15
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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):
19
from bzrlib.graph import node_distances, select_farthest, all_descendants
23
class Revision(object):
31
24
"""Single revision on a branch.
33
26
Revisions may know their revision_hash, but only once they've been
34
27
written out. This is not stored because you cannot write the hash
35
28
into the file it describes.
37
TODO: Perhaps make predecessor be a child element, not an attribute?
30
After bzr 0.0.5 revisions are allowed to have multiple parents.
33
List of parent revision_ids
39
43
def __init__(self, **args):
40
self.inventory_id = None
41
self.revision_id = None
47
44
self.__dict__.update(args)
46
self.parent_sha1s = []
50
49
def __repr__(self):
51
50
return "<Revision id %s>" % self.revision_id
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)
52
def __eq__(self, other):
53
if not isinstance(other, Revision):
55
return (self.inventory_id == other.inventory_id
56
and self.inventory_sha1 == other.inventory_sha1
57
and self.revision_id == other.revision_id
58
and self.timestamp == other.timestamp
59
and self.message == other.message
60
and self.timezone == other.timezone
61
and self.committer == other.committer)
63
def __ne__(self, other):
64
return not self.__eq__(other)
70
def validate_revision_id(rid):
71
"""Check rid is syntactically valid for a revision id."""
73
if not REVISION_ID_RE:
75
REVISION_ID_RE = re.compile('[\w.-]+@[\w.-]+--?\d+--?[0-9a-f]+\Z')
77
if not REVISION_ID_RE.match(rid):
78
raise ValueError("malformed revision-id %r" % rid)
81
def is_ancestor(revision_id, candidate_id, branch):
82
"""Return true if candidate_id is an ancestor of revision_id.
84
A false negative will be returned if any intermediate descendent of
85
candidate_id is not present in any of the revision_sources.
87
revisions_source is an object supporting a get_revision operation that
88
behaves like Branch's.
90
return candidate_id in branch.get_ancestry(revision_id)
93
def iter_ancestors(revision_id, revision_source, only_present=False):
94
ancestors = (revision_id,)
96
while len(ancestors) > 0:
98
for ancestor in ancestors:
100
yield ancestor, distance
102
revision = revision_source.get_revision(ancestor)
103
except bzrlib.errors.NoSuchRevision, e:
104
if e.revision == revision_id:
109
yield ancestor, distance
110
new_ancestors.extend(revision.parent_ids)
111
ancestors = new_ancestors
115
def find_present_ancestors(revision_id, revision_source):
116
"""Return the ancestors of a revision present in a branch.
118
It's possible that a branch won't have the complete ancestry of
119
one of its revisions.
123
anc_iter = enumerate(iter_ancestors(revision_id, revision_source,
125
for anc_order, (anc_id, anc_distance) in anc_iter:
126
if not found_ancestors.has_key(anc_id):
127
found_ancestors[anc_id] = (anc_order, anc_distance)
128
return found_ancestors
131
def __get_closest(intersection):
134
for entry in intersection:
135
if entry[0] == intersection[0][0]:
136
matches.append(entry[2])
140
def old_common_ancestor(revision_a, revision_b, revision_source):
141
"""Find the ancestor common to both revisions that is closest to both.
143
from bzrlib.trace import mutter
144
a_ancestors = find_present_ancestors(revision_a, revision_source)
145
b_ancestors = find_present_ancestors(revision_b, revision_source)
148
# a_order is used as a tie-breaker when two equally-good bases are found
149
for revision, (a_order, a_distance) in a_ancestors.iteritems():
150
if b_ancestors.has_key(revision):
151
a_intersection.append((a_distance, a_order, revision))
152
b_intersection.append((b_ancestors[revision][1], a_order, revision))
153
mutter("a intersection: %r" % a_intersection)
154
mutter("b intersection: %r" % b_intersection)
156
a_closest = __get_closest(a_intersection)
157
if len(a_closest) == 0:
159
b_closest = __get_closest(b_intersection)
160
assert len(b_closest) != 0
161
mutter ("a_closest %r" % a_closest)
162
mutter ("b_closest %r" % b_closest)
163
if a_closest[0] in b_closest:
165
elif b_closest[0] in a_closest:
168
raise bzrlib.errors.AmbiguousBase((a_closest[0], b_closest[0]))
171
def revision_graph(revision, revision_source):
172
"""Produce a graph of the ancestry of the specified revision.
173
Return root, ancestors map, descendants map
175
TODO: Produce graphs with the NULL revision as root, so that we can find
176
a common even when trees are not branches don't represent a single line
183
descendants[revision] = {}
184
while len(lines) > 0:
187
if line == NULL_REVISION:
192
rev = revision_source.get_revision(line)
193
parents = list(rev.parent_ids)
194
if len(parents) == 0:
195
parents = [NULL_REVISION]
196
except bzrlib.errors.NoSuchRevision:
200
if parents is not None:
201
for parent in parents:
202
if parent not in ancestors:
203
new_lines.add(parent)
204
if parent not in descendants:
205
descendants[parent] = {}
206
descendants[parent][line] = 1
207
if parents is not None:
208
ancestors[line] = set(parents)
210
assert root not in descendants[root]
211
assert root not in ancestors[root]
212
return root, ancestors, descendants
214
def combined_graph(revision_a, revision_b, revision_source):
215
"""Produce a combined ancestry graph.
216
Return graph root, ancestors map, descendants map, set of common nodes"""
217
root, ancestors, descendants = revision_graph(revision_a, revision_source)
218
root_b, ancestors_b, descendants_b = revision_graph(revision_b,
221
raise bzrlib.errors.NoCommonRoot(revision_a, revision_b)
223
for node, node_anc in ancestors_b.iteritems():
224
if node in ancestors:
227
ancestors[node] = set()
228
ancestors[node].update(node_anc)
229
for node, node_dec in descendants_b.iteritems():
230
if node not in descendants:
231
descendants[node] = {}
232
descendants[node].update(node_dec)
233
return root, ancestors, descendants, common
235
def common_ancestor(revision_a, revision_b, revision_source):
237
root, ancestors, descendants, common = \
238
combined_graph(revision_a, revision_b, revision_source)
239
except bzrlib.errors.NoCommonRoot:
240
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
242
distances = node_distances (descendants, ancestors, root)
243
farthest = select_farthest(distances, common)
244
if farthest is None or farthest == NULL_REVISION:
245
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
248
class MultipleRevisionSources(object):
249
"""Proxy that looks in multiple branches for revisions."""
250
def __init__(self, *args):
251
object.__init__(self)
252
assert len(args) != 0
253
self._revision_sources = args
255
def get_revision(self, revision_id):
256
for source in self._revision_sources:
258
return source.get_revision(revision_id)
259
except bzrlib.errors.NoSuchRevision, e:
263
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
264
revision_history=None):
265
"""Find the longest line of descent from maybe_ancestor to revision.
266
Revision history is followed where possible.
268
If ancestor_id == rev_id, list will be empty.
269
Otherwise, rev_id will be the last entry. ancestor_id will never appear.
270
If ancestor_id is not an ancestor, NotAncestor will be thrown
272
root, ancestors, descendants = revision_graph(rev_id, rev_source)
273
if len(descendants) == 0:
274
raise NoSuchRevision(rev_source, rev_id)
275
if ancestor_id not in descendants:
276
rev_source.get_revision(ancestor_id)
277
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
278
root_descendants = all_descendants(descendants, ancestor_id)
279
root_descendants.add(ancestor_id)
280
if rev_id not in root_descendants:
281
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
282
distances = node_distances(descendants, ancestors, ancestor_id,
283
root_descendants=root_descendants)
285
def best_ancestor(rev_id):
287
for anc_id in ancestors[rev_id]:
289
distance = distances[anc_id]
292
if revision_history is not None and anc_id in revision_history:
294
elif best is None or distance > best[1]:
295
best = (anc_id, distance)
300
while next != ancestor_id:
302
next = best_ancestor(next)
added
removed
bzrlib/revision.py
