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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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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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raise bzrlib.errors.AmbiguousBase((a_closest[0], b_closest[0]))
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192
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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Return root, ancestors map, descendants map
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TODO: Produce graphs with the NULL revision as root, so that we can find
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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
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be possible. But if we are willing to pretend :)... sure.
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revision_source.lock_read()
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return _revision_graph(revision, revision_source)
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revision_source.unlock()
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def _revision_graph(revision, revision_source):
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"""See revision_graph."""
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from bzrlib.tsort import topo_sort
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graph = revision_source.get_revision_graph(revision)
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# mark all no-parent revisions as being NULL_REVISION parentage.
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for node, parents in graph.items():
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if len(parents) == 0:
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graph[node] = [NULL_REVISION]
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# add NULL_REVISION to the graph
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graph[NULL_REVISION] = []
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# pick a root. If there are multiple roots
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# this could pick a random one.
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topo_order = topo_sort(graph.items())
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# map the descendants of the graph.
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# and setup our set based return graph.
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for node in graph.keys():
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descendants[node] = {}
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for node, parents in graph.items():
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for parent in parents:
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descendants[parent][node] = 1
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ancestors[node] = set(parents)
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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]:
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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
215
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def combined_graph(revision_a, revision_b, revision_source):
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"""Produce a combined ancestry graph.
217
263
Return graph root, ancestors map, descendants map, set of common nodes"""
218
root, ancestors, descendants = revision_graph(
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revision_a, revision_source)
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root_b, ancestors_b, descendants_b = revision_graph(
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revision_b, revision_source)
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root, ancestors, descendants = revision_graph(revision_a, revision_source)
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root_b, ancestors_b, descendants_b = revision_graph(revision_b,
222
267
if root != root_b:
223
raise errors.NoCommonRoot(revision_a, revision_b)
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raise bzrlib.errors.NoCommonRoot(revision_a, revision_b)
225
270
for node, node_anc in ancestors_b.iteritems():
226
271
if node in ancestors:
238
283
def common_ancestor(revision_a, revision_b, revision_source,
239
284
pb=DummyProgress()):
240
if None in (revision_a, revision_b):
242
if NULL_REVISION in (revision_a, revision_b):
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# trivial optimisation
245
if revision_a == revision_b:
249
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pb.update('Picking ancestor', 1, 3)
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graph = revision_source.get_revision_graph_with_ghosts(
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[revision_a, revision_b])
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# convert to a NULL_REVISION based graph.
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ancestors = graph.get_ancestors()
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descendants = graph.get_descendants()
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common = set(graph.get_ancestry(revision_a)).intersection(
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set(graph.get_ancestry(revision_b)))
257
descendants[NULL_REVISION] = {}
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ancestors[NULL_REVISION] = []
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for root in graph.roots:
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descendants[NULL_REVISION][root] = 1
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ancestors[root].append(NULL_REVISION)
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for ghost in graph.ghosts:
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# ghosts act as roots for the purpose of finding
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# the longest paths from the root: any ghost *might*
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# be directly attached to the root, so we treat them
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# ghost now descends from NULL
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descendants[NULL_REVISION][ghost] = 1
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# that is it has an ancestor of NULL
270
ancestors[ghost] = [NULL_REVISION]
271
# ghost is common if any of ghosts descendants are common:
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for ghost_descendant in descendants[ghost]:
273
if ghost_descendant in common:
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common.add(NULL_REVISION)
278
except errors.NoCommonRoot:
279
raise errors.NoCommonAncestor(revision_a, revision_b)
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root, ancestors, descendants, common = \
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combined_graph(revision_a, revision_b, revision_source)
290
except bzrlib.errors.NoCommonRoot:
291
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
281
293
pb.update('Picking ancestor', 2, 3)
282
294
distances = node_distances (descendants, ancestors, root)
283
295
pb.update('Picking ancestor', 3, 2)
284
296
farthest = select_farthest(distances, common)
285
297
if farthest is None or farthest == NULL_REVISION:
286
raise errors.NoCommonAncestor(revision_a, revision_b)
298
raise bzrlib.errors.NoCommonAncestor(revision_a, revision_b)
296
308
assert len(args) != 0
297
309
self._revision_sources = args
299
def revision_parents(self, revision_id):
300
for source in self._revision_sources:
302
return source.revision_parents(revision_id)
303
except (errors.WeaveRevisionNotPresent, errors.NoSuchRevision), e:
307
311
def get_revision(self, revision_id):
308
312
for source in self._revision_sources:
310
314
return source.get_revision(revision_id)
311
except errors.NoSuchRevision, e:
315
except bzrlib.errors.NoSuchRevision, e:
315
def get_revision_graph(self, revision_id):
316
# we could probe incrementally until the pending
317
# ghosts list stop growing, but its cheaper for now
318
# to just ask for the complete graph for each repository.
320
for source in self._revision_sources:
321
ghost_graph = source.get_revision_graph_with_ghosts()
322
graphs.append(ghost_graph)
325
if not revision_id in graph.get_ancestors():
327
if absent == len(graphs):
328
raise errors.NoSuchRevision(self._revision_sources[0], revision_id)
332
pending = set([revision_id])
333
def find_parents(node_id):
334
"""find the parents for node_id."""
336
ancestors = graph.get_ancestors()
338
return ancestors[node_id]
341
raise errors.NoSuchRevision(self._revision_sources[0], node_id)
343
# all the graphs should have identical parent lists
344
node_id = pending.pop()
346
result[node_id] = find_parents(node_id)
347
for parent_node in result[node_id]:
348
if not parent_node in result:
349
pending.add(parent_node)
350
except errors.NoSuchRevision:
355
def get_revision_graph_with_ghosts(self, revision_ids):
356
# query all the sources for their entire graphs
357
# and then build a combined graph for just
360
for source in self._revision_sources:
361
ghost_graph = source.get_revision_graph_with_ghosts()
362
graphs.append(ghost_graph.get_ancestors())
363
for revision_id in revision_ids:
366
if not revision_id in graph:
368
if absent == len(graphs):
369
raise errors.NoSuchRevision(self._revision_sources[0],
374
pending = set(revision_ids)
376
def find_parents(node_id):
377
"""find the parents for node_id."""
380
return graph[node_id]
383
raise errors.NoSuchRevision(self._revision_sources[0], node_id)
385
# all the graphs should have identical parent lists
386
node_id = pending.pop()
388
parents = find_parents(node_id)
389
for parent_node in parents:
391
if (parent_node not in pending and
392
parent_node not in done):
394
pending.add(parent_node)
395
result.add_node(node_id, parents)
397
except errors.NoSuchRevision:
399
result.add_ghost(node_id)
404
for source in self._revision_sources:
408
for source in self._revision_sources:
412
@deprecated_function(zero_eight)
413
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
319
def get_intervening_revisions(ancestor_id, rev_id, rev_source,
414
320
revision_history=None):
415
321
"""Find the longest line of descent from maybe_ancestor to revision.
416
322
Revision history is followed where possible.
422
328
root, ancestors, descendants = revision_graph(rev_id, rev_source)
423
329
if len(descendants) == 0:
424
raise errors.NoSuchRevision(rev_source, rev_id)
330
raise NoSuchRevision(rev_source, rev_id)
425
331
if ancestor_id not in descendants:
426
332
rev_source.get_revision(ancestor_id)
427
raise errors.NotAncestor(rev_id, ancestor_id)
333
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
428
334
root_descendants = all_descendants(descendants, ancestor_id)
429
335
root_descendants.add(ancestor_id)
430
336
if rev_id not in root_descendants:
431
raise errors.NotAncestor(rev_id, ancestor_id)
337
raise bzrlib.errors.NotAncestor(rev_id, ancestor_id)
432
338
distances = node_distances(descendants, ancestors, ancestor_id,
433
339
root_descendants=root_descendants)