##// END OF EJS Templates
strip: make query to get new bookmark target cheaper...
strip: make query to get new bookmark target cheaper The current query to get the new bookmark target for stripped revisions involves multiple walks up the DAG, and is really expensive, taking over 2.5 seconds on a repository with over 400,000 changesets even if just one changeset is being stripped. A slightly simplified version of the current query is max(heads(::<tostrip> - <tostrip>)) We make two observations here. 1. For any set s, max(heads(s)) == max(s). That is because revision numbers define a topological order, so that the element with the highest revision number in s will not have any children in s. 2. For any set s, max(::s - s) == max(parents(s) - s). In other words, the ancestor of s with the highest revision number not in s is a parent of one of the revs in s. Why? Because if it were an ancestor but not a parent of s, it would have a descendant that would be a parent of s. This descendant would have a higher revision number, leading to a contradiction. Combining these two observations, we rewrite the revset query as max(parents(<tostrip>) - <tostrip>) The time complexity is now linear in the number of changesets being stripped. For the above repository, the query now takes 0.1 seconds when one changeset is stripped. This speeds up operations that use repair.strip, like the rebase and strip commands.

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config.py
183 lines | 6.3 KiB | text/x-python | PythonLexer
# config.py - configuration parsing for Mercurial
#
# Copyright 2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from i18n import _
import error, util
import os, errno
class sortdict(dict):
'a simple sorted dictionary'
def __init__(self, data=None):
self._list = []
if data:
self.update(data)
def copy(self):
return sortdict(self)
def __setitem__(self, key, val):
if key in self:
self._list.remove(key)
self._list.append(key)
dict.__setitem__(self, key, val)
def __iter__(self):
return self._list.__iter__()
def update(self, src):
for k in src:
self[k] = src[k]
def clear(self):
dict.clear(self)
self._list = []
def items(self):
return [(k, self[k]) for k in self._list]
def __delitem__(self, key):
dict.__delitem__(self, key)
self._list.remove(key)
def keys(self):
return self._list
def iterkeys(self):
return self._list.__iter__()
class config(object):
def __init__(self, data=None):
self._data = {}
self._source = {}
if data:
for k in data._data:
self._data[k] = data[k].copy()
self._source = data._source.copy()
def copy(self):
return config(self)
def __contains__(self, section):
return section in self._data
def __getitem__(self, section):
return self._data.get(section, {})
def __iter__(self):
for d in self.sections():
yield d
def update(self, src):
for s in src:
if s not in self:
self._data[s] = sortdict()
self._data[s].update(src._data[s])
self._source.update(src._source)
def get(self, section, item, default=None):
return self._data.get(section, {}).get(item, default)
def backup(self, section, item):
"""return a tuple allowing restore to reinstall a previous value
The main reason we need it is because it handles the "no data" case.
"""
try:
value = self._data[section][item]
source = self.source(section, item)
return (section, item, value, source)
except KeyError:
return (section, item)
def source(self, section, item):
return self._source.get((section, item), "")
def sections(self):
return sorted(self._data.keys())
def items(self, section):
return self._data.get(section, {}).items()
def set(self, section, item, value, source=""):
if section not in self:
self._data[section] = sortdict()
self._data[section][item] = value
self._source[(section, item)] = source
def restore(self, data):
"""restore data returned by self.backup"""
if len(data) == 4:
# restore old data
section, item, value, source = data
self._data[section][item] = value
self._source[(section, item)] = source
else:
# no data before, remove everything
section, item = data
if section in self._data:
del self._data[section][item]
self._source.pop((section, item), None)
def parse(self, src, data, sections=None, remap=None, include=None):
sectionre = util.compilere(r'\[([^\[]+)\]')
itemre = util.compilere(r'([^=\s][^=]*?)\s*=\s*(.*\S|)')
contre = util.compilere(r'\s+(\S|\S.*\S)\s*$')
emptyre = util.compilere(r'(;|#|\s*$)')
commentre = util.compilere(r'(;|#)')
unsetre = util.compilere(r'%unset\s+(\S+)')
includere = util.compilere(r'%include\s+(\S|\S.*\S)\s*$')
section = ""
item = None
line = 0
cont = False
for l in data.splitlines(True):
line += 1
if line == 1 and l.startswith('\xef\xbb\xbf'):
# Someone set us up the BOM
l = l[3:]
if cont:
if commentre.match(l):
continue
m = contre.match(l)
if m:
if sections and section not in sections:
continue
v = self.get(section, item) + "\n" + m.group(1)
self.set(section, item, v, "%s:%d" % (src, line))
continue
item = None
cont = False
m = includere.match(l)
if m:
inc = util.expandpath(m.group(1))
base = os.path.dirname(src)
inc = os.path.normpath(os.path.join(base, inc))
if include:
try:
include(inc, remap=remap, sections=sections)
except IOError, inst:
if inst.errno != errno.ENOENT:
raise error.ParseError(_("cannot include %s (%s)")
% (inc, inst.strerror),
"%s:%s" % (src, line))
continue
if emptyre.match(l):
continue
m = sectionre.match(l)
if m:
section = m.group(1)
if remap:
section = remap.get(section, section)
if section not in self:
self._data[section] = sortdict()
continue
m = itemre.match(l)
if m:
item = m.group(1)
cont = True
if sections and section not in sections:
continue
self.set(section, item, m.group(2), "%s:%d" % (src, line))
continue
m = unsetre.match(l)
if m:
name = m.group(1)
if sections and section not in sections:
continue
if self.get(section, name) is not None:
del self._data[section][name]
continue
raise error.ParseError(l.rstrip(), ("%s:%s" % (src, line)))
def read(self, path, fp=None, sections=None, remap=None):
if not fp:
fp = util.posixfile(path)
self.parse(path, fp.read(), sections, remap, self.read)