revlog: break up compression of large deltas
Python's zlib apparently makes an internal copy of strings passed to
compress(). To avoid this, compress strings 1M at a time, then join
them at the end if the result would be smaller than the original.
For initial commits of large but compressible files, this cuts peak
memory usage nearly in half.
# Copyright (C) 2007 Brendan Cully <brendan@kublai.com>
# This file is published under the GNU GPL.
'''allow user-defined command aliases
To use, create entries in your hgrc of the form
[alias]
mycmd = cmd --args
'''
from mercurial.cmdutil import findcmd, UnknownCommand, AmbiguousCommand
from mercurial import commands
cmdtable = {}
class RecursiveCommand(Exception): pass
class lazycommand(object):
'''defer command lookup until needed, so that extensions loaded
after alias can be aliased'''
def __init__(self, ui, name, target):
self._ui = ui
self._name = name
self._target = target
self._cmd = None
def __len__(self):
self._resolve()
return len(self._cmd)
def __getitem__(self, key):
self._resolve()
return self._cmd[key]
def __iter__(self):
self._resolve()
return self._cmd.__iter__()
def _resolve(self):
if self._cmd is not None:
return
try:
self._cmd = findcmd(self._ui, self._target, commands.table)[1]
if self._cmd == self:
raise RecursiveCommand()
if self._target in commands.norepo.split(' '):
commands.norepo += ' %s' % self._name
return
except UnknownCommand:
msg = '*** [alias] %s: command %s is unknown' % \
(self._name, self._target)
except AmbiguousCommand:
msg = '*** [alias] %s: command %s is ambiguous' % \
(self._name, self._target)
except RecursiveCommand:
msg = '*** [alias] %s: circular dependency on %s' % \
(self._name, self._target)
def nocmd(*args, **opts):
self._ui.warn(msg + '\n')
return 1
nocmd.__doc__ = msg
self._cmd = (nocmd, [], '')
commands.norepo += ' %s' % self._name
def uisetup(ui):
for cmd, target in ui.configitems('alias'):
if not target:
ui.warn('*** [alias] %s: no definition\n' % cmd)
continue
args = target.split(' ')
tcmd = args.pop(0)
if args:
ui.setconfig('defaults', cmd, ' '.join(args))
cmdtable[cmd] = lazycommand(ui, cmd, tcmd)