if p2 != nullid:
                 edittext.append("HG: branch merge")
+            if branchname:
+                edittext.append("HG: branch %s" % util.tolocal(branchname))
             edittext.extend(["HG: changed %s" % f for f in changed])
             edittext.extend(["HG: removed %s" % f for f in removed])
             if not changed and not remove:
@@ -786,6 +788,9 b' class localrepository(repo.repository):'
                   parent2=xp2)
         tr.close()
 
+        if self.branchcache and "branch" in extra:
+            self.branchcache[util.tolocal(extra["branch"])] = n
+
         if use_dirstate or update_dirstate:
             self.dirstate.setparents(n)
             if use_dirstate: