15
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19
from bzrlib.graph import node_distances, select_farthest, all_descendants
23
class Revision(object):
20
from xml import XMLMixin
23
from cElementTree import Element, ElementTree, SubElement
25
from elementtree.ElementTree import Element, ElementTree, SubElement
27
from errors import BzrError
30
class Revision(XMLMixin):
24
31
"""Single revision on a branch.
26
33
Revisions may know their revision_hash, but only once they've been
27
34
written out. This is not stored because you cannot write the hash
28
35
into the file it describes.
30
After bzr 0.0.5 revisions are allowed to have multiple parents.
33
List of parent revision_ids
37
TODO: Perhaps make predecessor be a child element, not an attribute?
36
def __init__(self, revision_id, **args):
37
self.revision_id = revision_id
39
def __init__(self, **args):
40
self.inventory_id = None
41
self.revision_id = None
38
47
self.__dict__.update(args)
40
self.parent_sha1s = []
42
50
def __repr__(self):
43
51
return "<Revision id %s>" % self.revision_id
45
def __eq__(self, other):
46
if not isinstance(other, Revision):
48
# FIXME: rbc 20050930 parent_ids are not being compared
50
self.inventory_sha1 == other.inventory_sha1
51
and self.revision_id == other.revision_id
52
and self.timestamp == other.timestamp
53
and self.message == other.message
54
and self.timezone == other.timezone
55
and self.committer == other.committer)
57
def __ne__(self, other):
58
return not self.__eq__(other)
63
def validate_revision_id(rid):
64
"""Check rid is syntactically valid for a revision id."""
66
if not REVISION_ID_RE:
68
REVISION_ID_RE = re.compile('[\w:.-]+@[\w%.-]+--?[\w]+--?[0-9a-f]+\Z')
70
if not REVISION_ID_RE.match(rid):
71
raise ValueError("malformed revision-id %r" % rid)
74
def is_ancestor(revision_id, candidate_id, branch):
75
"""Return true if candidate_id is an ancestor of revision_id.
77
A false negative will be returned if any intermediate descendent of
78
candidate_id is not present in any of the revision_sources.
80
revisions_source is an object supporting a get_revision operation that
81
behaves like Branch's.
83
return candidate_id in branch.get_ancestry(revision_id)
86
def iter_ancestors(revision_id, revision_source, only_present=False):
87
ancestors = (revision_id,)
89
while len(ancestors) > 0:
91
for ancestor in ancestors:
93
yield ancestor, distance
95
revision = revision_source.get_revision(ancestor)
96
except bzrlib.errors.NoSuchRevision, e:
97
if e.revision == revision_id:
102
yield ancestor, distance
103
new_ancestors.extend(revision.parent_ids)
104
ancestors = new_ancestors
108
def find_present_ancestors(revision_id, revision_source):
109
"""Return the ancestors of a revision present in a branch.
111
It's possible that a branch won't have the complete ancestry of
112
one of its revisions.
116
anc_iter = enumerate(iter_ancestors(revision_id, revision_source,
118
for anc_order, (anc_id, anc_distance) in anc_iter:
119
if not found_ancestors.has_key(anc_id):
120
found_ancestors[anc_id] = (anc_order, anc_distance)
121
return found_ancestors
124
def __get_closest(intersection):
127
for entry in intersection:
128
if entry[0] == intersection[0][0]:
129
matches.append(entry[2])
133
def old_common_ancestor(revision_a, revision_b, revision_source):
134
"""Find the ancestor common to both revisions that is closest to both.
136
from bzrlib.trace import mutter
137
a_ancestors = find_present_ancestors(revision_a, revision_source)
138
b_ancestors = find_present_ancestors(revision_b, revision_source)
141
# a_order is used as a tie-breaker when two equally-good bases are found
142
for revision, (a_order, a_distance) in a_ancestors.iteritems():
143
if b_ancestors.has_key(revision):
144
a_intersection.append((a_distance, a_order, revision))
145
b_intersection.append((b_ancestors[revision][1], a_order, revision))
146
mutter("a intersection: %r" % a_intersection)
147
mutter("b intersection: %r" % b_intersection)
149
a_closest = __get_closest(a_intersection)
150
if len(a_closest) == 0:
152
b_closest = __get_closest(b_intersection)
153
assert len(b_closest) != 0
154
mutter ("a_closest %r" % a_closest)
155
mutter ("b_closest %r" % b_closest)
156
if a_closest[0] in b_closest:
158
elif b_closest[0] in a_closest:
161
raise bzrlib.errors.AmbiguousBase((a_closest[0], b_closest[0]))
164
def revision_graph(revision, revision_source):
165
"""Produce a graph of the ancestry of the specified revision.
166
Return root, ancestors map, descendants map
168
TODO: Produce graphs with the NULL revision as root, so that we can find
169
a common even when trees are not branches don't represent a single line
176
descendants[revision] = {}
177
while len(lines) > 0:
180
if line == NULL_REVISION:
185
rev = revision_source.get_revision(line)
186
parents = list(rev.parent_ids)
187
if len(parents) == 0:
188
parents = [NULL_REVISION]
189
except bzrlib.errors.NoSuchRevision:
193
if parents is not None:
194
for parent in parents:
195
if parent not in ancestors:
196
new_lines.add(parent)
197
if parent not in descendants:
198
descendants[parent] = {}
199
descendants[parent][line] = 1
200
if parents is not None:
201
ancestors[line] = set(parents)
203
assert root not in descendants[root]
204
assert root not in ancestors[root]
205
return root, ancestors, descendants
208
def combined_graph(revision_a, revision_b, revision_source):
209
"""Produce a combined ancestry graph.
210
Return graph root, ancestors map, descendants map, set of common nodes"""
211
root, ancestors, descendants = revision_graph(revision_a, revision_source)
212
root_b, ancestors_b, descendants_b = revision_graph(revision_b,
215
raise bzrlib.errors.NoCommonRoot(revision_a, revision_b)
217
for node, node_anc in ancestors_b.iteritems():
218
if node in ancestors:
221
ancestors[node] = set()
222
ancestors[node].update(node_anc)
223
for node, node_dec in descendants_b.iteritems():
224
if node not in descendants:
225
descendants[node] = {}
226
descendants[node].update(node_dec)
227
return root, ancestors, descendants, common
230
def common_ancestor(revision_a, revision_b, revision_source):
232
root, ancestors, descendants, common = \
233
combined_graph(revision_a, revision_b, revision_source)
234
except bzrlib.errors.NoCommonRoot:
235
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
237
distances = node_distances (descendants, ancestors, root)
238
farthest = select_farthest(distances, common)
239
if farthest is None or farthest == NULL_REVISION:
240
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
244
class MultipleRevisionSources(object):
245
"""Proxy that looks in multiple branches for revisions."""
246
def __init__(self, *args):
247
object.__init__(self)
248
assert len(args) != 0
249
self._revision_sources = args
251
def get_revision(self, revision_id):
252
for source in self._revision_sources:
254
return source.get_revision(revision_id)
255
except bzrlib.errors.NoSuchRevision, e:
259
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
260
revision_history=None):
261
"""Find the longest line of descent from maybe_ancestor to revision.
262
Revision history is followed where possible.
264
If ancestor_id == rev_id, list will be empty.
265
Otherwise, rev_id will be the last entry. ancestor_id will never appear.
266
If ancestor_id is not an ancestor, NotAncestor will be thrown
268
root, ancestors, descendants = revision_graph(rev_id, rev_source)
269
if len(descendants) == 0:
270
raise NoSuchRevision(rev_source, rev_id)
271
if ancestor_id not in descendants:
272
rev_source.get_revision(ancestor_id)
273
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
274
root_descendants = all_descendants(descendants, ancestor_id)
275
root_descendants.add(ancestor_id)
276
if rev_id not in root_descendants:
277
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
278
distances = node_distances(descendants, ancestors, ancestor_id,
279
root_descendants=root_descendants)
281
def best_ancestor(rev_id):
283
for anc_id in ancestors[rev_id]:
285
distance = distances[anc_id]
288
if revision_history is not None and anc_id in revision_history:
290
elif best is None or distance > best[1]:
291
best = (anc_id, distance)
296
while next != ancestor_id:
298
next = best_ancestor(next)
55
root = Element('revision',
56
committer = self.committer,
57
timestamp = '%.9f' % self.timestamp,
58
revision_id = self.revision_id,
59
inventory_id = self.inventory_id,
60
timezone = str(self.timezone))
62
root.set('precursor', self.precursor)
65
msg = SubElement(root, 'message')
66
msg.text = self.message
72
def from_element(cls, elt):
73
# <changeset> is deprecated...
74
if elt.tag not in ('revision', 'changeset'):
75
raise BzrError("unexpected tag in revision file: %r" % elt)
77
cs = cls(committer = elt.get('committer'),
78
timestamp = float(elt.get('timestamp')),
79
precursor = elt.get('precursor'),
80
revision_id = elt.get('revision_id'),
81
inventory_id = elt.get('inventory_id'))
83
v = elt.get('timezone')
84
cs.timezone = v and int(v)
86
cs.message = elt.findtext('message') # text of <message>
89
from_element = classmethod(from_element)
added
removed
bzrlib/revision.py
