# Copyright (C) 2010 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
"""Merge logic for news_merge plugin."""
from bzrlib.plugins.news_merge.parser import simple_parse_lines
from bzrlib import merge,merge3
class NewsMerger(merge.ConfigurableFileMerger):
"""Merge bzr NEWS files."""
name_prefix = "news"
def merge_text(self, params):
"""Perform a simple 3-way merge of a bzr NEWS file.
Each section of a bzr NEWS file is essentially an ordered set of bullet
points, so we can simply take a set of bullet points, determine which
bullets to add and which to remove, sort, and reserialize.
"""
# Transform the different versions of the NEWS file into a bunch of
# text lines where each line matches one part of the overall
# structure, e.g. a heading or bullet.
this_lines = list(simple_parse_lines(params.this_lines))
other_lines = list(simple_parse_lines(params.other_lines))
base_lines = list(simple_parse_lines(params.base_lines))
m3 = merge3.Merge3(base_lines, this_lines, other_lines,
allow_objects=True)
result_chunks = []
for group in m3.merge_groups():
if group[0] == 'conflict':
_, base, a, b = group
# Are all the conflicting lines bullets? If so, we can merge
# this.
for line_set in [base, a, b]:
for line in line_set:
if line[0] != 'bullet':
# Something else :(
# Maybe the default merge can cope.
return 'not_applicable', None
# Calculate additions and deletions.
new_in_a = set(a).difference(base)
new_in_b = set(b).difference(base)
all_new = new_in_a.union(new_in_b)
deleted_in_a = set(base).difference(a)
deleted_in_b = set(base).difference(b)
# Combine into the final set of bullet points.
final = all_new.difference(deleted_in_a).difference(
deleted_in_b)
# Sort, and emit.
final = sorted(final, key=sort_key)
result_chunks.extend(final)
else:
result_chunks.extend(group[1])
# Transform the merged elements back into real blocks of lines.
result_lines = '\n\n'.join(chunk[1] for chunk in result_chunks)
return 'success', result_lines
def sort_key(chunk):
return chunk[1].replace('`', '').lower()
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