~brz/brz-debian/byoci

#!/usr/bin/env python

# -*- coding: utf-8 -*-

# Copyright ? 2008 Canonical Ltd.

# Author: Scott James Remnant <scott@ubuntu.com>.

# Hacked up by: Bryce Harrington <bryce@ubuntu.com>

#

# This program is free software: you can redistribute it and/or modify

# it under the terms of version 3 of the GNU General Public License as

# published by the Free Software Foundation.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from __future__ import absolute_import

import errno

import logging

import os.path

import re

import shutil

import subprocess

import tempfile

from ... import (

    merge,

    osutils,

    )

# A logger in the 'bzr' hierarchy.  By default messages will be propagated to

# the standard bzr logger, but tests can easily intercept just this logger if

# they wish.

_logger = logging.getLogger('breezy.plugins.debian.merge_changelog')

class ChangeLogFileMerge(merge.ConfigurableFileMerger):

    name_prefix = 'deb_changelog'

    default_files = ['debian/changelog']

    def merge_text(self, params):

        return merge_changelog(params.this_lines, params.other_lines,

            params.base_lines)

def merge_changelog(this_lines, other_lines, base_lines=[]):

    """Merge a changelog file."""

    # Write the BASE, THIS and OTHER versions to files in a temporary

    # directory, and use dpkg-mergechangelogs to merge them.

    tmpdir = tempfile.mkdtemp('deb_changelog_merge')

    try:

        def writelines(filename, lines):

            with open(filename, 'w') as f:

                for line in lines:

                    f.write(line)

        base_filename = os.path.join(tmpdir, 'changelog.base')

        this_filename = os.path.join(tmpdir, 'changelog.this')

        other_filename = os.path.join(tmpdir, 'changelog.other')

        writelines(base_filename, base_lines)

        writelines(this_filename, this_lines)

        writelines(other_filename, other_lines)

        try:

            proc = subprocess.Popen(['dpkg-mergechangelogs', base_filename,

                this_filename, other_filename], stdout=subprocess.PIPE,

                stderr=subprocess.PIPE)

        except OSError, e:

            if e.errno == errno.ENOENT:

                # No dpkg-mergechangelogs command available

                return 'not_applicable', ''

            raise

        stdout, stderr = proc.communicate()

        retcode = proc.returncode

        if stderr:

            # Relay the warning from dpkg-mergechangelogs to the user.  We

            # don't decorate the messages at all, as dpkg-mergechangelogs

            # warnings are already prefixed with "dpkg-mergechangelogs:

            # warning:" which makes the origin of the messages quite clear.

            encoding = osutils.get_user_encoding()

            # Errors are output using the locale, and log needs unicode.

            _logger.warning('%s', stderr.decode(encoding, "replace"))

        if retcode == 1:

            # dpkg-mergechangelogs reports a conflict.  Unfortunately it uses

            # slightly non-standard conflict markers (<http://pad.lv/815700>:

            # "<<<<<<" rather than "<<<<<<<", i.e. 6 chars instead of 7), so we

            # correct that here to make the results of this plugin as

            # consistent with regular bzr usage as possible.  Note that

            # conflict markers are never valid lines in a changelog file, so

            # it's reasonable for us to assume that any line that looks like a

            # conflict marker is a conflict marker (rather than valid content).

            # At worst a conflicted merge of an invalid changelog file that

            # already contained a non-standard conflict marker will have that

            # conflict marker made standard, which is more like a feature than

            # a bug!

            def replace_func(match_obj):

                match_text = match_obj.group(0)

                return match_text[0] * 7

            stdout = re.sub('(?m)^[<=>]{6}$', replace_func, stdout)

            return 'conflicted', stdout

        elif retcode != 0:

            # dpkg-mergechangelogs exited with an error. There is probably no

            # output at all, but regardless the merge should fall back to

            # another method.

            _logger.warning("dpkg-mergechangelogs failed with status %d", retcode)

            return 'not_applicable', stdout

        else:

            return 'success', stdout

    finally:

        shutil.rmtree(tmpdir)