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
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
"""
These are Python 3.6+-only and keyword-only APIs that call `attr.s` and
`attr.ib` with different default values.
"""
from functools import partial
from attr.exceptions import UnannotatedAttributeError
from . import setters
from ._make import NOTHING, _frozen_setattrs, attrib, attrs
def define(
maybe_cls=None,
*,
these=None,
repr=None,
hash=None,
init=None,
slots=True,
frozen=False,
weakref_slot=True,
str=False,
auto_attribs=None,
kw_only=False,
cache_hash=False,
auto_exc=True,
eq=None,
order=False,
auto_detect=True,
getstate_setstate=None,
on_setattr=None,
field_transformer=None,
):
r"""
The only behavioral differences are the handling of the *auto_attribs*
option:
:param Optional[bool] auto_attribs: If set to `True` or `False`, it behaves
exactly like `attr.s`. If left `None`, `attr.s` will try to guess:
1. If any attributes are annotated and no unannotated `attr.ib`\ s
are found, it assumes *auto_attribs=True*.
2. Otherwise it assumes *auto_attribs=False* and tries to collect
`attr.ib`\ s.
and that mutable classes (``frozen=False``) validate on ``__setattr__``.
.. versionadded:: 20.1.0
"""
def do_it(cls, auto_attribs):
return attrs(
maybe_cls=cls,
these=these,
repr=repr,
hash=hash,
init=init,
slots=slots,
frozen=frozen,
weakref_slot=weakref_slot,
str=str,
auto_attribs=auto_attribs,
kw_only=kw_only,
cache_hash=cache_hash,
auto_exc=auto_exc,
eq=eq,
order=order,
auto_detect=auto_detect,
collect_by_mro=True,
getstate_setstate=getstate_setstate,
on_setattr=on_setattr,
field_transformer=field_transformer,
)
def wrap(cls):
"""
Making this a wrapper ensures this code runs during class creation.
We also ensure that frozen-ness of classes is inherited.
"""
nonlocal frozen, on_setattr
had_on_setattr = on_setattr not in (None, setters.NO_OP)
# By default, mutable classes validate on setattr.
if frozen is False and on_setattr is None:
on_setattr = setters.validate
# However, if we subclass a frozen class, we inherit the immutability
# and disable on_setattr.
for base_cls in cls.__bases__:
if base_cls.__setattr__ is _frozen_setattrs:
if had_on_setattr:
raise ValueError(
"Frozen classes can't use on_setattr "
"(frozen-ness was inherited)."
)
on_setattr = setters.NO_OP
break
if auto_attribs is not None:
return do_it(cls, auto_attribs)
try:
return do_it(cls, True)
except UnannotatedAttributeError:
return do_it(cls, False)
# maybe_cls's type depends on the usage of the decorator. It's a class
# if it's used as `@attrs` but ``None`` if used as `@attrs()`.
if maybe_cls is None:
return wrap
else:
return wrap(maybe_cls)
mutable = define
frozen = partial(define, frozen=True, on_setattr=None)
def field(
*,
default=NOTHING,
validator=None,
repr=True,
hash=None,
init=True,
metadata=None,
converter=None,
factory=None,
kw_only=False,
eq=None,
order=None,
on_setattr=None,
):
"""
Identical to `attr.ib`, except keyword-only and with some arguments
removed.
.. versionadded:: 20.1.0
"""
return attrib(
default=default,
validator=validator,
repr=repr,
hash=hash,
init=init,
metadata=metadata,
converter=converter,
factory=factory,
kw_only=kw_only,
eq=eq,
order=order,
on_setattr=on_setattr,
)
|
