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Diffstat (limited to '.venv/lib/python3.12/site-packages/attr/_funcs.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/attr/_funcs.py | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/attr/_funcs.py b/.venv/lib/python3.12/site-packages/attr/_funcs.py new file mode 100644 index 00000000..c39fb8aa --- /dev/null +++ b/.venv/lib/python3.12/site-packages/attr/_funcs.py @@ -0,0 +1,468 @@ +# SPDX-License-Identifier: MIT + + +import copy + +from ._compat import PY_3_9_PLUS, get_generic_base +from ._make import _OBJ_SETATTR, NOTHING, fields +from .exceptions import AttrsAttributeNotFoundError + + +def asdict( + inst, + recurse=True, + filter=None, + dict_factory=dict, + retain_collection_types=False, + value_serializer=None, +): + """ + Return the *attrs* attribute values of *inst* as a dict. + + Optionally recurse into other *attrs*-decorated classes. + + Args: + inst: Instance of an *attrs*-decorated class. + + recurse (bool): Recurse into classes that are also *attrs*-decorated. + + filter (~typing.Callable): + A callable whose return code determines whether an attribute or + element is included (`True`) or dropped (`False`). Is called with + the `attrs.Attribute` as the first argument and the value as the + second argument. + + dict_factory (~typing.Callable): + A callable to produce dictionaries from. For example, to produce + ordered dictionaries instead of normal Python dictionaries, pass in + ``collections.OrderedDict``. + + retain_collection_types (bool): + Do not convert to `list` when encountering an attribute whose type + is `tuple` or `set`. Only meaningful if *recurse* is `True`. + + value_serializer (typing.Callable | None): + A hook that is called for every attribute or dict key/value. It + receives the current instance, field and value and must return the + (updated) value. The hook is run *after* the optional *filter* has + been applied. + + Returns: + Return type of *dict_factory*. + + Raises: + attrs.exceptions.NotAnAttrsClassError: + If *cls* is not an *attrs* class. + + .. versionadded:: 16.0.0 *dict_factory* + .. versionadded:: 16.1.0 *retain_collection_types* + .. versionadded:: 20.3.0 *value_serializer* + .. versionadded:: 21.3.0 + If a dict has a collection for a key, it is serialized as a tuple. + """ + attrs = fields(inst.__class__) + rv = dict_factory() + for a in attrs: + v = getattr(inst, a.name) + if filter is not None and not filter(a, v): + continue + + if value_serializer is not None: + v = value_serializer(inst, a, v) + + if recurse is True: + if has(v.__class__): + rv[a.name] = asdict( + v, + recurse=True, + filter=filter, + dict_factory=dict_factory, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ) + elif isinstance(v, (tuple, list, set, frozenset)): + cf = v.__class__ if retain_collection_types is True else list + items = [ + _asdict_anything( + i, + is_key=False, + filter=filter, + dict_factory=dict_factory, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ) + for i in v + ] + try: + rv[a.name] = cf(items) + except TypeError: + if not issubclass(cf, tuple): + raise + # Workaround for TypeError: cf.__new__() missing 1 required + # positional argument (which appears, for a namedturle) + rv[a.name] = cf(*items) + elif isinstance(v, dict): + df = dict_factory + rv[a.name] = df( + ( + _asdict_anything( + kk, + is_key=True, + filter=filter, + dict_factory=df, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ), + _asdict_anything( + vv, + is_key=False, + filter=filter, + dict_factory=df, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ), + ) + for kk, vv in v.items() + ) + else: + rv[a.name] = v + else: + rv[a.name] = v + return rv + + +def _asdict_anything( + val, + is_key, + filter, + dict_factory, + retain_collection_types, + value_serializer, +): + """ + ``asdict`` only works on attrs instances, this works on anything. + """ + if getattr(val.__class__, "__attrs_attrs__", None) is not None: + # Attrs class. + rv = asdict( + val, + recurse=True, + filter=filter, + dict_factory=dict_factory, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ) + elif isinstance(val, (tuple, list, set, frozenset)): + if retain_collection_types is True: + cf = val.__class__ + elif is_key: + cf = tuple + else: + cf = list + + rv = cf( + [ + _asdict_anything( + i, + is_key=False, + filter=filter, + dict_factory=dict_factory, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ) + for i in val + ] + ) + elif isinstance(val, dict): + df = dict_factory + rv = df( + ( + _asdict_anything( + kk, + is_key=True, + filter=filter, + dict_factory=df, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ), + _asdict_anything( + vv, + is_key=False, + filter=filter, + dict_factory=df, + retain_collection_types=retain_collection_types, + value_serializer=value_serializer, + ), + ) + for kk, vv in val.items() + ) + else: + rv = val + if value_serializer is not None: + rv = value_serializer(None, None, rv) + + return rv + + +def astuple( + inst, + recurse=True, + filter=None, + tuple_factory=tuple, + retain_collection_types=False, +): + """ + Return the *attrs* attribute values of *inst* as a tuple. + + Optionally recurse into other *attrs*-decorated classes. + + Args: + inst: Instance of an *attrs*-decorated class. + + recurse (bool): + Recurse into classes that are also *attrs*-decorated. + + filter (~typing.Callable): + A callable whose return code determines whether an attribute or + element is included (`True`) or dropped (`False`). Is called with + the `attrs.Attribute` as the first argument and the value as the + second argument. + + tuple_factory (~typing.Callable): + A callable to produce tuples from. For example, to produce lists + instead of tuples. + + retain_collection_types (bool): + Do not convert to `list` or `dict` when encountering an attribute + which type is `tuple`, `dict` or `set`. Only meaningful if + *recurse* is `True`. + + Returns: + Return type of *tuple_factory* + + Raises: + attrs.exceptions.NotAnAttrsClassError: + If *cls* is not an *attrs* class. + + .. versionadded:: 16.2.0 + """ + attrs = fields(inst.__class__) + rv = [] + retain = retain_collection_types # Very long. :/ + for a in attrs: + v = getattr(inst, a.name) + if filter is not None and not filter(a, v): + continue + if recurse is True: + if has(v.__class__): + rv.append( + astuple( + v, + recurse=True, + filter=filter, + tuple_factory=tuple_factory, + retain_collection_types=retain, + ) + ) + elif isinstance(v, (tuple, list, set, frozenset)): + cf = v.__class__ if retain is True else list + items = [ + ( + astuple( + j, + recurse=True, + filter=filter, + tuple_factory=tuple_factory, + retain_collection_types=retain, + ) + if has(j.__class__) + else j + ) + for j in v + ] + try: + rv.append(cf(items)) + except TypeError: + if not issubclass(cf, tuple): + raise + # Workaround for TypeError: cf.__new__() missing 1 required + # positional argument (which appears, for a namedturle) + rv.append(cf(*items)) + elif isinstance(v, dict): + df = v.__class__ if retain is True else dict + rv.append( + df( + ( + ( + astuple( + kk, + tuple_factory=tuple_factory, + retain_collection_types=retain, + ) + if has(kk.__class__) + else kk + ), + ( + astuple( + vv, + tuple_factory=tuple_factory, + retain_collection_types=retain, + ) + if has(vv.__class__) + else vv + ), + ) + for kk, vv in v.items() + ) + ) + else: + rv.append(v) + else: + rv.append(v) + + return rv if tuple_factory is list else tuple_factory(rv) + + +def has(cls): + """ + Check whether *cls* is a class with *attrs* attributes. + + Args: + cls (type): Class to introspect. + + Raises: + TypeError: If *cls* is not a class. + + Returns: + bool: + """ + attrs = getattr(cls, "__attrs_attrs__", None) + if attrs is not None: + return True + + # No attrs, maybe it's a specialized generic (A[str])? + generic_base = get_generic_base(cls) + if generic_base is not None: + generic_attrs = getattr(generic_base, "__attrs_attrs__", None) + if generic_attrs is not None: + # Stick it on here for speed next time. + cls.__attrs_attrs__ = generic_attrs + return generic_attrs is not None + return False + + +def assoc(inst, **changes): + """ + Copy *inst* and apply *changes*. + + This is different from `evolve` that applies the changes to the arguments + that create the new instance. + + `evolve`'s behavior is preferable, but there are `edge cases`_ where it + doesn't work. Therefore `assoc` is deprecated, but will not be removed. + + .. _`edge cases`: https://github.com/python-attrs/attrs/issues/251 + + Args: + inst: Instance of a class with *attrs* attributes. + + changes: Keyword changes in the new copy. + + Returns: + A copy of inst with *changes* incorporated. + + Raises: + attrs.exceptions.AttrsAttributeNotFoundError: + If *attr_name* couldn't be found on *cls*. + + attrs.exceptions.NotAnAttrsClassError: + If *cls* is not an *attrs* class. + + .. deprecated:: 17.1.0 + Use `attrs.evolve` instead if you can. This function will not be + removed du to the slightly different approach compared to + `attrs.evolve`, though. + """ + new = copy.copy(inst) + attrs = fields(inst.__class__) + for k, v in changes.items(): + a = getattr(attrs, k, NOTHING) + if a is NOTHING: + msg = f"{k} is not an attrs attribute on {new.__class__}." + raise AttrsAttributeNotFoundError(msg) + _OBJ_SETATTR(new, k, v) + return new + + +def resolve_types( + cls, globalns=None, localns=None, attribs=None, include_extras=True +): + """ + Resolve any strings and forward annotations in type annotations. + + This is only required if you need concrete types in :class:`Attribute`'s + *type* field. In other words, you don't need to resolve your types if you + only use them for static type checking. + + With no arguments, names will be looked up in the module in which the class + was created. If this is not what you want, for example, if the name only + exists inside a method, you may pass *globalns* or *localns* to specify + other dictionaries in which to look up these names. See the docs of + `typing.get_type_hints` for more details. + + Args: + cls (type): Class to resolve. + + globalns (dict | None): Dictionary containing global variables. + + localns (dict | None): Dictionary containing local variables. + + attribs (list | None): + List of attribs for the given class. This is necessary when calling + from inside a ``field_transformer`` since *cls* is not an *attrs* + class yet. + + include_extras (bool): + Resolve more accurately, if possible. Pass ``include_extras`` to + ``typing.get_hints``, if supported by the typing module. On + supported Python versions (3.9+), this resolves the types more + accurately. + + Raises: + TypeError: If *cls* is not a class. + + attrs.exceptions.NotAnAttrsClassError: + If *cls* is not an *attrs* class and you didn't pass any attribs. + + NameError: If types cannot be resolved because of missing variables. + + Returns: + *cls* so you can use this function also as a class decorator. Please + note that you have to apply it **after** `attrs.define`. That means the + decorator has to come in the line **before** `attrs.define`. + + .. versionadded:: 20.1.0 + .. versionadded:: 21.1.0 *attribs* + .. versionadded:: 23.1.0 *include_extras* + """ + # Since calling get_type_hints is expensive we cache whether we've + # done it already. + if getattr(cls, "__attrs_types_resolved__", None) != cls: + import typing + + kwargs = {"globalns": globalns, "localns": localns} + + if PY_3_9_PLUS: + kwargs["include_extras"] = include_extras + + hints = typing.get_type_hints(cls, **kwargs) + for field in fields(cls) if attribs is None else attribs: + if field.name in hints: + # Since fields have been frozen we must work around it. + _OBJ_SETATTR(field, "type", hints[field.name]) + # We store the class we resolved so that subclasses know they haven't + # been resolved. + cls.__attrs_types_resolved__ = cls + + # Return the class so you can use it as a decorator too. + return cls |