22
22
"""Weave - storage of related text file versions"""
24
# before intset (r923) 2000 versions in 41.5s
25
# with intset (r926) 2000 versions in 93s !!!
26
# better to just use plain sets.
28
# making _extract build and return a list, rather than being a generator
31
# with python -O, r923 does 2000 versions in 36.87s
33
# with optimizations to avoid mutating lists - 35.75! I guess copying
34
# all the elements every time costs more than the small manipulations.
35
# a surprisingly small change.
37
# r931, which avoids using a generator for extract, does 36.98s
39
# with memoized inclusions, takes 41.49s; not very good
41
# with slots, takes 37.35s; without takes 39.16, a bit surprising
43
# with the delta calculation mixed in with the add method, rather than
44
# separated, takes 36.78s
46
# with delta folded in and mutation of the list, 36.13s
48
# with all this and simplification of add code, 33s
54
# TODO: Perhaps have copy method for Weave instances?
56
25
# XXX: If we do weaves this way, will a merge still behave the same
57
26
# way if it's done in a different order? That's a pretty desirable
75
44
# TODO: Parallel-extract that passes back each line along with a
76
45
# description of which revisions include it. Nice for checking all
46
# shas or calculating stats in parallel.
79
48
# TODO: Using a single _extract routine and then processing the output
80
49
# is probably inefficient. It's simple enough that we can afford to
81
50
# have slight specializations for different ways its used: annotate,
82
51
# basis for add, get, etc.
84
# TODO: Perhaps the API should work only in names to hide the integer
85
# indexes from the user?
53
# TODO: Probably the API should work only in names to hide the integer
54
# indexes from the user.
56
# TODO: Is there any potential performance win by having an add()
57
# variant that is passed a pre-cooked version of the single basis
60
# TODO: Reweave can possibly be made faster by remembering diffs
61
# where the basis and destination are unchanged.
63
# FIXME: Sometimes we will be given a parents list for a revision
64
# that includes some redundant parents (i.e. already a parent of
65
# something in the list.) We should eliminate them. This can
66
# be done fairly efficiently because the sequence numbers constrain
67
# the possible relationships.
90
from cStringIO import StringIO
93
class WeaveError(Exception):
94
"""Exception in processing weave"""
97
class WeaveFormatError(WeaveError):
98
"""Weave invariant violated"""
72
from difflib import SequenceMatcher
74
from bzrlib.trace import mutter
75
from bzrlib.errors import (WeaveError, WeaveFormatError, WeaveParentMismatch,
76
WeaveRevisionNotPresent, WeaveRevisionAlreadyPresent)
77
import bzrlib.errors as errors
78
from bzrlib.tsort import topo_sort
101
81
class Weave(object):
102
82
"""weave - versioned text file storage.
210
206
def __ne__(self, other):
211
207
return not self.__eq__(other)
209
def __contains__(self, name):
210
return self._name_map.has_key(name)
212
def maybe_lookup(self, name_or_index):
213
"""Convert possible symbolic name to index, or pass through indexes."""
214
if isinstance(name_or_index, (int, long)):
217
return self.lookup(name_or_index)
214
220
def lookup(self, name):
221
"""Convert symbolic version name to index."""
216
223
return self._name_map[name]
218
raise WeaveError("name %s not present in weave %s" %
219
(name, self._weave_name))
225
raise WeaveRevisionNotPresent(name, self)
228
return self._names[:]
230
def iter_names(self):
231
"""Yield a list of all names in this weave."""
232
return iter(self._names)
234
def idx_to_name(self, version):
235
return self._names[version]
237
def _check_repeated_add(self, name, parents, text, sha1):
238
"""Check that a duplicated add is OK.
240
If it is, return the (old) index; otherwise raise an exception.
242
idx = self.lookup(name)
243
if sorted(self._parents[idx]) != sorted(parents) \
244
or sha1 != self._sha1s[idx]:
245
raise WeaveRevisionAlreadyPresent(name, self)
222
def add(self, name, parents, text):
248
def add(self, name, parents, text, sha1=None):
223
249
"""Add a single text on top of the weave.
225
251
Returns the index number of the newly added version.
342
371
return new_version
373
def add_identical(self, old_rev_id, new_rev_id, parents):
374
"""Add an identical text to old_rev_id as new_rev_id."""
375
old_lines = self.get(self.lookup(old_rev_id))
376
self.add(new_rev_id, parents, old_lines)
345
378
def inclusions(self, versions):
346
379
"""Return set of all ancestors of given version(s)."""
347
380
i = set(versions)
352
# include all its parents
353
i.update(self._parents[v])
357
raise ValueError("version %d not present in weave" % v)
381
for v in xrange(max(versions), 0, -1):
383
# include all its parents
384
i.update(self._parents[v])
386
## except IndexError:
387
## raise ValueError("version %d not present in weave" % v)
390
def parents(self, version):
391
return self._parents[version]
394
def parent_names(self, version):
395
"""Return version names for parents of a version."""
396
return map(self.idx_to_name, self._parents[self.lookup(version)])
360
399
def minimal_parents(self, version):
501
544
result.append((istack[-1], lineno, l))
505
raise WFE("unclosed insertion blocks at end of weave",
547
raise WeaveFormatError("unclosed insertion blocks "
548
"at end of weave: %s" % istack)
508
raise WFE("unclosed deletion blocks at end of weave",
550
raise WeaveFormatError("unclosed deletion blocks at end of weave: %s"
515
def get_iter(self, version):
555
def get_iter(self, name_or_index):
516
556
"""Yield lines for the specified version."""
517
for origin, lineno, line in self._extract([version]):
557
incls = [self.maybe_lookup(name_or_index)]
562
# We don't have sha1 sums for multiple entries
564
for origin, lineno, line in self._extract(incls):
521
def get_text(self, version):
569
expected_sha1 = self._sha1s[index]
570
measured_sha1 = cur_sha.hexdigest()
571
if measured_sha1 != expected_sha1:
572
raise errors.WeaveInvalidChecksum(
573
'file %s, revision %s, expected: %s, measured %s'
574
% (self._weave_name, self._names[index],
575
expected_sha1, measured_sha1))
578
def get_text(self, name_or_index):
579
return ''.join(self.get_iter(name_or_index))
522
580
assert isinstance(version, int)
524
s.writelines(self.get_iter(version))
528
def get(self, index):
529
return list(self.get_iter(index))
583
def get_lines(self, name_or_index):
584
return list(self.get_iter(name_or_index))
590
def get_sha1(self, name):
591
"""Get the stored sha1 sum for the given revision.
593
:param name: The name of the version to lookup
595
return self._sha1s[self.lookup(name)]
532
597
def mash_iter(self, included):
533
598
"""Return composed version of multiple included versions."""
599
included = map(self.maybe_lookup, included)
534
600
for origin, lineno, text in self._extract(included):
564
629
raise WeaveFormatError("invalid included version %d for index %d"
565
630
% (inclusions[-1], version))
567
# try extracting all versions; this is a bit slow and parallel
568
# extraction could be used
632
# try extracting all versions; parallel extraction is used
569
633
nv = self.numversions()
634
sha1s = [sha.new() for i in range(nv)]
635
texts = [[] for i in range(nv)]
638
# For creating the ancestry, IntSet is much faster (3.7s vs 0.17s)
639
# The problem is that set membership is much more expensive
641
for p in self._parents[i]:
642
new_inc.update(inclusions[p])
644
#assert set(new_inc) == self.inclusions([i]), 'failed %s != %s' % (new_inc, self.inclusions([i]))
645
inclusions.append(new_inc)
647
nlines = len(self._weave)
649
update_text = 'checking weave'
651
short_name = os.path.basename(self._weave_name)
652
update_text = 'checking %s' % (short_name,)
653
update_text = update_text[:25]
655
for lineno, insert, deleteset, line in self._walk():
657
progress_bar.update(update_text, lineno, nlines)
659
for j, j_inc in enumerate(inclusions):
660
# The active inclusion must be an ancestor,
661
# and no ancestors must have deleted this line,
662
# because we don't support resurrection.
663
if (insert in j_inc) and not (deleteset & j_inc):
664
sha1s[j].update(line)
570
666
for version in range(nv):
572
progress_bar.update('checking text', version, nv)
574
for l in self.get_iter(version):
667
hd = sha1s[version].hexdigest()
577
668
expected = self._sha1s[version]
578
669
if hd != expected:
579
raise WeaveError("mismatched sha1 for version %d; "
580
"got %s, expected %s"
581
% (version, hd, expected))
670
raise errors.WeaveInvalidChecksum(
671
"mismatched sha1 for version %s: "
672
"got %s, expected %s"
673
% (self._names[version], hd, expected))
583
675
# TODO: check insertions are properly nested, that there are
584
676
# no lines outside of insertion blocks, that deletions are
585
677
# properly paired, etc.
589
def merge(self, merge_versions):
590
"""Automerge and mark conflicts between versions.
592
This returns a sequence, each entry describing alternatives
593
for a chunk of the file. Each of the alternatives is given as
596
If there is a chunk of the file where there's no diagreement,
597
only one alternative is given.
600
# approach: find the included versions common to all the
602
raise NotImplementedError()
606
679
def _delta(self, included, lines):
607
680
"""Return changes from basis to new revision.
721
798
'killed-both'), \
802
def join(self, other, pb=None, msg=None):
804
"""Integrate versions from other into this weave.
806
The resulting weave contains all the history of both weaves;
807
any version you could retrieve from either self or other can be
808
retrieved from self after this call.
810
It is illegal for the two weaves to contain different values
811
or different parents for any version. See also reweave().
813
:param other: The other weave to pull into this one
814
:param pb: An optional progress bar
815
:param msg: An optional message to display for progress
817
if other.numversions() == 0:
818
return # nothing to update, easy
819
# two loops so that we do not change ourselves before verifying it
821
# work through in index order to make sure we get all dependencies
822
for other_idx, name in enumerate(other._names):
823
self._check_version_consistent(other, other_idx, name)
831
for other_idx, name in enumerate(other._names):
832
# TODO: If all the parents of the other version are already
833
# present then we can avoid some work by just taking the delta
834
# and adjusting the offsets.
835
new_parents = self._imported_parents(other, other_idx)
836
sha1 = other._sha1s[other_idx]
840
if name in self._name_map:
841
idx = self.lookup(name)
842
n1 = set(map(other.idx_to_name, other._parents[other_idx]))
843
n2 = set(map(self.idx_to_name, self._parents[idx]))
844
if sha1 == self._sha1s[idx] and n1 == n2:
848
pb.update(msg, other_idx, len(other._names))
851
lines = other.get_lines(other_idx)
852
self.add(name, new_parents, lines, sha1)
854
mutter("merged = %d, processed = %d, file_id=%s; deltat=%d"%(
855
merged,processed,self._weave_name, time.time( )-time0))
860
def _imported_parents(self, other, other_idx):
861
"""Return list of parents in self corresponding to indexes in other."""
863
for parent_idx in other._parents[other_idx]:
864
parent_name = other._names[parent_idx]
865
if parent_name not in self._names:
866
# should not be possible
867
raise WeaveError("missing parent {%s} of {%s} in %r"
868
% (parent_name, other._name_map[other_idx], self))
869
new_parents.append(self._name_map[parent_name])
872
def _check_version_consistent(self, other, other_idx, name):
873
"""Check if a version in consistent in this and other.
875
To be consistent it must have:
878
* the same direct parents (by name, not index, and disregarding
881
If present & correct return True;
882
if not present in self return False;
883
if inconsistent raise error."""
884
this_idx = self._name_map.get(name, -1)
886
if self._sha1s[this_idx] != other._sha1s[other_idx]:
887
raise WeaveError("inconsistent texts for version {%s} "
888
"when joining weaves"
890
self_parents = self._parents[this_idx]
891
other_parents = other._parents[other_idx]
892
n1 = set([self._names[i] for i in self_parents])
893
n2 = set([other._names[i] for i in other_parents])
895
raise WeaveParentMismatch("inconsistent parents "
896
"for version {%s}: %s vs %s" % (name, n1, n2))
902
def reweave(self, other, pb=None, msg=None):
903
"""Reweave self with other.
905
:param other: The other weave to merge
906
:param pb: An optional progress bar, indicating how far done we are
907
:param msg: An optional message for the progress
909
new_weave = reweave(self, other, pb=pb, msg=msg)
910
for attr in self.__slots__:
911
setattr(self, attr, getattr(new_weave, attr))
914
def reweave(wa, wb, pb=None, msg=None):
915
"""Combine two weaves and return the result.
917
This works even if a revision R has different parents in
918
wa and wb. In the resulting weave all the parents are given.
920
This is done by just building up a new weave, maintaining ordering
921
of the versions in the two inputs. More efficient approaches
922
might be possible but it should only be necessary to do
923
this operation rarely, when a new previously ghost version is
926
:param pb: An optional progress bar, indicating how far done we are
927
:param msg: An optional message for the progress
931
queue_a = range(wa.numversions())
932
queue_b = range(wb.numversions())
933
# first determine combined parents of all versions
934
# map from version name -> all parent names
935
combined_parents = _reweave_parent_graphs(wa, wb)
936
mutter("combined parents: %r", combined_parents)
937
order = topo_sort(combined_parents.iteritems())
938
mutter("order to reweave: %r", order)
943
for idx, name in enumerate(order):
945
pb.update(msg, idx, len(order))
946
if name in wa._name_map:
947
lines = wa.get_lines(name)
948
if name in wb._name_map:
949
lines_b = wb.get_lines(name)
951
mutter('Weaves differ on content. rev_id {%s}', name)
952
mutter('weaves: %s, %s', wa._weave_name, wb._weave_name)
954
lines = list(difflib.unified_diff(lines, lines_b,
955
wa._weave_name, wb._weave_name))
956
mutter('lines:\n%s', ''.join(lines))
957
raise errors.WeaveTextDiffers(name, wa, wb)
959
lines = wb.get_lines(name)
960
wr.add(name, combined_parents[name], lines)
964
def _reweave_parent_graphs(wa, wb):
965
"""Return combined parent ancestry for two weaves.
967
Returned as a list of (version_name, set(parent_names))"""
969
for weave in [wa, wb]:
970
for idx, name in enumerate(weave._names):
971
p = combined.setdefault(name, set())
972
p.update(map(weave.idx_to_name, weave._parents[idx]))
730
976
def weave_toc(w):
added
removed
bzrlib/weave.py
