Mercurial > hg
view mercurial/ancestor.py @ 40424:7caf632e30c3
filecache: unimplement __set__() and __delete__() (API)
Implementing __set__() implies that the descriptor can't be overridden by
obj.__dict__, which means any property access involves slow function call.
"Data descriptors with __set__() and __get__() defined always override
a redefinition in an instance dictionary. In contrast, non-data descriptors
can be overridden by instances."
https://docs.python.org/2.7/reference/datamodel.html#invoking-descriptors
This patch basically backs out 236bb604dc39, "scmutil: update cached copy
when filecached attribute is assigned (issue3263)." The problem described
in issue3263 (which is #3264 in Bugzilla) should no longer happen since
repo._bookmarkcurrent has been moved to repo._bookmarks.active. We still
have a risk of introducing similar bugs, but I think that's the cost we
have to pay.
$ hg perfrevset 'branch(tip)' -R mercurial
(orig) wall 0.139511 comb 0.140000 user 0.140000 sys 0.000000 (best of 66)
(prev) wall 0.114195 comb 0.110000 user 0.110000 sys 0.000000 (best of 81)
(this) wall 0.099038 comb 0.110000 user 0.100000 sys 0.010000 (best of 93)
author | Yuya Nishihara <yuya@tcha.org> |
---|---|
date | Sat, 20 Oct 2018 17:56:00 +0900 |
parents | 72b94f946e90 |
children | 4856c9b8cbaf |
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line source
# ancestor.py - generic DAG ancestor algorithm for mercurial # # Copyright 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import heapq from .node import nullrev from . import ( policy, pycompat, ) parsers = policy.importmod(r'parsers') def commonancestorsheads(pfunc, *nodes): """Returns a set with the heads of all common ancestors of all nodes, heads(::nodes[0] and ::nodes[1] and ...) . pfunc must return a list of parent vertices for a given vertex. """ if not isinstance(nodes, set): nodes = set(nodes) if nullrev in nodes: return set() if len(nodes) <= 1: return nodes allseen = (1 << len(nodes)) - 1 seen = [0] * (max(nodes) + 1) for i, n in enumerate(nodes): seen[n] = 1 << i poison = 1 << (i + 1) gca = set() interesting = len(nodes) nv = len(seen) - 1 while nv >= 0 and interesting: v = nv nv -= 1 if not seen[v]: continue sv = seen[v] if sv < poison: interesting -= 1 if sv == allseen: gca.add(v) sv |= poison if v in nodes: # history is linear return {v} if sv < poison: for p in pfunc(v): sp = seen[p] if p == nullrev: continue if sp == 0: seen[p] = sv interesting += 1 elif sp != sv: seen[p] |= sv else: for p in pfunc(v): if p == nullrev: continue sp = seen[p] if sp and sp < poison: interesting -= 1 seen[p] = sv return gca def ancestors(pfunc, *orignodes): """ Returns the common ancestors of a and b that are furthest from a root (as measured by longest path). pfunc must return a list of parent vertices for a given vertex. """ def deepest(nodes): interesting = {} count = max(nodes) + 1 depth = [0] * count seen = [0] * count mapping = [] for (i, n) in enumerate(sorted(nodes)): depth[n] = 1 b = 1 << i seen[n] = b interesting[b] = 1 mapping.append((b, n)) nv = count - 1 while nv >= 0 and len(interesting) > 1: v = nv nv -= 1 dv = depth[v] if dv == 0: continue sv = seen[v] for p in pfunc(v): if p == nullrev: continue dp = depth[p] nsp = sp = seen[p] if dp <= dv: depth[p] = dv + 1 if sp != sv: interesting[sv] += 1 nsp = seen[p] = sv if sp: interesting[sp] -= 1 if interesting[sp] == 0: del interesting[sp] elif dv == dp - 1: nsp = sp | sv if nsp == sp: continue seen[p] = nsp interesting.setdefault(nsp, 0) interesting[nsp] += 1 interesting[sp] -= 1 if interesting[sp] == 0: del interesting[sp] interesting[sv] -= 1 if interesting[sv] == 0: del interesting[sv] if len(interesting) != 1: return [] k = 0 for i in interesting: k |= i return set(n for (i, n) in mapping if k & i) gca = commonancestorsheads(pfunc, *orignodes) if len(gca) <= 1: return gca return deepest(gca) class incrementalmissingancestors(object): '''persistent state used to calculate missing ancestors incrementally Although similar in spirit to lazyancestors below, this is a separate class because trying to support contains and missingancestors operations with the same internal data structures adds needless complexity.''' def __init__(self, pfunc, bases): self.bases = set(bases) if not self.bases: self.bases.add(nullrev) self.pfunc = pfunc def hasbases(self): '''whether the common set has any non-trivial bases''' return self.bases and self.bases != {nullrev} def addbases(self, newbases): '''grow the ancestor set by adding new bases''' self.bases.update(newbases) def removeancestorsfrom(self, revs): '''remove all ancestors of bases from the set revs (in place)''' bases = self.bases pfunc = self.pfunc revs.difference_update(bases) # nullrev is always an ancestor revs.discard(nullrev) if not revs: return # anything in revs > start is definitely not an ancestor of bases # revs <= start needs to be investigated start = max(bases) keepcount = sum(1 for r in revs if r > start) if len(revs) == keepcount: # no revs to consider return for curr in pycompat.xrange(start, min(revs) - 1, -1): if curr not in bases: continue revs.discard(curr) bases.update(pfunc(curr)) if len(revs) == keepcount: # no more potential revs to discard break def missingancestors(self, revs): '''return all the ancestors of revs that are not ancestors of self.bases This may include elements from revs. Equivalent to the revset (::revs - ::self.bases). Revs are returned in revision number order, which is a topological order.''' revsvisit = set(revs) basesvisit = self.bases pfunc = self.pfunc bothvisit = revsvisit.intersection(basesvisit) revsvisit.difference_update(bothvisit) if not revsvisit: return [] start = max(max(revsvisit), max(basesvisit)) # At this point, we hold the invariants that: # - revsvisit is the set of nodes we know are an ancestor of at least # one of the nodes in revs # - basesvisit is the same for bases # - bothvisit is the set of nodes we know are ancestors of at least one # of the nodes in revs and one of the nodes in bases. bothvisit and # revsvisit are mutually exclusive, but bothvisit is a subset of # basesvisit. # Now we walk down in reverse topo order, adding parents of nodes # already visited to the sets while maintaining the invariants. When a # node is found in both revsvisit and basesvisit, it is removed from # revsvisit and added to bothvisit. When revsvisit becomes empty, there # are no more ancestors of revs that aren't also ancestors of bases, so # exit. missing = [] for curr in pycompat.xrange(start, nullrev, -1): if not revsvisit: break if curr in bothvisit: bothvisit.remove(curr) # curr's parents might have made it into revsvisit through # another path for p in pfunc(curr): revsvisit.discard(p) basesvisit.add(p) bothvisit.add(p) continue if curr in revsvisit: missing.append(curr) revsvisit.remove(curr) thisvisit = revsvisit othervisit = basesvisit elif curr in basesvisit: thisvisit = basesvisit othervisit = revsvisit else: # not an ancestor of revs or bases: ignore continue for p in pfunc(curr): if p == nullrev: pass elif p in othervisit or p in bothvisit: # p is implicitly in thisvisit. This means p is or should be # in bothvisit revsvisit.discard(p) basesvisit.add(p) bothvisit.add(p) else: # visit later thisvisit.add(p) missing.reverse() return missing # Extracted from lazyancestors.__iter__ to avoid a reference cycle def _lazyancestorsiter(parentrevs, initrevs, stoprev, inclusive): seen = {nullrev} heappush = heapq.heappush heappop = heapq.heappop heapreplace = heapq.heapreplace see = seen.add if inclusive: visit = [-r for r in initrevs] seen.update(initrevs) heapq.heapify(visit) else: visit = [] heapq.heapify(visit) for r in initrevs: p1, p2 = parentrevs(r) if p1 not in seen: heappush(visit, -p1) see(p1) if p2 not in seen: heappush(visit, -p2) see(p2) while visit: current = -visit[0] if current < stoprev: break yield current # optimize out heapq operation if p1 is known to be the next highest # revision, which is quite common in linear history. p1, p2 = parentrevs(current) if p1 not in seen: if current - p1 == 1: visit[0] = -p1 else: heapreplace(visit, -p1) see(p1) else: heappop(visit) if p2 not in seen: heappush(visit, -p2) see(p2) class lazyancestors(object): def __init__(self, pfunc, revs, stoprev=0, inclusive=False): """Create a new object generating ancestors for the given revs. Does not generate revs lower than stoprev. This is computed lazily starting from revs. The object supports iteration and membership. cl should be a changelog and revs should be an iterable. inclusive is a boolean that indicates whether revs should be included. Revs lower than stoprev will not be generated. Result does not include the null revision.""" self._parentrevs = pfunc self._initrevs = revs = [r for r in revs if r >= stoprev] self._stoprev = stoprev self._inclusive = inclusive self._containsseen = set() self._containsiter = _lazyancestorsiter(self._parentrevs, self._initrevs, self._stoprev, self._inclusive) def __nonzero__(self): """False if the set is empty, True otherwise.""" try: next(iter(self)) return True except StopIteration: return False __bool__ = __nonzero__ def __iter__(self): """Generate the ancestors of _initrevs in reverse topological order. If inclusive is False, yield a sequence of revision numbers starting with the parents of each revision in revs, i.e., each revision is *not* considered an ancestor of itself. Results are emitted in reverse revision number order. That order is also topological: a child is always emitted before its parent. If inclusive is True, the source revisions are also yielded. The reverse revision number order is still enforced.""" return _lazyancestorsiter(self._parentrevs, self._initrevs, self._stoprev, self._inclusive) def __contains__(self, target): """Test whether target is an ancestor of self._initrevs.""" seen = self._containsseen if target in seen: return True iter = self._containsiter if iter is None: # Iterator exhausted return False # Only integer target is valid, but some callers expect 'None in self' # to be False. So we explicitly allow it. if target is None: return False see = seen.add try: while True: rev = next(iter) see(rev) if rev == target: return True if rev < target: return False except StopIteration: # Set to None to indicate fast-path can be used next time, and to # free up memory. self._containsiter = None return False class rustlazyancestors(object): def __init__(self, index, revs, stoprev=0, inclusive=False): self._index = index self._stoprev = stoprev self._inclusive = inclusive # no need to prefilter out init revs that are smaller than stoprev, # it's done by rustlazyancestors constructor. # we need to convert to a list, because our ruslazyancestors # constructor (from C code) doesn't understand anything else yet self._initrevs = initrevs = list(revs) self._containsiter = parsers.rustlazyancestors( index, initrevs, stoprev, inclusive) def __nonzero__(self): """False if the set is empty, True otherwise. It's better to duplicate this essentially trivial method than to subclass lazyancestors """ try: next(iter(self)) return True except StopIteration: return False def __iter__(self): return parsers.rustlazyancestors(self._index, self._initrevs, self._stoprev, self._inclusive) def __contains__(self, target): return target in self._containsiter