contrib/casesmash.py

context: get filesadded() and filesremoved() from changeset if configured

This adds the read side for getting the sets of added and removed
files from the changeset extras. I timed this command on the hg repo:

  hg log -T '{rev}\n {files}\n %:{file_mods}\n +{file_adds}\n -{file_dels}\n'

It took 1m21s before and 6.4s after. I also used that command to check
that the result didn't change compared to calculating the values from
the manifests on the fly (it didn't change).

In the mozilla-unified repo, the same command run on
FIREFOX_BETA_58_END::FIREFOX_BETA_59_END went from 29s to 0.67s.

Differential Revision: https://phab.mercurial-scm.org/D6417

from __future__ import absolute_import
import __builtin__
import os
from mercurial import (
    util,
)

def lowerwrap(scope, funcname):
    f = getattr(scope, funcname)
    def wrap(fname, *args, **kwargs):
        d, base = os.path.split(fname)
        try:
            files = os.listdir(d or '.')
        except OSError:
            files = []
        if base in files:
            return f(fname, *args, **kwargs)
        for fn in files:
            if fn.lower() == base.lower():
                return f(os.path.join(d, fn), *args, **kwargs)
        return f(fname, *args, **kwargs)
    scope.__dict__[funcname] = wrap

def normcase(path):
    return path.lower()

os.path.normcase = normcase

for f in 'file open'.split():
    lowerwrap(__builtin__, f)

for f in "chmod chown open lstat stat remove unlink".split():
    lowerwrap(os, f)

for f in "exists lexists".split():
    lowerwrap(os.path, f)

lowerwrap(util, 'posixfile')