-
Notifications
You must be signed in to change notification settings - Fork 0
/
funcwrap.py
103 lines (82 loc) · 3 KB
/
funcwrap.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
import inspect
import functools
__version__ = '0.0.1'
def wraps(func, wrapper=None):
"""
Return a wrapper around ``wrapper`` that preserves the signature of
the original function ``func`` exactly.
Args:
func (function): function to be imitated
wrapper (function): function to be called actually
Returns:
A function that has the same signature, default arguments, and
appearance as as ``func`` but calls ``wrapper``, not ``func``.
Example:
Defining a decorator for debug output::
from funcwrap import wraps
def trace(func):
"Trace a function call."
@wraps(func)
def wrapper(*args, **kwargs):
print('TRACE:', func.__name__, args, kwargs)
return func(*args, **kwargs)
return wrapper
And using it as follows::
class Window(QWidget):
...
@trace
def on_exit_clicked(self):
pass
# works seemlessly:
exit_action.triggered.connect(window.on_exit_clicked)
"""
if wrapper is None:
return functools.partial(wraps, func)
signature = inspect.signature(func)
argspec = inspect.getfullargspec(func)
funcsig = list(argspec.args)
callargs = list(argspec.args)
if argspec.varargs:
funcsig.append('*' + argspec.varargs)
callargs.append('*' + argspec.varargs)
elif argspec.kwonlyargs:
funcsig.append('*')
for a in argspec.kwonlyargs:
funcsig.append('%s' % a)
callargs.append('%s=%s' % (a, a))
if argspec.varkw:
funcsig.append('**' + argspec.varkw)
callargs.append('**' + argspec.varkw)
num_pos_only = next(
(i for i, p in enumerate(signature.parameters.values())
if p.kind.name != 'POSITIONAL_ONLY'),
len(signature.parameters))
if num_pos_only > 0:
funcsig.insert(num_pos_only, '/')
wrapper_name = '__call__'
while wrapper_name in signature.parameters:
wrapper_name += '_'
source = 'lambda {funcsig}: {callee}({callargs})'.format(
callee=wrapper_name,
funcsig=', '.join(funcsig),
callargs=', '.join(callargs),
)
try:
sourcefile = inspect.getsourcefile(func)
filename = '<decorator {}>'.format(sourcefile)
except TypeError:
filename = '<decorator>'
code = compile(source, filename, 'eval')
fun = eval(code, {wrapper_name: wrapper})
fun.__name__ = getattr(func, '__name__', '<unknown>')
fun.__doc__ = getattr(func, '__doc__', '')
fun.__dict__ = getattr(func, '__dict__', {}).copy()
fun.__defaults__ = argspec.defaults
fun.__kwdefaults__ = argspec.kwonlydefaults
fun.__annotations__ = argspec.annotations
fun.__module__ = getattr(func, '__module__', None)
fun.__wrapped__ = func
fun.__source__ = source
if hasattr(func, '__qualname__'):
fun.__qualname__ = func.__qualname__
return fun