README

match: optimize visitdir() for when no explicit files are listed

In patternmatcher, we used to say that all directories should be
visited if no explicit files were listed, because the case of empty
_files usually implied that no patterns were given (which in turns
meant that everything should match). However, this made e.g. "hg files
-r .  rootfilesin:."  slower than necessary, because that also ended
up with an empty list in _files. Now that patternmatcher does not
handle includes, the only remaining case where its _files/_fileset
fields will be empty is when it's matching everything. We can
therefore treat the always-case specially and stop treating the empty
_files case specially. This makes the case mentioned above faster on
treemanifest repos.

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.