py3: replace str(ctx) by bytes(ctx) These are all for messages to the user and we don't want unicode for that.

py3: use inspect.signature() instead of inspect.getargspec() on py3

py3: use array.array.{to,from}bytes() on py3 array.array.{to,from}string() still exists on py3, but they're deprecated and generate warnings. I've put the compat function in compat.pt for now. We can move into a dedicated pycompat.py if we end up with a lot of py3 compat stuff.

py3: config values can be bytes, but never unicode

py3: call branchmap.items() on py3 and continue to call iteritems() on py2 Mercurial's source transformer also replaces the 'def iteritems(' in branchmap by 'def items(', so we need to call whichever version is there.

py3: switch from iteritems() to items() in the topics extension The only remaining iteritems() call is on branchmap. That will be dealt with in the next patch.

py3: filter() now returns a generator, so wrap when we need a list

py3: don't depend on map() iterating over its input map(some_generator()) in py2 returns a list, while in py3 it returns a generator, so the passed-in generator won't be called unless the returned one is.

py3: implement __bool__ in addition to __nonzero__

py3: replace iter.next() by next(iter)