rust-node: binary Node ID and conversion utilities
The choice of type makes sure that a `Node` has the exact
wanted size. We'll use a different type for prefixes.
Added dependency: hexadecimal conversion relies on the
`hex` crate.
The fact that sooner or later Mercurial is going to need
to change its hash sizes has been taken strongly in
consideration:
- the hash length is a constant, but that is not directly
exposed to callers. Changing the value of that constant
is the only thing to do to change the hash length (even
in unit tests)
- the code could be adapted to support several sizes of hashes,
if that turned out to be useful. To that effect, only the
size of a given `Node` is exposed in the public API.
- callers not involved in initial computation, I/O and FFI
are able to operate without a priori assumptions on the hash
size. The traits `FromHex` and `ToHex` have not been directly
implemented, so that the doc-comments explaining these
restrictions would stay really visible in `cargo doc`
Differential Revision: https://phab.mercurial-scm.org/D7788
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')