revlog: fix revlogio.packentry corner case
We want to store version information about the revlog in the first
entry of its index. The code in packentry was using some heuristics
to detect whether this was the first entry, but these heuristics could
fail in some cases (e.g. rev 0 was empty; rev 1 descends directly from
the nullid and is stored as a delta).
We now give the revision number to packentry to avoid heuristics.
# repo.py - repository base classes for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
class RepoError(Exception):
pass
class NoCapability(RepoError):
pass
class repository(object):
def capable(self, name):
'''tell whether repo supports named capability.
return False if not supported.
if boolean capability, return True.
if string capability, return string.'''
if name in self.capabilities:
return True
name_eq = name + '='
for cap in self.capabilities:
if cap.startswith(name_eq):
return cap[len(name_eq):]
return False
def requirecap(self, name, purpose):
'''raise an exception if the given capability is not present'''
if not self.capable(name):
raise NoCapability(_('cannot %s; remote repository does not '
'support the %r capability') %
(purpose, name))