--- a/hgdemandimport/demandimportpy2.py Mon Feb 21 13:08:28 2022 -0700
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,325 +0,0 @@
-# demandimport.py - global demand-loading of modules for Mercurial
-#
-# Copyright 2006, 2007 Olivia Mackall <olivia@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.
-
-'''
-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__ as builtins
-import contextlib
-import sys
-
-from . import tracing
-
-contextmanager = contextlib.contextmanager
-
-_origimport = __import__
-
-nothing = object()
-
-
-def _hgextimport(importfunc, name, globals, *args, **kwargs):
- try:
- return importfunc(name, globals, *args, **kwargs)
- except ImportError:
- if not globals:
- raise
- # extensions are loaded with "hgext_" prefix
- hgextname = 'hgext_%s' % name
- nameroot = hgextname.split('.', 1)[0]
- contextroot = globals.get('__name__', '').split('.', 1)[0]
- if nameroot != contextroot:
- raise
- # retry to import with "hgext_" prefix
- return importfunc(hgextname, globals, *args, **kwargs)
-
-
-class _demandmod:
- """module demand-loader and proxy
-
- Specify 1 as 'level' argument at construction, to import module
- relatively.
- """
-
- def __init__(self, name, globals, locals, level):
- if '.' in name:
- head, rest = name.split('.', 1)
- after = [rest]
- else:
- head = name
- after = []
- object.__setattr__(
- self, "_data", (head, globals, locals, after, level, set())
- )
- object.__setattr__(self, "_module", None)
-
- def _extend(self, name):
- """add to the list of submodules to load"""
- self._data[3].append(name)
-
- def _addref(self, name):
- """Record that the named module ``name`` imports this module.
-
- References to this proxy class having the name of this module will be
- replaced at module load time. We assume the symbol inside the importing
- module is identical to the "head" name of this module. We don't
- actually know if "as X" syntax is being used to change the symbol name
- because this information isn't exposed to __import__.
- """
- self._data[5].add(name)
-
- def _load(self):
- if not self._module:
- with tracing.log('demandimport %s', self._data[0]):
- head, globals, locals, after, level, modrefs = self._data
- mod = _hgextimport(
- _origimport, head, globals, locals, None, level
- )
- if mod is self:
- # In this case, _hgextimport() above should imply
- # _demandimport(). Otherwise, _hgextimport() never
- # returns _demandmod. This isn't intentional behavior,
- # in fact. (see also issue5304 for detail)
- #
- # If self._module is already bound at this point, self
- # should be already _load()-ed while _hgextimport().
- # Otherwise, there is no way to import actual module
- # as expected, because (re-)invoking _hgextimport()
- # should cause same result.
- # This is reason why _load() returns without any more
- # setup but assumes self to be already bound.
- mod = self._module
- assert mod and mod is not self, "%s, %s" % (self, mod)
- return
-
- # load submodules
- def subload(mod, p):
- h, t = p, None
- if '.' in p:
- h, t = p.split('.', 1)
- if getattr(mod, h, nothing) is nothing:
- setattr(
- mod,
- h,
- _demandmod(p, mod.__dict__, mod.__dict__, level=1),
- )
- elif t:
- subload(getattr(mod, h), t)
-
- for x in after:
- subload(mod, x)
-
- # Replace references to this proxy instance with the
- # actual module.
- if locals:
- if locals.get(head) is self:
- locals[head] = mod
- elif locals.get(head + 'mod') is self:
- locals[head + 'mod'] = mod
-
- for modname in modrefs:
- modref = sys.modules.get(modname, None)
- if modref and getattr(modref, head, None) is self:
- setattr(modref, head, mod)
-
- object.__setattr__(self, "_module", mod)
-
- def __repr__(self):
- if self._module:
- return "<proxied module '%s'>" % self._data[0]
- return "<unloaded module '%s'>" % self._data[0]
-
- def __call__(self, *args, **kwargs):
- raise TypeError("%s object is not callable" % repr(self))
-
- def __getattr__(self, attr):
- self._load()
- return getattr(self._module, attr)
-
- def __setattr__(self, attr, val):
- self._load()
- setattr(self._module, attr, val)
-
- @property
- def __dict__(self):
- self._load()
- return self._module.__dict__
-
- @property
- def __doc__(self):
- self._load()
- return self._module.__doc__
-
-
-_pypy = '__pypy__' in sys.builtin_module_names
-
-
-def _demandimport(name, globals=None, locals=None, fromlist=None, level=-1):
- if locals is None or name in ignores or fromlist == ('*',):
- # these cases we can't really delay
- return _hgextimport(_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, level)
- # 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, level)
- else:
- # There is a fromlist.
- # from a import b,c,d
- # from . import b,c,d
- # from .a import b,c,d
-
- # level == -1: relative and absolute attempted (Python 2 only).
- # level >= 0: absolute only (Python 2 w/ absolute_import and Python 3).
- # The modern Mercurial convention is to use absolute_import everywhere,
- # so modern Mercurial code will have level >= 0.
-
- # The name of the module the import statement is located in.
- globalname = globals.get('__name__')
-
- def processfromitem(mod, attr):
- """Process an imported symbol in the import statement.
-
- If the symbol doesn't exist in the parent module, and if the
- parent module is a package, it must be a module. We set missing
- modules up as _demandmod instances.
- """
- symbol = getattr(mod, attr, nothing)
- nonpkg = getattr(mod, '__path__', nothing) is nothing
- if symbol is nothing:
- if nonpkg:
- # do not try relative import, which would raise ValueError,
- # and leave unknown attribute as the default __import__()
- # would do. the missing attribute will be detected later
- # while processing the import statement.
- return
- mn = '%s.%s' % (mod.__name__, attr)
- if mn in ignores:
- importfunc = _origimport
- else:
- importfunc = _demandmod
- symbol = importfunc(attr, mod.__dict__, locals, level=1)
- setattr(mod, attr, symbol)
-
- # Record the importing module references this symbol so we can
- # replace the symbol with the actual module instance at load
- # time.
- if globalname and isinstance(symbol, _demandmod):
- symbol._addref(globalname)
-
- def chainmodules(rootmod, modname):
- # recurse down the module chain, and return the leaf module
- mod = rootmod
- for comp in modname.split('.')[1:]:
- obj = getattr(mod, comp, nothing)
- if obj is nothing:
- obj = _demandmod(comp, mod.__dict__, mod.__dict__, level=1)
- setattr(mod, comp, obj)
- elif mod.__name__ + '.' + comp in sys.modules:
- # prefer loaded module over attribute (issue5617)
- obj = sys.modules[mod.__name__ + '.' + comp]
- mod = obj
- return mod
-
- if level >= 0:
- if name:
- # "from a import b" or "from .a import b" style
- rootmod = _hgextimport(
- _origimport, name, globals, locals, level=level
- )
- mod = chainmodules(rootmod, name)
- elif _pypy:
- # PyPy's __import__ throws an exception if invoked
- # with an empty name and no fromlist. Recreate the
- # desired behaviour by hand.
- mn = globalname
- mod = sys.modules[mn]
- if getattr(mod, '__path__', nothing) is nothing:
- mn = mn.rsplit('.', 1)[0]
- mod = sys.modules[mn]
- if level > 1:
- mn = mn.rsplit('.', level - 1)[0]
- mod = sys.modules[mn]
- else:
- mod = _hgextimport(
- _origimport, name, globals, locals, level=level
- )
-
- for x in fromlist:
- processfromitem(mod, x)
-
- return mod
-
- # But, we still need to support lazy loading of standard library and 3rd
- # party modules. So handle level == -1.
- mod = _hgextimport(_origimport, name, globals, locals)
- mod = chainmodules(mod, name)
-
- for x in fromlist:
- processfromitem(mod, x)
-
- return mod
-
-
-ignores = set()
-
-
-def init(ignoreset):
- global ignores
- ignores = ignoreset
-
-
-def isenabled():
- return builtins.__import__ == _demandimport
-
-
-def enable():
- """enable global demand-loading of modules"""
- builtins.__import__ = _demandimport
-
-
-def disable():
- """disable global demand-loading of modules"""
- builtins.__import__ = _origimport
-
-
-@contextmanager
-def deactivated():
- """context manager for disabling demandimport in 'with' blocks"""
- demandenabled = isenabled()
- if demandenabled:
- disable()
-
- try:
- yield
- finally:
- if demandenabled:
- enable()