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):
21
class RevisionReference(object):
23
Reference to a stored revision.
25
Includes the revision_id and revision_sha1.
29
def __init__(self, revision_id, revision_sha1=None):
30
if revision_id == None \
31
or isinstance(revision_id, basestring):
32
self.revision_id = revision_id
34
raise ValueError('bad revision_id %r' % revision_id)
36
if revision_sha1 != None:
37
if isinstance(revision_sha1, basestring) \
38
and len(revision_sha1) == 40:
39
self.revision_sha1 = revision_sha1
41
raise ValueError('bad revision_sha1 %r' % revision_sha1)
45
class Revision(object):
31
46
"""Single revision on a branch.
33
48
Revisions may know their revision_hash, but only once they've been
34
49
written out. This is not stored because you cannot write the hash
35
50
into the file it describes.
37
TODO: Perhaps make predecessor be a child element, not an attribute?
52
After bzr 0.0.5 revisions are allowed to have multiple parents.
55
List of parent revisions, each is a RevisionReference.
39
65
def __init__(self, **args):
40
self.inventory_id = None
41
self.revision_id = None
47
66
self.__dict__.update(args)
50
70
def __repr__(self):
54
74
def to_element(self):
75
from bzrlib.xml import Element, SubElement
55
77
root = Element('revision',
56
78
committer = self.committer,
57
79
timestamp = '%.9f' % self.timestamp,
58
80
revision_id = self.revision_id,
59
81
inventory_id = self.inventory_id,
60
timezone = str(self.timezone))
62
root.set('precursor', self.precursor)
82
inventory_sha1 = self.inventory_sha1,
85
root.set('timezone', str(self.timezone))
65
88
msg = SubElement(root, 'message')
66
89
msg.text = self.message
93
pelts = SubElement(root, 'parents')
94
pelts.tail = pelts.text = '\n'
95
for rr in self.parents:
96
assert isinstance(rr, RevisionReference)
97
p = SubElement(pelts, 'revision_ref')
100
p.set('revision_id', rr.revision_id)
102
p.set('revision_sha1', rr.revision_sha1)
72
107
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>
108
return unpack_revision(elt)
89
110
from_element = classmethod(from_element)
114
def unpack_revision(elt):
115
"""Convert XML element into Revision object."""
116
# <changeset> is deprecated...
117
if elt.tag not in ('revision', 'changeset'):
118
raise bzrlib.errors.BzrError("unexpected tag in revision file: %r" % elt)
120
rev = Revision(committer = elt.get('committer'),
121
timestamp = float(elt.get('timestamp')),
122
revision_id = elt.get('revision_id'),
123
inventory_id = elt.get('inventory_id'),
124
inventory_sha1 = elt.get('inventory_sha1')
127
precursor = elt.get('precursor')
128
precursor_sha1 = elt.get('precursor_sha1')
130
pelts = elt.find('parents')
134
assert p.tag == 'revision_ref', \
135
"bad parent node tag %r" % p.tag
136
rev_ref = RevisionReference(p.get('revision_id'),
137
p.get('revision_sha1'))
138
rev.parents.append(rev_ref)
142
prec_parent = rev.parents[0].revision_id
143
assert prec_parent == precursor
145
# revisions written prior to 0.0.5 have a single precursor
146
# give as an attribute
147
rev_ref = RevisionReference(precursor, precursor_sha1)
148
rev.parents.append(rev_ref)
150
v = elt.get('timezone')
151
rev.timezone = v and int(v)
153
rev.message = elt.findtext('message') # text of <message>
158
REVISION_ID_RE = None
160
def validate_revision_id(rid):
161
"""Check rid is syntactically valid for a revision id."""
162
global REVISION_ID_RE
163
if not REVISION_ID_RE:
165
REVISION_ID_RE = re.compile('[\w.-]+@[\w.-]+--?\d+--?[0-9a-f]+\Z')
167
if not REVISION_ID_RE.match(rid):
168
raise ValueError("malformed revision-id %r" % rid)
170
def is_ancestor(revision_id, candidate_id, revision_source):
171
"""Return true if candidate_id is an ancestor of revision_id.
172
A false negative will be returned if any intermediate descendent of
173
candidate_id is not present in any of the revision_sources.
175
revisions_source is an object supporting a get_revision operation that
176
behaves like Branch's.
179
for ancestor_id, distance in iter_ancestors(revision_id, revision_source):
180
if ancestor_id == candidate_id:
184
def iter_ancestors(revision_id, revision_source, only_present=False):
185
ancestors = (revision_id,)
187
while len(ancestors) > 0:
189
for ancestor in ancestors:
191
yield ancestor, distance
193
revision = revision_source.get_revision(ancestor)
194
except bzrlib.errors.NoSuchRevision, e:
195
if e.revision == revision_id:
200
yield ancestor, distance
201
new_ancestors.extend([p.revision_id for p in revision.parents])
202
ancestors = new_ancestors
206
def find_present_ancestors(revision_id, revision_source):
209
anc_iter = enumerate(iter_ancestors(revision_id, revision_source,
211
for anc_order, (anc_id, anc_distance) in anc_iter:
212
if not found_ancestors.has_key(anc_id):
213
found_ancestors[anc_id] = (anc_order, anc_distance)
214
return found_ancestors
216
class AmbiguousBase(bzrlib.errors.BzrError):
217
def __init__(self, bases):
218
msg = "The correct base is unclear, becase %s are all equally close" %\
220
bzrlib.errors.BzrError.__init__(self, msg)
223
def common_ancestor(revision_a, revision_b, revision_source):
224
"""Find the ancestor common to both revisions that is closest to both.
226
from bzrlib.trace import mutter
227
a_ancestors = find_present_ancestors(revision_a, revision_source)
228
b_ancestors = find_present_ancestors(revision_b, revision_source)
231
# a_order is used as a tie-breaker when two equally-good bases are found
232
for revision, (a_order, a_distance) in a_ancestors.iteritems():
233
if b_ancestors.has_key(revision):
234
a_intersection.append((a_distance, a_order, revision))
235
b_intersection.append((b_ancestors[revision][1], a_order, revision))
236
mutter("a intersection: %r" % a_intersection)
237
mutter("b intersection: %r" % b_intersection)
238
def get_closest(intersection):
241
for entry in intersection:
242
if entry[0] == intersection[0][0]:
243
matches.append(entry[2])
246
a_closest = get_closest(a_intersection)
247
if len(a_closest) == 0:
249
b_closest = get_closest(b_intersection)
250
assert len(b_closest) != 0
251
mutter ("a_closest %r" % a_closest)
252
mutter ("b_closest %r" % b_closest)
253
if a_closest[0] in b_closest:
255
elif b_closest[0] in a_closest:
258
raise AmbiguousBase((a_closest[0], b_closest[0]))
261
class MultipleRevisionSources(object):
262
def __init__(self, *args):
263
object.__init__(self)
264
assert len(args) != 0
265
self._revision_sources = args
267
def get_revision(self, revision_id):
268
for source in self._revision_sources:
270
return source.get_revision(revision_id)
271
except bzrlib.errors.NoSuchRevision, e:
275
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
276
revision_history=None):
277
"""Find the longest line of descent from maybe_ancestor to revision.
278
Revision history is followed where possible.
280
If ancestor_id == rev_id, list will be empty.
281
Otherwise, rev_id will be the last entry. ancestor_id will never appear.
282
If ancestor_id is not an ancestor, NotAncestor will be thrown
284
[rev_source.get_revision(r) for r in (ancestor_id, rev_id)]
285
if ancestor_id == rev_id:
287
def historical_lines(line):
288
"""Return a tuple of historical/non_historical lines, for sorting.
289
The non_historical count is negative, since non_historical lines are
294
for revision in line:
295
if revision in revision_history:
299
return good_count, bad_count
301
successful_lines = []
302
while len(active) > 0:
305
parent_ids = [p.revision_id for p in
306
rev_source.get_revision(line[-1]).parents]
307
for parent in parent_ids:
309
if parent == ancestor_id:
310
successful_lines.append(line_copy)
312
line_copy.append(parent)
313
new_active.append(line_copy)
315
if len(successful_lines) == 0:
316
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
317
for line in successful_lines:
319
if revision_history is not None:
320
by_historical_lines = []
321
for line in successful_lines:
322
count = historical_lines(line)
323
by_historical_lines.append((count, line))
324
by_historical_lines.sort()
325
if by_historical_lines[-1][0][0] > 0:
326
return by_historical_lines[-1][1]
327
assert len(successful_lines)
328
successful_lines.sort(cmp, len)
329
return successful_lines[-1]