sapling/hgext/win32text.py

# 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 import registrar, util
from mercurial.i18n import _
from mercurial.node import short


# 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 = "ships-with-hg-core"

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

configitem("win32text", "warn", default=True)

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

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

try:
    xrange(0)
except NameError:
    xrange = range


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(
            _(
                "WARNING: %s already has %s line endings\n"
                "and does not need EOL conversion by the win32text plugin.\n"
                "Before your next commit, please reconsider your "
                "encode/decode settings in \nMercurial.ini or %s.\n"
            )
            % (filename, newlinestr[newline], repo.vfs.join("hgrc"))
        )


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


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


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


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


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


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


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


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


_filters = {
    "dumbdecode:": dumbdecode,
    "dumbencode:": dumbencode,
    "cleverdecode:": cleverdecode,
    "cleverencode:": cleverencode,
    "macdumbdecode:": macdumbdecode,
    "macdumbencode:": macdumbencode,
    "macdecode:": macdecode,
    "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["tip"]
    for rev in xrange(len(repo) - 1, 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 util.binary(data) and newline in data:
                if not halt:
                    ui.warn(
                        _(
                            "attempt to commit or push text file(s) "
                            "using %s line endings\n"
                        )
                        % newlinestr[newline]
                    )
                ui.warn(_("in %s: %s\n") % (short(c.node()), f))
                halt = True
    if halt and hooktype == "pretxnchangegroup":
        crlf = newlinestr[newline].lower()
        filter = filterstr[newline]
        ui.warn(
            _(
                "\nTo prevent this mistake in your local repository,\n"
                "add to Mercurial.ini or .hg/hgrc:\n"
                "\n"
                "[hooks]\n"
                "pretxncommit.%s = python:hgext.win32text.forbid%s\n"
                "\n"
                "and also consider adding:\n"
                "\n"
                "[extensions]\n"
                "win32text =\n"
                "[encode]\n"
                "** = %sencode:\n"
                "[decode]\n"
                "** = %sdecode:\n"
            )
            % (crlf, crlf, filter, filter)
        )
    return halt


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


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


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


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