match: teach diffmatcher.visitdir() to return 'all' if possible This patch teaches differencematcher.visitdir() to return 'all' when m1.visitdir() returns 'all' and m2 does not matches. Before this patch, from a differencematcher.visitdir(), we always returned either True or False. We never returned 'all' even when we can. This causes problem when m1 and m2 of a differencematcher are themselves differencematcher. In that case, we try to check: `if self._m2_.visitdir(dir) == 'all'` which will never be 'all' even though it can be. This leads to iterating over a lot of sub-directory manifest, even though we don't want to while extending a narrow clone. I am yet to measure the impact of this but calculating manifest was taking ~50-60 seconds, so this should definitely save some of time there. Differential Revision: https://phab.mercurial-scm.org/D5814

Mercurial
=========

Mercurial is a fast, easy to use, distributed revision control tool
for software developers.

Basic install::

 $ make            # see install targets
 $ make install    # do a system-wide install
 $ hg debuginstall # sanity-check setup
 $ hg              # see help

Running without installing::

 $ make local      # build for inplace usage
 $ ./hg --version  # should show the latest version

See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.