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branch.py
1
1
# Copyright (C) 2007 Canonical Ltd
2
 
# Copyright (C) 2009 Jelmer Vernooij <jelmer@samba.org>
3
2
#
4
3
# This program is free software; you can redistribute it and/or modify
5
4
# it under the terms of the GNU General Public License as published by
17
16
 
18
17
"""An adapter between a Git Branch and a Bazaar Branch"""
19
18
 
20
 
from dulwich.objects import (
21
 
    Commit,
22
 
    Tag,
23
 
    )
24
 
 
25
19
from bzrlib import (
26
20
    branch,
27
 
    bzrdir,
28
21
    config,
29
 
    errors,
30
 
    foreign,
31
 
    repository,
32
22
    revision,
33
23
    tag,
34
 
    transport,
35
 
    )
36
 
from bzrlib.decorators import (
37
 
    needs_read_lock,
38
 
    )
39
 
from bzrlib.trace import (
40
 
    is_quiet,
41
 
    mutter,
42
 
    )
43
 
 
44
 
from bzrlib.plugins.git import (
45
 
    get_rich_root_format,
46
 
    )
47
 
from bzrlib.plugins.git.config import (
48
 
    GitBranchConfig,
49
 
    )
50
 
from bzrlib.plugins.git.errors import (
51
 
    NoPushSupport,
52
 
    NoSuchRef,
53
 
    )
54
 
 
55
 
try:
56
 
    from bzrlib.foreign import ForeignBranch
57
 
except ImportError:
58
 
    class ForeignBranch(branch.Branch):
59
 
        def __init__(self, mapping):
60
 
            self.mapping = mapping
61
 
            super(ForeignBranch, self).__init__()
62
 
 
63
 
 
64
 
def extract_tags(refs, mapping):
65
 
    ret = {}
66
 
    for k,v in refs.iteritems():
67
 
        if k.startswith("refs/tags/") and not k.endswith("^{}"):
68
 
            v = refs.get(k+"^{}", v)
69
 
            ret[k[len("refs/tags/"):]] = mapping.revision_id_foreign_to_bzr(v)
70
 
    return ret
71
 
 
72
 
 
73
 
class GitPullResult(branch.PullResult):
74
 
 
75
 
    def _lookup_revno(self, revid):
76
 
        assert isinstance(revid, str), "was %r" % revid
77
 
        # Try in source branch first, it'll be faster
78
 
        return self.target_branch.revision_id_to_revno(revid)
79
 
 
80
 
    @property
81
 
    def old_revno(self):
82
 
        return self._lookup_revno(self.old_revid)
83
 
 
84
 
    @property
85
 
    def new_revno(self):
86
 
        return self._lookup_revno(self.new_revid)
87
 
 
88
 
 
89
 
class LocalGitTagDict(tag.BasicTags):
90
 
    """Dictionary with tags in a local repository."""
 
24
    )
 
25
from bzrlib.decorators import needs_read_lock
 
26
 
 
27
from bzrlib.plugins.git.foreign import ForeignBranch
 
28
from bzrlib.plugins.git.mapping import default_mapping
 
29
 
 
30
class GitTagDict(tag.BasicTags):
91
31
 
92
32
    def __init__(self, branch):
93
33
        self.branch = branch
95
35
 
96
36
    def get_tag_dict(self):
97
37
        ret = {}
98
 
        for k,v in self.repository._git.refs.as_dict("refs/tags").iteritems():
99
 
            obj = self.repository._git.get_object(v)
100
 
            while isinstance(obj, Tag):
101
 
                v = obj.object[1]
102
 
                obj = self.repository._git.get_object(v)
103
 
            if not isinstance(obj, Commit):
104
 
                mutter("Tag %s points at object %r that is not a commit, "
105
 
                       "ignoring", k, obj)
106
 
                continue
107
 
            ret[k] = self.branch.mapping.revision_id_foreign_to_bzr(v)
 
38
        for tag in self.repository._git.tags:
 
39
            ret[tag.name] = self.branch.mapping.revision_id_foreign_to_bzr(tag.commit.id)
108
40
        return ret
109
41
 
110
42
    def set_tag(self, name, revid):
111
 
        self.repository._git.refs["refs/tags/%s" % name], _ = \
112
 
            self.branch.mapping.revision_id_bzr_to_foreign(revid)
 
43
        raise NotImplementedError(self.set_tag)
 
44
 
 
45
 
 
46
class GitBranchConfig(config.BranchConfig):
 
47
    """BranchConfig that uses locations.conf in place of branch.conf"""
 
48
 
 
49
    def __init__(self, branch):
 
50
        config.BranchConfig.__init__(self, branch)
 
51
        # do not provide a BranchDataConfig
 
52
        self.option_sources = self.option_sources[0], self.option_sources[2]
 
53
 
 
54
    def set_user_option(self, name, value, local=False):
 
55
        """Force local to True"""
 
56
        config.BranchConfig.set_user_option(self, name, value, local=True)
113
57
 
114
58
 
115
59
class GitBranchFormat(branch.BranchFormat):
120
64
    def supports_tags(self):
121
65
        return True
122
66
 
123
 
    def make_tags(self, branch):
124
 
        if getattr(branch.repository, "get_refs", None) is not None:
125
 
            from bzrlib.plugins.git.remote import RemoteGitTagDict
126
 
            return RemoteGitTagDict(branch)
127
 
        else:
128
 
            return LocalGitTagDict(branch)
129
 
 
130
67
 
131
68
class GitBranch(ForeignBranch):
132
69
    """An adapter to git repositories for bzr Branch objects."""
133
70
 
134
 
    def __init__(self, bzrdir, repository, name, lockfiles):
 
71
    def __init__(self, bzrdir, repository, head, base, lockfiles):
135
72
        self.repository = repository
136
 
        self._format = GitBranchFormat()
 
73
        super(GitBranch, self).__init__(default_mapping)
137
74
        self.control_files = lockfiles
138
75
        self.bzrdir = bzrdir
139
 
        super(GitBranch, self).__init__(repository.get_mapping())
140
 
        self.name = name
141
 
        self._head = None
142
 
        self.base = bzrdir.transport.base
143
 
 
144
 
    def _get_nick(self, local=False, possible_master_transports=None):
145
 
        """Find the nick name for this branch.
146
 
 
147
 
        :return: Branch nick
148
 
        """
149
 
        return self.name
150
 
 
151
 
    def _set_nick(self, nick):
152
 
        raise NotImplementedError
153
 
 
154
 
    nick = property(_get_nick, _set_nick)
155
 
 
156
 
    def __repr__(self):
157
 
        return "%s(%r, %r)" % (self.__class__.__name__, self.repository.base, self.name)
158
 
 
159
 
    def generate_revision_history(self, revid, old_revid=None):
160
 
        # FIXME: Check that old_revid is in the ancestry of revid
161
 
        newhead, self.mapping = self.mapping.revision_id_bzr_to_foreign(revid)
162
 
        self._set_head(newhead)
 
76
        self.head = head
 
77
        self.base = base
 
78
        self._format = GitBranchFormat()
163
79
 
164
80
    def lock_write(self):
165
81
        self.control_files.lock_write()
166
82
 
167
 
    def get_stacked_on_url(self):
168
 
        # Git doesn't do stacking (yet...)
169
 
        return None
170
 
 
171
 
    def get_parent(self):
172
 
        """See Branch.get_parent()."""
173
 
        # FIXME: Set "origin" url from .git/config ?
174
 
        return None
175
 
 
176
 
    def set_parent(self, url):
177
 
        # FIXME: Set "origin" url in .git/config ?
178
 
        pass
179
 
 
180
 
    def lock_read(self):
181
 
        self.control_files.lock_read()
182
 
 
183
 
    def is_locked(self):
184
 
        return self.control_files.is_locked()
185
 
 
186
 
    def unlock(self):
187
 
        self.control_files.unlock()
188
 
 
189
 
    def get_physical_lock_status(self):
190
 
        return False
191
 
 
192
83
    @needs_read_lock
193
84
    def last_revision(self):
194
85
        # perhaps should escape this ?
196
87
            return revision.NULL_REVISION
197
88
        return self.mapping.revision_id_foreign_to_bzr(self.head)
198
89
 
199
 
    def _basic_push(self, target, overwrite=False, stop_revision=None):
200
 
        return branch.InterBranch.get(self, target)._basic_push(
201
 
            overwrite, stop_revision)
202
 
 
203
 
 
204
 
class LocalGitBranch(GitBranch):
205
 
    """A local Git branch."""
206
 
 
207
 
    def _get_checkout_format(self):
208
 
        """Return the most suitable metadir for a checkout of this branch.
209
 
        Weaves are used if this branch's repository uses weaves.
210
 
        """
211
 
        format = self.repository.bzrdir.checkout_metadir()
212
 
        format.set_branch_format(self._format)
213
 
        return format
214
 
 
215
 
    def create_checkout(self, to_location, revision_id=None, lightweight=False,
216
 
        accelerator_tree=None, hardlink=False):
217
 
        if lightweight:
218
 
            t = transport.get_transport(to_location)
219
 
            t.ensure_base()
220
 
            format = self._get_checkout_format()
221
 
            checkout = format.initialize_on_transport(t)
222
 
            from_branch = branch.BranchReferenceFormat().initialize(checkout, 
223
 
                self)
224
 
            tree = checkout.create_workingtree(revision_id,
225
 
                from_branch=from_branch, hardlink=hardlink)
226
 
            return tree
227
 
        else:
228
 
            return self._create_heavyweight_checkout(to_location, revision_id,
229
 
            hardlink)
230
 
 
231
 
    def _create_heavyweight_checkout(self, to_location, revision_id=None, 
232
 
                                     hardlink=False):
233
 
        """Create a new heavyweight checkout of this branch.
234
 
 
235
 
        :param to_location: URL of location to create the new checkout in.
236
 
        :param revision_id: Revision that should be the tip of the checkout.
237
 
        :param hardlink: Whether to hardlink
238
 
        :return: WorkingTree object of checkout.
239
 
        """
240
 
        checkout_branch = bzrdir.BzrDir.create_branch_convenience(
241
 
            to_location, force_new_tree=False, format=get_rich_root_format())
242
 
        checkout = checkout_branch.bzrdir
243
 
        checkout_branch.bind(self)
244
 
        # pull up to the specified revision_id to set the initial 
245
 
        # branch tip correctly, and seed it with history.
246
 
        checkout_branch.pull(self, stop_revision=revision_id)
247
 
        return checkout.create_workingtree(revision_id, hardlink=hardlink)
 
90
    def _make_tags(self):
 
91
        return GitTagDict(self)
 
92
 
 
93
    def get_parent(self):
 
94
        """See Branch.get_parent()."""
 
95
        return None
 
96
 
 
97
    def get_stacked_on_url(self):
 
98
        return None
248
99
 
249
100
    def _gen_revision_history(self):
250
101
        if self.head is None:
251
102
            return []
252
 
        ret = list(self.repository.iter_reverse_revision_history(
253
 
            self.last_revision()))
 
103
        skip = 0
 
104
        cms = None
 
105
        ret = []
 
106
        max_count = 1000
 
107
        nextid = self.head
 
108
        while cms != []:
 
109
            cms = self.repository._git.commits(self.head, max_count=max_count, skip=skip)
 
110
            skip += max_count
 
111
            for cm in cms:
 
112
                if cm.id == nextid:
 
113
                    ret.append(self.mapping.revision_id_foreign_to_bzr(cm.id))
 
114
                    if cm.parents == []:
 
115
                        nextid = None
 
116
                    else:
 
117
                        nextid = cm.parents[0].id
254
118
        ret.reverse()
255
119
        return ret
256
120
 
257
 
    def _get_head(self):
258
 
        try:
259
 
            return self.repository._git.ref(self.name)
260
 
        except KeyError:
261
 
            return None
262
 
 
263
 
    def set_last_revision_info(self, revno, revid):
264
 
        self.set_last_revision(revid)
265
 
 
266
 
    def set_last_revision(self, revid):
267
 
        (self.head, self.mapping) = self.mapping.revision_id_bzr_to_foreign(
268
 
                revid)
269
 
 
270
 
    def _set_head(self, value):
271
 
        self._head = value
272
 
        self.repository._git.refs[self.name] = self._head
273
 
        self._clear_cached_state()
274
 
 
275
 
    head = property(_get_head, _set_head)
276
 
 
277
121
    def get_config(self):
278
122
        return GitBranchConfig(self)
279
123
 
 
124
    def lock_read(self):
 
125
        self.control_files.lock_read()
 
126
 
 
127
    def unlock(self):
 
128
        self.control_files.unlock()
 
129
 
 
130
    def get_physical_lock_status(self):
 
131
        return False
 
132
 
280
133
    def get_push_location(self):
281
134
        """See Branch.get_push_location."""
282
135
        push_loc = self.get_config().get_user_option('push_location')
285
138
    def set_push_location(self, location):
286
139
        """See Branch.set_push_location."""
287
140
        self.get_config().set_user_option('push_location', location,
288
 
                                          store=config.STORE_LOCATION)
 
141
                                          local=True)
289
142
 
290
143
    def supports_tags(self):
291
144
        return True
292
145
 
293
 
 
294
 
class GitBranchPullResult(branch.PullResult):
295
 
 
296
 
    def report(self, to_file):
297
 
        if not is_quiet():
298
 
            if self.old_revid == self.new_revid:
299
 
                to_file.write('No revisions to pull.\n')
300
 
            else:
301
 
                to_file.write('Now on revision %d (git sha: %s).\n' % 
302
 
                        (self.new_revno, self.new_git_head))
303
 
        self._show_tag_conficts(to_file)
304
 
 
305
 
 
306
 
class GitBranchPushResult(branch.BranchPushResult):
307
 
 
308
 
    def _lookup_revno(self, revid):
309
 
        assert isinstance(revid, str), "was %r" % revid
310
 
        # Try in source branch first, it'll be faster
311
 
        try:
312
 
            return self.source_branch.revision_id_to_revno(revid)
313
 
        except NoSuchRevision:
314
 
            # FIXME: Check using graph.find_distance_to_null() ?
315
 
            return self.target_branch.revision_id_to_revno(revid)
316
 
 
317
 
    @property
318
 
    def old_revno(self):
319
 
        return self._lookup_revno(self.old_revid)
320
 
 
321
 
    @property
322
 
    def new_revno(self):
323
 
        return self._lookup_revno(self.new_revid)
324
 
 
325
 
 
326
 
class InterFromGitBranch(branch.GenericInterBranch):
327
 
    """InterBranch implementation that pulls from Git into bzr."""
328
 
 
329
 
    @classmethod
330
 
    def is_compatible(self, source, target):
331
 
        return (isinstance(source, GitBranch) and 
332
 
                not isinstance(target, GitBranch))
333
 
 
334
 
    def update_revisions(self, stop_revision=None, overwrite=False,
335
 
        graph=None):
336
 
        """See InterBranch.update_revisions()."""
337
 
        interrepo = repository.InterRepository.get(self.source.repository, 
338
 
            self.target.repository)
339
 
        self._head = None
340
 
        self._last_revid = None
341
 
        def determine_wants(heads):
342
 
            if not self.source.name in heads:
343
 
                raise NoSuchRef(self.source.name, heads.keys())
344
 
            if stop_revision is not None:
345
 
                self._last_revid = stop_revision
346
 
                self._head, mapping = self.source.repository.lookup_git_revid(
347
 
                    stop_revision)
348
 
            else:
349
 
                self._head = heads[self.source.name]
350
 
                self._last_revid = \
351
 
                    self.source.mapping.revision_id_foreign_to_bzr(self._head)
352
 
            if self.target.repository.has_revision(self._last_revid):
353
 
                return []
354
 
            return [self._head]
355
 
        interrepo.fetch_objects(determine_wants, self.source.mapping)
356
 
        if overwrite:
357
 
            prev_last_revid = None
358
 
        else:
359
 
            prev_last_revid = self.target.last_revision()
360
 
        self.target.generate_revision_history(self._last_revid, prev_last_revid)
361
 
 
362
 
    def pull(self, overwrite=False, stop_revision=None,
363
 
             possible_transports=None, _hook_master=None, run_hooks=True,
364
 
             _override_hook_target=None, local=False):
365
 
        """See Branch.pull.
366
 
 
367
 
        :param _hook_master: Private parameter - set the branch to
368
 
            be supplied as the master to pull hooks.
369
 
        :param run_hooks: Private parameter - if false, this branch
370
 
            is being called because it's the master of the primary branch,
371
 
            so it should not run its hooks.
372
 
        :param _override_hook_target: Private parameter - set the branch to be
373
 
            supplied as the target_branch to pull hooks.
374
 
        """
375
 
        # This type of branch can't be bound.
376
 
        if local:
377
 
            raise errors.LocalRequiresBoundBranch()
378
 
        result = GitBranchPullResult()
379
 
        result.source_branch = self.source
380
 
        if _override_hook_target is None:
381
 
            result.target_branch = self.target
382
 
        else:
383
 
            result.target_branch = _override_hook_target
384
 
        self.source.lock_read()
385
 
        try:
386
 
            # We assume that during 'pull' the target repository is closer than
387
 
            # the source one.
388
 
            graph = self.target.repository.get_graph(self.source.repository)
389
 
            result.old_revno, result.old_revid = \
390
 
                self.target.last_revision_info()
391
 
            self.update_revisions(stop_revision, overwrite=overwrite, 
392
 
                graph=graph)
393
 
            result.new_git_head = self._head
394
 
            result.tag_conflicts = self.source.tags.merge_to(self.target.tags,
395
 
                overwrite)
396
 
            result.new_revno, result.new_revid = self.target.last_revision_info()
397
 
            if _hook_master:
398
 
                result.master_branch = _hook_master
399
 
                result.local_branch = result.target_branch
400
 
            else:
401
 
                result.master_branch = result.target_branch
402
 
                result.local_branch = None
403
 
            if run_hooks:
404
 
                for hook in branch.Branch.hooks['post_pull']:
405
 
                    hook(result)
406
 
        finally:
407
 
            self.source.unlock()
408
 
        return result
409
 
 
410
 
    def _basic_push(self, overwrite=False, stop_revision=None):
411
 
        result = branch.BranchPushResult()
412
 
        result.source_branch = self.source
413
 
        result.target_branch = self.target
414
 
        graph = self.target.repository.get_graph(self.source.repository)
415
 
        result.old_revno, result.old_revid = self.target.last_revision_info()
416
 
        self.update_revisions(stop_revision, overwrite=overwrite, 
417
 
            graph=graph)
418
 
        result.new_git_head = self._head
419
 
        result.tag_conflicts = self.source.tags.merge_to(self.target.tags,
420
 
            overwrite)
421
 
        result.new_revno, result.new_revid = self.target.last_revision_info()
422
 
        return result
423
 
 
424
 
 
425
 
class InterGitBranch(branch.GenericInterBranch):
426
 
    """InterBranch implementation that pulls between Git branches."""
427
 
 
428
 
 
429
 
class InterGitLocalRemoteBranch(InterGitBranch):
430
 
    """InterBranch that copies from a local to a remote git branch."""
431
 
 
432
 
    @classmethod
433
 
    def is_compatible(self, source, target):
434
 
        from bzrlib.plugins.git.remote import RemoteGitBranch
435
 
        return (isinstance(source, LocalGitBranch) and 
436
 
                isinstance(target, RemoteGitBranch))
437
 
 
438
 
    def _basic_push(self, overwrite=False, stop_revision=None):
439
 
        result = GitBranchPushResult()
440
 
        result.source_branch = self.source
441
 
        result.target_branch = self.target
442
 
        if stop_revision is None:
443
 
            stop_revision = self.source.last_revision()
444
 
        # FIXME: Check for diverged branches
445
 
        def get_changed_refs(old_refs):
446
 
            result.old_revid = self.target.mapping.revision_id_foreign_to_bzr(old_refs["refs/heads/master"])
447
 
            refs = { "refs/heads/master": self.source.repository.lookup_git_revid(stop_revision)[0] }
448
 
            result.new_revid = stop_revision
449
 
            for name, sha in self.source.repository._git.refs.as_dict("refs/tags").iteritems():
450
 
                refs["refs/tags/%s" % name] = sha
451
 
            return refs
452
 
        self.target.repository.send_pack(get_changed_refs, 
453
 
                self.source.repository._git.object_store.generate_pack_contents)
454
 
        return result
455
 
 
456
 
 
457
 
class InterGitRemoteLocalBranch(InterGitBranch):
458
 
    """InterBranch that copies from a remote to a local git branch."""
459
 
 
460
 
    @classmethod
461
 
    def is_compatible(self, source, target):
462
 
        from bzrlib.plugins.git.remote import RemoteGitBranch
463
 
        return (isinstance(source, RemoteGitBranch) and 
464
 
                isinstance(target, LocalGitBranch))
465
 
 
466
 
    def _basic_push(self, overwrite=False, stop_revision=None):
467
 
        result = branch.BranchPushResult()
468
 
        result.source_branch = self.source
469
 
        result.target_branch = self.target
470
 
        result.old_revid = self.target.last_revision()
471
 
        refs, stop_revision = self.update_refs(stop_revision)
472
 
        self.target.generate_revision_history(stop_revision, result.old_revid)
473
 
        self.update_tags(refs)
474
 
        result.new_revid = self.target.last_revision()
475
 
        return result
476
 
 
477
 
    def update_tags(self, refs):
478
 
        for name, revid in extract_tags(refs, self.target.mapping).iteritems():
479
 
            self.target.tags.set_tag(name, revid)
480
 
 
481
 
    def update_refs(self, stop_revision=None):
482
 
        interrepo = repository.InterRepository.get(self.source.repository, 
483
 
            self.target.repository)
484
 
        if stop_revision is None:
485
 
            refs = interrepo.fetch_refs(branches=["HEAD"])
486
 
            stop_revision = self.target.mapping.revision_id_foreign_to_bzr(refs["HEAD"])
487
 
        else:
488
 
            refs = interrepo.fetch_refs(revision_id=stop_revision)
489
 
        return refs, stop_revision
490
 
 
491
 
    def pull(self, stop_revision=None, overwrite=False, 
492
 
        possible_transports=None, local=False):
493
 
        # This type of branch can't be bound.
494
 
        if local:
495
 
            raise errors.LocalRequiresBoundBranch()
496
 
        result = GitPullResult()
497
 
        result.source_branch = self.source
498
 
        result.target_branch = self.target
499
 
        result.old_revid = self.target.last_revision()
500
 
        refs, stop_revision = self.update_refs(stop_revision)
501
 
        self.target.generate_revision_history(stop_revision, result.old_revid)
502
 
        self.update_tags(refs)
503
 
        result.new_revid = self.target.last_revision()
504
 
        return result
505
 
 
506
 
    
507
 
class InterToGitBranch(branch.InterBranch):
508
 
    """InterBranch implementation that pulls from Git into bzr."""
509
 
 
510
 
    @classmethod
511
 
    def is_compatible(self, source, target):
512
 
        return (not isinstance(source, GitBranch) and 
513
 
                isinstance(target, GitBranch))
514
 
 
515
 
    def push(self, overwrite=True, stop_revision=None, 
516
 
             _override_hook_source_branch=None):
517
 
        raise NoPushSupport()
518
 
 
519
 
    def lossy_push(self, stop_revision=None):
520
 
        result = GitBranchPushResult()
521
 
        result.source_branch = self.source
522
 
        result.target_branch = self.target
523
 
        result.old_revid = self.target.last_revision()
524
 
        if stop_revision is None:
525
 
            stop_revision = self.source.last_revision()
526
 
        # FIXME: Check for diverged branches
527
 
        refs = { "refs/heads/master": stop_revision }
528
 
        for name, revid in self.source.tags.get_tag_dict().iteritems():
529
 
            if self.source.repository.has_revision(revid):
530
 
                refs["refs/tags/%s" % name] = revid
531
 
        revidmap, new_refs = self.target.repository.dfetch_refs(
532
 
            self.source.repository, refs)
533
 
        if revidmap != {}:
534
 
            self.target.generate_revision_history(revidmap[stop_revision])
535
 
            result.new_revid = revidmap[stop_revision]
536
 
        else:
537
 
            result.new_revid = result.old_revid
538
 
        result.revidmap = revidmap
539
 
        return result
540
 
 
541
 
 
542
 
branch.InterBranch.register_optimiser(InterGitRemoteLocalBranch)
543
 
branch.InterBranch.register_optimiser(InterFromGitBranch)
544
 
branch.InterBranch.register_optimiser(InterToGitBranch)
545
 
branch.InterBranch.register_optimiser(InterGitLocalRemoteBranch)
 
146
    def sprout(self, to_bzrdir, revision_id=None):
 
147
        """See Branch.sprout()."""
 
148
        result = to_bzrdir.create_branch()
 
149
        self.copy_content_into(result, revision_id=revision_id)
 
150
        result.set_parent(self.bzrdir.root_transport.base)
 
151
        return result
 
152