mercurial/thirdparty/attr/__init__.pyi

interfaces: introduce and use a protocol class for the `charencoding` module

See f2832de2a46c for details when this was done for the `bdiff` module.

This lets us dump the hack where the `pure` implementation was imported during
the type checking phase to provide signatures for the module methods it
provides.  Now the protocol classes are starting to shine, because these methods
are provided by `pure.charencoding` and `cext.parsers`, and references to
`cffi.charencoding` and `cext.charencoding` are forwarded to them as appropriate
by the `policy` module.  But none of that matters, as long as the module
returned provides the listed methods.

The interface was copy/pasted from the `pure` module, but `jsonescapeu8fallback`
is omitted because it is accessed from the `pure` module directly when the
escaping fails in the primary module's `jsonescapeu8()`.

import sys

from typing import (
    Any,
    Callable,
    ClassVar,
    Dict,
    Generic,
    List,
    Mapping,
    Optional,
    Protocol,
    Sequence,
    Tuple,
    Type,
    TypeVar,
    Union,
    overload,
)

# `import X as X` is required to make these public
from . import converters as converters
from . import exceptions as exceptions
from . import filters as filters
from . import setters as setters
from . import validators as validators
from ._cmp import cmp_using as cmp_using
from ._version_info import VersionInfo

__version__: str
__version_info__: VersionInfo
__title__: str
__description__: str
__url__: str
__uri__: str
__author__: str
__email__: str
__license__: str
__copyright__: str

_T = TypeVar("_T")
_C = TypeVar("_C", bound=type)

_EqOrderType = Union[bool, Callable[[Any], Any]]
_ValidatorType = Callable[[Any, Attribute[_T], _T], Any]
_ConverterType = Callable[[Any], Any]
_FilterType = Callable[[Attribute[_T], _T], bool]
_ReprType = Callable[[Any], str]
_ReprArgType = Union[bool, _ReprType]
_OnSetAttrType = Callable[[Any, Attribute[Any], Any], Any]
_OnSetAttrArgType = Union[
    _OnSetAttrType, List[_OnSetAttrType], setters._NoOpType
]
_FieldTransformer = Callable[
    [type, List[Attribute[Any]]], List[Attribute[Any]]
]
# FIXME: in reality, if multiple validators are passed they must be in a list
# or tuple, but those are invariant and so would prevent subtypes of
# _ValidatorType from working when passed in a list or tuple.
_ValidatorArgType = Union[_ValidatorType[_T], Sequence[_ValidatorType[_T]]]

# A protocol to be able to statically accept an attrs class.
class AttrsInstance(Protocol):
    __attrs_attrs__: ClassVar[Any]

# _make --

NOTHING: object

# NOTE: Factory lies about its return type to make this possible:
# `x: List[int] # = Factory(list)`
# Work around mypy issue #4554 in the common case by using an overload.
if sys.version_info >= (3, 8):
    from typing import Literal
    @overload
    def Factory(factory: Callable[[], _T]) -> _T: ...
    @overload
    def Factory(
        factory: Callable[[Any], _T],
        takes_self: Literal[True],
    ) -> _T: ...
    @overload
    def Factory(
        factory: Callable[[], _T],
        takes_self: Literal[False],
    ) -> _T: ...

else:
    @overload
    def Factory(factory: Callable[[], _T]) -> _T: ...
    @overload
    def Factory(
        factory: Union[Callable[[Any], _T], Callable[[], _T]],
        takes_self: bool = ...,
    ) -> _T: ...

# Static type inference support via __dataclass_transform__ implemented as per:
# https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
# This annotation must be applied to all overloads of "define" and "attrs"
#
# NOTE: This is a typing construct and does not exist at runtime.  Extensions
# wrapping attrs decorators should declare a separate __dataclass_transform__
# signature in the extension module using the specification linked above to
# provide pyright support.
def __dataclass_transform__(
    *,
    eq_default: bool = True,
    order_default: bool = False,
    kw_only_default: bool = False,
    field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
) -> Callable[[_T], _T]: ...

class Attribute(Generic[_T]):
    name: str
    default: Optional[_T]
    validator: Optional[_ValidatorType[_T]]
    repr: _ReprArgType
    cmp: _EqOrderType
    eq: _EqOrderType
    order: _EqOrderType
    hash: Optional[bool]
    init: bool
    converter: Optional[_ConverterType]
    metadata: Dict[Any, Any]
    type: Optional[Type[_T]]
    kw_only: bool
    on_setattr: _OnSetAttrType
    def evolve(self, **changes: Any) -> "Attribute[Any]": ...

# NOTE: We had several choices for the annotation to use for type arg:
# 1) Type[_T]
#   - Pros: Handles simple cases correctly
#   - Cons: Might produce less informative errors in the case of conflicting
#     TypeVars e.g. `attr.ib(default='bad', type=int)`
# 2) Callable[..., _T]
#   - Pros: Better error messages than #1 for conflicting TypeVars
#   - Cons: Terrible error messages for validator checks.
#   e.g. attr.ib(type=int, validator=validate_str)
#        -> error: Cannot infer function type argument
# 3) type (and do all of the work in the mypy plugin)
#   - Pros: Simple here, and we could customize the plugin with our own errors.
#   - Cons: Would need to write mypy plugin code to handle all the cases.
# We chose option #1.

# `attr` lies about its return type to make the following possible:
#     attr()    -> Any
#     attr(8)   -> int
#     attr(validator=<some callable>)  -> Whatever the callable expects.
# This makes this type of assignments possible:
#     x: int = attr(8)
#
# This form catches explicit None or no default but with no other arguments
# returns Any.
@overload
def attrib(
    default: None = ...,
    validator: None = ...,
    repr: _ReprArgType = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    type: None = ...,
    converter: None = ...,
    factory: None = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> Any: ...

# This form catches an explicit None or no default and infers the type from the
# other arguments.
@overload
def attrib(
    default: None = ...,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    type: Optional[Type[_T]] = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> _T: ...

# This form catches an explicit default argument.
@overload
def attrib(
    default: _T,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    type: Optional[Type[_T]] = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> _T: ...

# This form covers type=non-Type: e.g. forward references (str), Any
@overload
def attrib(
    default: Optional[_T] = ...,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    type: object = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> Any: ...
@overload
def field(
    *,
    default: None = ...,
    validator: None = ...,
    repr: _ReprArgType = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    converter: None = ...,
    factory: None = ...,
    kw_only: bool = ...,
    eq: Optional[bool] = ...,
    order: Optional[bool] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> Any: ...

# This form catches an explicit None or no default and infers the type from the
# other arguments.
@overload
def field(
    *,
    default: None = ...,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> _T: ...

# This form catches an explicit default argument.
@overload
def field(
    *,
    default: _T,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> _T: ...

# This form covers type=non-Type: e.g. forward references (str), Any
@overload
def field(
    *,
    default: Optional[_T] = ...,
    validator: Optional[_ValidatorArgType[_T]] = ...,
    repr: _ReprArgType = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    metadata: Optional[Mapping[Any, Any]] = ...,
    converter: Optional[_ConverterType] = ...,
    factory: Optional[Callable[[], _T]] = ...,
    kw_only: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
) -> Any: ...
@overload
@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
def attrs(
    maybe_cls: _C,
    these: Optional[Dict[str, Any]] = ...,
    repr_ns: Optional[str] = ...,
    repr: bool = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    slots: bool = ...,
    frozen: bool = ...,
    weakref_slot: bool = ...,
    str: bool = ...,
    auto_attribs: bool = ...,
    kw_only: bool = ...,
    cache_hash: bool = ...,
    auto_exc: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    auto_detect: bool = ...,
    collect_by_mro: bool = ...,
    getstate_setstate: Optional[bool] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
    match_args: bool = ...,
) -> _C: ...
@overload
@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
def attrs(
    maybe_cls: None = ...,
    these: Optional[Dict[str, Any]] = ...,
    repr_ns: Optional[str] = ...,
    repr: bool = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    slots: bool = ...,
    frozen: bool = ...,
    weakref_slot: bool = ...,
    str: bool = ...,
    auto_attribs: bool = ...,
    kw_only: bool = ...,
    cache_hash: bool = ...,
    auto_exc: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    auto_detect: bool = ...,
    collect_by_mro: bool = ...,
    getstate_setstate: Optional[bool] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
    match_args: bool = ...,
) -> Callable[[_C], _C]: ...
@overload
@__dataclass_transform__(field_descriptors=(attrib, field))
def define(
    maybe_cls: _C,
    *,
    these: Optional[Dict[str, Any]] = ...,
    repr: bool = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    slots: bool = ...,
    frozen: bool = ...,
    weakref_slot: bool = ...,
    str: bool = ...,
    auto_attribs: bool = ...,
    kw_only: bool = ...,
    cache_hash: bool = ...,
    auto_exc: bool = ...,
    eq: Optional[bool] = ...,
    order: Optional[bool] = ...,
    auto_detect: bool = ...,
    getstate_setstate: Optional[bool] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
    match_args: bool = ...,
) -> _C: ...
@overload
@__dataclass_transform__(field_descriptors=(attrib, field))
def define(
    maybe_cls: None = ...,
    *,
    these: Optional[Dict[str, Any]] = ...,
    repr: bool = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    slots: bool = ...,
    frozen: bool = ...,
    weakref_slot: bool = ...,
    str: bool = ...,
    auto_attribs: bool = ...,
    kw_only: bool = ...,
    cache_hash: bool = ...,
    auto_exc: bool = ...,
    eq: Optional[bool] = ...,
    order: Optional[bool] = ...,
    auto_detect: bool = ...,
    getstate_setstate: Optional[bool] = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
    match_args: bool = ...,
) -> Callable[[_C], _C]: ...

mutable = define
frozen = define  # they differ only in their defaults

def fields(cls: Type[AttrsInstance]) -> Any: ...
def fields_dict(cls: Type[AttrsInstance]) -> Dict[str, Attribute[Any]]: ...
def validate(inst: AttrsInstance) -> None: ...
def resolve_types(
    cls: _C,
    globalns: Optional[Dict[str, Any]] = ...,
    localns: Optional[Dict[str, Any]] = ...,
    attribs: Optional[List[Attribute[Any]]] = ...,
) -> _C: ...

# TODO: add support for returning a proper attrs class from the mypy plugin
# we use Any instead of _CountingAttr so that e.g. `make_class('Foo',
# [attr.ib()])` is valid
def make_class(
    name: str,
    attrs: Union[List[str], Tuple[str, ...], Dict[str, Any]],
    bases: Tuple[type, ...] = ...,
    repr_ns: Optional[str] = ...,
    repr: bool = ...,
    cmp: Optional[_EqOrderType] = ...,
    hash: Optional[bool] = ...,
    init: bool = ...,
    slots: bool = ...,
    frozen: bool = ...,
    weakref_slot: bool = ...,
    str: bool = ...,
    auto_attribs: bool = ...,
    kw_only: bool = ...,
    cache_hash: bool = ...,
    auto_exc: bool = ...,
    eq: Optional[_EqOrderType] = ...,
    order: Optional[_EqOrderType] = ...,
    collect_by_mro: bool = ...,
    on_setattr: Optional[_OnSetAttrArgType] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
) -> type: ...

# _funcs --

# TODO: add support for returning TypedDict from the mypy plugin
# FIXME: asdict/astuple do not honor their factory args. Waiting on one of
# these:
# https://github.com/python/mypy/issues/4236
# https://github.com/python/typing/issues/253
# XXX: remember to fix attrs.asdict/astuple too!
def asdict(
    inst: AttrsInstance,
    recurse: bool = ...,
    filter: Optional[_FilterType[Any]] = ...,
    dict_factory: Type[Mapping[Any, Any]] = ...,
    retain_collection_types: bool = ...,
    value_serializer: Optional[
        Callable[[type, Attribute[Any], Any], Any]
    ] = ...,
    tuple_keys: Optional[bool] = ...,
) -> Dict[str, Any]: ...

# TODO: add support for returning NamedTuple from the mypy plugin
def astuple(
    inst: AttrsInstance,
    recurse: bool = ...,
    filter: Optional[_FilterType[Any]] = ...,
    tuple_factory: Type[Sequence[Any]] = ...,
    retain_collection_types: bool = ...,
) -> Tuple[Any, ...]: ...
def has(cls: type) -> bool: ...
def assoc(inst: _T, **changes: Any) -> _T: ...
def evolve(inst: _T, **changes: Any) -> _T: ...

# _config --

def set_run_validators(run: bool) -> None: ...
def get_run_validators() -> bool: ...

# aliases --

s = attributes = attrs
ib = attr = attrib
dataclass = attrs  # Technically, partial(attrs, auto_attribs=True) ;)