##// END OF EJS Templates
Make demandimport pass all tests on python2.5.
Brendan Cully -
r3903:f9136599 default
parent child Browse files
Show More
@@ -1,104 +1,109 b''
1 # demandimport.py - global demand-loading of modules for Mercurial
1 # demandimport.py - global demand-loading of modules for Mercurial
2 #
2 #
3 # Copyright 2006 Matt Mackall <mpm@selenic.com>
3 # Copyright 2006 Matt Mackall <mpm@selenic.com>
4 #
4 #
5 # This software may be used and distributed according to the terms
5 # This software may be used and distributed according to the terms
6 # of the GNU General Public License, incorporated herein by reference.
6 # of the GNU General Public License, incorporated herein by reference.
7
7
8 '''
8 '''
9 demandimport - automatic demandloading of modules
9 demandimport - automatic demandloading of modules
10
10
11 To enable this module, do:
11 To enable this module, do:
12
12
13 import demandimport; demandimport.enable()
13 import demandimport; demandimport.enable()
14
14
15 Imports of the following forms will be demand-loaded:
15 Imports of the following forms will be demand-loaded:
16
16
17 import a, b.c
17 import a, b.c
18 import a.b as c
18 import a.b as c
19 from a import b,c # a will be loaded immediately
19 from a import b,c # a will be loaded immediately
20
20
21 These imports will not be delayed:
21 These imports will not be delayed:
22
22
23 from a import *
23 from a import *
24 b = __import__(a)
24 b = __import__(a)
25 '''
25 '''
26
26
27 _origimport = __import__
27 _origimport = __import__
28
28
29 class _demandmod(object):
29 class _demandmod(object):
30 """module demand-loader and proxy"""
30 """module demand-loader and proxy"""
31 def __init__(self, name, globals, locals):
31 def __init__(self, name, globals, locals):
32 if '.' in name:
32 if '.' in name:
33 head, rest = name.split('.', 1)
33 head, rest = name.split('.', 1)
34 after = [rest]
34 after = [rest]
35 else:
35 else:
36 head = name
36 head = name
37 after = []
37 after = []
38 object.__setattr__(self, "_data", (head, globals, locals, after))
38 object.__setattr__(self, "_data", (head, globals, locals, after))
39 object.__setattr__(self, "_module", None)
39 object.__setattr__(self, "_module", None)
40 def _extend(self, name):
40 def _extend(self, name):
41 """add to the list of submodules to load"""
41 """add to the list of submodules to load"""
42 self._data[3].append(name)
42 self._data[3].append(name)
43 def _load(self):
43 def _load(self):
44 if not self._module:
44 if not self._module:
45 head, globals, locals, after = self._data
45 head, globals, locals, after = self._data
46 mod = _origimport(head, globals, locals)
46 mod = _origimport(head, globals, locals)
47 # load submodules
47 # load submodules
48 for x in after:
48 for x in after:
49 hx = x
49 hx = x
50 if '.' in x:
50 if '.' in x:
51 hx = x.split('.')[0]
51 hx = x.split('.')[0]
52 if not hasattr(mod, hx):
52 if not hasattr(mod, hx):
53 setattr(mod, hx, _demandmod(x, mod.__dict__, mod.__dict__))
53 setattr(mod, hx, _demandmod(x, mod.__dict__, mod.__dict__))
54 # are we in the locals dictionary still?
54 # are we in the locals dictionary still?
55 if locals and locals.get(head) == self:
55 if locals and locals.get(head) == self:
56 locals[head] = mod
56 locals[head] = mod
57 object.__setattr__(self, "_module", mod)
57 object.__setattr__(self, "_module", mod)
58 def __repr__(self):
58 def __repr__(self):
59 return "<unloaded module '%s'>" % self._data[0]
59 return "<unloaded module '%s'>" % self._data[0]
60 def __call__(self, *args, **kwargs):
60 def __call__(self, *args, **kwargs):
61 raise TypeError("'unloaded module' object is not callable")
61 raise TypeError("'unloaded module' object is not callable")
62 def __getattr__(self, attr):
62 def __getattribute__(self, attr):
63 if attr in ('_data', '_extend', '_load', '_module'):
64 return object.__getattribute__(self, attr)
63 self._load()
65 self._load()
64 return getattr(self._module, attr)
66 return getattr(self._module, attr)
65 def __setattr__(self, attr, val):
67 def __setattr__(self, attr, val):
66 self._load()
68 self._load()
67 setattr(self._module, attr, val)
69 setattr(self._module, attr, val)
68
70
69 def _demandimport(name, globals=None, locals=None, fromlist=None):
71 def _demandimport(name, globals=None, locals=None, fromlist=None):
70 if not locals or name in ignore or fromlist == ('*',):
72 if not locals or name in ignore or fromlist == ('*',):
71 # these cases we can't really delay
73 # these cases we can't really delay
72 return _origimport(name, globals, locals, fromlist)
74 return _origimport(name, globals, locals, fromlist)
73 elif not fromlist:
75 elif not fromlist:
74 # import a [as b]
76 # import a [as b]
75 if '.' in name: # a.b
77 if '.' in name: # a.b
76 base, rest = name.split('.', 1)
78 base, rest = name.split('.', 1)
79 # email.__init__ loading email.mime
80 if globals and globals.get('__name__', None) == base:
81 return _origimport(name, globals, locals, fromlist)
77 # if a is already demand-loaded, add b to its submodule list
82 # if a is already demand-loaded, add b to its submodule list
78 if base in locals:
83 if base in locals:
79 if isinstance(locals[base], _demandmod):
84 if isinstance(locals[base], _demandmod):
80 locals[base]._extend(rest)
85 locals[base]._extend(rest)
81 return locals[base]
86 return locals[base]
82 return _demandmod(name, globals, locals)
87 return _demandmod(name, globals, locals)
83 else:
88 else:
84 # from a import b,c,d
89 # from a import b,c,d
85 mod = _origimport(name, globals, locals)
90 mod = _origimport(name, globals, locals)
86 # recurse down the module chain
91 # recurse down the module chain
87 for comp in name.split('.')[1:]:
92 for comp in name.split('.')[1:]:
88 mod = getattr(mod, comp)
93 mod = getattr(mod, comp)
89 for x in fromlist:
94 for x in fromlist:
90 # set requested submodules for demand load
95 # set requested submodules for demand load
91 if not(hasattr(mod, x)):
96 if not(hasattr(mod, x)):
92 setattr(mod, x, _demandmod(x, mod.__dict__, mod.__dict__))
97 setattr(mod, x, _demandmod(x, mod.__dict__, mod.__dict__))
93 return mod
98 return mod
94
99
95 ignore = ['_hashlib', 'email.mime']
100 ignore = []
96
101
97 def enable():
102 def enable():
98 "enable global demand-loading of modules"
103 "enable global demand-loading of modules"
99 __builtins__["__import__"] = _demandimport
104 __builtins__["__import__"] = _demandimport
100
105
101 def disable():
106 def disable():
102 "disable global demand-loading of modules"
107 "disable global demand-loading of modules"
103 __builtins__["__import__"] = _origimport
108 __builtins__["__import__"] = _origimport
104
109
General Comments 0
You need to be logged in to leave comments. Login now