match: express anypats(), not prefix(), in terms of the others
When I added prefix() in 9789b4a7c595 (match: introduce boolean
prefix() method, 2014-10-28), we already had always(), isexact(), and
anypats(), so it made sense to write it in terms of them (a prefix
matcher is one that isn't any of the other types). It's only now that
I realize that it's much more natural to define prefix() explicitly
(it's one that uses path: patterns, roughly speaking) and let
anypats() be defined in terms of the others. Remember that these
methods are all used for determining which fast paths are
possible. anypats() simply means that no fast paths are possible (it
could be called complex() instead). Further evidence is that
rootfilesin:some/dir does not have any patterns, but it's still
considered to be an anypats() matcher. That's because anypats() really
just means that it's not a prefix() matcher (and not always() and not
isexact()).
This patch thus changes prefix() to return False by default and
anypats() to return True only if the other three are False. Having
anypats() be True by default also seems like a good thing, because it
means forgetting to override it will lead only to performance bugs,
not correctness bugs.
Since the base class's implementation changes, we're also forced to
update the subclasses. That change exposed and fixed a bug in the
differencematcher: for example when both its two input matchers were
prefix matchers, we would say that the result was also a prefix
matcher, which is incorrect, because e.g "path:dir - path:dir/foo" no
longer matches everything under "dir" (which is what prefix() means).
# changelog bisection for mercurial
#
# Copyright 2007 Matt Mackall
# Copyright 2005, 2006 Benoit Boissinot <benoit.boissinot@ens-lyon.org>
#
# Inspired by git bisect, extension skeleton taken from mq.py.
#
# 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 collections
from .i18n import _
from .node import (
hex,
short,
)
from . import (
error,
)
def bisect(changelog, state):
"""find the next node (if any) for testing during a bisect search.
returns a (nodes, number, good) tuple.
'nodes' is the final result of the bisect if 'number' is 0.
Otherwise 'number' indicates the remaining possible candidates for
the search and 'nodes' contains the next bisect target.
'good' is True if bisect is searching for a first good changeset, False
if searching for a first bad one.
"""
clparents = changelog.parentrevs
skip = set([changelog.rev(n) for n in state['skip']])
def buildancestors(bad, good):
# only the earliest bad revision matters
badrev = min([changelog.rev(n) for n in bad])
goodrevs = [changelog.rev(n) for n in good]
goodrev = min(goodrevs)
# build visit array
ancestors = [None] * (len(changelog) + 1) # an extra for [-1]
# set nodes descended from goodrevs
for rev in goodrevs:
ancestors[rev] = []
for rev in changelog.revs(goodrev + 1):
for prev in clparents(rev):
if ancestors[prev] == []:
ancestors[rev] = []
# clear good revs from array
for rev in goodrevs:
ancestors[rev] = None
for rev in changelog.revs(len(changelog), goodrev):
if ancestors[rev] is None:
for prev in clparents(rev):
ancestors[prev] = None
if ancestors[badrev] is None:
return badrev, None
return badrev, ancestors
good = False
badrev, ancestors = buildancestors(state['bad'], state['good'])
if not ancestors: # looking for bad to good transition?
good = True
badrev, ancestors = buildancestors(state['good'], state['bad'])
bad = changelog.node(badrev)
if not ancestors: # now we're confused
if (len(state['bad']) == 1 and len(state['good']) == 1 and
state['bad'] != state['good']):
raise error.Abort(_("starting revisions are not directly related"))
raise error.Abort(_("inconsistent state, %s:%s is good and bad")
% (badrev, short(bad)))
# build children dict
children = {}
visit = collections.deque([badrev])
candidates = []
while visit:
rev = visit.popleft()
if ancestors[rev] == []:
candidates.append(rev)
for prev in clparents(rev):
if prev != -1:
if prev in children:
children[prev].append(rev)
else:
children[prev] = [rev]
visit.append(prev)
candidates.sort()
# have we narrowed it down to one entry?
# or have all other possible candidates besides 'bad' have been skipped?
tot = len(candidates)
unskipped = [c for c in candidates if (c not in skip) and (c != badrev)]
if tot == 1 or not unskipped:
return ([changelog.node(c) for c in candidates], 0, good)
perfect = tot // 2
# find the best node to test
best_rev = None
best_len = -1
poison = set()
for rev in candidates:
if rev in poison:
# poison children
poison.update(children.get(rev, []))
continue
a = ancestors[rev] or [rev]
ancestors[rev] = None
x = len(a) # number of ancestors
y = tot - x # number of non-ancestors
value = min(x, y) # how good is this test?
if value > best_len and rev not in skip:
best_len = value
best_rev = rev
if value == perfect: # found a perfect candidate? quit early
break
if y < perfect and rev not in skip: # all downhill from here?
# poison children
poison.update(children.get(rev, []))
continue
for c in children.get(rev, []):
if ancestors[c]:
ancestors[c] = list(set(ancestors[c] + a))
else:
ancestors[c] = a + [c]
assert best_rev is not None
best_node = changelog.node(best_rev)
return ([best_node], tot, good)
def extendrange(repo, state, nodes, good):
# bisect is incomplete when it ends on a merge node and
# one of the parent was not checked.
parents = repo[nodes[0]].parents()
if len(parents) > 1:
if good:
side = state['bad']
else:
side = state['good']
num = len(set(i.node() for i in parents) & set(side))
if num == 1:
return parents[0].ancestor(parents[1])
return None
def load_state(repo):
state = {'current': [], 'good': [], 'bad': [], 'skip': []}
for l in repo.vfs.tryreadlines("bisect.state"):
kind, node = l[:-1].split()
node = repo.lookup(node)
if kind not in state:
raise error.Abort(_("unknown bisect kind %s") % kind)
state[kind].append(node)
return state
def save_state(repo, state):
f = repo.vfs("bisect.state", "w", atomictemp=True)
with repo.wlock():
for kind in sorted(state):
for node in state[kind]:
f.write("%s %s\n" % (kind, hex(node)))
f.close()
def resetstate(repo):
"""remove any bisect state from the repository"""
if repo.vfs.exists("bisect.state"):
repo.vfs.unlink("bisect.state")
def checkstate(state):
"""check we have both 'good' and 'bad' to define a range
Raise Abort exception otherwise."""
if state['good'] and state['bad']:
return True
if not state['good']:
raise error.Abort(_('cannot bisect (no known good revisions)'))
else:
raise error.Abort(_('cannot bisect (no known bad revisions)'))
def get(repo, status):
"""
Return a list of revision(s) that match the given status:
- ``good``, ``bad``, ``skip``: csets explicitly marked as good/bad/skip
- ``goods``, ``bads`` : csets topologically good/bad
- ``range`` : csets taking part in the bisection
- ``pruned`` : csets that are goods, bads or skipped
- ``untested`` : csets whose fate is yet unknown
- ``ignored`` : csets ignored due to DAG topology
- ``current`` : the cset currently being bisected
"""
state = load_state(repo)
if status in ('good', 'bad', 'skip', 'current'):
return map(repo.changelog.rev, state[status])
else:
# In the following sets, we do *not* call 'bisect()' with more
# than one level of recursion, because that can be very, very
# time consuming. Instead, we always develop the expression as
# much as possible.
# 'range' is all csets that make the bisection:
# - have a good ancestor and a bad descendant, or conversely
# that's because the bisection can go either way
range = '( bisect(bad)::bisect(good) | bisect(good)::bisect(bad) )'
_t = repo.revs('bisect(good)::bisect(bad)')
# The sets of topologically good or bad csets
if len(_t) == 0:
# Goods are topologically after bads
goods = 'bisect(good)::' # Pruned good csets
bads = '::bisect(bad)' # Pruned bad csets
else:
# Goods are topologically before bads
goods = '::bisect(good)' # Pruned good csets
bads = 'bisect(bad)::' # Pruned bad csets
# 'pruned' is all csets whose fate is already known: good, bad, skip
skips = 'bisect(skip)' # Pruned skipped csets
pruned = '( (%s) | (%s) | (%s) )' % (goods, bads, skips)
# 'untested' is all cset that are- in 'range', but not in 'pruned'
untested = '( (%s) - (%s) )' % (range, pruned)
# 'ignored' is all csets that were not used during the bisection
# due to DAG topology, but may however have had an impact.
# E.g., a branch merged between bads and goods, but whose branch-
# point is out-side of the range.
iba = '::bisect(bad) - ::bisect(good)' # Ignored bads' ancestors
iga = '::bisect(good) - ::bisect(bad)' # Ignored goods' ancestors
ignored = '( ( (%s) | (%s) ) - (%s) )' % (iba, iga, range)
if status == 'range':
return repo.revs(range)
elif status == 'pruned':
return repo.revs(pruned)
elif status == 'untested':
return repo.revs(untested)
elif status == 'ignored':
return repo.revs(ignored)
elif status == "goods":
return repo.revs(goods)
elif status == "bads":
return repo.revs(bads)
else:
raise error.ParseError(_('invalid bisect state'))
def label(repo, node):
rev = repo.changelog.rev(node)
# Try explicit sets
if rev in get(repo, 'good'):
# i18n: bisect changeset status
return _('good')
if rev in get(repo, 'bad'):
# i18n: bisect changeset status
return _('bad')
if rev in get(repo, 'skip'):
# i18n: bisect changeset status
return _('skipped')
if rev in get(repo, 'untested') or rev in get(repo, 'current'):
# i18n: bisect changeset status
return _('untested')
if rev in get(repo, 'ignored'):
# i18n: bisect changeset status
return _('ignored')
# Try implicit sets
if rev in get(repo, 'goods'):
# i18n: bisect changeset status
return _('good (implicit)')
if rev in get(repo, 'bads'):
# i18n: bisect changeset status
return _('bad (implicit)')
return None
def shortlabel(label):
if label:
return label[0].upper()
return None
def printresult(ui, repo, state, displayer, nodes, good):
if len(nodes) == 1:
# narrowed it down to a single revision
if good:
ui.write(_("The first good revision is:\n"))
else:
ui.write(_("The first bad revision is:\n"))
displayer.show(repo[nodes[0]])
extendnode = extendrange(repo, state, nodes, good)
if extendnode is not None:
ui.write(_('Not all ancestors of this changeset have been'
' checked.\nUse bisect --extend to continue the '
'bisection from\nthe common ancestor, %s.\n')
% extendnode)
else:
# multiple possible revisions
if good:
ui.write(_("Due to skipped revisions, the first "
"good revision could be any of:\n"))
else:
ui.write(_("Due to skipped revisions, the first "
"bad revision could be any of:\n"))
for n in nodes:
displayer.show(repo[n])
displayer.close()