contrib/benchmarks/revset.py

pycompat: use os.fsencode() to re-encode sys.argv

Historically, the previous code made sense, as Py_EncodeLocale() and
fs.fsencode() could possibly use different encodings. However, this is not the
case anymore for Python 3.2, which uses the locale encoding as the filesystem
encoding (this is not true for later Python versions, but see below). See
https://vstinner.github.io/painful-history-python-filesystem-encoding.html for
a source and more background information.

Using os.fsencode() is safer, as the documentation for sys.argv says that it can
be used to get the original bytes. When doing further changes, the Python
developers will take care that this continues to work.

One concrete case where os.fsencode() is more correct is when enabling Python's
UTF-8 mode. Py_DecodeLocale() will use UTF-8 in this case. Our previous code
would have encoded it using the locale encoding (which might be different),
whereas os.fsencode() will encode it with UTF-8.

Since we don’t claim to support the UTF-8 mode, this is not really a bug and the
patch can go to the default branch. It might be a good idea to not commit this
to the stable branch, as it could in theory introduce regressions.

# revset.py - asv revset benchmarks
#
# Copyright 2016 Logilab SA <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''ASV revset benchmarks generated from contrib/base-revsets.txt

Each revset benchmark is parameterized with variants (first, last, sort, ...)
'''

from __future__ import absolute_import

import os
import string
import sys

from . import basedir, perfbench


def createrevsetbenchmark(baseset, variants=None):
    if variants is None:
        # Default variants
        variants = ["plain", "first", "last", "sort", "sort+first", "sort+last"]
    fname = "track_" + "_".join(
        "".join(
            [c if c in string.digits + string.letters else " " for c in baseset]
        ).split()
    )

    def wrap(fname, baseset):
        @perfbench(name=baseset, params=[("variant", variants)])
        def f(perf, variant):
            revset = baseset
            if variant != "plain":
                for var in variant.split("+"):
                    revset = "%s(%s)" % (var, revset)
            return perf("perfrevset", revset)

        f.__name__ = fname
        return f

    return wrap(fname, baseset)


def initializerevsetbenchmarks():
    mod = sys.modules[__name__]
    with open(os.path.join(basedir, 'contrib', 'base-revsets.txt'), 'rb') as fh:
        for line in fh:
            baseset = line.strip()
            if baseset and not baseset.startswith('#'):
                func = createrevsetbenchmark(baseset)
                setattr(mod, func.__name__, func)


initializerevsetbenchmarks()