[stgit] / stgit / gitmergeonefile.py

"""Performs a 3-way merge for GIT files
"""

__copyright__ = """
Copyright (C) 2006, Catalin Marinas <catalin.marinas@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""

import sys, os
from stgit.exception import *
from stgit import basedir
from stgit.config import config, file_extensions, ConfigOption
from stgit.utils import append_string
from stgit.out import *
from stgit.run import *

class GitMergeException(StgException):
    pass


#
# Options
#
merger = ConfigOption('stgit', 'merger')
keeporig = ConfigOption('stgit', 'keeporig')

#
# Utility functions
#
def __str2none(x):
    if x == '':
        return None
    else:
        return x

class MRun(Run):
    exc = GitMergeException # use a custom exception class on errors

def __checkout_files(orig_hash, file1_hash, file2_hash,
                     path,
                     orig_mode, file1_mode, file2_mode):
    """Check out the files passed as arguments
    """
    global orig, src1, src2

    extensions = file_extensions()

    if orig_hash:
        orig = path + extensions['ancestor']
        tmp = MRun('git', 'unpack-file', orig_hash).output_one_line()
        os.chmod(tmp, int(orig_mode, 8))
        os.renames(tmp, orig)
    if file1_hash:
        src1 = path + extensions['current']
        tmp = MRun('git', 'unpack-file', file1_hash).output_one_line()
        os.chmod(tmp, int(file1_mode, 8))
        os.renames(tmp, src1)
    if file2_hash:
        src2 = path + extensions['patched']
        tmp = MRun('git', 'unpack-file', file2_hash).output_one_line()
        os.chmod(tmp, int(file2_mode, 8))
        os.renames(tmp, src2)

    if file1_hash and not os.path.exists(path):
        # the current file might be removed by GIT when it is a new
        # file added in both branches. Just re-generate it
        tmp = MRun('git', 'unpack-file', file1_hash).output_one_line()
        os.chmod(tmp, int(file1_mode, 8))
        os.renames(tmp, path)

def __remove_files(orig_hash, file1_hash, file2_hash):
    """Remove any temporary files
    """
    if orig_hash:
        os.remove(orig)
    if file1_hash:
        os.remove(src1)
    if file2_hash:
        os.remove(src2)

def __conflict(path):
    """Write the conflict file for the 'path' variable and exit
    """
    append_string(os.path.join(basedir.get(), 'conflicts'), path)


def interactive_merge(filename):
    """Run the interactive merger on the given file. Note that the
    index should not have any conflicts.
    """
    extensions = file_extensions()

    ancestor = filename + extensions['ancestor']
    current = filename + extensions['current']
    patched = filename + extensions['patched']

    if os.path.isfile(ancestor):
        three_way = True
        files_dict = {'branch1': current,
                      'ancestor': ancestor,
                      'branch2': patched,
                      'output': filename}
        imerger = config.get('stgit.i3merge')
    else:
        three_way = False
        files_dict = {'branch1': current,
                      'branch2': patched,
                      'output': filename}
        imerger = config.get('stgit.i2merge')

    if not imerger:
        raise GitMergeException, 'No interactive merge command configured'

    # check whether we have all the files for the merge
    for fn in [filename, current, patched]:
        if not os.path.isfile(fn):
            raise GitMergeException, \
                  'Cannot run the interactive merge: "%s" missing' % fn

    mtime = os.path.getmtime(filename)

    out.info('Trying the interactive %s merge'
             % (three_way and 'three-way' or 'two-way'))

    err = os.system(imerger % files_dict)
    if err != 0:
        raise GitMergeException, 'The interactive merge failed: %d' % err
    if not os.path.isfile(filename):
        raise GitMergeException, 'The "%s" file is missing' % filename
    if mtime == os.path.getmtime(filename):
        raise GitMergeException, 'The "%s" file was not modified' % filename


#
# Main algorithm
#
def merge(orig_hash, file1_hash, file2_hash,
          path,
          orig_mode, file1_mode, file2_mode):
    """Three-way merge for one file algorithm
    """
    __checkout_files(orig_hash, file1_hash, file2_hash,
                     path,
                     orig_mode, file1_mode, file2_mode)

    # file exists in origin
    if orig_hash:
        # modified in both
        if file1_hash and file2_hash:
            # if modes are the same (git-read-tree probably dealt with it)
            if file1_hash == file2_hash:
                if os.system('git update-index --cacheinfo %s %s %s'
                             % (file1_mode, file1_hash, path)) != 0:
                    out.error('git update-index failed')
                    __conflict(path)
                    return 1
                if os.system('git checkout-index -u -f -- %s' % path):
                    out.error('git checkout-index failed')
                    __conflict(path)
                    return 1
                if file1_mode != file2_mode:
                    out.error('File added in both, permissions conflict')
                    __conflict(path)
                    return 1
            # 3-way merge
            else:
                merge_ok = os.system(str(merger) % {'branch1': src1,
                                                    'ancestor': orig,
                                                    'branch2': src2,
                                                    'output': path }) == 0

                if merge_ok:
                    os.system('git update-index -- %s' % path)
                    __remove_files(orig_hash, file1_hash, file2_hash)
                    return 0
                else:
                    out.error('Three-way merge tool failed for file "%s"'
                              % path)
                    # reset the cache to the first branch
                    os.system('git update-index --cacheinfo %s %s %s'
                              % (file1_mode, file1_hash, path))

                    if config.get('stgit.autoimerge') == 'yes':
                        try:
                            interactive_merge(path)
                        except GitMergeException, ex:
                            # interactive merge failed
                            out.error(str(ex))
                            if str(keeporig) != 'yes':
                                __remove_files(orig_hash, file1_hash,
                                               file2_hash)
                            __conflict(path)
                            return 1
                        # successful interactive merge
                        os.system('git update-index -- %s' % path)
                        __remove_files(orig_hash, file1_hash, file2_hash)
                        return 0
                    else:
                        # no interactive merge, just mark it as conflict
                        if str(keeporig) != 'yes':
                            __remove_files(orig_hash, file1_hash, file2_hash)
                        __conflict(path)
                        return 1

        # file deleted in both or deleted in one and unchanged in the other
        elif not (file1_hash or file2_hash) \
               or file1_hash == orig_hash or file2_hash == orig_hash:
            if os.path.exists(path):
                os.remove(path)
            __remove_files(orig_hash, file1_hash, file2_hash)
            return os.system('git update-index --remove -- %s' % path)
        # file deleted in one and changed in the other
        else:
            # Do something here - we must at least merge the entry in
            # the cache, instead of leaving it in U(nmerged) state. In
            # fact, stg resolved does not handle that.

            # Do the same thing cogito does - remove the file in any case.
            os.system('git update-index --remove -- %s' % path)

            #if file1_hash:
                ## file deleted upstream and changed in the patch. The
                ## patch is probably going to move the changes
                ## elsewhere.

                #os.system('git update-index --remove -- %s' % path)
            #else:
                ## file deleted in the patch and changed upstream. We
                ## could re-delete it, but for now leave it there -
                ## and let the user check if he still wants to remove
                ## the file.

                ## reset the cache to the first branch
                #os.system('git update-index --cacheinfo %s %s %s'
                #          % (file1_mode, file1_hash, path))
            __conflict(path)
            return 1

    # file does not exist in origin
    else:
        # file added in both
        if file1_hash and file2_hash:
            # files are the same
            if file1_hash == file2_hash:
                if os.system('git update-index --add --cacheinfo %s %s %s'
                             % (file1_mode, file1_hash, path)) != 0:
                    out.error('git update-index failed')
                    __conflict(path)
                    return 1
                if os.system('git checkout-index -u -f -- %s' % path):
                    out.error('git checkout-index failed')
                    __conflict(path)
                    return 1
                if file1_mode != file2_mode:
                    out.error('File "s" added in both, permissions conflict'
                              % path)
                    __conflict(path)
                    return 1
            # files added in both but different
            else:
                out.error('File "%s" added in branches but different' % path)
                # reset the cache to the first branch
                os.system('git update-index --cacheinfo %s %s %s'
                          % (file1_mode, file1_hash, path))

                if config.get('stgit.autoimerge') == 'yes':
                    try:
                        interactive_merge(path)
                    except GitMergeException, ex:
                        # interactive merge failed
                        out.error(str(ex))
                        if str(keeporig) != 'yes':
                            __remove_files(orig_hash, file1_hash,
                                           file2_hash)
                        __conflict(path)
                        return 1
                    # successful interactive merge
                    os.system('git update-index -- %s' % path)
                    __remove_files(orig_hash, file1_hash, file2_hash)
                    return 0
                else:
                    # no interactive merge, just mark it as conflict
                    if str(keeporig) != 'yes':
                        __remove_files(orig_hash, file1_hash, file2_hash)
                    __conflict(path)
                    return 1
        # file added in one
        elif file1_hash or file2_hash:
            if file1_hash:
                mode = file1_mode
                obj = file1_hash
            else:
                mode = file2_mode
                obj = file2_hash
            if os.system('git update-index --add --cacheinfo %s %s %s'
                         % (mode, obj, path)) != 0:
                out.error('git update-index failed')
                __conflict(path)
                return 1
            __remove_files(orig_hash, file1_hash, file2_hash)
            return os.system('git checkout-index -u -f -- %s' % path)

    # Unhandled case
    out.error('Unhandled merge conflict: "%s" "%s" "%s" "%s" "%s" "%s" "%s"'
              % (orig_hash, file1_hash, file2_hash,
                 path,
                 orig_mode, file1_mode, file2_mode))
    __conflict(path)
    return 1
Commit	Line	Data
3659ef88 CM	1	"""Performs a 3-way merge for GIT files
	2	"""
	3
	4	__copyright__ = """
	5	Copyright (C) 2006, Catalin Marinas <catalin.marinas@gmail.com>
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License version 2 as
	9	published by the Free Software Foundation.
	10
	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	"""
	20
	21	import sys, os
87c93eab	22	from stgit.exception import *
170f576b	23	from stgit import basedir
f7ed76a9	24	from stgit.config import config, file_extensions, ConfigOption
5e888f30 KH	25	from stgit.utils import append_string
5e888f30 KH	26	from stgit.out import *
f0de3f92	27	from stgit.run import *
3659ef88	28
87c93eab	29	class GitMergeException(StgException):
3659ef88 CM	30	pass
	31
	32
	33	#
	34	# Options
	35	#
eee7283e CM	36	merger = ConfigOption('stgit', 'merger')
eee7283e CM	37	keeporig = ConfigOption('stgit', 'keeporig')
3659ef88 CM	38
	39	#
	40	# Utility functions
	41	#
	42	def __str2none(x):
	43	if x == '':
	44	return None
	45	else:
	46	return x
	47
f0de3f92 KH	48	class MRun(Run):
f0de3f92 KH	49	exc = GitMergeException # use a custom exception class on errors
3659ef88 CM	50
	51	def __checkout_files(orig_hash, file1_hash, file2_hash,
	52	path,
	53	orig_mode, file1_mode, file2_mode):
	54	"""Check out the files passed as arguments
	55	"""
	56	global orig, src1, src2
	57
1e075406 CM	58	extensions = file_extensions()
1e075406 CM	59
3659ef88	60	if orig_hash:
1e075406	61	orig = path + extensions['ancestor']
1576d681	62	tmp = MRun('git', 'unpack-file', orig_hash).output_one_line()
3659ef88 CM	63	os.chmod(tmp, int(orig_mode, 8))
	64	os.renames(tmp, orig)
	65	if file1_hash:
1e075406	66	src1 = path + extensions['current']
1576d681	67	tmp = MRun('git', 'unpack-file', file1_hash).output_one_line()
3659ef88 CM	68	os.chmod(tmp, int(file1_mode, 8))
	69	os.renames(tmp, src1)
	70	if file2_hash:
1e075406	71	src2 = path + extensions['patched']
1576d681	72	tmp = MRun('git', 'unpack-file', file2_hash).output_one_line()
3659ef88 CM	73	os.chmod(tmp, int(file2_mode, 8))
	74	os.renames(tmp, src2)
	75
8d415553 CM	76	if file1_hash and not os.path.exists(path):
	77	# the current file might be removed by GIT when it is a new
	78	# file added in both branches. Just re-generate it
1576d681	79	tmp = MRun('git', 'unpack-file', file1_hash).output_one_line()
8d415553 CM	80	os.chmod(tmp, int(file1_mode, 8))
	81	os.renames(tmp, path)
	82
3659ef88 CM	83	def __remove_files(orig_hash, file1_hash, file2_hash):
	84	"""Remove any temporary files
	85	"""
	86	if orig_hash:
	87	os.remove(orig)
	88	if file1_hash:
	89	os.remove(src1)
	90	if file2_hash:
	91	os.remove(src2)
3659ef88	92
3659ef88 CM	93	def __conflict(path):
	94	"""Write the conflict file for the 'path' variable and exit
	95	"""
170f576b	96	append_string(os.path.join(basedir.get(), 'conflicts'), path)
3659ef88 CM	97
3659ef88 CM	98
f7ed76a9 CM	99	def interactive_merge(filename):
	100	"""Run the interactive merger on the given file. Note that the
	101	index should not have any conflicts.
	102	"""
f7ed76a9 CM	103	extensions = file_extensions()
	104
	105	ancestor = filename + extensions['ancestor']
	106	current = filename + extensions['current']
	107	patched = filename + extensions['patched']
	108
b6e961f2 CM	109	if os.path.isfile(ancestor):
	110	three_way = True
	111	files_dict = {'branch1': current,
	112	'ancestor': ancestor,
	113	'branch2': patched,
	114	'output': filename}
	115	imerger = config.get('stgit.i3merge')
	116	else:
	117	three_way = False
	118	files_dict = {'branch1': current,
	119	'branch2': patched,
	120	'output': filename}
	121	imerger = config.get('stgit.i2merge')
	122
	123	if not imerger:
	124	raise GitMergeException, 'No interactive merge command configured'
	125
	126	# check whether we have all the files for the merge
	127	for fn in [filename, current, patched]:
f7ed76a9 CM	128	if not os.path.isfile(fn):
f7ed76a9 CM	129	raise GitMergeException, \
b6e961f2	130	'Cannot run the interactive merge: "%s" missing' % fn
f7ed76a9 CM	131
	132	mtime = os.path.getmtime(filename)
	133
27ac2b7e KH	134	out.info('Trying the interactive %s merge'
27ac2b7e KH	135	% (three_way and 'three-way' or 'two-way'))
f7ed76a9	136
b6e961f2	137	err = os.system(imerger % files_dict)
f7ed76a9 CM	138	if err != 0:
	139	raise GitMergeException, 'The interactive merge failed: %d' % err
	140	if not os.path.isfile(filename):
	141	raise GitMergeException, 'The "%s" file is missing' % filename
	142	if mtime == os.path.getmtime(filename):
	143	raise GitMergeException, 'The "%s" file was not modified' % filename
	144
	145
3659ef88 CM	146	#
	147	# Main algorithm
	148	#
	149	def merge(orig_hash, file1_hash, file2_hash,
	150	path,
	151	orig_mode, file1_mode, file2_mode):
	152	"""Three-way merge for one file algorithm
	153	"""
	154	__checkout_files(orig_hash, file1_hash, file2_hash,
	155	path,
	156	orig_mode, file1_mode, file2_mode)
	157
	158	# file exists in origin
	159	if orig_hash:
	160	# modified in both
	161	if file1_hash and file2_hash:
	162	# if modes are the same (git-read-tree probably dealt with it)
	163	if file1_hash == file2_hash:
1576d681	164	if os.system('git update-index --cacheinfo %s %s %s'
3659ef88	165	% (file1_mode, file1_hash, path)) != 0:
1576d681	166	out.error('git update-index failed')
3659ef88 CM	167	__conflict(path)
3659ef88 CM	168	return 1
1576d681 CM	169	if os.system('git checkout-index -u -f -- %s' % path):
1576d681 CM	170	out.error('git checkout-index failed')
3659ef88 CM	171	__conflict(path)
	172	return 1
	173	if file1_mode != file2_mode:
27ac2b7e	174	out.error('File added in both, permissions conflict')
3659ef88 CM	175	__conflict(path)
	176	return 1
	177	# 3-way merge
	178	else:
5b99888b CM	179	merge_ok = os.system(str(merger) % {'branch1': src1,
	180	'ancestor': orig,
	181	'branch2': src2,
	182	'output': path }) == 0
3659ef88 CM	183
3659ef88 CM	184	if merge_ok:
1576d681	185	os.system('git update-index -- %s' % path)
3659ef88 CM	186	__remove_files(orig_hash, file1_hash, file2_hash)
	187	return 0
	188	else:
27ac2b7e KH	189	out.error('Three-way merge tool failed for file "%s"'
27ac2b7e KH	190	% path)
3659ef88	191	# reset the cache to the first branch
1576d681	192	os.system('git update-index --cacheinfo %s %s %s'
3659ef88	193	% (file1_mode, file1_hash, path))
f7ed76a9	194
c73e63b7	195	if config.get('stgit.autoimerge') == 'yes':
f7ed76a9 CM	196	try:
	197	interactive_merge(path)
	198	except GitMergeException, ex:
	199	# interactive merge failed
f0b5d4dd	200	out.error(str(ex))
f7ed76a9 CM	201	if str(keeporig) != 'yes':
	202	__remove_files(orig_hash, file1_hash,
	203	file2_hash)
	204	__conflict(path)
	205	return 1
	206	# successful interactive merge
1576d681	207	os.system('git update-index -- %s' % path)
3659ef88	208	__remove_files(orig_hash, file1_hash, file2_hash)
f7ed76a9 CM	209	return 0
	210	else:
	211	# no interactive merge, just mark it as conflict
	212	if str(keeporig) != 'yes':
	213	__remove_files(orig_hash, file1_hash, file2_hash)
	214	__conflict(path)
	215	return 1
	216
3659ef88 CM	217	# file deleted in both or deleted in one and unchanged in the other
	218	elif not (file1_hash or file2_hash) \
	219	or file1_hash == orig_hash or file2_hash == orig_hash:
	220	if os.path.exists(path):
	221	os.remove(path)
	222	__remove_files(orig_hash, file1_hash, file2_hash)
1576d681	223	return os.system('git update-index --remove -- %s' % path)
3659ef88 CM	224	# file deleted in one and changed in the other
	225	else:
	226	# Do something here - we must at least merge the entry in
	227	# the cache, instead of leaving it in U(nmerged) state. In
	228	# fact, stg resolved does not handle that.
	229
	230	# Do the same thing cogito does - remove the file in any case.
1576d681	231	os.system('git update-index --remove -- %s' % path)
3659ef88 CM	232
	233	#if file1_hash:
	234	## file deleted upstream and changed in the patch. The
	235	## patch is probably going to move the changes
	236	## elsewhere.
	237
1576d681	238	#os.system('git update-index --remove -- %s' % path)
3659ef88 CM	239	#else:
	240	## file deleted in the patch and changed upstream. We
	241	## could re-delete it, but for now leave it there -
	242	## and let the user check if he still wants to remove
	243	## the file.
	244
	245	## reset the cache to the first branch
1576d681	246	#os.system('git update-index --cacheinfo %s %s %s'
3659ef88 CM	247	# % (file1_mode, file1_hash, path))
	248	__conflict(path)
	249	return 1
	250
	251	# file does not exist in origin
	252	else:
	253	# file added in both
	254	if file1_hash and file2_hash:
	255	# files are the same
	256	if file1_hash == file2_hash:
1576d681	257	if os.system('git update-index --add --cacheinfo %s %s %s'
3659ef88	258	% (file1_mode, file1_hash, path)) != 0:
1576d681	259	out.error('git update-index failed')
3659ef88 CM	260	__conflict(path)
3659ef88 CM	261	return 1
1576d681 CM	262	if os.system('git checkout-index -u -f -- %s' % path):
1576d681 CM	263	out.error('git checkout-index failed')
3659ef88 CM	264	__conflict(path)
	265	return 1
	266	if file1_mode != file2_mode:
27ac2b7e KH	267	out.error('File "s" added in both, permissions conflict'
27ac2b7e KH	268	% path)
3659ef88 CM	269	__conflict(path)
3659ef88 CM	270	return 1
b6e961f2	271	# files added in both but different
3659ef88	272	else:
27ac2b7e	273	out.error('File "%s" added in branches but different' % path)
b6e961f2	274	# reset the cache to the first branch
1576d681	275	os.system('git update-index --cacheinfo %s %s %s'
b6e961f2 CM	276	% (file1_mode, file1_hash, path))
	277
	278	if config.get('stgit.autoimerge') == 'yes':
	279	try:
	280	interactive_merge(path)
	281	except GitMergeException, ex:
	282	# interactive merge failed
f0b5d4dd	283	out.error(str(ex))
b6e961f2 CM	284	if str(keeporig) != 'yes':
	285	__remove_files(orig_hash, file1_hash,
	286	file2_hash)
	287	__conflict(path)
	288	return 1
	289	# successful interactive merge
1576d681	290	os.system('git update-index -- %s' % path)
b6e961f2 CM	291	__remove_files(orig_hash, file1_hash, file2_hash)
	292	return 0
	293	else:
	294	# no interactive merge, just mark it as conflict
	295	if str(keeporig) != 'yes':
	296	__remove_files(orig_hash, file1_hash, file2_hash)
	297	__conflict(path)
	298	return 1
3659ef88 CM	299	# file added in one
	300	elif file1_hash or file2_hash:
	301	if file1_hash:
	302	mode = file1_mode
	303	obj = file1_hash
	304	else:
	305	mode = file2_mode
	306	obj = file2_hash
1576d681	307	if os.system('git update-index --add --cacheinfo %s %s %s'
3659ef88	308	% (mode, obj, path)) != 0:
1576d681	309	out.error('git update-index failed')
3659ef88 CM	310	__conflict(path)
	311	return 1
	312	__remove_files(orig_hash, file1_hash, file2_hash)
1576d681	313	return os.system('git checkout-index -u -f -- %s' % path)
3659ef88 CM	314
3659ef88 CM	315	# Unhandled case
27ac2b7e KH	316	out.error('Unhandled merge conflict: "%s" "%s" "%s" "%s" "%s" "%s" "%s"'
	317	% (orig_hash, file1_hash, file2_hash,
	318	path,
	319	orig_mode, file1_mode, file2_mode))
3659ef88 CM	320	__conflict(path)
3659ef88 CM	321	return 1