obsolete: extract obsolescence marker pulling into a dedicated function
Having a dedicated function will allow us to experiment with other exchange
strategies in an extension. As we have no solid clues about how to do it right,
being able to experiment is vital.
Some transaction tricks are necessary for pull. But nothing too scary.
# filelog.py - file history class for mercurial
#
# Copyright 2005-2007 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.
import revlog
import re
_mdre = re.compile('\1\n')
def _parsemeta(text):
"""return (metadatadict, keylist, metadatasize)"""
# text can be buffer, so we can't use .startswith or .index
if text[:2] != '\1\n':
return None, None, None
s = _mdre.search(text, 2).start()
mtext = text[2:s]
meta = {}
keys = []
for l in mtext.splitlines():
k, v = l.split(": ", 1)
meta[k] = v
keys.append(k)
return meta, keys, (s + 2)
def _packmeta(meta, keys=None):
if not keys:
keys = sorted(meta.iterkeys())
return "".join("%s: %s\n" % (k, meta[k]) for k in keys)
class filelog(revlog.revlog):
def __init__(self, opener, path):
revlog.revlog.__init__(self, opener,
"/".join(("data", path + ".i")))
def read(self, node):
t = self.revision(node)
if not t.startswith('\1\n'):
return t
s = t.index('\1\n', 2)
return t[s + 2:]
def add(self, text, meta, transaction, link, p1=None, p2=None):
if meta or text.startswith('\1\n'):
text = "\1\n%s\1\n%s" % (_packmeta(meta), text)
return self.addrevision(text, transaction, link, p1, p2)
def renamed(self, node):
if self.parents(node)[0] != revlog.nullid:
return False
t = self.revision(node)
m = _parsemeta(t)[0]
if m and "copy" in m:
return (m["copy"], revlog.bin(m["copyrev"]))
return False
def size(self, rev):
"""return the size of a given revision"""
# for revisions with renames, we have to go the slow way
node = self.node(rev)
if self.renamed(node):
return len(self.read(node))
# XXX if self.read(node).startswith("\1\n"), this returns (size+4)
return revlog.revlog.size(self, rev)
def cmp(self, node, text):
"""compare text with a given file revision
returns True if text is different than what is stored.
"""
t = text
if text.startswith('\1\n'):
t = '\1\n\1\n' + text
samehashes = not revlog.revlog.cmp(self, node, t)
if samehashes:
return False
# renaming a file produces a different hash, even if the data
# remains unchanged. Check if it's the case (slow):
if self.renamed(node):
t2 = self.read(node)
return t2 != text
return True
def _file(self, f):
return filelog(self.opener, f)