3
# This program is free software; you can redistribute it and/or modify
4
# it under the terms of the GNU General Public License as published by
5
# the Free Software Foundation; either version 2 of the License, or
6
# (at your option) any later version.
8
# This program is distributed in the hope that it will be useful,
9
# but WITHOUT ANY WARRANTY; without even the implied warranty of
10
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
# GNU General Public License for more details.
13
# You should have received a copy of the GNU General Public License
14
# along with this program; if not, write to the Free Software
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17
# TODO: Some kind of command-line display of revision properties:
18
# perhaps show them in log -v and allow them as options to the commit command.
21
from bzrlib.graph import node_distances, select_farthest, all_descendants
22
from bzrlib.osutils import contains_whitespace
23
from bzrlib.progress import DummyProgress
27
class Revision(object):
28
"""Single revision on a branch.
30
Revisions may know their revision_hash, but only once they've been
31
written out. This is not stored because you cannot write the hash
32
into the file it describes.
34
After bzr 0.0.5 revisions are allowed to have multiple parents.
37
List of parent revision_ids
40
Dictionary of revision properties. These are attached to the
41
revision as extra metadata. The name must be a single
42
word; the value can be an arbitrary string.
45
def __init__(self, revision_id, properties=None, **args):
46
self.revision_id = revision_id
47
self.properties = properties or {}
48
self._check_properties()
50
self.parent_sha1s = []
51
self.__dict__.update(args)
54
return "<Revision id %s>" % self.revision_id
56
def __eq__(self, other):
57
if not isinstance(other, Revision):
59
# FIXME: rbc 20050930 parent_ids are not being compared
61
self.inventory_sha1 == other.inventory_sha1
62
and self.revision_id == other.revision_id
63
and self.timestamp == other.timestamp
64
and self.message == other.message
65
and self.timezone == other.timezone
66
and self.committer == other.committer
67
and self.properties == other.properties)
69
def __ne__(self, other):
70
return not self.__eq__(other)
72
def _check_properties(self):
73
"""Verify that all revision properties are OK.
75
for name, value in self.properties.iteritems():
76
if not isinstance(name, basestring) or contains_whitespace(name):
77
raise ValueError("invalid property name %r" % name)
78
if not isinstance(value, basestring):
79
raise ValueError("invalid property value %r for %r" %
82
def get_history(self, repository):
83
"""Return the canonical line-of-history for this revision.
85
If ghosts are present this may differ in result from a ghost-free
88
current_revision = self
90
while current_revision is not None:
91
reversed_result.append(current_revision.revision_id)
92
if not len (current_revision.parent_ids):
93
reversed_result.append(None)
94
current_revision = None
96
next_revision_id = current_revision.parent_ids[0]
97
current_revision = repository.get_revision(next_revision_id)
98
reversed_result.reverse()
99
return reversed_result
102
def is_ancestor(revision_id, candidate_id, branch):
103
"""Return true if candidate_id is an ancestor of revision_id.
105
A false negative will be returned if any intermediate descendent of
106
candidate_id is not present in any of the revision_sources.
108
revisions_source is an object supporting a get_revision operation that
109
behaves like Branch's.
111
return candidate_id in branch.repository.get_ancestry(revision_id)
114
def iter_ancestors(revision_id, revision_source, only_present=False):
115
ancestors = (revision_id,)
117
while len(ancestors) > 0:
119
for ancestor in ancestors:
121
yield ancestor, distance
123
revision = revision_source.get_revision(ancestor)
124
except bzrlib.errors.NoSuchRevision, e:
125
if e.revision == revision_id:
130
yield ancestor, distance
131
new_ancestors.extend(revision.parent_ids)
132
ancestors = new_ancestors
136
def find_present_ancestors(revision_id, revision_source):
137
"""Return the ancestors of a revision present in a branch.
139
It's possible that a branch won't have the complete ancestry of
140
one of its revisions.
144
anc_iter = enumerate(iter_ancestors(revision_id, revision_source,
146
for anc_order, (anc_id, anc_distance) in anc_iter:
147
if not found_ancestors.has_key(anc_id):
148
found_ancestors[anc_id] = (anc_order, anc_distance)
149
return found_ancestors
152
def __get_closest(intersection):
155
for entry in intersection:
156
if entry[0] == intersection[0][0]:
157
matches.append(entry[2])
161
def old_common_ancestor(revision_a, revision_b, revision_source):
162
"""Find the ancestor common to both revisions that is closest to both.
164
from bzrlib.trace import mutter
165
a_ancestors = find_present_ancestors(revision_a, revision_source)
166
b_ancestors = find_present_ancestors(revision_b, revision_source)
169
# a_order is used as a tie-breaker when two equally-good bases are found
170
for revision, (a_order, a_distance) in a_ancestors.iteritems():
171
if b_ancestors.has_key(revision):
172
a_intersection.append((a_distance, a_order, revision))
173
b_intersection.append((b_ancestors[revision][1], a_order, revision))
174
mutter("a intersection: %r", a_intersection)
175
mutter("b intersection: %r", b_intersection)
177
a_closest = __get_closest(a_intersection)
178
if len(a_closest) == 0:
180
b_closest = __get_closest(b_intersection)
181
assert len(b_closest) != 0
182
mutter ("a_closest %r", a_closest)
183
mutter ("b_closest %r", b_closest)
184
if a_closest[0] in b_closest:
186
elif b_closest[0] in a_closest:
189
raise bzrlib.errors.AmbiguousBase((a_closest[0], b_closest[0]))
192
def revision_graph(revision, revision_source):
193
"""Produce a graph of the ancestry of the specified revision.
194
Return root, ancestors map, descendants map
196
TODO: Produce graphs with the NULL revision as root, so that we can find
197
a common even when trees are not branches don't represent a single line
199
RBC: 20051024: note that when we have two partial histories, this may not
200
be possible. But if we are willing to pretend :)... sure.
206
descendants[revision] = {}
207
while len(lines) > 0:
210
if line == NULL_REVISION:
215
rev = revision_source.get_revision(line)
216
parents = list(rev.parent_ids)
217
if len(parents) == 0:
218
parents = [NULL_REVISION]
219
except bzrlib.errors.NoSuchRevision:
223
if parents is not None:
224
for parent in parents:
225
if parent not in ancestors:
226
new_lines.add(parent)
227
if parent not in descendants:
228
descendants[parent] = {}
229
descendants[parent][line] = 1
230
if parents is not None:
231
ancestors[line] = set(parents)
234
# The history for revision becomes inaccessible without
235
# actually hitting a no-parents revision. This then
236
# makes these asserts below trigger. So, if root is None
237
# determine the actual root by walking the accessible tree
238
# and then stash NULL_REVISION at the end.
240
descendants[root] = {}
241
# for every revision, check we can access at least
242
# one parent, if we cant, add NULL_REVISION and
244
for rev in ancestors:
245
if len(ancestors[rev]) == 0:
246
raise RuntimeError('unreachable code ?!')
248
for parent in ancestors[rev]:
249
if parent in ancestors:
253
descendants[root][rev] = 1
254
ancestors[rev].add(root)
255
ancestors[root] = set()
256
assert root not in descendants[root]
257
assert root not in ancestors[root]
258
return root, ancestors, descendants
261
def combined_graph(revision_a, revision_b, revision_source):
262
"""Produce a combined ancestry graph.
263
Return graph root, ancestors map, descendants map, set of common nodes"""
264
root, ancestors, descendants = revision_graph(revision_a, revision_source)
265
root_b, ancestors_b, descendants_b = revision_graph(revision_b,
268
raise bzrlib.errors.NoCommonRoot(revision_a, revision_b)
270
for node, node_anc in ancestors_b.iteritems():
271
if node in ancestors:
274
ancestors[node] = set()
275
ancestors[node].update(node_anc)
276
for node, node_dec in descendants_b.iteritems():
277
if node not in descendants:
278
descendants[node] = {}
279
descendants[node].update(node_dec)
280
return root, ancestors, descendants, common
283
def common_ancestor(revision_a, revision_b, revision_source,
287
pb.update('Picking ancestor', 1, 3)
288
root, ancestors, descendants, common = \
289
combined_graph(revision_a, revision_b, revision_source)
290
except bzrlib.errors.NoCommonRoot:
291
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
293
pb.update('Picking ancestor', 2, 3)
294
distances = node_distances (descendants, ancestors, root)
295
pb.update('Picking ancestor', 3, 2)
296
farthest = select_farthest(distances, common)
297
if farthest is None or farthest == NULL_REVISION:
298
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
304
class MultipleRevisionSources(object):
305
"""Proxy that looks in multiple branches for revisions."""
306
def __init__(self, *args):
307
object.__init__(self)
308
assert len(args) != 0
309
self._revision_sources = args
311
def get_revision(self, revision_id):
312
for source in self._revision_sources:
314
return source.get_revision(revision_id)
315
except bzrlib.errors.NoSuchRevision, e:
319
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
320
revision_history=None):
321
"""Find the longest line of descent from maybe_ancestor to revision.
322
Revision history is followed where possible.
324
If ancestor_id == rev_id, list will be empty.
325
Otherwise, rev_id will be the last entry. ancestor_id will never appear.
326
If ancestor_id is not an ancestor, NotAncestor will be thrown
328
root, ancestors, descendants = revision_graph(rev_id, rev_source)
329
if len(descendants) == 0:
330
raise NoSuchRevision(rev_source, rev_id)
331
if ancestor_id not in descendants:
332
rev_source.get_revision(ancestor_id)
333
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
334
root_descendants = all_descendants(descendants, ancestor_id)
335
root_descendants.add(ancestor_id)
336
if rev_id not in root_descendants:
337
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
338
distances = node_distances(descendants, ancestors, ancestor_id,
339
root_descendants=root_descendants)
341
def best_ancestor(rev_id):
343
for anc_id in ancestors[rev_id]:
345
distance = distances[anc_id]
348
if revision_history is not None and anc_id in revision_history:
350
elif best is None or distance > best[1]:
351
best = (anc_id, distance)
356
while next != ancestor_id:
358
next = best_ancestor(next)
added
removed
bzrlib/revision.py
