histedit: pop action after the action is completed We only want to pop the action after the action is completed, since if the action aborts part way through we want it to remain at the front of the list so continue/abort will start with it. Previously we relied on the fact that we only serialized the state file at the beginning of the action, so the pop wasn't serialized until the next iteration of the loop. In a future patch we will be adding a large transaction around this area, which means if we pop the list early it might get serialized if the action throws a user InterventionRequired error, at which point the action is not in the list anymore. So let's only pop it once the action is really truly done.

histedit: add transaction support to writing the state file This will be used in a future diff to enable a single transaction around an entire histedit.

localrepo: forcibly copy list of filecache keys On Python 3, keys() is more like iterkeys(), so we got in trouble for mutating the dict while we're iterating here. Since the list of caches should be relatively small, work around this difference by just forcing a copy of the key list.

localrepo: turn hook kwargs back into strs before calling hook It might be better to ensure that the hook kwargs dict only has str keys on Python 3. I'm torn.

localrepo: ensure transaction id is fully bytes on py3

dirstate: use future-proof next(iter) instead of iter.next The latter has been removed in Python 3.