tests/test-wireproto.py

fsmonitor: match watchman and filesystem encoding

watchman's paths encoding can differ from filesystem encoding. For example,
on Windows, it's always utf-8.

Before this patch, on Windows, mismatch in path comparison between fsmonitor
state and osutil.statfiles would yield a clean status for added/modified files.

In addition to status reporting wrong results, this leads to files being
discarded from changesets while doing history editing operations such as rebase.

Benchmark:

There is a little overhead at module import:
python -m timeit "import hgext.fsmonitor"
Windows before patch: 1000000 loops, best of 3: 0.563 usec per loop
Windows after patch: 1000000 loops, best of 3: 0.583 usec per loop
Linx before patch: 1000000 loops, best of 3: 0.579 usec per loop
Linux after patch: 1000000 loops, best of 3: 0.588 usec per loop

10000 calls to _watchmantofsencoding:
python -m timeit -s "from hgext.fsmonitor import _watchmantofsencoding, _fixencoding" "fname = '/path/to/file'" "for i in range(10000):" "    if _fixencoding: fname = _watchmantofsencoding(fname)"
Windows (_fixencoding is True): 100 loops, best of 3: 19.5 msec per loop
Linux (_fixencoding is False): 100 loops, best of 3: 3.08 msec per loop

from __future__ import absolute_import, print_function

from mercurial import (
    util,
    wireproto,
)
stringio = util.stringio

class proto(object):
    def __init__(self, args):
        self.args = args
    def getargs(self, spec):
        args = self.args
        args.setdefault('*', {})
        names = spec.split()
        return [args[n] for n in names]

class clientpeer(wireproto.wirepeer):
    def __init__(self, serverrepo):
        self.serverrepo = serverrepo

    def _capabilities(self):
        return ['batch']

    def _call(self, cmd, **args):
        return wireproto.dispatch(self.serverrepo, proto(args), cmd)

    def _callstream(self, cmd, **args):
        return stringio(self._call(cmd, **args))

    @wireproto.batchable
    def greet(self, name):
        f = wireproto.future()
        yield {'name': mangle(name)}, f
        yield unmangle(f.value)

class serverrepo(object):
    def greet(self, name):
        return "Hello, " + name

    def filtered(self, name):
        return self

def mangle(s):
    return ''.join(chr(ord(c) + 1) for c in s)
def unmangle(s):
    return ''.join(chr(ord(c) - 1) for c in s)

def greet(repo, proto, name):
    return mangle(repo.greet(unmangle(name)))

wireproto.commands['greet'] = (greet, 'name',)

srv = serverrepo()
clt = clientpeer(srv)

print(clt.greet("Foobar"))
b = clt.batch()
fs = [b.greet(s) for s in ["Fo, =;:<o", "Bar"]]
b.submit()
print([f.value for f in fs])