diff -r 5ff1fc726848 -r c6bca38c1cbf eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/mercurial/demandimport.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/mercurial/demandimport.py Sat Jan 08 11:20:57 2011 +0530 @@ -0,0 +1,146 @@ +# demandimport.py - global demand-loading of modules for Mercurial +# +# Copyright 2006, 2007 Matt Mackall +# +# This software may be used and distributed according to the terms of the +# GNU General Public License version 2 or any later version. + +''' +demandimport - automatic demandloading of modules + +To enable this module, do: + + import demandimport; demandimport.enable() + +Imports of the following forms will be demand-loaded: + + import a, b.c + import a.b as c + from a import b,c # a will be loaded immediately + +These imports will not be delayed: + + from a import * + b = __import__(a) +''' + +import __builtin__ +_origimport = __import__ + +class _demandmod(object): + """module demand-loader and proxy""" + def __init__(self, name, globals, locals): + if '.' in name: + head, rest = name.split('.', 1) + after = [rest] + else: + head = name + after = [] + object.__setattr__(self, "_data", (head, globals, locals, after)) + object.__setattr__(self, "_module", None) + def _extend(self, name): + """add to the list of submodules to load""" + self._data[3].append(name) + def _load(self): + if not self._module: + head, globals, locals, after = self._data + mod = _origimport(head, globals, locals) + # load submodules + def subload(mod, p): + h, t = p, None + if '.' in p: + h, t = p.split('.', 1) + if not hasattr(mod, h): + setattr(mod, h, _demandmod(p, mod.__dict__, mod.__dict__)) + elif t: + subload(getattr(mod, h), t) + + for x in after: + subload(mod, x) + + # are we in the locals dictionary still? + if locals and locals.get(head) == self: + locals[head] = mod + object.__setattr__(self, "_module", mod) + + def __repr__(self): + if self._module: + return "" % self._data[0] + return "" % self._data[0] + def __call__(self, *args, **kwargs): + raise TypeError("%s object is not callable" % repr(self)) + def __getattribute__(self, attr): + if attr in ('_data', '_extend', '_load', '_module'): + return object.__getattribute__(self, attr) + self._load() + return getattr(self._module, attr) + def __setattr__(self, attr, val): + self._load() + setattr(self._module, attr, val) + +def _demandimport(name, globals=None, locals=None, fromlist=None, level=None): + if not locals or name in ignore or fromlist == ('*',): + # these cases we can't really delay + if level is None: + return _origimport(name, globals, locals, fromlist) + else: + return _origimport(name, globals, locals, fromlist, level) + elif not fromlist: + # import a [as b] + if '.' in name: # a.b + base, rest = name.split('.', 1) + # email.__init__ loading email.mime + if globals and globals.get('__name__', None) == base: + return _origimport(name, globals, locals, fromlist) + # if a is already demand-loaded, add b to its submodule list + if base in locals: + if isinstance(locals[base], _demandmod): + locals[base]._extend(rest) + return locals[base] + return _demandmod(name, globals, locals) + else: + if level is not None: + # from . import b,c,d or from .a import b,c,d + return _origimport(name, globals, locals, fromlist, level) + # from a import b,c,d + mod = _origimport(name, globals, locals) + # recurse down the module chain + for comp in name.split('.')[1:]: + if not hasattr(mod, comp): + setattr(mod, comp, _demandmod(comp, mod.__dict__, mod.__dict__)) + mod = getattr(mod, comp) + for x in fromlist: + # set requested submodules for demand load + if not(hasattr(mod, x)): + setattr(mod, x, _demandmod(x, mod.__dict__, locals)) + return mod + +ignore = [ + '_hashlib', + '_xmlplus', + 'fcntl', + 'win32com.gen_py', + '_winreg', # 2.7 mimetypes needs immediate ImportError + 'pythoncom', + # imported by tarfile, not available under Windows + 'pwd', + 'grp', + # imported by profile, itself imported by hotshot.stats, + # not available under Windows + 'resource', + # this trips up many extension authors + 'gtk', + # setuptools' pkg_resources.py expects "from __main__ import x" to + # raise ImportError if x not defined + '__main__', + '_ssl', # conditional imports in the stdlib, issue1964 + ] + +def enable(): + "enable global demand-loading of modules" + __builtin__.__import__ = _demandimport + +def disable(): + "disable global demand-loading of modules" + __builtin__.__import__ = _origimport +