[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 import basedir
from stgit.config import config, file_extensions, ConfigOption
from stgit.utils import append_string, out


class GitMergeException(Exception):
    pass


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

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

def __output(cmd):
    f = os.popen(cmd, 'r')
    string = f.readline().rstrip()
    if f.close():
        raise GitMergeException, 'Error: failed to execute "%s"' % cmd
    return string

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 = __output('git-unpack-file %s' % orig_hash)
        os.chmod(tmp, int(orig_mode, 8))
        os.renames(tmp, orig)
    if file1_hash:
        src1 = path + extensions['current']
        tmp = __output('git-unpack-file %s' % file1_hash)
        os.chmod(tmp, int(file1_mode, 8))
        os.renames(tmp, src1)
    if file2_hash:
        src2 = path + extensions['patched']
        tmp = __output('git-unpack-file %s' % file2_hash)
        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 = __output('git-unpack-file %s' % file1_hash)
        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(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(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
170f576b	22	from stgit import basedir
f7ed76a9	23	from stgit.config import config, file_extensions, ConfigOption
27ac2b7e	24	from stgit.utils import append_string, out
3659ef88 CM	25
	26
	27	class GitMergeException(Exception):
	28	pass
	29
	30
	31	#
	32	# Options
	33	#
eee7283e CM	34	merger = ConfigOption('stgit', 'merger')
eee7283e CM	35	keeporig = ConfigOption('stgit', 'keeporig')
3659ef88 CM	36
	37	#
	38	# Utility functions
	39	#
	40	def __str2none(x):
	41	if x == '':
	42	return None
	43	else:
	44	return x
	45
	46	def __output(cmd):
	47	f = os.popen(cmd, 'r')
	48	string = f.readline().rstrip()
	49	if f.close():
	50	raise GitMergeException, 'Error: failed to execute "%s"' % cmd
	51	return string
	52
	53	def __checkout_files(orig_hash, file1_hash, file2_hash,
	54	path,
	55	orig_mode, file1_mode, file2_mode):
	56	"""Check out the files passed as arguments
	57	"""
	58	global orig, src1, src2
	59
1e075406 CM	60	extensions = file_extensions()
1e075406 CM	61
3659ef88	62	if orig_hash:
1e075406	63	orig = path + extensions['ancestor']
3659ef88 CM	64	tmp = __output('git-unpack-file %s' % orig_hash)
	65	os.chmod(tmp, int(orig_mode, 8))
	66	os.renames(tmp, orig)
	67	if file1_hash:
1e075406	68	src1 = path + extensions['current']
3659ef88 CM	69	tmp = __output('git-unpack-file %s' % file1_hash)
	70	os.chmod(tmp, int(file1_mode, 8))
	71	os.renames(tmp, src1)
	72	if file2_hash:
1e075406	73	src2 = path + extensions['patched']
3659ef88 CM	74	tmp = __output('git-unpack-file %s' % file2_hash)
	75	os.chmod(tmp, int(file2_mode, 8))
	76	os.renames(tmp, src2)
	77
8d415553 CM	78	if file1_hash and not os.path.exists(path):
	79	# the current file might be removed by GIT when it is a new
	80	# file added in both branches. Just re-generate it
	81	tmp = __output('git-unpack-file %s' % file1_hash)
	82	os.chmod(tmp, int(file1_mode, 8))
	83	os.renames(tmp, path)
	84
3659ef88 CM	85	def __remove_files(orig_hash, file1_hash, file2_hash):
	86	"""Remove any temporary files
	87	"""
	88	if orig_hash:
	89	os.remove(orig)
	90	if file1_hash:
	91	os.remove(src1)
	92	if file2_hash:
	93	os.remove(src2)
3659ef88	94
3659ef88 CM	95	def __conflict(path):
	96	"""Write the conflict file for the 'path' variable and exit
	97	"""
170f576b	98	append_string(os.path.join(basedir.get(), 'conflicts'), path)
3659ef88 CM	99
3659ef88 CM	100
f7ed76a9 CM	101	def interactive_merge(filename):
	102	"""Run the interactive merger on the given file. Note that the
	103	index should not have any conflicts.
	104	"""
f7ed76a9 CM	105	extensions = file_extensions()
	106
	107	ancestor = filename + extensions['ancestor']
	108	current = filename + extensions['current']
	109	patched = filename + extensions['patched']
	110
b6e961f2 CM	111	if os.path.isfile(ancestor):
	112	three_way = True
	113	files_dict = {'branch1': current,
	114	'ancestor': ancestor,
	115	'branch2': patched,
	116	'output': filename}
	117	imerger = config.get('stgit.i3merge')
	118	else:
	119	three_way = False
	120	files_dict = {'branch1': current,
	121	'branch2': patched,
	122	'output': filename}
	123	imerger = config.get('stgit.i2merge')
	124
	125	if not imerger:
	126	raise GitMergeException, 'No interactive merge command configured'
	127
	128	# check whether we have all the files for the merge
	129	for fn in [filename, current, patched]:
f7ed76a9 CM	130	if not os.path.isfile(fn):
f7ed76a9 CM	131	raise GitMergeException, \
b6e961f2	132	'Cannot run the interactive merge: "%s" missing' % fn
f7ed76a9 CM	133
	134	mtime = os.path.getmtime(filename)
	135
27ac2b7e KH	136	out.info('Trying the interactive %s merge'
27ac2b7e KH	137	% (three_way and 'three-way' or 'two-way'))
f7ed76a9	138
b6e961f2	139	err = os.system(imerger % files_dict)
f7ed76a9 CM	140	if err != 0:
	141	raise GitMergeException, 'The interactive merge failed: %d' % err
	142	if not os.path.isfile(filename):
	143	raise GitMergeException, 'The "%s" file is missing' % filename
	144	if mtime == os.path.getmtime(filename):
	145	raise GitMergeException, 'The "%s" file was not modified' % filename
	146
	147
3659ef88 CM	148	#
	149	# Main algorithm
	150	#
	151	def merge(orig_hash, file1_hash, file2_hash,
	152	path,
	153	orig_mode, file1_mode, file2_mode):
	154	"""Three-way merge for one file algorithm
	155	"""
	156	__checkout_files(orig_hash, file1_hash, file2_hash,
	157	path,
	158	orig_mode, file1_mode, file2_mode)
	159
	160	# file exists in origin
	161	if orig_hash:
	162	# modified in both
	163	if file1_hash and file2_hash:
	164	# if modes are the same (git-read-tree probably dealt with it)
	165	if file1_hash == file2_hash:
	166	if os.system('git-update-index --cacheinfo %s %s %s'
	167	% (file1_mode, file1_hash, path)) != 0:
27ac2b7e	168	out.error('git-update-index failed')
3659ef88 CM	169	__conflict(path)
	170	return 1
	171	if os.system('git-checkout-index -u -f -- %s' % path):
27ac2b7e	172	out.error('git-checkout-index failed')
3659ef88 CM	173	__conflict(path)
	174	return 1
	175	if file1_mode != file2_mode:
27ac2b7e	176	out.error('File added in both, permissions conflict')
3659ef88 CM	177	__conflict(path)
	178	return 1
	179	# 3-way merge
	180	else:
5b99888b CM	181	merge_ok = os.system(str(merger) % {'branch1': src1,
	182	'ancestor': orig,
	183	'branch2': src2,
	184	'output': path }) == 0
3659ef88 CM	185
	186	if merge_ok:
	187	os.system('git-update-index -- %s' % path)
	188	__remove_files(orig_hash, file1_hash, file2_hash)
	189	return 0
	190	else:
27ac2b7e KH	191	out.error('Three-way merge tool failed for file "%s"'
27ac2b7e KH	192	% path)
3659ef88 CM	193	# reset the cache to the first branch
	194	os.system('git-update-index --cacheinfo %s %s %s'
	195	% (file1_mode, file1_hash, path))
f7ed76a9	196
c73e63b7	197	if config.get('stgit.autoimerge') == 'yes':
f7ed76a9 CM	198	try:
	199	interactive_merge(path)
	200	except GitMergeException, ex:
	201	# interactive merge failed
27ac2b7e	202	out.error(ex)
f7ed76a9 CM	203	if str(keeporig) != 'yes':
	204	__remove_files(orig_hash, file1_hash,
	205	file2_hash)
	206	__conflict(path)
	207	return 1
	208	# successful interactive merge
0f4eba6a	209	os.system('git-update-index -- %s' % path)
3659ef88	210	__remove_files(orig_hash, file1_hash, file2_hash)
f7ed76a9 CM	211	return 0
	212	else:
	213	# no interactive merge, just mark it as conflict
	214	if str(keeporig) != 'yes':
	215	__remove_files(orig_hash, file1_hash, file2_hash)
	216	__conflict(path)
	217	return 1
	218
3659ef88 CM	219	# file deleted in both or deleted in one and unchanged in the other
	220	elif not (file1_hash or file2_hash) \
	221	or file1_hash == orig_hash or file2_hash == orig_hash:
	222	if os.path.exists(path):
	223	os.remove(path)
	224	__remove_files(orig_hash, file1_hash, file2_hash)
	225	return os.system('git-update-index --remove -- %s' % path)
	226	# file deleted in one and changed in the other
	227	else:
	228	# Do something here - we must at least merge the entry in
	229	# the cache, instead of leaving it in U(nmerged) state. In
	230	# fact, stg resolved does not handle that.
	231
	232	# Do the same thing cogito does - remove the file in any case.
	233	os.system('git-update-index --remove -- %s' % path)
	234
	235	#if file1_hash:
	236	## file deleted upstream and changed in the patch. The
	237	## patch is probably going to move the changes
	238	## elsewhere.
	239
	240	#os.system('git-update-index --remove -- %s' % path)
	241	#else:
	242	## file deleted in the patch and changed upstream. We
	243	## could re-delete it, but for now leave it there -
	244	## and let the user check if he still wants to remove
	245	## the file.
	246
	247	## reset the cache to the first branch
	248	#os.system('git-update-index --cacheinfo %s %s %s'
	249	# % (file1_mode, file1_hash, path))
	250	__conflict(path)
	251	return 1
	252
	253	# file does not exist in origin
	254	else:
	255	# file added in both
	256	if file1_hash and file2_hash:
	257	# files are the same
	258	if file1_hash == file2_hash:
	259	if os.system('git-update-index --add --cacheinfo %s %s %s'
	260	% (file1_mode, file1_hash, path)) != 0:
27ac2b7e	261	out.error('git-update-index failed')
3659ef88 CM	262	__conflict(path)
	263	return 1
	264	if os.system('git-checkout-index -u -f -- %s' % path):
27ac2b7e	265	out.error('git-checkout-index failed')
3659ef88 CM	266	__conflict(path)
	267	return 1
	268	if file1_mode != file2_mode:
27ac2b7e KH	269	out.error('File "s" added in both, permissions conflict'
27ac2b7e KH	270	% path)
3659ef88 CM	271	__conflict(path)
3659ef88 CM	272	return 1
b6e961f2	273	# files added in both but different
3659ef88	274	else:
27ac2b7e	275	out.error('File "%s" added in branches but different' % path)
b6e961f2 CM	276	# reset the cache to the first branch
	277	os.system('git-update-index --cacheinfo %s %s %s'
	278	% (file1_mode, file1_hash, path))
	279
	280	if config.get('stgit.autoimerge') == 'yes':
	281	try:
	282	interactive_merge(path)
	283	except GitMergeException, ex:
	284	# interactive merge failed
27ac2b7e	285	out.error(ex)
b6e961f2 CM	286	if str(keeporig) != 'yes':
	287	__remove_files(orig_hash, file1_hash,
	288	file2_hash)
	289	__conflict(path)
	290	return 1
	291	# successful interactive merge
	292	os.system('git-update-index -- %s' % path)
	293	__remove_files(orig_hash, file1_hash, file2_hash)
	294	return 0
	295	else:
	296	# no interactive merge, just mark it as conflict
	297	if str(keeporig) != 'yes':
	298	__remove_files(orig_hash, file1_hash, file2_hash)
	299	__conflict(path)
	300	return 1
3659ef88 CM	301	# file added in one
	302	elif file1_hash or file2_hash:
	303	if file1_hash:
	304	mode = file1_mode
	305	obj = file1_hash
	306	else:
	307	mode = file2_mode
	308	obj = file2_hash
	309	if os.system('git-update-index --add --cacheinfo %s %s %s'
	310	% (mode, obj, path)) != 0:
27ac2b7e	311	out.error('git-update-index failed')
3659ef88 CM	312	__conflict(path)
	313	return 1
	314	__remove_files(orig_hash, file1_hash, file2_hash)
	315	return os.system('git-checkout-index -u -f -- %s' % path)
	316
	317	# Unhandled case
27ac2b7e KH	318	out.error('Unhandled merge conflict: "%s" "%s" "%s" "%s" "%s" "%s" "%s"'
	319	% (orig_hash, file1_hash, file2_hash,
	320	path,
	321	orig_mode, file1_mode, file2_mode))
3659ef88 CM	322	__conflict(path)
3659ef88 CM	323	return 1