convert: optimize convert of files that are unmodified from p2 in merges
Conversion of a merge starts with p1 and re-adds the files that were changed in
the merge or came unmodified from p2. Files that are unmodified from p1 will
thus not be touched and take no time. Files that are unmodified from p2 would be
retrieved and rehashed. They would end up getting the same hash as in p2 and end
up reusing the filelog entry and look like the p1 case ... but it was slow.
Instead, make getchanges also return 'files that are unmodified from p2' so the
sink can reuse the existing p2 entry instead of calling getfile.
Reuse of filelog entries can make a big difference when files are big and with
long revlong chains so they take time to retrieve and hash, or when using an
expensive custom getfile function (think
http://mercurial.selenic.com/wiki/ConvertExtension#Customization with a code
reformatter).
This in combination with changes to reuse filectx entries in
localrepo._filecommit make 'unchanged from p2' almost as fast as 'unchanged
from p1'.
This is so far only implemented for the combination of hg source and hg sink.
This is a refactoring/optimization. It is covered by existing tests and show no
changes - which is a good thing.
# darcs.py - darcs support for the convert extension
#
# Copyright 2007-2009 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 common import NoRepo, checktool, commandline, commit, converter_source
from mercurial.i18n import _
from mercurial import util
import os, shutil, tempfile, re, errno
# The naming drift of ElementTree is fun!
try:
from xml.etree.cElementTree import ElementTree, XMLParser
except ImportError:
try:
from xml.etree.ElementTree import ElementTree, XMLParser
except ImportError:
try:
from elementtree.cElementTree import ElementTree, XMLParser
except ImportError:
try:
from elementtree.ElementTree import ElementTree, XMLParser
except ImportError:
pass
class darcs_source(converter_source, commandline):
def __init__(self, ui, path, rev=None):
converter_source.__init__(self, ui, path, rev=rev)
commandline.__init__(self, ui, 'darcs')
# check for _darcs, ElementTree so that we can easily skip
# test-convert-darcs if ElementTree is not around
if not os.path.exists(os.path.join(path, '_darcs')):
raise NoRepo(_("%s does not look like a darcs repository") % path)
checktool('darcs')
version = self.run0('--version').splitlines()[0].strip()
if version < '2.1':
raise util.Abort(_('darcs version 2.1 or newer needed (found %r)') %
version)
if "ElementTree" not in globals():
raise util.Abort(_("Python ElementTree module is not available"))
self.path = os.path.realpath(path)
self.lastrev = None
self.changes = {}
self.parents = {}
self.tags = {}
# Check darcs repository format
format = self.format()
if format:
if format in ('darcs-1.0', 'hashed'):
raise NoRepo(_("%s repository format is unsupported, "
"please upgrade") % format)
else:
self.ui.warn(_('failed to detect repository format!'))
def before(self):
self.tmppath = tempfile.mkdtemp(
prefix='convert-' + os.path.basename(self.path) + '-')
output, status = self.run('init', repodir=self.tmppath)
self.checkexit(status)
tree = self.xml('changes', xml_output=True, summary=True,
repodir=self.path)
tagname = None
child = None
for elt in tree.findall('patch'):
node = elt.get('hash')
name = elt.findtext('name', '')
if name.startswith('TAG '):
tagname = name[4:].strip()
elif tagname is not None:
self.tags[tagname] = node
tagname = None
self.changes[node] = elt
self.parents[child] = [node]
child = node
self.parents[child] = []
def after(self):
self.ui.debug('cleaning up %s\n' % self.tmppath)
shutil.rmtree(self.tmppath, ignore_errors=True)
def recode(self, s, encoding=None):
if isinstance(s, unicode):
# XMLParser returns unicode objects for anything it can't
# encode into ASCII. We convert them back to str to get
# recode's normal conversion behavior.
s = s.encode('latin-1')
return super(darcs_source, self).recode(s, encoding)
def xml(self, cmd, **kwargs):
# NOTE: darcs is currently encoding agnostic and will print
# patch metadata byte-for-byte, even in the XML changelog.
etree = ElementTree()
# While we are decoding the XML as latin-1 to be as liberal as
# possible, etree will still raise an exception if any
# non-printable characters are in the XML changelog.
parser = XMLParser(encoding='latin-1')
p = self._run(cmd, **kwargs)
etree.parse(p.stdout, parser=parser)
p.wait()
self.checkexit(p.returncode)
return etree.getroot()
def format(self):
output, status = self.run('show', 'repo', no_files=True,
repodir=self.path)
self.checkexit(status)
m = re.search(r'^\s*Format:\s*(.*)$', output, re.MULTILINE)
if not m:
return None
return ','.join(sorted(f.strip() for f in m.group(1).split(',')))
def manifest(self):
man = []
output, status = self.run('show', 'files', no_directories=True,
repodir=self.tmppath)
self.checkexit(status)
for line in output.split('\n'):
path = line[2:]
if path:
man.append(path)
return man
def getheads(self):
return self.parents[None]
def getcommit(self, rev):
elt = self.changes[rev]
date = util.strdate(elt.get('local_date'), '%a %b %d %H:%M:%S %Z %Y')
desc = elt.findtext('name') + '\n' + elt.findtext('comment', '')
# etree can return unicode objects for name, comment, and author,
# so recode() is used to ensure str objects are emitted.
return commit(author=self.recode(elt.get('author')),
date=util.datestr(date, '%Y-%m-%d %H:%M:%S %1%2'),
desc=self.recode(desc).strip(),
parents=self.parents[rev])
def pull(self, rev):
output, status = self.run('pull', self.path, all=True,
match='hash %s' % rev,
no_test=True, no_posthook=True,
external_merge='/bin/false',
repodir=self.tmppath)
if status:
if output.find('We have conflicts in') == -1:
self.checkexit(status, output)
output, status = self.run('revert', all=True, repodir=self.tmppath)
self.checkexit(status, output)
def getchanges(self, rev, full):
if full:
raise util.Abort(_("convert from darcs do not support --full"))
copies = {}
changes = []
man = None
for elt in self.changes[rev].find('summary').getchildren():
if elt.tag in ('add_directory', 'remove_directory'):
continue
if elt.tag == 'move':
if man is None:
man = self.manifest()
source, dest = elt.get('from'), elt.get('to')
if source in man:
# File move
changes.append((source, rev))
changes.append((dest, rev))
copies[dest] = source
else:
# Directory move, deduce file moves from manifest
source = source + '/'
for f in man:
if not f.startswith(source):
continue
fdest = dest + '/' + f[len(source):]
changes.append((f, rev))
changes.append((fdest, rev))
copies[fdest] = f
else:
changes.append((elt.text.strip(), rev))
self.pull(rev)
self.lastrev = rev
return sorted(changes), copies, set()
def getfile(self, name, rev):
if rev != self.lastrev:
raise util.Abort(_('internal calling inconsistency'))
path = os.path.join(self.tmppath, name)
try:
data = util.readfile(path)
mode = os.lstat(path).st_mode
except IOError, inst:
if inst.errno == errno.ENOENT:
return None, None
raise
mode = (mode & 0111) and 'x' or ''
return data, mode
def gettags(self):
return self.tags