Show More
@@ -1,1059 +1,1059 b'' | |||||
1 | from __future__ import absolute_import, division, print_function |
|
1 | from __future__ import absolute_import, division, print_function | |
2 |
|
2 | |||
3 | import hashlib |
|
3 | import hashlib | |
4 | import linecache |
|
4 | import linecache | |
5 |
|
5 | |||
6 | from operator import itemgetter |
|
6 | from operator import itemgetter | |
7 |
|
7 | |||
8 | from . import _config |
|
8 | from . import _config | |
9 | from ._compat import PY2, iteritems, isclass, iterkeys, metadata_proxy |
|
9 | from ._compat import PY2, iteritems, isclass, iterkeys, metadata_proxy | |
10 | from .exceptions import ( |
|
10 | from .exceptions import ( | |
11 | DefaultAlreadySetError, |
|
11 | DefaultAlreadySetError, | |
12 | FrozenInstanceError, |
|
12 | FrozenInstanceError, | |
13 | NotAnAttrsClassError, |
|
13 | NotAnAttrsClassError, | |
14 | ) |
|
14 | ) | |
15 |
|
15 | |||
16 |
|
16 | |||
17 | # This is used at least twice, so cache it here. |
|
17 | # This is used at least twice, so cache it here. | |
18 | _obj_setattr = object.__setattr__ |
|
18 | _obj_setattr = object.__setattr__ | |
19 | _init_convert_pat = "__attr_convert_{}" |
|
19 | _init_convert_pat = "__attr_convert_{}" | |
20 | _init_factory_pat = "__attr_factory_{}" |
|
20 | _init_factory_pat = "__attr_factory_{}" | |
21 | _tuple_property_pat = " {attr_name} = property(itemgetter({index}))" |
|
21 | _tuple_property_pat = " {attr_name} = property(itemgetter({index}))" | |
22 | _empty_metadata_singleton = metadata_proxy({}) |
|
22 | _empty_metadata_singleton = metadata_proxy({}) | |
23 |
|
23 | |||
24 |
|
24 | |||
25 | class _Nothing(object): |
|
25 | class _Nothing(object): | |
26 | """ |
|
26 | """ | |
27 | Sentinel class to indicate the lack of a value when ``None`` is ambiguous. |
|
27 | Sentinel class to indicate the lack of a value when ``None`` is ambiguous. | |
28 |
|
28 | |||
29 | All instances of `_Nothing` are equal. |
|
29 | All instances of `_Nothing` are equal. | |
30 | """ |
|
30 | """ | |
31 | def __copy__(self): |
|
31 | def __copy__(self): | |
32 | return self |
|
32 | return self | |
33 |
|
33 | |||
34 | def __deepcopy__(self, _): |
|
34 | def __deepcopy__(self, _): | |
35 | return self |
|
35 | return self | |
36 |
|
36 | |||
37 | def __eq__(self, other): |
|
37 | def __eq__(self, other): | |
38 | return other.__class__ == _Nothing |
|
38 | return other.__class__ == _Nothing | |
39 |
|
39 | |||
40 | def __ne__(self, other): |
|
40 | def __ne__(self, other): | |
41 | return not self == other |
|
41 | return not self == other | |
42 |
|
42 | |||
43 | def __repr__(self): |
|
43 | def __repr__(self): | |
44 | return "NOTHING" |
|
44 | return "NOTHING" | |
45 |
|
45 | |||
46 | def __hash__(self): |
|
46 | def __hash__(self): | |
47 | return 0xdeadbeef |
|
47 | return 0xdeadbeef | |
48 |
|
48 | |||
49 |
|
49 | |||
50 | NOTHING = _Nothing() |
|
50 | NOTHING = _Nothing() | |
51 | """ |
|
51 | """ | |
52 | Sentinel to indicate the lack of a value when ``None`` is ambiguous. |
|
52 | Sentinel to indicate the lack of a value when ``None`` is ambiguous. | |
53 | """ |
|
53 | """ | |
54 |
|
54 | |||
55 |
|
55 | |||
56 | def attr(default=NOTHING, validator=None, |
|
56 | def attr(default=NOTHING, validator=None, | |
57 | repr=True, cmp=True, hash=None, init=True, |
|
57 | repr=True, cmp=True, hash=None, init=True, | |
58 | convert=None, metadata={}): |
|
58 | convert=None, metadata={}): | |
59 | """ |
|
59 | r""" | |
60 | Create a new attribute on a class. |
|
60 | Create a new attribute on a class. | |
61 |
|
61 | |||
62 | .. warning:: |
|
62 | .. warning:: | |
63 |
|
63 | |||
64 | Does *not* do anything unless the class is also decorated with |
|
64 | Does *not* do anything unless the class is also decorated with | |
65 | :func:`attr.s`! |
|
65 | :func:`attr.s`! | |
66 |
|
66 | |||
67 | :param default: A value that is used if an ``attrs``-generated ``__init__`` |
|
67 | :param default: A value that is used if an ``attrs``-generated ``__init__`` | |
68 | is used and no value is passed while instantiating or the attribute is |
|
68 | is used and no value is passed while instantiating or the attribute is | |
69 | excluded using ``init=False``. |
|
69 | excluded using ``init=False``. | |
70 |
|
70 | |||
71 | If the value is an instance of :class:`Factory`, its callable will be |
|
71 | If the value is an instance of :class:`Factory`, its callable will be | |
72 | used to construct a new value (useful for mutable datatypes like lists |
|
72 | used to construct a new value (useful for mutable datatypes like lists | |
73 | or dicts). |
|
73 | or dicts). | |
74 |
|
74 | |||
75 | If a default is not set (or set manually to ``attr.NOTHING``), a value |
|
75 | If a default is not set (or set manually to ``attr.NOTHING``), a value | |
76 | *must* be supplied when instantiating; otherwise a :exc:`TypeError` |
|
76 | *must* be supplied when instantiating; otherwise a :exc:`TypeError` | |
77 | will be raised. |
|
77 | will be raised. | |
78 |
|
78 | |||
79 | The default can also be set using decorator notation as shown below. |
|
79 | The default can also be set using decorator notation as shown below. | |
80 |
|
80 | |||
81 | :type default: Any value. |
|
81 | :type default: Any value. | |
82 |
|
82 | |||
83 | :param validator: :func:`callable` that is called by ``attrs``-generated |
|
83 | :param validator: :func:`callable` that is called by ``attrs``-generated | |
84 | ``__init__`` methods after the instance has been initialized. They |
|
84 | ``__init__`` methods after the instance has been initialized. They | |
85 | receive the initialized instance, the :class:`Attribute`, and the |
|
85 | receive the initialized instance, the :class:`Attribute`, and the | |
86 | passed value. |
|
86 | passed value. | |
87 |
|
87 | |||
88 | The return value is *not* inspected so the validator has to throw an |
|
88 | The return value is *not* inspected so the validator has to throw an | |
89 | exception itself. |
|
89 | exception itself. | |
90 |
|
90 | |||
91 | If a ``list`` is passed, its items are treated as validators and must |
|
91 | If a ``list`` is passed, its items are treated as validators and must | |
92 | all pass. |
|
92 | all pass. | |
93 |
|
93 | |||
94 | Validators can be globally disabled and re-enabled using |
|
94 | Validators can be globally disabled and re-enabled using | |
95 | :func:`get_run_validators`. |
|
95 | :func:`get_run_validators`. | |
96 |
|
96 | |||
97 | The validator can also be set using decorator notation as shown below. |
|
97 | The validator can also be set using decorator notation as shown below. | |
98 |
|
98 | |||
99 | :type validator: ``callable`` or a ``list`` of ``callable``\ s. |
|
99 | :type validator: ``callable`` or a ``list`` of ``callable``\ s. | |
100 |
|
100 | |||
101 | :param bool repr: Include this attribute in the generated ``__repr__`` |
|
101 | :param bool repr: Include this attribute in the generated ``__repr__`` | |
102 | method. |
|
102 | method. | |
103 | :param bool cmp: Include this attribute in the generated comparison methods |
|
103 | :param bool cmp: Include this attribute in the generated comparison methods | |
104 | (``__eq__`` et al). |
|
104 | (``__eq__`` et al). | |
105 | :param hash: Include this attribute in the generated ``__hash__`` |
|
105 | :param hash: Include this attribute in the generated ``__hash__`` | |
106 | method. If ``None`` (default), mirror *cmp*'s value. This is the |
|
106 | method. If ``None`` (default), mirror *cmp*'s value. This is the | |
107 | correct behavior according the Python spec. Setting this value to |
|
107 | correct behavior according the Python spec. Setting this value to | |
108 | anything else than ``None`` is *discouraged*. |
|
108 | anything else than ``None`` is *discouraged*. | |
109 | :type hash: ``bool`` or ``None`` |
|
109 | :type hash: ``bool`` or ``None`` | |
110 | :param bool init: Include this attribute in the generated ``__init__`` |
|
110 | :param bool init: Include this attribute in the generated ``__init__`` | |
111 | method. It is possible to set this to ``False`` and set a default |
|
111 | method. It is possible to set this to ``False`` and set a default | |
112 | value. In that case this attributed is unconditionally initialized |
|
112 | value. In that case this attributed is unconditionally initialized | |
113 | with the specified default value or factory. |
|
113 | with the specified default value or factory. | |
114 | :param callable convert: :func:`callable` that is called by |
|
114 | :param callable convert: :func:`callable` that is called by | |
115 | ``attrs``-generated ``__init__`` methods to convert attribute's value |
|
115 | ``attrs``-generated ``__init__`` methods to convert attribute's value | |
116 | to the desired format. It is given the passed-in value, and the |
|
116 | to the desired format. It is given the passed-in value, and the | |
117 | returned value will be used as the new value of the attribute. The |
|
117 | returned value will be used as the new value of the attribute. The | |
118 | value is converted before being passed to the validator, if any. |
|
118 | value is converted before being passed to the validator, if any. | |
119 | :param metadata: An arbitrary mapping, to be used by third-party |
|
119 | :param metadata: An arbitrary mapping, to be used by third-party | |
120 | components. See :ref:`extending_metadata`. |
|
120 | components. See :ref:`extending_metadata`. | |
121 |
|
121 | |||
122 | .. versionchanged:: 17.1.0 *validator* can be a ``list`` now. |
|
122 | .. versionchanged:: 17.1.0 *validator* can be a ``list`` now. | |
123 | .. versionchanged:: 17.1.0 |
|
123 | .. versionchanged:: 17.1.0 | |
124 | *hash* is ``None`` and therefore mirrors *cmp* by default . |
|
124 | *hash* is ``None`` and therefore mirrors *cmp* by default . | |
125 | """ |
|
125 | """ | |
126 | if hash is not None and hash is not True and hash is not False: |
|
126 | if hash is not None and hash is not True and hash is not False: | |
127 | raise TypeError( |
|
127 | raise TypeError( | |
128 | "Invalid value for hash. Must be True, False, or None." |
|
128 | "Invalid value for hash. Must be True, False, or None." | |
129 | ) |
|
129 | ) | |
130 | return _CountingAttr( |
|
130 | return _CountingAttr( | |
131 | default=default, |
|
131 | default=default, | |
132 | validator=validator, |
|
132 | validator=validator, | |
133 | repr=repr, |
|
133 | repr=repr, | |
134 | cmp=cmp, |
|
134 | cmp=cmp, | |
135 | hash=hash, |
|
135 | hash=hash, | |
136 | init=init, |
|
136 | init=init, | |
137 | convert=convert, |
|
137 | convert=convert, | |
138 | metadata=metadata, |
|
138 | metadata=metadata, | |
139 | ) |
|
139 | ) | |
140 |
|
140 | |||
141 |
|
141 | |||
142 | def _make_attr_tuple_class(cls_name, attr_names): |
|
142 | def _make_attr_tuple_class(cls_name, attr_names): | |
143 | """ |
|
143 | """ | |
144 | Create a tuple subclass to hold `Attribute`s for an `attrs` class. |
|
144 | Create a tuple subclass to hold `Attribute`s for an `attrs` class. | |
145 |
|
145 | |||
146 | The subclass is a bare tuple with properties for names. |
|
146 | The subclass is a bare tuple with properties for names. | |
147 |
|
147 | |||
148 | class MyClassAttributes(tuple): |
|
148 | class MyClassAttributes(tuple): | |
149 | __slots__ = () |
|
149 | __slots__ = () | |
150 | x = property(itemgetter(0)) |
|
150 | x = property(itemgetter(0)) | |
151 | """ |
|
151 | """ | |
152 | attr_class_name = "{}Attributes".format(cls_name) |
|
152 | attr_class_name = "{}Attributes".format(cls_name) | |
153 | attr_class_template = [ |
|
153 | attr_class_template = [ | |
154 | "class {}(tuple):".format(attr_class_name), |
|
154 | "class {}(tuple):".format(attr_class_name), | |
155 | " __slots__ = ()", |
|
155 | " __slots__ = ()", | |
156 | ] |
|
156 | ] | |
157 | if attr_names: |
|
157 | if attr_names: | |
158 | for i, attr_name in enumerate(attr_names): |
|
158 | for i, attr_name in enumerate(attr_names): | |
159 | attr_class_template.append(_tuple_property_pat.format( |
|
159 | attr_class_template.append(_tuple_property_pat.format( | |
160 | index=i, |
|
160 | index=i, | |
161 | attr_name=attr_name, |
|
161 | attr_name=attr_name, | |
162 | )) |
|
162 | )) | |
163 | else: |
|
163 | else: | |
164 | attr_class_template.append(" pass") |
|
164 | attr_class_template.append(" pass") | |
165 | globs = {"itemgetter": itemgetter} |
|
165 | globs = {"itemgetter": itemgetter} | |
166 | eval(compile("\n".join(attr_class_template), "", "exec"), globs) |
|
166 | eval(compile("\n".join(attr_class_template), "", "exec"), globs) | |
167 | return globs[attr_class_name] |
|
167 | return globs[attr_class_name] | |
168 |
|
168 | |||
169 |
|
169 | |||
170 | def _transform_attrs(cls, these): |
|
170 | def _transform_attrs(cls, these): | |
171 | """ |
|
171 | """ | |
172 | Transforms all `_CountingAttr`s on a class into `Attribute`s and saves the |
|
172 | Transforms all `_CountingAttr`s on a class into `Attribute`s and saves the | |
173 | list in `__attrs_attrs__`. |
|
173 | list in `__attrs_attrs__`. | |
174 |
|
174 | |||
175 | If *these* is passed, use that and don't look for them on the class. |
|
175 | If *these* is passed, use that and don't look for them on the class. | |
176 | """ |
|
176 | """ | |
177 | super_cls = [] |
|
177 | super_cls = [] | |
178 | for c in reversed(cls.__mro__[1:-1]): |
|
178 | for c in reversed(cls.__mro__[1:-1]): | |
179 | sub_attrs = getattr(c, "__attrs_attrs__", None) |
|
179 | sub_attrs = getattr(c, "__attrs_attrs__", None) | |
180 | if sub_attrs is not None: |
|
180 | if sub_attrs is not None: | |
181 | super_cls.extend(a for a in sub_attrs if a not in super_cls) |
|
181 | super_cls.extend(a for a in sub_attrs if a not in super_cls) | |
182 | if these is None: |
|
182 | if these is None: | |
183 | ca_list = [(name, attr) |
|
183 | ca_list = [(name, attr) | |
184 | for name, attr |
|
184 | for name, attr | |
185 | in cls.__dict__.items() |
|
185 | in cls.__dict__.items() | |
186 | if isinstance(attr, _CountingAttr)] |
|
186 | if isinstance(attr, _CountingAttr)] | |
187 | else: |
|
187 | else: | |
188 | ca_list = [(name, ca) |
|
188 | ca_list = [(name, ca) | |
189 | for name, ca |
|
189 | for name, ca | |
190 | in iteritems(these)] |
|
190 | in iteritems(these)] | |
191 |
|
191 | |||
192 | non_super_attrs = [ |
|
192 | non_super_attrs = [ | |
193 | Attribute.from_counting_attr(name=attr_name, ca=ca) |
|
193 | Attribute.from_counting_attr(name=attr_name, ca=ca) | |
194 | for attr_name, ca |
|
194 | for attr_name, ca | |
195 | in sorted(ca_list, key=lambda e: e[1].counter) |
|
195 | in sorted(ca_list, key=lambda e: e[1].counter) | |
196 | ] |
|
196 | ] | |
197 | attr_names = [a.name for a in super_cls + non_super_attrs] |
|
197 | attr_names = [a.name for a in super_cls + non_super_attrs] | |
198 |
|
198 | |||
199 | AttrsClass = _make_attr_tuple_class(cls.__name__, attr_names) |
|
199 | AttrsClass = _make_attr_tuple_class(cls.__name__, attr_names) | |
200 |
|
200 | |||
201 | cls.__attrs_attrs__ = AttrsClass(super_cls + [ |
|
201 | cls.__attrs_attrs__ = AttrsClass(super_cls + [ | |
202 | Attribute.from_counting_attr(name=attr_name, ca=ca) |
|
202 | Attribute.from_counting_attr(name=attr_name, ca=ca) | |
203 | for attr_name, ca |
|
203 | for attr_name, ca | |
204 | in sorted(ca_list, key=lambda e: e[1].counter) |
|
204 | in sorted(ca_list, key=lambda e: e[1].counter) | |
205 | ]) |
|
205 | ]) | |
206 |
|
206 | |||
207 | had_default = False |
|
207 | had_default = False | |
208 | for a in cls.__attrs_attrs__: |
|
208 | for a in cls.__attrs_attrs__: | |
209 | if these is None and a not in super_cls: |
|
209 | if these is None and a not in super_cls: | |
210 | setattr(cls, a.name, a) |
|
210 | setattr(cls, a.name, a) | |
211 | if had_default is True and a.default is NOTHING and a.init is True: |
|
211 | if had_default is True and a.default is NOTHING and a.init is True: | |
212 | raise ValueError( |
|
212 | raise ValueError( | |
213 | "No mandatory attributes allowed after an attribute with a " |
|
213 | "No mandatory attributes allowed after an attribute with a " | |
214 | "default value or factory. Attribute in question: {a!r}" |
|
214 | "default value or factory. Attribute in question: {a!r}" | |
215 | .format(a=a) |
|
215 | .format(a=a) | |
216 | ) |
|
216 | ) | |
217 | elif had_default is False and \ |
|
217 | elif had_default is False and \ | |
218 | a.default is not NOTHING and \ |
|
218 | a.default is not NOTHING and \ | |
219 | a.init is not False: |
|
219 | a.init is not False: | |
220 | had_default = True |
|
220 | had_default = True | |
221 |
|
221 | |||
222 |
|
222 | |||
223 | def _frozen_setattrs(self, name, value): |
|
223 | def _frozen_setattrs(self, name, value): | |
224 | """ |
|
224 | """ | |
225 | Attached to frozen classes as __setattr__. |
|
225 | Attached to frozen classes as __setattr__. | |
226 | """ |
|
226 | """ | |
227 | raise FrozenInstanceError() |
|
227 | raise FrozenInstanceError() | |
228 |
|
228 | |||
229 |
|
229 | |||
230 | def _frozen_delattrs(self, name): |
|
230 | def _frozen_delattrs(self, name): | |
231 | """ |
|
231 | """ | |
232 | Attached to frozen classes as __delattr__. |
|
232 | Attached to frozen classes as __delattr__. | |
233 | """ |
|
233 | """ | |
234 | raise FrozenInstanceError() |
|
234 | raise FrozenInstanceError() | |
235 |
|
235 | |||
236 |
|
236 | |||
237 | def attributes(maybe_cls=None, these=None, repr_ns=None, |
|
237 | def attributes(maybe_cls=None, these=None, repr_ns=None, | |
238 | repr=True, cmp=True, hash=None, init=True, |
|
238 | repr=True, cmp=True, hash=None, init=True, | |
239 | slots=False, frozen=False, str=False): |
|
239 | slots=False, frozen=False, str=False): | |
240 | r""" |
|
240 | r""" | |
241 | A class decorator that adds `dunder |
|
241 | A class decorator that adds `dunder | |
242 | <https://wiki.python.org/moin/DunderAlias>`_\ -methods according to the |
|
242 | <https://wiki.python.org/moin/DunderAlias>`_\ -methods according to the | |
243 | specified attributes using :func:`attr.ib` or the *these* argument. |
|
243 | specified attributes using :func:`attr.ib` or the *these* argument. | |
244 |
|
244 | |||
245 | :param these: A dictionary of name to :func:`attr.ib` mappings. This is |
|
245 | :param these: A dictionary of name to :func:`attr.ib` mappings. This is | |
246 | useful to avoid the definition of your attributes within the class body |
|
246 | useful to avoid the definition of your attributes within the class body | |
247 | because you can't (e.g. if you want to add ``__repr__`` methods to |
|
247 | because you can't (e.g. if you want to add ``__repr__`` methods to | |
248 | Django models) or don't want to. |
|
248 | Django models) or don't want to. | |
249 |
|
249 | |||
250 | If *these* is not ``None``, ``attrs`` will *not* search the class body |
|
250 | If *these* is not ``None``, ``attrs`` will *not* search the class body | |
251 | for attributes. |
|
251 | for attributes. | |
252 |
|
252 | |||
253 | :type these: :class:`dict` of :class:`str` to :func:`attr.ib` |
|
253 | :type these: :class:`dict` of :class:`str` to :func:`attr.ib` | |
254 |
|
254 | |||
255 | :param str repr_ns: When using nested classes, there's no way in Python 2 |
|
255 | :param str repr_ns: When using nested classes, there's no way in Python 2 | |
256 | to automatically detect that. Therefore it's possible to set the |
|
256 | to automatically detect that. Therefore it's possible to set the | |
257 | namespace explicitly for a more meaningful ``repr`` output. |
|
257 | namespace explicitly for a more meaningful ``repr`` output. | |
258 | :param bool repr: Create a ``__repr__`` method with a human readable |
|
258 | :param bool repr: Create a ``__repr__`` method with a human readable | |
259 | represantation of ``attrs`` attributes.. |
|
259 | represantation of ``attrs`` attributes.. | |
260 | :param bool str: Create a ``__str__`` method that is identical to |
|
260 | :param bool str: Create a ``__str__`` method that is identical to | |
261 | ``__repr__``. This is usually not necessary except for |
|
261 | ``__repr__``. This is usually not necessary except for | |
262 | :class:`Exception`\ s. |
|
262 | :class:`Exception`\ s. | |
263 | :param bool cmp: Create ``__eq__``, ``__ne__``, ``__lt__``, ``__le__``, |
|
263 | :param bool cmp: Create ``__eq__``, ``__ne__``, ``__lt__``, ``__le__``, | |
264 | ``__gt__``, and ``__ge__`` methods that compare the class as if it were |
|
264 | ``__gt__``, and ``__ge__`` methods that compare the class as if it were | |
265 | a tuple of its ``attrs`` attributes. But the attributes are *only* |
|
265 | a tuple of its ``attrs`` attributes. But the attributes are *only* | |
266 | compared, if the type of both classes is *identical*! |
|
266 | compared, if the type of both classes is *identical*! | |
267 | :param hash: If ``None`` (default), the ``__hash__`` method is generated |
|
267 | :param hash: If ``None`` (default), the ``__hash__`` method is generated | |
268 | according how *cmp* and *frozen* are set. |
|
268 | according how *cmp* and *frozen* are set. | |
269 |
|
269 | |||
270 | 1. If *both* are True, ``attrs`` will generate a ``__hash__`` for you. |
|
270 | 1. If *both* are True, ``attrs`` will generate a ``__hash__`` for you. | |
271 | 2. If *cmp* is True and *frozen* is False, ``__hash__`` will be set to |
|
271 | 2. If *cmp* is True and *frozen* is False, ``__hash__`` will be set to | |
272 | None, marking it unhashable (which it is). |
|
272 | None, marking it unhashable (which it is). | |
273 | 3. If *cmp* is False, ``__hash__`` will be left untouched meaning the |
|
273 | 3. If *cmp* is False, ``__hash__`` will be left untouched meaning the | |
274 | ``__hash__`` method of the superclass will be used (if superclass is |
|
274 | ``__hash__`` method of the superclass will be used (if superclass is | |
275 | ``object``, this means it will fall back to id-based hashing.). |
|
275 | ``object``, this means it will fall back to id-based hashing.). | |
276 |
|
276 | |||
277 | Although not recommended, you can decide for yourself and force |
|
277 | Although not recommended, you can decide for yourself and force | |
278 | ``attrs`` to create one (e.g. if the class is immutable even though you |
|
278 | ``attrs`` to create one (e.g. if the class is immutable even though you | |
279 | didn't freeze it programmatically) by passing ``True`` or not. Both of |
|
279 | didn't freeze it programmatically) by passing ``True`` or not. Both of | |
280 | these cases are rather special and should be used carefully. |
|
280 | these cases are rather special and should be used carefully. | |
281 |
|
281 | |||
282 | See the `Python documentation \ |
|
282 | See the `Python documentation \ | |
283 | <https://docs.python.org/3/reference/datamodel.html#object.__hash__>`_ |
|
283 | <https://docs.python.org/3/reference/datamodel.html#object.__hash__>`_ | |
284 | and the `GitHub issue that led to the default behavior \ |
|
284 | and the `GitHub issue that led to the default behavior \ | |
285 | <https://github.com/python-attrs/attrs/issues/136>`_ for more details. |
|
285 | <https://github.com/python-attrs/attrs/issues/136>`_ for more details. | |
286 | :type hash: ``bool`` or ``None`` |
|
286 | :type hash: ``bool`` or ``None`` | |
287 | :param bool init: Create a ``__init__`` method that initialiazes the |
|
287 | :param bool init: Create a ``__init__`` method that initialiazes the | |
288 | ``attrs`` attributes. Leading underscores are stripped for the |
|
288 | ``attrs`` attributes. Leading underscores are stripped for the | |
289 | argument name. If a ``__attrs_post_init__`` method exists on the |
|
289 | argument name. If a ``__attrs_post_init__`` method exists on the | |
290 | class, it will be called after the class is fully initialized. |
|
290 | class, it will be called after the class is fully initialized. | |
291 | :param bool slots: Create a slots_-style class that's more |
|
291 | :param bool slots: Create a slots_-style class that's more | |
292 | memory-efficient. See :ref:`slots` for further ramifications. |
|
292 | memory-efficient. See :ref:`slots` for further ramifications. | |
293 | :param bool frozen: Make instances immutable after initialization. If |
|
293 | :param bool frozen: Make instances immutable after initialization. If | |
294 | someone attempts to modify a frozen instance, |
|
294 | someone attempts to modify a frozen instance, | |
295 | :exc:`attr.exceptions.FrozenInstanceError` is raised. |
|
295 | :exc:`attr.exceptions.FrozenInstanceError` is raised. | |
296 |
|
296 | |||
297 | Please note: |
|
297 | Please note: | |
298 |
|
298 | |||
299 | 1. This is achieved by installing a custom ``__setattr__`` method |
|
299 | 1. This is achieved by installing a custom ``__setattr__`` method | |
300 | on your class so you can't implement an own one. |
|
300 | on your class so you can't implement an own one. | |
301 |
|
301 | |||
302 | 2. True immutability is impossible in Python. |
|
302 | 2. True immutability is impossible in Python. | |
303 |
|
303 | |||
304 | 3. This *does* have a minor a runtime performance :ref:`impact |
|
304 | 3. This *does* have a minor a runtime performance :ref:`impact | |
305 | <how-frozen>` when initializing new instances. In other words: |
|
305 | <how-frozen>` when initializing new instances. In other words: | |
306 | ``__init__`` is slightly slower with ``frozen=True``. |
|
306 | ``__init__`` is slightly slower with ``frozen=True``. | |
307 |
|
307 | |||
308 | 4. If a class is frozen, you cannot modify ``self`` in |
|
308 | 4. If a class is frozen, you cannot modify ``self`` in | |
309 | ``__attrs_post_init__`` or a self-written ``__init__``. You can |
|
309 | ``__attrs_post_init__`` or a self-written ``__init__``. You can | |
310 | circumvent that limitation by using |
|
310 | circumvent that limitation by using | |
311 | ``object.__setattr__(self, "attribute_name", value)``. |
|
311 | ``object.__setattr__(self, "attribute_name", value)``. | |
312 |
|
312 | |||
313 | .. _slots: https://docs.python.org/3.5/reference/datamodel.html#slots |
|
313 | .. _slots: https://docs.python.org/3.5/reference/datamodel.html#slots | |
314 |
|
314 | |||
315 | .. versionadded:: 16.0.0 *slots* |
|
315 | .. versionadded:: 16.0.0 *slots* | |
316 | .. versionadded:: 16.1.0 *frozen* |
|
316 | .. versionadded:: 16.1.0 *frozen* | |
317 | .. versionadded:: 16.3.0 *str*, and support for ``__attrs_post_init__``. |
|
317 | .. versionadded:: 16.3.0 *str*, and support for ``__attrs_post_init__``. | |
318 | .. versionchanged:: |
|
318 | .. versionchanged:: | |
319 | 17.1.0 *hash* supports ``None`` as value which is also the default |
|
319 | 17.1.0 *hash* supports ``None`` as value which is also the default | |
320 | now. |
|
320 | now. | |
321 | """ |
|
321 | """ | |
322 | def wrap(cls): |
|
322 | def wrap(cls): | |
323 | if getattr(cls, "__class__", None) is None: |
|
323 | if getattr(cls, "__class__", None) is None: | |
324 | raise TypeError("attrs only works with new-style classes.") |
|
324 | raise TypeError("attrs only works with new-style classes.") | |
325 |
|
325 | |||
326 | if repr is False and str is True: |
|
326 | if repr is False and str is True: | |
327 | raise ValueError( |
|
327 | raise ValueError( | |
328 | "__str__ can only be generated if a __repr__ exists." |
|
328 | "__str__ can only be generated if a __repr__ exists." | |
329 | ) |
|
329 | ) | |
330 |
|
330 | |||
331 | if slots: |
|
331 | if slots: | |
332 | # Only need this later if we're using slots. |
|
332 | # Only need this later if we're using slots. | |
333 | if these is None: |
|
333 | if these is None: | |
334 | ca_list = [name |
|
334 | ca_list = [name | |
335 | for name, attr |
|
335 | for name, attr | |
336 | in cls.__dict__.items() |
|
336 | in cls.__dict__.items() | |
337 | if isinstance(attr, _CountingAttr)] |
|
337 | if isinstance(attr, _CountingAttr)] | |
338 | else: |
|
338 | else: | |
339 | ca_list = list(iterkeys(these)) |
|
339 | ca_list = list(iterkeys(these)) | |
340 | _transform_attrs(cls, these) |
|
340 | _transform_attrs(cls, these) | |
341 |
|
341 | |||
342 | # Can't just re-use frozen name because Python's scoping. :( |
|
342 | # Can't just re-use frozen name because Python's scoping. :( | |
343 | # Can't compare function objects because Python 2 is terrible. :( |
|
343 | # Can't compare function objects because Python 2 is terrible. :( | |
344 | effectively_frozen = _has_frozen_superclass(cls) or frozen |
|
344 | effectively_frozen = _has_frozen_superclass(cls) or frozen | |
345 | if repr is True: |
|
345 | if repr is True: | |
346 | cls = _add_repr(cls, ns=repr_ns) |
|
346 | cls = _add_repr(cls, ns=repr_ns) | |
347 | if str is True: |
|
347 | if str is True: | |
348 | cls.__str__ = cls.__repr__ |
|
348 | cls.__str__ = cls.__repr__ | |
349 | if cmp is True: |
|
349 | if cmp is True: | |
350 | cls = _add_cmp(cls) |
|
350 | cls = _add_cmp(cls) | |
351 |
|
351 | |||
352 | if hash is not True and hash is not False and hash is not None: |
|
352 | if hash is not True and hash is not False and hash is not None: | |
353 | raise TypeError( |
|
353 | raise TypeError( | |
354 | "Invalid value for hash. Must be True, False, or None." |
|
354 | "Invalid value for hash. Must be True, False, or None." | |
355 | ) |
|
355 | ) | |
356 | elif hash is False or (hash is None and cmp is False): |
|
356 | elif hash is False or (hash is None and cmp is False): | |
357 | pass |
|
357 | pass | |
358 | elif hash is True or (hash is None and cmp is True and frozen is True): |
|
358 | elif hash is True or (hash is None and cmp is True and frozen is True): | |
359 | cls = _add_hash(cls) |
|
359 | cls = _add_hash(cls) | |
360 | else: |
|
360 | else: | |
361 | cls.__hash__ = None |
|
361 | cls.__hash__ = None | |
362 |
|
362 | |||
363 | if init is True: |
|
363 | if init is True: | |
364 | cls = _add_init(cls, effectively_frozen) |
|
364 | cls = _add_init(cls, effectively_frozen) | |
365 | if effectively_frozen is True: |
|
365 | if effectively_frozen is True: | |
366 | cls.__setattr__ = _frozen_setattrs |
|
366 | cls.__setattr__ = _frozen_setattrs | |
367 | cls.__delattr__ = _frozen_delattrs |
|
367 | cls.__delattr__ = _frozen_delattrs | |
368 | if slots is True: |
|
368 | if slots is True: | |
369 | # slots and frozen require __getstate__/__setstate__ to work |
|
369 | # slots and frozen require __getstate__/__setstate__ to work | |
370 | cls = _add_pickle(cls) |
|
370 | cls = _add_pickle(cls) | |
371 | if slots is True: |
|
371 | if slots is True: | |
372 | cls_dict = dict(cls.__dict__) |
|
372 | cls_dict = dict(cls.__dict__) | |
373 | cls_dict["__slots__"] = tuple(ca_list) |
|
373 | cls_dict["__slots__"] = tuple(ca_list) | |
374 | for ca_name in ca_list: |
|
374 | for ca_name in ca_list: | |
375 | # It might not actually be in there, e.g. if using 'these'. |
|
375 | # It might not actually be in there, e.g. if using 'these'. | |
376 | cls_dict.pop(ca_name, None) |
|
376 | cls_dict.pop(ca_name, None) | |
377 | cls_dict.pop("__dict__", None) |
|
377 | cls_dict.pop("__dict__", None) | |
378 |
|
378 | |||
379 | qualname = getattr(cls, "__qualname__", None) |
|
379 | qualname = getattr(cls, "__qualname__", None) | |
380 | cls = type(cls)(cls.__name__, cls.__bases__, cls_dict) |
|
380 | cls = type(cls)(cls.__name__, cls.__bases__, cls_dict) | |
381 | if qualname is not None: |
|
381 | if qualname is not None: | |
382 | cls.__qualname__ = qualname |
|
382 | cls.__qualname__ = qualname | |
383 |
|
383 | |||
384 | return cls |
|
384 | return cls | |
385 |
|
385 | |||
386 | # attrs_or class type depends on the usage of the decorator. It's a class |
|
386 | # attrs_or class type depends on the usage of the decorator. It's a class | |
387 | # if it's used as `@attributes` but ``None`` if used # as `@attributes()`. |
|
387 | # if it's used as `@attributes` but ``None`` if used # as `@attributes()`. | |
388 | if maybe_cls is None: |
|
388 | if maybe_cls is None: | |
389 | return wrap |
|
389 | return wrap | |
390 | else: |
|
390 | else: | |
391 | return wrap(maybe_cls) |
|
391 | return wrap(maybe_cls) | |
392 |
|
392 | |||
393 |
|
393 | |||
394 | if PY2: |
|
394 | if PY2: | |
395 | def _has_frozen_superclass(cls): |
|
395 | def _has_frozen_superclass(cls): | |
396 | """ |
|
396 | """ | |
397 | Check whether *cls* has a frozen ancestor by looking at its |
|
397 | Check whether *cls* has a frozen ancestor by looking at its | |
398 | __setattr__. |
|
398 | __setattr__. | |
399 | """ |
|
399 | """ | |
400 | return ( |
|
400 | return ( | |
401 | getattr( |
|
401 | getattr( | |
402 | cls.__setattr__, "__module__", None |
|
402 | cls.__setattr__, "__module__", None | |
403 | ) == _frozen_setattrs.__module__ and |
|
403 | ) == _frozen_setattrs.__module__ and | |
404 | cls.__setattr__.__name__ == _frozen_setattrs.__name__ |
|
404 | cls.__setattr__.__name__ == _frozen_setattrs.__name__ | |
405 | ) |
|
405 | ) | |
406 | else: |
|
406 | else: | |
407 | def _has_frozen_superclass(cls): |
|
407 | def _has_frozen_superclass(cls): | |
408 | """ |
|
408 | """ | |
409 | Check whether *cls* has a frozen ancestor by looking at its |
|
409 | Check whether *cls* has a frozen ancestor by looking at its | |
410 | __setattr__. |
|
410 | __setattr__. | |
411 | """ |
|
411 | """ | |
412 | return cls.__setattr__ == _frozen_setattrs |
|
412 | return cls.__setattr__ == _frozen_setattrs | |
413 |
|
413 | |||
414 |
|
414 | |||
415 | def _attrs_to_tuple(obj, attrs): |
|
415 | def _attrs_to_tuple(obj, attrs): | |
416 | """ |
|
416 | """ | |
417 | Create a tuple of all values of *obj*'s *attrs*. |
|
417 | Create a tuple of all values of *obj*'s *attrs*. | |
418 | """ |
|
418 | """ | |
419 | return tuple(getattr(obj, a.name) for a in attrs) |
|
419 | return tuple(getattr(obj, a.name) for a in attrs) | |
420 |
|
420 | |||
421 |
|
421 | |||
422 | def _add_hash(cls, attrs=None): |
|
422 | def _add_hash(cls, attrs=None): | |
423 | """ |
|
423 | """ | |
424 | Add a hash method to *cls*. |
|
424 | Add a hash method to *cls*. | |
425 | """ |
|
425 | """ | |
426 | if attrs is None: |
|
426 | if attrs is None: | |
427 | attrs = [a |
|
427 | attrs = [a | |
428 | for a in cls.__attrs_attrs__ |
|
428 | for a in cls.__attrs_attrs__ | |
429 | if a.hash is True or (a.hash is None and a.cmp is True)] |
|
429 | if a.hash is True or (a.hash is None and a.cmp is True)] | |
430 |
|
430 | |||
431 | def hash_(self): |
|
431 | def hash_(self): | |
432 | """ |
|
432 | """ | |
433 | Automatically created by attrs. |
|
433 | Automatically created by attrs. | |
434 | """ |
|
434 | """ | |
435 | return hash(_attrs_to_tuple(self, attrs)) |
|
435 | return hash(_attrs_to_tuple(self, attrs)) | |
436 |
|
436 | |||
437 | cls.__hash__ = hash_ |
|
437 | cls.__hash__ = hash_ | |
438 | return cls |
|
438 | return cls | |
439 |
|
439 | |||
440 |
|
440 | |||
441 | def _add_cmp(cls, attrs=None): |
|
441 | def _add_cmp(cls, attrs=None): | |
442 | """ |
|
442 | """ | |
443 | Add comparison methods to *cls*. |
|
443 | Add comparison methods to *cls*. | |
444 | """ |
|
444 | """ | |
445 | if attrs is None: |
|
445 | if attrs is None: | |
446 | attrs = [a for a in cls.__attrs_attrs__ if a.cmp] |
|
446 | attrs = [a for a in cls.__attrs_attrs__ if a.cmp] | |
447 |
|
447 | |||
448 | def attrs_to_tuple(obj): |
|
448 | def attrs_to_tuple(obj): | |
449 | """ |
|
449 | """ | |
450 | Save us some typing. |
|
450 | Save us some typing. | |
451 | """ |
|
451 | """ | |
452 | return _attrs_to_tuple(obj, attrs) |
|
452 | return _attrs_to_tuple(obj, attrs) | |
453 |
|
453 | |||
454 | def eq(self, other): |
|
454 | def eq(self, other): | |
455 | """ |
|
455 | """ | |
456 | Automatically created by attrs. |
|
456 | Automatically created by attrs. | |
457 | """ |
|
457 | """ | |
458 | if other.__class__ is self.__class__: |
|
458 | if other.__class__ is self.__class__: | |
459 | return attrs_to_tuple(self) == attrs_to_tuple(other) |
|
459 | return attrs_to_tuple(self) == attrs_to_tuple(other) | |
460 | else: |
|
460 | else: | |
461 | return NotImplemented |
|
461 | return NotImplemented | |
462 |
|
462 | |||
463 | def ne(self, other): |
|
463 | def ne(self, other): | |
464 | """ |
|
464 | """ | |
465 | Automatically created by attrs. |
|
465 | Automatically created by attrs. | |
466 | """ |
|
466 | """ | |
467 | result = eq(self, other) |
|
467 | result = eq(self, other) | |
468 | if result is NotImplemented: |
|
468 | if result is NotImplemented: | |
469 | return NotImplemented |
|
469 | return NotImplemented | |
470 | else: |
|
470 | else: | |
471 | return not result |
|
471 | return not result | |
472 |
|
472 | |||
473 | def lt(self, other): |
|
473 | def lt(self, other): | |
474 | """ |
|
474 | """ | |
475 | Automatically created by attrs. |
|
475 | Automatically created by attrs. | |
476 | """ |
|
476 | """ | |
477 | if isinstance(other, self.__class__): |
|
477 | if isinstance(other, self.__class__): | |
478 | return attrs_to_tuple(self) < attrs_to_tuple(other) |
|
478 | return attrs_to_tuple(self) < attrs_to_tuple(other) | |
479 | else: |
|
479 | else: | |
480 | return NotImplemented |
|
480 | return NotImplemented | |
481 |
|
481 | |||
482 | def le(self, other): |
|
482 | def le(self, other): | |
483 | """ |
|
483 | """ | |
484 | Automatically created by attrs. |
|
484 | Automatically created by attrs. | |
485 | """ |
|
485 | """ | |
486 | if isinstance(other, self.__class__): |
|
486 | if isinstance(other, self.__class__): | |
487 | return attrs_to_tuple(self) <= attrs_to_tuple(other) |
|
487 | return attrs_to_tuple(self) <= attrs_to_tuple(other) | |
488 | else: |
|
488 | else: | |
489 | return NotImplemented |
|
489 | return NotImplemented | |
490 |
|
490 | |||
491 | def gt(self, other): |
|
491 | def gt(self, other): | |
492 | """ |
|
492 | """ | |
493 | Automatically created by attrs. |
|
493 | Automatically created by attrs. | |
494 | """ |
|
494 | """ | |
495 | if isinstance(other, self.__class__): |
|
495 | if isinstance(other, self.__class__): | |
496 | return attrs_to_tuple(self) > attrs_to_tuple(other) |
|
496 | return attrs_to_tuple(self) > attrs_to_tuple(other) | |
497 | else: |
|
497 | else: | |
498 | return NotImplemented |
|
498 | return NotImplemented | |
499 |
|
499 | |||
500 | def ge(self, other): |
|
500 | def ge(self, other): | |
501 | """ |
|
501 | """ | |
502 | Automatically created by attrs. |
|
502 | Automatically created by attrs. | |
503 | """ |
|
503 | """ | |
504 | if isinstance(other, self.__class__): |
|
504 | if isinstance(other, self.__class__): | |
505 | return attrs_to_tuple(self) >= attrs_to_tuple(other) |
|
505 | return attrs_to_tuple(self) >= attrs_to_tuple(other) | |
506 | else: |
|
506 | else: | |
507 | return NotImplemented |
|
507 | return NotImplemented | |
508 |
|
508 | |||
509 | cls.__eq__ = eq |
|
509 | cls.__eq__ = eq | |
510 | cls.__ne__ = ne |
|
510 | cls.__ne__ = ne | |
511 | cls.__lt__ = lt |
|
511 | cls.__lt__ = lt | |
512 | cls.__le__ = le |
|
512 | cls.__le__ = le | |
513 | cls.__gt__ = gt |
|
513 | cls.__gt__ = gt | |
514 | cls.__ge__ = ge |
|
514 | cls.__ge__ = ge | |
515 |
|
515 | |||
516 | return cls |
|
516 | return cls | |
517 |
|
517 | |||
518 |
|
518 | |||
519 | def _add_repr(cls, ns=None, attrs=None): |
|
519 | def _add_repr(cls, ns=None, attrs=None): | |
520 | """ |
|
520 | """ | |
521 | Add a repr method to *cls*. |
|
521 | Add a repr method to *cls*. | |
522 | """ |
|
522 | """ | |
523 | if attrs is None: |
|
523 | if attrs is None: | |
524 | attrs = [a for a in cls.__attrs_attrs__ if a.repr] |
|
524 | attrs = [a for a in cls.__attrs_attrs__ if a.repr] | |
525 |
|
525 | |||
526 | def repr_(self): |
|
526 | def repr_(self): | |
527 | """ |
|
527 | """ | |
528 | Automatically created by attrs. |
|
528 | Automatically created by attrs. | |
529 | """ |
|
529 | """ | |
530 | real_cls = self.__class__ |
|
530 | real_cls = self.__class__ | |
531 | if ns is None: |
|
531 | if ns is None: | |
532 | qualname = getattr(real_cls, "__qualname__", None) |
|
532 | qualname = getattr(real_cls, "__qualname__", None) | |
533 | if qualname is not None: |
|
533 | if qualname is not None: | |
534 | class_name = qualname.rsplit(">.", 1)[-1] |
|
534 | class_name = qualname.rsplit(">.", 1)[-1] | |
535 | else: |
|
535 | else: | |
536 | class_name = real_cls.__name__ |
|
536 | class_name = real_cls.__name__ | |
537 | else: |
|
537 | else: | |
538 | class_name = ns + "." + real_cls.__name__ |
|
538 | class_name = ns + "." + real_cls.__name__ | |
539 |
|
539 | |||
540 | return "{0}({1})".format( |
|
540 | return "{0}({1})".format( | |
541 | class_name, |
|
541 | class_name, | |
542 | ", ".join(a.name + "=" + repr(getattr(self, a.name)) |
|
542 | ", ".join(a.name + "=" + repr(getattr(self, a.name)) | |
543 | for a in attrs) |
|
543 | for a in attrs) | |
544 | ) |
|
544 | ) | |
545 | cls.__repr__ = repr_ |
|
545 | cls.__repr__ = repr_ | |
546 | return cls |
|
546 | return cls | |
547 |
|
547 | |||
548 |
|
548 | |||
549 | def _add_init(cls, frozen): |
|
549 | def _add_init(cls, frozen): | |
550 | """ |
|
550 | """ | |
551 | Add a __init__ method to *cls*. If *frozen* is True, make it immutable. |
|
551 | Add a __init__ method to *cls*. If *frozen* is True, make it immutable. | |
552 | """ |
|
552 | """ | |
553 | attrs = [a for a in cls.__attrs_attrs__ |
|
553 | attrs = [a for a in cls.__attrs_attrs__ | |
554 | if a.init or a.default is not NOTHING] |
|
554 | if a.init or a.default is not NOTHING] | |
555 |
|
555 | |||
556 | # We cache the generated init methods for the same kinds of attributes. |
|
556 | # We cache the generated init methods for the same kinds of attributes. | |
557 | sha1 = hashlib.sha1() |
|
557 | sha1 = hashlib.sha1() | |
558 | sha1.update(repr(attrs).encode("utf-8")) |
|
558 | sha1.update(repr(attrs).encode("utf-8")) | |
559 | unique_filename = "<attrs generated init {0}>".format( |
|
559 | unique_filename = "<attrs generated init {0}>".format( | |
560 | sha1.hexdigest() |
|
560 | sha1.hexdigest() | |
561 | ) |
|
561 | ) | |
562 |
|
562 | |||
563 | script, globs = _attrs_to_script( |
|
563 | script, globs = _attrs_to_script( | |
564 | attrs, |
|
564 | attrs, | |
565 | frozen, |
|
565 | frozen, | |
566 | getattr(cls, "__attrs_post_init__", False), |
|
566 | getattr(cls, "__attrs_post_init__", False), | |
567 | ) |
|
567 | ) | |
568 | locs = {} |
|
568 | locs = {} | |
569 | bytecode = compile(script, unique_filename, "exec") |
|
569 | bytecode = compile(script, unique_filename, "exec") | |
570 | attr_dict = dict((a.name, a) for a in attrs) |
|
570 | attr_dict = dict((a.name, a) for a in attrs) | |
571 | globs.update({ |
|
571 | globs.update({ | |
572 | "NOTHING": NOTHING, |
|
572 | "NOTHING": NOTHING, | |
573 | "attr_dict": attr_dict, |
|
573 | "attr_dict": attr_dict, | |
574 | }) |
|
574 | }) | |
575 | if frozen is True: |
|
575 | if frozen is True: | |
576 | # Save the lookup overhead in __init__ if we need to circumvent |
|
576 | # Save the lookup overhead in __init__ if we need to circumvent | |
577 | # immutability. |
|
577 | # immutability. | |
578 | globs["_cached_setattr"] = _obj_setattr |
|
578 | globs["_cached_setattr"] = _obj_setattr | |
579 | eval(bytecode, globs, locs) |
|
579 | eval(bytecode, globs, locs) | |
580 | init = locs["__init__"] |
|
580 | init = locs["__init__"] | |
581 |
|
581 | |||
582 | # In order of debuggers like PDB being able to step through the code, |
|
582 | # In order of debuggers like PDB being able to step through the code, | |
583 | # we add a fake linecache entry. |
|
583 | # we add a fake linecache entry. | |
584 | linecache.cache[unique_filename] = ( |
|
584 | linecache.cache[unique_filename] = ( | |
585 | len(script), |
|
585 | len(script), | |
586 | None, |
|
586 | None, | |
587 | script.splitlines(True), |
|
587 | script.splitlines(True), | |
588 | unique_filename |
|
588 | unique_filename | |
589 | ) |
|
589 | ) | |
590 | cls.__init__ = init |
|
590 | cls.__init__ = init | |
591 | return cls |
|
591 | return cls | |
592 |
|
592 | |||
593 |
|
593 | |||
594 | def _add_pickle(cls): |
|
594 | def _add_pickle(cls): | |
595 | """ |
|
595 | """ | |
596 | Add pickle helpers, needed for frozen and slotted classes |
|
596 | Add pickle helpers, needed for frozen and slotted classes | |
597 | """ |
|
597 | """ | |
598 | def _slots_getstate__(obj): |
|
598 | def _slots_getstate__(obj): | |
599 | """ |
|
599 | """ | |
600 | Play nice with pickle. |
|
600 | Play nice with pickle. | |
601 | """ |
|
601 | """ | |
602 | return tuple(getattr(obj, a.name) for a in fields(obj.__class__)) |
|
602 | return tuple(getattr(obj, a.name) for a in fields(obj.__class__)) | |
603 |
|
603 | |||
604 | def _slots_setstate__(obj, state): |
|
604 | def _slots_setstate__(obj, state): | |
605 | """ |
|
605 | """ | |
606 | Play nice with pickle. |
|
606 | Play nice with pickle. | |
607 | """ |
|
607 | """ | |
608 | __bound_setattr = _obj_setattr.__get__(obj, Attribute) |
|
608 | __bound_setattr = _obj_setattr.__get__(obj, Attribute) | |
609 | for a, value in zip(fields(obj.__class__), state): |
|
609 | for a, value in zip(fields(obj.__class__), state): | |
610 | __bound_setattr(a.name, value) |
|
610 | __bound_setattr(a.name, value) | |
611 |
|
611 | |||
612 | cls.__getstate__ = _slots_getstate__ |
|
612 | cls.__getstate__ = _slots_getstate__ | |
613 | cls.__setstate__ = _slots_setstate__ |
|
613 | cls.__setstate__ = _slots_setstate__ | |
614 | return cls |
|
614 | return cls | |
615 |
|
615 | |||
616 |
|
616 | |||
617 | def fields(cls): |
|
617 | def fields(cls): | |
618 | """ |
|
618 | """ | |
619 | Returns the tuple of ``attrs`` attributes for a class. |
|
619 | Returns the tuple of ``attrs`` attributes for a class. | |
620 |
|
620 | |||
621 | The tuple also allows accessing the fields by their names (see below for |
|
621 | The tuple also allows accessing the fields by their names (see below for | |
622 | examples). |
|
622 | examples). | |
623 |
|
623 | |||
624 | :param type cls: Class to introspect. |
|
624 | :param type cls: Class to introspect. | |
625 |
|
625 | |||
626 | :raise TypeError: If *cls* is not a class. |
|
626 | :raise TypeError: If *cls* is not a class. | |
627 | :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs`` |
|
627 | :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs`` | |
628 | class. |
|
628 | class. | |
629 |
|
629 | |||
630 | :rtype: tuple (with name accesors) of :class:`attr.Attribute` |
|
630 | :rtype: tuple (with name accesors) of :class:`attr.Attribute` | |
631 |
|
631 | |||
632 | .. versionchanged:: 16.2.0 Returned tuple allows accessing the fields |
|
632 | .. versionchanged:: 16.2.0 Returned tuple allows accessing the fields | |
633 | by name. |
|
633 | by name. | |
634 | """ |
|
634 | """ | |
635 | if not isclass(cls): |
|
635 | if not isclass(cls): | |
636 | raise TypeError("Passed object must be a class.") |
|
636 | raise TypeError("Passed object must be a class.") | |
637 | attrs = getattr(cls, "__attrs_attrs__", None) |
|
637 | attrs = getattr(cls, "__attrs_attrs__", None) | |
638 | if attrs is None: |
|
638 | if attrs is None: | |
639 | raise NotAnAttrsClassError( |
|
639 | raise NotAnAttrsClassError( | |
640 | "{cls!r} is not an attrs-decorated class.".format(cls=cls) |
|
640 | "{cls!r} is not an attrs-decorated class.".format(cls=cls) | |
641 | ) |
|
641 | ) | |
642 | return attrs |
|
642 | return attrs | |
643 |
|
643 | |||
644 |
|
644 | |||
645 | def validate(inst): |
|
645 | def validate(inst): | |
646 | """ |
|
646 | """ | |
647 | Validate all attributes on *inst* that have a validator. |
|
647 | Validate all attributes on *inst* that have a validator. | |
648 |
|
648 | |||
649 | Leaves all exceptions through. |
|
649 | Leaves all exceptions through. | |
650 |
|
650 | |||
651 | :param inst: Instance of a class with ``attrs`` attributes. |
|
651 | :param inst: Instance of a class with ``attrs`` attributes. | |
652 | """ |
|
652 | """ | |
653 | if _config._run_validators is False: |
|
653 | if _config._run_validators is False: | |
654 | return |
|
654 | return | |
655 |
|
655 | |||
656 | for a in fields(inst.__class__): |
|
656 | for a in fields(inst.__class__): | |
657 | v = a.validator |
|
657 | v = a.validator | |
658 | if v is not None: |
|
658 | if v is not None: | |
659 | v(inst, a, getattr(inst, a.name)) |
|
659 | v(inst, a, getattr(inst, a.name)) | |
660 |
|
660 | |||
661 |
|
661 | |||
662 | def _attrs_to_script(attrs, frozen, post_init): |
|
662 | def _attrs_to_script(attrs, frozen, post_init): | |
663 | """ |
|
663 | """ | |
664 | Return a script of an initializer for *attrs* and a dict of globals. |
|
664 | Return a script of an initializer for *attrs* and a dict of globals. | |
665 |
|
665 | |||
666 | The globals are expected by the generated script. |
|
666 | The globals are expected by the generated script. | |
667 |
|
667 | |||
668 | If *frozen* is True, we cannot set the attributes directly so we use |
|
668 | If *frozen* is True, we cannot set the attributes directly so we use | |
669 | a cached ``object.__setattr__``. |
|
669 | a cached ``object.__setattr__``. | |
670 | """ |
|
670 | """ | |
671 | lines = [] |
|
671 | lines = [] | |
672 | if frozen is True: |
|
672 | if frozen is True: | |
673 | lines.append( |
|
673 | lines.append( | |
674 | # Circumvent the __setattr__ descriptor to save one lookup per |
|
674 | # Circumvent the __setattr__ descriptor to save one lookup per | |
675 | # assignment. |
|
675 | # assignment. | |
676 | "_setattr = _cached_setattr.__get__(self, self.__class__)" |
|
676 | "_setattr = _cached_setattr.__get__(self, self.__class__)" | |
677 | ) |
|
677 | ) | |
678 |
|
678 | |||
679 | def fmt_setter(attr_name, value_var): |
|
679 | def fmt_setter(attr_name, value_var): | |
680 | return "_setattr('%(attr_name)s', %(value_var)s)" % { |
|
680 | return "_setattr('%(attr_name)s', %(value_var)s)" % { | |
681 | "attr_name": attr_name, |
|
681 | "attr_name": attr_name, | |
682 | "value_var": value_var, |
|
682 | "value_var": value_var, | |
683 | } |
|
683 | } | |
684 |
|
684 | |||
685 | def fmt_setter_with_converter(attr_name, value_var): |
|
685 | def fmt_setter_with_converter(attr_name, value_var): | |
686 | conv_name = _init_convert_pat.format(attr_name) |
|
686 | conv_name = _init_convert_pat.format(attr_name) | |
687 | return "_setattr('%(attr_name)s', %(conv)s(%(value_var)s))" % { |
|
687 | return "_setattr('%(attr_name)s', %(conv)s(%(value_var)s))" % { | |
688 | "attr_name": attr_name, |
|
688 | "attr_name": attr_name, | |
689 | "value_var": value_var, |
|
689 | "value_var": value_var, | |
690 | "conv": conv_name, |
|
690 | "conv": conv_name, | |
691 | } |
|
691 | } | |
692 | else: |
|
692 | else: | |
693 | def fmt_setter(attr_name, value): |
|
693 | def fmt_setter(attr_name, value): | |
694 | return "self.%(attr_name)s = %(value)s" % { |
|
694 | return "self.%(attr_name)s = %(value)s" % { | |
695 | "attr_name": attr_name, |
|
695 | "attr_name": attr_name, | |
696 | "value": value, |
|
696 | "value": value, | |
697 | } |
|
697 | } | |
698 |
|
698 | |||
699 | def fmt_setter_with_converter(attr_name, value_var): |
|
699 | def fmt_setter_with_converter(attr_name, value_var): | |
700 | conv_name = _init_convert_pat.format(attr_name) |
|
700 | conv_name = _init_convert_pat.format(attr_name) | |
701 | return "self.%(attr_name)s = %(conv)s(%(value_var)s)" % { |
|
701 | return "self.%(attr_name)s = %(conv)s(%(value_var)s)" % { | |
702 | "attr_name": attr_name, |
|
702 | "attr_name": attr_name, | |
703 | "value_var": value_var, |
|
703 | "value_var": value_var, | |
704 | "conv": conv_name, |
|
704 | "conv": conv_name, | |
705 | } |
|
705 | } | |
706 |
|
706 | |||
707 | args = [] |
|
707 | args = [] | |
708 | attrs_to_validate = [] |
|
708 | attrs_to_validate = [] | |
709 |
|
709 | |||
710 | # This is a dictionary of names to validator and converter callables. |
|
710 | # This is a dictionary of names to validator and converter callables. | |
711 | # Injecting this into __init__ globals lets us avoid lookups. |
|
711 | # Injecting this into __init__ globals lets us avoid lookups. | |
712 | names_for_globals = {} |
|
712 | names_for_globals = {} | |
713 |
|
713 | |||
714 | for a in attrs: |
|
714 | for a in attrs: | |
715 | if a.validator: |
|
715 | if a.validator: | |
716 | attrs_to_validate.append(a) |
|
716 | attrs_to_validate.append(a) | |
717 | attr_name = a.name |
|
717 | attr_name = a.name | |
718 | arg_name = a.name.lstrip("_") |
|
718 | arg_name = a.name.lstrip("_") | |
719 | has_factory = isinstance(a.default, Factory) |
|
719 | has_factory = isinstance(a.default, Factory) | |
720 | if has_factory and a.default.takes_self: |
|
720 | if has_factory and a.default.takes_self: | |
721 | maybe_self = "self" |
|
721 | maybe_self = "self" | |
722 | else: |
|
722 | else: | |
723 | maybe_self = "" |
|
723 | maybe_self = "" | |
724 | if a.init is False: |
|
724 | if a.init is False: | |
725 | if has_factory: |
|
725 | if has_factory: | |
726 | init_factory_name = _init_factory_pat.format(a.name) |
|
726 | init_factory_name = _init_factory_pat.format(a.name) | |
727 | if a.convert is not None: |
|
727 | if a.convert is not None: | |
728 | lines.append(fmt_setter_with_converter( |
|
728 | lines.append(fmt_setter_with_converter( | |
729 | attr_name, |
|
729 | attr_name, | |
730 | init_factory_name + "({0})".format(maybe_self))) |
|
730 | init_factory_name + "({0})".format(maybe_self))) | |
731 | conv_name = _init_convert_pat.format(a.name) |
|
731 | conv_name = _init_convert_pat.format(a.name) | |
732 | names_for_globals[conv_name] = a.convert |
|
732 | names_for_globals[conv_name] = a.convert | |
733 | else: |
|
733 | else: | |
734 | lines.append(fmt_setter( |
|
734 | lines.append(fmt_setter( | |
735 | attr_name, |
|
735 | attr_name, | |
736 | init_factory_name + "({0})".format(maybe_self) |
|
736 | init_factory_name + "({0})".format(maybe_self) | |
737 | )) |
|
737 | )) | |
738 | names_for_globals[init_factory_name] = a.default.factory |
|
738 | names_for_globals[init_factory_name] = a.default.factory | |
739 | else: |
|
739 | else: | |
740 | if a.convert is not None: |
|
740 | if a.convert is not None: | |
741 | lines.append(fmt_setter_with_converter( |
|
741 | lines.append(fmt_setter_with_converter( | |
742 | attr_name, |
|
742 | attr_name, | |
743 | "attr_dict['{attr_name}'].default" |
|
743 | "attr_dict['{attr_name}'].default" | |
744 | .format(attr_name=attr_name) |
|
744 | .format(attr_name=attr_name) | |
745 | )) |
|
745 | )) | |
746 | conv_name = _init_convert_pat.format(a.name) |
|
746 | conv_name = _init_convert_pat.format(a.name) | |
747 | names_for_globals[conv_name] = a.convert |
|
747 | names_for_globals[conv_name] = a.convert | |
748 | else: |
|
748 | else: | |
749 | lines.append(fmt_setter( |
|
749 | lines.append(fmt_setter( | |
750 | attr_name, |
|
750 | attr_name, | |
751 | "attr_dict['{attr_name}'].default" |
|
751 | "attr_dict['{attr_name}'].default" | |
752 | .format(attr_name=attr_name) |
|
752 | .format(attr_name=attr_name) | |
753 | )) |
|
753 | )) | |
754 | elif a.default is not NOTHING and not has_factory: |
|
754 | elif a.default is not NOTHING and not has_factory: | |
755 | args.append( |
|
755 | args.append( | |
756 | "{arg_name}=attr_dict['{attr_name}'].default".format( |
|
756 | "{arg_name}=attr_dict['{attr_name}'].default".format( | |
757 | arg_name=arg_name, |
|
757 | arg_name=arg_name, | |
758 | attr_name=attr_name, |
|
758 | attr_name=attr_name, | |
759 | ) |
|
759 | ) | |
760 | ) |
|
760 | ) | |
761 | if a.convert is not None: |
|
761 | if a.convert is not None: | |
762 | lines.append(fmt_setter_with_converter(attr_name, arg_name)) |
|
762 | lines.append(fmt_setter_with_converter(attr_name, arg_name)) | |
763 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert |
|
763 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert | |
764 | else: |
|
764 | else: | |
765 | lines.append(fmt_setter(attr_name, arg_name)) |
|
765 | lines.append(fmt_setter(attr_name, arg_name)) | |
766 | elif has_factory: |
|
766 | elif has_factory: | |
767 | args.append("{arg_name}=NOTHING".format(arg_name=arg_name)) |
|
767 | args.append("{arg_name}=NOTHING".format(arg_name=arg_name)) | |
768 | lines.append("if {arg_name} is not NOTHING:" |
|
768 | lines.append("if {arg_name} is not NOTHING:" | |
769 | .format(arg_name=arg_name)) |
|
769 | .format(arg_name=arg_name)) | |
770 | init_factory_name = _init_factory_pat.format(a.name) |
|
770 | init_factory_name = _init_factory_pat.format(a.name) | |
771 | if a.convert is not None: |
|
771 | if a.convert is not None: | |
772 | lines.append(" " + fmt_setter_with_converter(attr_name, |
|
772 | lines.append(" " + fmt_setter_with_converter(attr_name, | |
773 | arg_name)) |
|
773 | arg_name)) | |
774 | lines.append("else:") |
|
774 | lines.append("else:") | |
775 | lines.append(" " + fmt_setter_with_converter( |
|
775 | lines.append(" " + fmt_setter_with_converter( | |
776 | attr_name, |
|
776 | attr_name, | |
777 | init_factory_name + "({0})".format(maybe_self) |
|
777 | init_factory_name + "({0})".format(maybe_self) | |
778 | )) |
|
778 | )) | |
779 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert |
|
779 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert | |
780 | else: |
|
780 | else: | |
781 | lines.append(" " + fmt_setter(attr_name, arg_name)) |
|
781 | lines.append(" " + fmt_setter(attr_name, arg_name)) | |
782 | lines.append("else:") |
|
782 | lines.append("else:") | |
783 | lines.append(" " + fmt_setter( |
|
783 | lines.append(" " + fmt_setter( | |
784 | attr_name, |
|
784 | attr_name, | |
785 | init_factory_name + "({0})".format(maybe_self) |
|
785 | init_factory_name + "({0})".format(maybe_self) | |
786 | )) |
|
786 | )) | |
787 | names_for_globals[init_factory_name] = a.default.factory |
|
787 | names_for_globals[init_factory_name] = a.default.factory | |
788 | else: |
|
788 | else: | |
789 | args.append(arg_name) |
|
789 | args.append(arg_name) | |
790 | if a.convert is not None: |
|
790 | if a.convert is not None: | |
791 | lines.append(fmt_setter_with_converter(attr_name, arg_name)) |
|
791 | lines.append(fmt_setter_with_converter(attr_name, arg_name)) | |
792 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert |
|
792 | names_for_globals[_init_convert_pat.format(a.name)] = a.convert | |
793 | else: |
|
793 | else: | |
794 | lines.append(fmt_setter(attr_name, arg_name)) |
|
794 | lines.append(fmt_setter(attr_name, arg_name)) | |
795 |
|
795 | |||
796 | if attrs_to_validate: # we can skip this if there are no validators. |
|
796 | if attrs_to_validate: # we can skip this if there are no validators. | |
797 | names_for_globals["_config"] = _config |
|
797 | names_for_globals["_config"] = _config | |
798 | lines.append("if _config._run_validators is True:") |
|
798 | lines.append("if _config._run_validators is True:") | |
799 | for a in attrs_to_validate: |
|
799 | for a in attrs_to_validate: | |
800 | val_name = "__attr_validator_{}".format(a.name) |
|
800 | val_name = "__attr_validator_{}".format(a.name) | |
801 | attr_name = "__attr_{}".format(a.name) |
|
801 | attr_name = "__attr_{}".format(a.name) | |
802 | lines.append(" {}(self, {}, self.{})".format( |
|
802 | lines.append(" {}(self, {}, self.{})".format( | |
803 | val_name, attr_name, a.name)) |
|
803 | val_name, attr_name, a.name)) | |
804 | names_for_globals[val_name] = a.validator |
|
804 | names_for_globals[val_name] = a.validator | |
805 | names_for_globals[attr_name] = a |
|
805 | names_for_globals[attr_name] = a | |
806 | if post_init: |
|
806 | if post_init: | |
807 | lines.append("self.__attrs_post_init__()") |
|
807 | lines.append("self.__attrs_post_init__()") | |
808 |
|
808 | |||
809 | return """\ |
|
809 | return """\ | |
810 | def __init__(self, {args}): |
|
810 | def __init__(self, {args}): | |
811 | {lines} |
|
811 | {lines} | |
812 | """.format( |
|
812 | """.format( | |
813 | args=", ".join(args), |
|
813 | args=", ".join(args), | |
814 | lines="\n ".join(lines) if lines else "pass", |
|
814 | lines="\n ".join(lines) if lines else "pass", | |
815 | ), names_for_globals |
|
815 | ), names_for_globals | |
816 |
|
816 | |||
817 |
|
817 | |||
818 | class Attribute(object): |
|
818 | class Attribute(object): | |
819 | """ |
|
819 | """ | |
820 | *Read-only* representation of an attribute. |
|
820 | *Read-only* representation of an attribute. | |
821 |
|
821 | |||
822 | :attribute name: The name of the attribute. |
|
822 | :attribute name: The name of the attribute. | |
823 |
|
823 | |||
824 | Plus *all* arguments of :func:`attr.ib`. |
|
824 | Plus *all* arguments of :func:`attr.ib`. | |
825 | """ |
|
825 | """ | |
826 | __slots__ = ( |
|
826 | __slots__ = ( | |
827 | "name", "default", "validator", "repr", "cmp", "hash", "init", |
|
827 | "name", "default", "validator", "repr", "cmp", "hash", "init", | |
828 | "convert", "metadata", |
|
828 | "convert", "metadata", | |
829 | ) |
|
829 | ) | |
830 |
|
830 | |||
831 | def __init__(self, name, default, validator, repr, cmp, hash, init, |
|
831 | def __init__(self, name, default, validator, repr, cmp, hash, init, | |
832 | convert=None, metadata=None): |
|
832 | convert=None, metadata=None): | |
833 | # Cache this descriptor here to speed things up later. |
|
833 | # Cache this descriptor here to speed things up later. | |
834 | bound_setattr = _obj_setattr.__get__(self, Attribute) |
|
834 | bound_setattr = _obj_setattr.__get__(self, Attribute) | |
835 |
|
835 | |||
836 | bound_setattr("name", name) |
|
836 | bound_setattr("name", name) | |
837 | bound_setattr("default", default) |
|
837 | bound_setattr("default", default) | |
838 | bound_setattr("validator", validator) |
|
838 | bound_setattr("validator", validator) | |
839 | bound_setattr("repr", repr) |
|
839 | bound_setattr("repr", repr) | |
840 | bound_setattr("cmp", cmp) |
|
840 | bound_setattr("cmp", cmp) | |
841 | bound_setattr("hash", hash) |
|
841 | bound_setattr("hash", hash) | |
842 | bound_setattr("init", init) |
|
842 | bound_setattr("init", init) | |
843 | bound_setattr("convert", convert) |
|
843 | bound_setattr("convert", convert) | |
844 | bound_setattr("metadata", (metadata_proxy(metadata) if metadata |
|
844 | bound_setattr("metadata", (metadata_proxy(metadata) if metadata | |
845 | else _empty_metadata_singleton)) |
|
845 | else _empty_metadata_singleton)) | |
846 |
|
846 | |||
847 | def __setattr__(self, name, value): |
|
847 | def __setattr__(self, name, value): | |
848 | raise FrozenInstanceError() |
|
848 | raise FrozenInstanceError() | |
849 |
|
849 | |||
850 | @classmethod |
|
850 | @classmethod | |
851 | def from_counting_attr(cls, name, ca): |
|
851 | def from_counting_attr(cls, name, ca): | |
852 | inst_dict = { |
|
852 | inst_dict = { | |
853 | k: getattr(ca, k) |
|
853 | k: getattr(ca, k) | |
854 | for k |
|
854 | for k | |
855 | in Attribute.__slots__ |
|
855 | in Attribute.__slots__ | |
856 | if k not in ( |
|
856 | if k not in ( | |
857 | "name", "validator", "default", |
|
857 | "name", "validator", "default", | |
858 | ) # exclude methods |
|
858 | ) # exclude methods | |
859 | } |
|
859 | } | |
860 | return cls(name=name, validator=ca._validator, default=ca._default, |
|
860 | return cls(name=name, validator=ca._validator, default=ca._default, | |
861 | **inst_dict) |
|
861 | **inst_dict) | |
862 |
|
862 | |||
863 | # Don't use _add_pickle since fields(Attribute) doesn't work |
|
863 | # Don't use _add_pickle since fields(Attribute) doesn't work | |
864 | def __getstate__(self): |
|
864 | def __getstate__(self): | |
865 | """ |
|
865 | """ | |
866 | Play nice with pickle. |
|
866 | Play nice with pickle. | |
867 | """ |
|
867 | """ | |
868 | return tuple(getattr(self, name) if name != "metadata" |
|
868 | return tuple(getattr(self, name) if name != "metadata" | |
869 | else dict(self.metadata) |
|
869 | else dict(self.metadata) | |
870 | for name in self.__slots__) |
|
870 | for name in self.__slots__) | |
871 |
|
871 | |||
872 | def __setstate__(self, state): |
|
872 | def __setstate__(self, state): | |
873 | """ |
|
873 | """ | |
874 | Play nice with pickle. |
|
874 | Play nice with pickle. | |
875 | """ |
|
875 | """ | |
876 | bound_setattr = _obj_setattr.__get__(self, Attribute) |
|
876 | bound_setattr = _obj_setattr.__get__(self, Attribute) | |
877 | for name, value in zip(self.__slots__, state): |
|
877 | for name, value in zip(self.__slots__, state): | |
878 | if name != "metadata": |
|
878 | if name != "metadata": | |
879 | bound_setattr(name, value) |
|
879 | bound_setattr(name, value) | |
880 | else: |
|
880 | else: | |
881 | bound_setattr(name, metadata_proxy(value) if value else |
|
881 | bound_setattr(name, metadata_proxy(value) if value else | |
882 | _empty_metadata_singleton) |
|
882 | _empty_metadata_singleton) | |
883 |
|
883 | |||
884 |
|
884 | |||
885 | _a = [Attribute(name=name, default=NOTHING, validator=None, |
|
885 | _a = [Attribute(name=name, default=NOTHING, validator=None, | |
886 | repr=True, cmp=True, hash=(name != "metadata"), init=True) |
|
886 | repr=True, cmp=True, hash=(name != "metadata"), init=True) | |
887 | for name in Attribute.__slots__] |
|
887 | for name in Attribute.__slots__] | |
888 |
|
888 | |||
889 | Attribute = _add_hash( |
|
889 | Attribute = _add_hash( | |
890 | _add_cmp(_add_repr(Attribute, attrs=_a), attrs=_a), |
|
890 | _add_cmp(_add_repr(Attribute, attrs=_a), attrs=_a), | |
891 | attrs=[a for a in _a if a.hash] |
|
891 | attrs=[a for a in _a if a.hash] | |
892 | ) |
|
892 | ) | |
893 |
|
893 | |||
894 |
|
894 | |||
895 | class _CountingAttr(object): |
|
895 | class _CountingAttr(object): | |
896 | """ |
|
896 | """ | |
897 | Intermediate representation of attributes that uses a counter to preserve |
|
897 | Intermediate representation of attributes that uses a counter to preserve | |
898 | the order in which the attributes have been defined. |
|
898 | the order in which the attributes have been defined. | |
899 |
|
899 | |||
900 | *Internal* data structure of the attrs library. Running into is most |
|
900 | *Internal* data structure of the attrs library. Running into is most | |
901 | likely the result of a bug like a forgotten `@attr.s` decorator. |
|
901 | likely the result of a bug like a forgotten `@attr.s` decorator. | |
902 | """ |
|
902 | """ | |
903 | __slots__ = ("counter", "_default", "repr", "cmp", "hash", "init", |
|
903 | __slots__ = ("counter", "_default", "repr", "cmp", "hash", "init", | |
904 | "metadata", "_validator", "convert") |
|
904 | "metadata", "_validator", "convert") | |
905 | __attrs_attrs__ = tuple( |
|
905 | __attrs_attrs__ = tuple( | |
906 | Attribute(name=name, default=NOTHING, validator=None, |
|
906 | Attribute(name=name, default=NOTHING, validator=None, | |
907 | repr=True, cmp=True, hash=True, init=True) |
|
907 | repr=True, cmp=True, hash=True, init=True) | |
908 | for name |
|
908 | for name | |
909 | in ("counter", "_default", "repr", "cmp", "hash", "init",) |
|
909 | in ("counter", "_default", "repr", "cmp", "hash", "init",) | |
910 | ) + ( |
|
910 | ) + ( | |
911 | Attribute(name="metadata", default=None, validator=None, |
|
911 | Attribute(name="metadata", default=None, validator=None, | |
912 | repr=True, cmp=True, hash=False, init=True), |
|
912 | repr=True, cmp=True, hash=False, init=True), | |
913 | ) |
|
913 | ) | |
914 | cls_counter = 0 |
|
914 | cls_counter = 0 | |
915 |
|
915 | |||
916 | def __init__(self, default, validator, repr, cmp, hash, init, convert, |
|
916 | def __init__(self, default, validator, repr, cmp, hash, init, convert, | |
917 | metadata): |
|
917 | metadata): | |
918 | _CountingAttr.cls_counter += 1 |
|
918 | _CountingAttr.cls_counter += 1 | |
919 | self.counter = _CountingAttr.cls_counter |
|
919 | self.counter = _CountingAttr.cls_counter | |
920 | self._default = default |
|
920 | self._default = default | |
921 | # If validator is a list/tuple, wrap it using helper validator. |
|
921 | # If validator is a list/tuple, wrap it using helper validator. | |
922 | if validator and isinstance(validator, (list, tuple)): |
|
922 | if validator and isinstance(validator, (list, tuple)): | |
923 | self._validator = and_(*validator) |
|
923 | self._validator = and_(*validator) | |
924 | else: |
|
924 | else: | |
925 | self._validator = validator |
|
925 | self._validator = validator | |
926 | self.repr = repr |
|
926 | self.repr = repr | |
927 | self.cmp = cmp |
|
927 | self.cmp = cmp | |
928 | self.hash = hash |
|
928 | self.hash = hash | |
929 | self.init = init |
|
929 | self.init = init | |
930 | self.convert = convert |
|
930 | self.convert = convert | |
931 | self.metadata = metadata |
|
931 | self.metadata = metadata | |
932 |
|
932 | |||
933 | def validator(self, meth): |
|
933 | def validator(self, meth): | |
934 | """ |
|
934 | """ | |
935 | Decorator that adds *meth* to the list of validators. |
|
935 | Decorator that adds *meth* to the list of validators. | |
936 |
|
936 | |||
937 | Returns *meth* unchanged. |
|
937 | Returns *meth* unchanged. | |
938 |
|
938 | |||
939 | .. versionadded:: 17.1.0 |
|
939 | .. versionadded:: 17.1.0 | |
940 | """ |
|
940 | """ | |
941 | if self._validator is None: |
|
941 | if self._validator is None: | |
942 | self._validator = meth |
|
942 | self._validator = meth | |
943 | else: |
|
943 | else: | |
944 | self._validator = and_(self._validator, meth) |
|
944 | self._validator = and_(self._validator, meth) | |
945 | return meth |
|
945 | return meth | |
946 |
|
946 | |||
947 | def default(self, meth): |
|
947 | def default(self, meth): | |
948 | """ |
|
948 | """ | |
949 | Decorator that allows to set the default for an attribute. |
|
949 | Decorator that allows to set the default for an attribute. | |
950 |
|
950 | |||
951 | Returns *meth* unchanged. |
|
951 | Returns *meth* unchanged. | |
952 |
|
952 | |||
953 | :raises DefaultAlreadySetError: If default has been set before. |
|
953 | :raises DefaultAlreadySetError: If default has been set before. | |
954 |
|
954 | |||
955 | .. versionadded:: 17.1.0 |
|
955 | .. versionadded:: 17.1.0 | |
956 | """ |
|
956 | """ | |
957 | if self._default is not NOTHING: |
|
957 | if self._default is not NOTHING: | |
958 | raise DefaultAlreadySetError() |
|
958 | raise DefaultAlreadySetError() | |
959 |
|
959 | |||
960 | self._default = Factory(meth, takes_self=True) |
|
960 | self._default = Factory(meth, takes_self=True) | |
961 |
|
961 | |||
962 | return meth |
|
962 | return meth | |
963 |
|
963 | |||
964 |
|
964 | |||
965 | _CountingAttr = _add_cmp(_add_repr(_CountingAttr)) |
|
965 | _CountingAttr = _add_cmp(_add_repr(_CountingAttr)) | |
966 |
|
966 | |||
967 |
|
967 | |||
968 | @attributes(slots=True, init=False) |
|
968 | @attributes(slots=True, init=False) | |
969 | class Factory(object): |
|
969 | class Factory(object): | |
970 | """ |
|
970 | """ | |
971 | Stores a factory callable. |
|
971 | Stores a factory callable. | |
972 |
|
972 | |||
973 | If passed as the default value to :func:`attr.ib`, the factory is used to |
|
973 | If passed as the default value to :func:`attr.ib`, the factory is used to | |
974 | generate a new value. |
|
974 | generate a new value. | |
975 |
|
975 | |||
976 | :param callable factory: A callable that takes either none or exactly one |
|
976 | :param callable factory: A callable that takes either none or exactly one | |
977 | mandatory positional argument depending on *takes_self*. |
|
977 | mandatory positional argument depending on *takes_self*. | |
978 | :param bool takes_self: Pass the partially initialized instance that is |
|
978 | :param bool takes_self: Pass the partially initialized instance that is | |
979 | being initialized as a positional argument. |
|
979 | being initialized as a positional argument. | |
980 |
|
980 | |||
981 | .. versionadded:: 17.1.0 *takes_self* |
|
981 | .. versionadded:: 17.1.0 *takes_self* | |
982 | """ |
|
982 | """ | |
983 | factory = attr() |
|
983 | factory = attr() | |
984 | takes_self = attr() |
|
984 | takes_self = attr() | |
985 |
|
985 | |||
986 | def __init__(self, factory, takes_self=False): |
|
986 | def __init__(self, factory, takes_self=False): | |
987 | """ |
|
987 | """ | |
988 | `Factory` is part of the default machinery so if we want a default |
|
988 | `Factory` is part of the default machinery so if we want a default | |
989 | value here, we have to implement it ourselves. |
|
989 | value here, we have to implement it ourselves. | |
990 | """ |
|
990 | """ | |
991 | self.factory = factory |
|
991 | self.factory = factory | |
992 | self.takes_self = takes_self |
|
992 | self.takes_self = takes_self | |
993 |
|
993 | |||
994 |
|
994 | |||
995 | def make_class(name, attrs, bases=(object,), **attributes_arguments): |
|
995 | def make_class(name, attrs, bases=(object,), **attributes_arguments): | |
996 | """ |
|
996 | """ | |
997 | A quick way to create a new class called *name* with *attrs*. |
|
997 | A quick way to create a new class called *name* with *attrs*. | |
998 |
|
998 | |||
999 | :param name: The name for the new class. |
|
999 | :param name: The name for the new class. | |
1000 | :type name: str |
|
1000 | :type name: str | |
1001 |
|
1001 | |||
1002 | :param attrs: A list of names or a dictionary of mappings of names to |
|
1002 | :param attrs: A list of names or a dictionary of mappings of names to | |
1003 | attributes. |
|
1003 | attributes. | |
1004 | :type attrs: :class:`list` or :class:`dict` |
|
1004 | :type attrs: :class:`list` or :class:`dict` | |
1005 |
|
1005 | |||
1006 | :param tuple bases: Classes that the new class will subclass. |
|
1006 | :param tuple bases: Classes that the new class will subclass. | |
1007 |
|
1007 | |||
1008 | :param attributes_arguments: Passed unmodified to :func:`attr.s`. |
|
1008 | :param attributes_arguments: Passed unmodified to :func:`attr.s`. | |
1009 |
|
1009 | |||
1010 | :return: A new class with *attrs*. |
|
1010 | :return: A new class with *attrs*. | |
1011 | :rtype: type |
|
1011 | :rtype: type | |
1012 |
|
1012 | |||
1013 | .. versionadded:: 17.1.0 *bases* |
|
1013 | .. versionadded:: 17.1.0 *bases* | |
1014 | """ |
|
1014 | """ | |
1015 | if isinstance(attrs, dict): |
|
1015 | if isinstance(attrs, dict): | |
1016 | cls_dict = attrs |
|
1016 | cls_dict = attrs | |
1017 | elif isinstance(attrs, (list, tuple)): |
|
1017 | elif isinstance(attrs, (list, tuple)): | |
1018 | cls_dict = dict((a, attr()) for a in attrs) |
|
1018 | cls_dict = dict((a, attr()) for a in attrs) | |
1019 | else: |
|
1019 | else: | |
1020 | raise TypeError("attrs argument must be a dict or a list.") |
|
1020 | raise TypeError("attrs argument must be a dict or a list.") | |
1021 |
|
1021 | |||
1022 | return attributes(**attributes_arguments)(type(name, bases, cls_dict)) |
|
1022 | return attributes(**attributes_arguments)(type(name, bases, cls_dict)) | |
1023 |
|
1023 | |||
1024 |
|
1024 | |||
1025 | # These are required by whithin this module so we define them here and merely |
|
1025 | # These are required by whithin this module so we define them here and merely | |
1026 | # import into .validators. |
|
1026 | # import into .validators. | |
1027 |
|
1027 | |||
1028 |
|
1028 | |||
1029 | @attributes(slots=True, hash=True) |
|
1029 | @attributes(slots=True, hash=True) | |
1030 | class _AndValidator(object): |
|
1030 | class _AndValidator(object): | |
1031 | """ |
|
1031 | """ | |
1032 | Compose many validators to a single one. |
|
1032 | Compose many validators to a single one. | |
1033 | """ |
|
1033 | """ | |
1034 | _validators = attr() |
|
1034 | _validators = attr() | |
1035 |
|
1035 | |||
1036 | def __call__(self, inst, attr, value): |
|
1036 | def __call__(self, inst, attr, value): | |
1037 | for v in self._validators: |
|
1037 | for v in self._validators: | |
1038 | v(inst, attr, value) |
|
1038 | v(inst, attr, value) | |
1039 |
|
1039 | |||
1040 |
|
1040 | |||
1041 | def and_(*validators): |
|
1041 | def and_(*validators): | |
1042 | """ |
|
1042 | """ | |
1043 | A validator that composes multiple validators into one. |
|
1043 | A validator that composes multiple validators into one. | |
1044 |
|
1044 | |||
1045 | When called on a value, it runs all wrapped validators. |
|
1045 | When called on a value, it runs all wrapped validators. | |
1046 |
|
1046 | |||
1047 | :param validators: Arbitrary number of validators. |
|
1047 | :param validators: Arbitrary number of validators. | |
1048 | :type validators: callables |
|
1048 | :type validators: callables | |
1049 |
|
1049 | |||
1050 | .. versionadded:: 17.1.0 |
|
1050 | .. versionadded:: 17.1.0 | |
1051 | """ |
|
1051 | """ | |
1052 | vals = [] |
|
1052 | vals = [] | |
1053 | for validator in validators: |
|
1053 | for validator in validators: | |
1054 | vals.extend( |
|
1054 | vals.extend( | |
1055 | validator._validators if isinstance(validator, _AndValidator) |
|
1055 | validator._validators if isinstance(validator, _AndValidator) | |
1056 | else [validator] |
|
1056 | else [validator] | |
1057 | ) |
|
1057 | ) | |
1058 |
|
1058 | |||
1059 | return _AndValidator(tuple(vals)) |
|
1059 | return _AndValidator(tuple(vals)) |
@@ -1,52 +1,52 b'' | |||||
1 | """ |
|
1 | """ | |
2 | Commonly useful filters for :func:`attr.asdict`. |
|
2 | Commonly useful filters for :func:`attr.asdict`. | |
3 | """ |
|
3 | """ | |
4 |
|
4 | |||
5 | from __future__ import absolute_import, division, print_function |
|
5 | from __future__ import absolute_import, division, print_function | |
6 |
|
6 | |||
7 | from ._compat import isclass |
|
7 | from ._compat import isclass | |
8 | from ._make import Attribute |
|
8 | from ._make import Attribute | |
9 |
|
9 | |||
10 |
|
10 | |||
11 | def _split_what(what): |
|
11 | def _split_what(what): | |
12 | """ |
|
12 | """ | |
13 | Returns a tuple of `frozenset`s of classes and attributes. |
|
13 | Returns a tuple of `frozenset`s of classes and attributes. | |
14 | """ |
|
14 | """ | |
15 | return ( |
|
15 | return ( | |
16 | frozenset(cls for cls in what if isclass(cls)), |
|
16 | frozenset(cls for cls in what if isclass(cls)), | |
17 | frozenset(cls for cls in what if isinstance(cls, Attribute)), |
|
17 | frozenset(cls for cls in what if isinstance(cls, Attribute)), | |
18 | ) |
|
18 | ) | |
19 |
|
19 | |||
20 |
|
20 | |||
21 | def include(*what): |
|
21 | def include(*what): | |
22 | """ |
|
22 | r""" | |
23 | Whitelist *what*. |
|
23 | Whitelist *what*. | |
24 |
|
24 | |||
25 | :param what: What to whitelist. |
|
25 | :param what: What to whitelist. | |
26 | :type what: :class:`list` of :class:`type` or :class:`attr.Attribute`\ s |
|
26 | :type what: :class:`list` of :class:`type` or :class:`attr.Attribute`\ s | |
27 |
|
27 | |||
28 | :rtype: :class:`callable` |
|
28 | :rtype: :class:`callable` | |
29 | """ |
|
29 | """ | |
30 | cls, attrs = _split_what(what) |
|
30 | cls, attrs = _split_what(what) | |
31 |
|
31 | |||
32 | def include_(attribute, value): |
|
32 | def include_(attribute, value): | |
33 | return value.__class__ in cls or attribute in attrs |
|
33 | return value.__class__ in cls or attribute in attrs | |
34 |
|
34 | |||
35 | return include_ |
|
35 | return include_ | |
36 |
|
36 | |||
37 |
|
37 | |||
38 | def exclude(*what): |
|
38 | def exclude(*what): | |
39 | """ |
|
39 | r""" | |
40 | Blacklist *what*. |
|
40 | Blacklist *what*. | |
41 |
|
41 | |||
42 | :param what: What to blacklist. |
|
42 | :param what: What to blacklist. | |
43 | :type what: :class:`list` of classes or :class:`attr.Attribute`\ s. |
|
43 | :type what: :class:`list` of classes or :class:`attr.Attribute`\ s. | |
44 |
|
44 | |||
45 | :rtype: :class:`callable` |
|
45 | :rtype: :class:`callable` | |
46 | """ |
|
46 | """ | |
47 | cls, attrs = _split_what(what) |
|
47 | cls, attrs = _split_what(what) | |
48 |
|
48 | |||
49 | def exclude_(attribute, value): |
|
49 | def exclude_(attribute, value): | |
50 | return value.__class__ not in cls and attribute not in attrs |
|
50 | return value.__class__ not in cls and attribute not in attrs | |
51 |
|
51 | |||
52 | return exclude_ |
|
52 | return exclude_ |
General Comments 0
You need to be logged in to leave comments.
Login now