dirstate: make writing in-memory changes aware of transaction activity This patch delays writing in-memory changes out, if transaction is running. '_getfsnow()' is defined as a function, to hook it easily for ambiguous timestamp tests (see also fakedirstatewritetime.py) 'if tr:' code path in this patch is still disabled at this revision, because there is no client invoking 'dirstate.write()' with repo object. BTW, this patch changes 'dirstate.invalidate()' semantics around 'dirstate.write()' in a transaction scope: before: with repo.transaction(): dirstate.CHANGE('A') dirstate.write() # change for A is written out here dirstate.CHANGE('B') dirstate.invalidate() # discards only change for B after: with repo.transaction(): dirstate.CHANGE('A') dirstate.write() # change for A is still kept in memory dirstate.CHANGE('B') dirstate.invalidate() # discards changes for A and B Fortunately, there is no code path expecting the former, at least, in Mercurial itself, because 'dirstateguard' was introduced to remove such 'dirstate.invalidate()'.

--- a/mercurial/localrepo.py	Wed Oct 14 02:49:17 2015 +0900
+++ b/mercurial/localrepo.py	Wed Oct 14 02:49:17 2015 +0900
@@ -1000,6 +1000,11 @@
         def releasefn(tr, success):
             repo = reporef()
             if success:
+                # this should be explicitly invoked here, because
+                # in-memory changes aren't written out at closing
+                # transaction, if tr.addfilegenerator (via
+                # dirstate.write or so) isn't invoked while
+                # transaction running
                 repo.dirstate.write()
             else:
                 # prevent in-memory changes from being written out at