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def is_reserved_id(revision_id):
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"""Determine whether a revision id is reserved
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:return: True if the revision is is reserved, False otherwise
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def old_common_ancestor(revision_a, revision_b, revision_source):
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"""Find the ancestor common to both revisions that is closest to both.
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return isinstance(revision_id, basestring) and revision_id.endswith(':')
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def check_not_reserved_id(revision_id):
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"""Raise ReservedId if the supplied revision_id is reserved"""
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if is_reserved_id(revision_id):
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raise errors.ReservedId(revision_id)
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def ensure_null(revision_id):
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"""Ensure only NULL_REVISION is used to represent the null revision"""
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if revision_id is None:
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symbol_versioning.warn('NULL_REVISION should be used for the null'
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' revision instead of None, as of bzr 0.91.',
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DeprecationWarning, stacklevel=2)
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from bzrlib.trace import mutter
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a_ancestors = find_present_ancestors(revision_a, revision_source)
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b_ancestors = find_present_ancestors(revision_b, revision_source)
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# a_order is used as a tie-breaker when two equally-good bases are found
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for revision, (a_order, a_distance) in a_ancestors.iteritems():
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if b_ancestors.has_key(revision):
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a_intersection.append((a_distance, a_order, revision))
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b_intersection.append((b_ancestors[revision][1], a_order, revision))
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mutter("a intersection: %r", a_intersection)
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mutter("b intersection: %r", b_intersection)
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a_closest = __get_closest(a_intersection)
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if len(a_closest) == 0:
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b_closest = __get_closest(b_intersection)
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assert len(b_closest) != 0
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mutter ("a_closest %r", a_closest)
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mutter ("b_closest %r", b_closest)
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if a_closest[0] in b_closest:
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elif b_closest[0] in a_closest:
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def is_null(revision_id):
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if revision_id is None:
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symbol_versioning.warn('NULL_REVISION should be used for the null'
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' revision instead of None, as of bzr 0.90.',
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DeprecationWarning, stacklevel=2)
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return revision_id in (None, NULL_REVISION)
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raise bzrlib.errors.AmbiguousBase((a_closest[0], b_closest[0]))
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def revision_graph(revision, revision_source):
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"""Produce a graph of the ancestry of the specified revision.
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Return root, ancestors map, descendants map
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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
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RBC: 20051024: note that when we have two partial histories, this may not
200
be possible. But if we are willing to pretend :)... sure.
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descendants[revision] = {}
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while len(lines) > 0:
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if line == NULL_REVISION:
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rev = revision_source.get_revision(line)
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parents = list(rev.parent_ids)
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if len(parents) == 0:
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parents = [NULL_REVISION]
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except bzrlib.errors.NoSuchRevision:
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if parents is not None:
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for parent in parents:
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if parent not in ancestors:
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new_lines.add(parent)
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if parent not in descendants:
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descendants[parent] = {}
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descendants[parent][line] = 1
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if parents is not None:
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ancestors[line] = set(parents)
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# The history for revision becomes inaccessible without
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# actually hitting a no-parents revision. This then
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# makes these asserts below trigger. So, if root is None
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# determine the actual root by walking the accessible tree
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# and then stash NULL_REVISION at the end.
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descendants[root] = {}
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# for every revision, check we can access at least
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# one parent, if we cant, add NULL_REVISION and
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for rev in ancestors:
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if len(ancestors[rev]) == 0:
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raise RuntimeError('unreachable code ?!')
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for parent in ancestors[rev]:
249
if parent in ancestors:
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descendants[root][rev] = 1
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ancestors[rev].add(root)
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ancestors[root] = set()
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assert root not in descendants[root]
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assert root not in ancestors[root]
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return root, ancestors, descendants
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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)
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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)