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demandimport: patch __builtin__ instead of __builtins__...
Dirkjan Ochtman -
r7727:25fc4c62 default
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@@ -1,134 +1,135 b''
1 1 # demandimport.py - global demand-loading of modules for Mercurial
2 2 #
3 3 # Copyright 2006, 2007 Matt Mackall <mpm@selenic.com>
4 4 #
5 5 # This software may be used and distributed according to the terms
6 6 # of the GNU General Public License, incorporated herein by reference.
7 7
8 8 '''
9 9 demandimport - automatic demandloading of modules
10 10
11 11 To enable this module, do:
12 12
13 13 import demandimport; demandimport.enable()
14 14
15 15 Imports of the following forms will be demand-loaded:
16 16
17 17 import a, b.c
18 18 import a.b as c
19 19 from a import b,c # a will be loaded immediately
20 20
21 21 These imports will not be delayed:
22 22
23 23 from a import *
24 24 b = __import__(a)
25 25 '''
26 26
27 import __builtin__
27 28 _origimport = __import__
28 29
29 30 class _demandmod(object):
30 31 """module demand-loader and proxy"""
31 32 def __init__(self, name, globals, locals):
32 33 if '.' in name:
33 34 head, rest = name.split('.', 1)
34 35 after = [rest]
35 36 else:
36 37 head = name
37 38 after = []
38 39 object.__setattr__(self, "_data", (head, globals, locals, after))
39 40 object.__setattr__(self, "_module", None)
40 41 def _extend(self, name):
41 42 """add to the list of submodules to load"""
42 43 self._data[3].append(name)
43 44 def _load(self):
44 45 if not self._module:
45 46 head, globals, locals, after = self._data
46 47 mod = _origimport(head, globals, locals)
47 48 # load submodules
48 49 def subload(mod, p):
49 50 h, t = p, None
50 51 if '.' in p:
51 52 h, t = p.split('.', 1)
52 53 if not hasattr(mod, h):
53 54 setattr(mod, h, _demandmod(p, mod.__dict__, mod.__dict__))
54 55 elif t:
55 56 subload(getattr(mod, h), t)
56 57
57 58 for x in after:
58 59 subload(mod, x)
59 60
60 61 # are we in the locals dictionary still?
61 62 if locals and locals.get(head) == self:
62 63 locals[head] = mod
63 64 object.__setattr__(self, "_module", mod)
64 65
65 66 def __repr__(self):
66 67 if self._module:
67 68 return "<proxied module '%s'>" % self._data[0]
68 69 return "<unloaded module '%s'>" % self._data[0]
69 70 def __call__(self, *args, **kwargs):
70 71 raise TypeError("%s object is not callable" % repr(self))
71 72 def __getattribute__(self, attr):
72 73 if attr in ('_data', '_extend', '_load', '_module'):
73 74 return object.__getattribute__(self, attr)
74 75 self._load()
75 76 return getattr(self._module, attr)
76 77 def __setattr__(self, attr, val):
77 78 self._load()
78 79 setattr(self._module, attr, val)
79 80
80 81 def _demandimport(name, globals=None, locals=None, fromlist=None, level=None):
81 82 if not locals or name in ignore or fromlist == ('*',):
82 83 # these cases we can't really delay
83 84 return _origimport(name, globals, locals, fromlist)
84 85 elif not fromlist:
85 86 # import a [as b]
86 87 if '.' in name: # a.b
87 88 base, rest = name.split('.', 1)
88 89 # email.__init__ loading email.mime
89 90 if globals and globals.get('__name__', None) == base:
90 91 return _origimport(name, globals, locals, fromlist)
91 92 # if a is already demand-loaded, add b to its submodule list
92 93 if base in locals:
93 94 if isinstance(locals[base], _demandmod):
94 95 locals[base]._extend(rest)
95 96 return locals[base]
96 97 return _demandmod(name, globals, locals)
97 98 else:
98 99 if level is not None:
99 100 # from . import b,c,d or from .a import b,c,d
100 101 return _origimport(name, globals, locals, fromlist, level)
101 102 # from a import b,c,d
102 103 mod = _origimport(name, globals, locals)
103 104 # recurse down the module chain
104 105 for comp in name.split('.')[1:]:
105 106 if not hasattr(mod, comp):
106 107 setattr(mod, comp, _demandmod(comp, mod.__dict__, mod.__dict__))
107 108 mod = getattr(mod, comp)
108 109 for x in fromlist:
109 110 # set requested submodules for demand load
110 111 if not(hasattr(mod, x)):
111 112 setattr(mod, x, _demandmod(x, mod.__dict__, locals))
112 113 return mod
113 114
114 115 ignore = [
115 116 '_hashlib',
116 117 '_xmlplus',
117 118 'fcntl',
118 119 'win32com.gen_py',
119 120 # imported by tarfile, not available under Windows
120 121 'pwd',
121 122 'grp',
122 123 # imported by profile, itself imported by hotshot.stats,
123 124 # not available under Windows
124 125 'resource',
125 126 ]
126 127
127 128 def enable():
128 129 "enable global demand-loading of modules"
129 __builtins__["__import__"] = _demandimport
130 __builtin__.__import__ = _demandimport
130 131
131 132 def disable():
132 133 "disable global demand-loading of modules"
133 __builtins__["__import__"] = _origimport
134 __builtin__.__import__ = _origimport
134 135
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