hgext/win32text.py
author Manuel Jacob <me@manueljacob.de>
Wed, 24 Jun 2020 14:44:21 +0200
changeset 44998 f2de8f31cb59
parent 43105 649d3ac37a12
child 45942 89a2afe31e82
permissions -rw-r--r--
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.

# win32text.py - LF <-> CRLF/CR translation utilities for Windows/Mac users
#
#  Copyright 2005, 2007-2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''perform automatic newline conversion (DEPRECATED)

  Deprecation: The win32text extension requires each user to configure
  the extension again and again for each clone since the configuration
  is not copied when cloning.

  We have therefore made the ``eol`` as an alternative. The ``eol``
  uses a version controlled file for its configuration and each clone
  will therefore use the right settings from the start.

To perform automatic newline conversion, use::

  [extensions]
  win32text =
  [encode]
  ** = cleverencode:
  # or ** = macencode:

  [decode]
  ** = cleverdecode:
  # or ** = macdecode:

If not doing conversion, to make sure you do not commit CRLF/CR by accident::

  [hooks]
  pretxncommit.crlf = python:hgext.win32text.forbidcrlf
  # or pretxncommit.cr = python:hgext.win32text.forbidcr

To do the same check on a server to prevent CRLF/CR from being
pushed or pulled::

  [hooks]
  pretxnchangegroup.crlf = python:hgext.win32text.forbidcrlf
  # or pretxnchangegroup.cr = python:hgext.win32text.forbidcr
'''

from __future__ import absolute_import

import re
from mercurial.i18n import _
from mercurial.node import short
from mercurial import (
    pycompat,
    registrar,
)
from mercurial.utils import stringutil

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'

configtable = {}
configitem = registrar.configitem(configtable)

configitem(
    b'win32text', b'warn', default=True,
)

# regexp for single LF without CR preceding.
re_single_lf = re.compile(b'(^|[^\r])\n', re.MULTILINE)

newlinestr = {b'\r\n': b'CRLF', b'\r': b'CR'}
filterstr = {b'\r\n': b'clever', b'\r': b'mac'}


def checknewline(s, newline, ui=None, repo=None, filename=None):
    # warn if already has 'newline' in repository.
    # it might cause unexpected eol conversion.
    # see issue 302:
    #   https://bz.mercurial-scm.org/302
    if newline in s and ui and filename and repo:
        ui.warn(
            _(
                b'WARNING: %s already has %s line endings\n'
                b'and does not need EOL conversion by the win32text plugin.\n'
                b'Before your next commit, please reconsider your '
                b'encode/decode settings in \nMercurial.ini or %s.\n'
            )
            % (filename, newlinestr[newline], repo.vfs.join(b'hgrc'))
        )


def dumbdecode(s, cmd, **kwargs):
    checknewline(s, b'\r\n', **kwargs)
    # replace single LF to CRLF
    return re_single_lf.sub(b'\\1\r\n', s)


def dumbencode(s, cmd):
    return s.replace(b'\r\n', b'\n')


def macdumbdecode(s, cmd, **kwargs):
    checknewline(s, b'\r', **kwargs)
    return s.replace(b'\n', b'\r')


def macdumbencode(s, cmd):
    return s.replace(b'\r', b'\n')


def cleverdecode(s, cmd, **kwargs):
    if not stringutil.binary(s):
        return dumbdecode(s, cmd, **kwargs)
    return s


def cleverencode(s, cmd):
    if not stringutil.binary(s):
        return dumbencode(s, cmd)
    return s


def macdecode(s, cmd, **kwargs):
    if not stringutil.binary(s):
        return macdumbdecode(s, cmd, **kwargs)
    return s


def macencode(s, cmd):
    if not stringutil.binary(s):
        return macdumbencode(s, cmd)
    return s


_filters = {
    b'dumbdecode:': dumbdecode,
    b'dumbencode:': dumbencode,
    b'cleverdecode:': cleverdecode,
    b'cleverencode:': cleverencode,
    b'macdumbdecode:': macdumbdecode,
    b'macdumbencode:': macdumbencode,
    b'macdecode:': macdecode,
    b'macencode:': macencode,
}


def forbidnewline(ui, repo, hooktype, node, newline, **kwargs):
    halt = False
    seen = set()
    # we try to walk changesets in reverse order from newest to
    # oldest, so that if we see a file multiple times, we take the
    # newest version as canonical. this prevents us from blocking a
    # changegroup that contains an unacceptable commit followed later
    # by a commit that fixes the problem.
    tip = repo[b'tip']
    for rev in pycompat.xrange(
        repo.changelog.tiprev(), repo[node].rev() - 1, -1
    ):
        c = repo[rev]
        for f in c.files():
            if f in seen or f not in tip or f not in c:
                continue
            seen.add(f)
            data = c[f].data()
            if not stringutil.binary(data) and newline in data:
                if not halt:
                    ui.warn(
                        _(
                            b'attempt to commit or push text file(s) '
                            b'using %s line endings\n'
                        )
                        % newlinestr[newline]
                    )
                ui.warn(_(b'in %s: %s\n') % (short(c.node()), f))
                halt = True
    if halt and hooktype == b'pretxnchangegroup':
        crlf = newlinestr[newline].lower()
        filter = filterstr[newline]
        ui.warn(
            _(
                b'\nTo prevent this mistake in your local repository,\n'
                b'add to Mercurial.ini or .hg/hgrc:\n'
                b'\n'
                b'[hooks]\n'
                b'pretxncommit.%s = python:hgext.win32text.forbid%s\n'
                b'\n'
                b'and also consider adding:\n'
                b'\n'
                b'[extensions]\n'
                b'win32text =\n'
                b'[encode]\n'
                b'** = %sencode:\n'
                b'[decode]\n'
                b'** = %sdecode:\n'
            )
            % (crlf, crlf, filter, filter)
        )
    return halt


def forbidcrlf(ui, repo, hooktype, node, **kwargs):
    return forbidnewline(ui, repo, hooktype, node, b'\r\n', **kwargs)


def forbidcr(ui, repo, hooktype, node, **kwargs):
    return forbidnewline(ui, repo, hooktype, node, b'\r', **kwargs)


def reposetup(ui, repo):
    if not repo.local():
        return
    for name, fn in pycompat.iteritems(_filters):
        repo.adddatafilter(name, fn)


def extsetup(ui):
    # deprecated config: win32text.warn
    if ui.configbool(b'win32text', b'warn'):
        ui.warn(
            _(
                b"win32text is deprecated: "
                b"https://mercurial-scm.org/wiki/Win32TextExtension\n"
            )
        )