mercurial/pycompat.py

tests: escape bytes setting MSB in input of grep for portability

GNU grep (2.21-2 or later) assumes that input is encoded in LC_CTYPE,
and input is binary if it contains byte sequence not valid for that
encoding.

For example, if locale is configured as C, a byte setting most
significant bit (MSB) makes such GNU grep show "Binary file <FILENAME>
matches" message instead of matched lines unintentionally.

This behavior is recognized as a bug, and fixed in GNU grep 2.25-1 or
later. But some distributions are shipped with such buggy version
(e.g. Ubuntu xenial, which is used by launchpad buildbot).

    http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19230
    https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=800670
    http://packages.ubuntu.com/xenial/grep

This causes failure of test-commit-interactive.t, which applies grep
on CP932 byte sequence since 1111e84de635.

But, explicit setting LC_CTYPE for CP932 might cause another problem,
because it can't be assumed that all environment running Mercurial
tests allows arbitrary locale setting.

To resolve this issue, this patch escapes bytes setting MSB in input
of grep.

For this purpose:

  - str.encode('string-escape') isn't useful, because it escapes also
    control code (less than 0x20), and makes EOL handling complicated

  - "f --hexdump" isn't useful, because it isn't line-oriented

  - "sed -n" seems reasonable, but "sed" itself sometimes causes
    portability issue, too (e.g. 900767dfa80d or afb86ee925bf)

This patch is posted with "stable" flag, because 1111e84de635 is on
stable branch.

# pycompat.py - portability shim for python 3
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""Mercurial portability shim for python 3.

This contains aliases to hide python version-specific details from the core.
"""

from __future__ import absolute_import

try:
    import cStringIO as io
    stringio = io.StringIO
except ImportError:
    import io
    stringio = io.StringIO

try:
    import Queue as _queue
    _queue.Queue
except ImportError:
    import queue as _queue
empty = _queue.Empty
queue = _queue.Queue

class _pycompatstub(object):
    pass

def _alias(alias, origin, items):
    """ populate a _pycompatstub

    copies items from origin to alias
    """
    def hgcase(item):
        return item.replace('_', '').lower()
    for item in items:
        try:
            setattr(alias, hgcase(item), getattr(origin, item))
        except AttributeError:
            pass

urlreq = _pycompatstub()
urlerr = _pycompatstub()
try:
    import urllib2
    import urllib
    _alias(urlreq, urllib, (
        "addclosehook",
        "addinfourl",
        "ftpwrapper",
        "pathname2url",
        "quote",
        "splitattr",
        "splitpasswd",
        "splitport",
        "splituser",
        "unquote",
        "url2pathname",
        "urlencode",
        "urlencode",
    ))
    _alias(urlreq, urllib2, (
        "AbstractHTTPHandler",
        "BaseHandler",
        "build_opener",
        "FileHandler",
        "FTPHandler",
        "HTTPBasicAuthHandler",
        "HTTPDigestAuthHandler",
        "HTTPHandler",
        "HTTPPasswordMgrWithDefaultRealm",
        "HTTPSHandler",
        "install_opener",
        "ProxyHandler",
        "Request",
        "urlopen",
    ))
    _alias(urlerr, urllib2, (
        "HTTPError",
        "URLError",
    ))

except ImportError:
    import urllib.request
    _alias(urlreq, urllib.request, (
        "AbstractHTTPHandler",
        "addclosehook",
        "addinfourl",
        "BaseHandler",
        "build_opener",
        "FileHandler",
        "FTPHandler",
        "ftpwrapper",
        "HTTPHandler",
        "HTTPSHandler",
        "install_opener",
        "pathname2url",
        "HTTPBasicAuthHandler",
        "HTTPDigestAuthHandler",
        "ProxyHandler",
        "quote",
        "Request",
        "splitattr",
        "splitpasswd",
        "splitport",
        "splituser",
        "unquote",
        "url2pathname",
        "urlopen",
    ))
    import urllib.error
    _alias(urlerr, urllib.error, (
        "HTTPError",
        "URLError",
    ))

try:
    xrange
except NameError:
    import builtins
    builtins.xrange = range