view README @ 32176:cf042543afa2

match: optimize visitdir() for patterns matching only root directory

Because _rootsanddirs() returns a list of directories to visit
recursively and a list of directories to visit non-recursively. For
patterns such as 'rootfilesin:foo/bar', we clearly need to visit the
directory foo/bar, but we also need to visit its parents. The method
therefore uses util.dirs() to find the parent directories of
'foo/bar'. That method does not include the root directory, but since
we obviously need to visit the root directory, we always added '.' to
the set of directories to visit non-recursively.

The visitdir() method had special handling to consider set(['.']) to
mean that no includes had been specified and would thus visit all
directories. However, when the pattern is 'rootfilesin:.', set(['.'])
is actually the real set of directories to visit and the special
handling of that set meant that all directories got visited instead of
just the root directory.

The fix is simple: add '.' to the set of parent directories in
_rootsanddirs() and stop treating set(['.']) specially. This makes

  hg files -r .  -I rootfilesin:.

in a treemanifest version of the Firefox repo go from 1.5s to 0.26s on
warm disk (and a *much* bigger improvement on cold disk).

Note that the -I is necessary for no good reason. We just haven't
optimized visitdir() for regular (non-include, non-exclude) patterns
yet.

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.