import collections.abc import io import itertools import typing def isoftype(object, type): """Checks if an object is of a certain typing type, including nested types. This function supports simple types (like `int`, `str`), typing types (like `List[int]`, `Tuple[str, int]`, `Dict[str, int]`), and nested typing types (like `List[List[int]]`, `Tuple[List[str], int]`, `Dict[str, List[int]]`). Args: object: The object to check. type: The typing type to check against. Returns: bool: True if the object is of the specified type, False otherwise. Examples: .. highlight:: python .. code-block:: python isoftype(1, int) # True isoftype([1, 2, 3], typing.List[int]) # True isoftype([1, 2, 3], typing.List[str]) # False isoftype([[1, 2], [3, 4]], typing.List[typing.List[int]]) # True """ if type == typing.Any: return True if hasattr(type, "__origin__"): origin = type.__origin__ type_args = typing.get_args(type) if origin is typing.Union: return any(isoftype(object, sub_type) for sub_type in type_args) if not isinstance(object, origin): return False if origin is list or origin is set: return all(isoftype(element, type_args[0]) for element in object) if origin is dict: return all( isoftype(key, type_args[0]) and isoftype(value, type_args[1]) for key, value in object.items() ) if origin is tuple: return all( isoftype(element, type_arg) for element, type_arg in zip(object, type_args) ) return None return isinstance(object, type) # copied from: https://github.com/bojiang/typing_utils/blob/main/typing_utils/__init__.py # liscened under Apache License 2.0 if hasattr(typing, "ForwardRef"): # python3.8 ForwardRef = typing.ForwardRef elif hasattr(typing, "_ForwardRef"): # python3.6 ForwardRef = typing._ForwardRef else: raise NotImplementedError() unknown = None BUILTINS_MAPPING = { typing.List: list, typing.Set: set, typing.Dict: dict, typing.Tuple: tuple, typing.ByteString: bytes, # https://docs.python.org/3/library/typing.html#typing.ByteString typing.Callable: collections.abc.Callable, typing.Sequence: collections.abc.Sequence, type(None): None, } STATIC_SUBTYPE_MAPPING: typing.Dict[type, typing.Type] = { io.TextIOWrapper: typing.TextIO, io.TextIOBase: typing.TextIO, io.StringIO: typing.TextIO, io.BufferedReader: typing.BinaryIO, io.BufferedWriter: typing.BinaryIO, io.BytesIO: typing.BinaryIO, } def optional_all(elements) -> typing.Optional[bool]: if all(elements): return True if all(e is False for e in elements): return False return unknown def optional_any(elements) -> typing.Optional[bool]: if any(elements): return True if any(e is None for e in elements): return unknown return False def _hashable(value): """Determine whether `value` can be hashed.""" try: hash(value) except TypeError: return False return True get_type_hints = typing.get_type_hints GenericClass = type(typing.List) UnionClass = type(typing.Union) Type = typing.Union[None, type, "typing.TypeVar"] OriginType = typing.Union[None, type] TypeArgs = typing.Union[type, typing.AbstractSet[type], typing.Sequence[type]] def _normalize_aliases(type_: Type) -> Type: if isinstance(type_, typing.TypeVar): return type_ assert _hashable(type_), "_normalize_aliases should only be called on element types" if type_ in BUILTINS_MAPPING: return BUILTINS_MAPPING[type_] return type_ def get_origin(type_): """Get the unsubscripted version of a type. This supports generic types, Callable, Tuple, Union, Literal, Final and ClassVar. Return None for unsupported types. Examples: Here are some code examples using `get_origin` from the `typing_utils` module: .. code-block:: python from typing_utils import get_origin # Examples of get_origin usage get_origin(Literal[42]) is Literal # True get_origin(int) is None # True get_origin(ClassVar[int]) is ClassVar # True get_origin(Generic) is Generic # True get_origin(Generic[T]) is Generic # True get_origin(Union[T, int]) is Union # True get_origin(List[Tuple[T, T]][int]) == list # True """ if hasattr(typing, "get_origin"): # python 3.8+ _getter = typing.get_origin ori = _getter(type_) elif hasattr(typing.List, "_special"): # python 3.7 if isinstance(type_, GenericClass) and not type_._special: ori = type_.__origin__ elif hasattr(type_, "_special") and type_._special: ori = type_ elif type_ is typing.Generic: ori = typing.Generic else: ori = None else: # python 3.6 if isinstance(type_, GenericClass): ori = type_.__origin__ if ori is None: ori = type_ elif isinstance(type_, UnionClass): ori = type_.__origin__ elif type_ is typing.Generic: ori = typing.Generic else: ori = None return _normalize_aliases(ori) def get_args(type_) -> typing.Tuple: """Get type arguments with all substitutions performed. For unions, basic simplifications used by Union constructor are performed. Examples: Here are some code examples using `get_args` from the `typing_utils` module: .. code-block:: python from typing_utils import get_args # Examples of get_args usage get_args(Dict[str, int]) == (str, int) # True get_args(int) == () # True get_args(Union[int, Union[T, int], str][int]) == (int, str) # True get_args(Union[int, Tuple[T, int]][str]) == (int, Tuple[str, int]) # True get_args(Callable[[], T][int]) == ([], int) # True """ if hasattr(typing, "get_args"): # python 3.8+ _getter = typing.get_args res = _getter(type_) elif hasattr(typing.List, "_special"): # python 3.7 if ( isinstance(type_, GenericClass) and not type_._special ): # backport for python 3.8 res = type_.__args__ if get_origin(type_) is collections.abc.Callable and res[0] is not Ellipsis: res = (list(res[:-1]), res[-1]) else: res = () else: # python 3.6 if isinstance(type_, (GenericClass, UnionClass)): # backport for python 3.8 res = type_.__args__ if get_origin(type_) is collections.abc.Callable and res[0] is not Ellipsis: res = (list(res[:-1]), res[-1]) else: res = () return () if res is None else res def eval_forward_ref(ref, forward_refs=None): """Eval forward_refs in all cPython versions.""" localns = forward_refs or {} if hasattr(typing, "_eval_type"): # python3.8 & python 3.9 _eval_type = typing._eval_type return _eval_type(ref, globals(), localns) if hasattr(ref, "_eval_type"): # python3.6 _eval_type = ref._eval_type return _eval_type(globals(), localns) raise NotImplementedError() class NormalizedType(typing.NamedTuple): """Normalized type, made it possible to compare, hash between types.""" origin: Type args: typing.Union[tuple, frozenset] = () def __eq__(self, other): if isinstance(other, NormalizedType): if self.origin != other.origin: return False if isinstance(self.args, frozenset) and isinstance(other.args, frozenset): return self.args <= other.args and other.args <= self.args return self.origin == other.origin and self.args == other.args if not self.args: return self.origin == other return False def __hash__(self) -> int: if not self.args: return hash(self.origin) return hash((self.origin, self.args)) def __repr__(self): if not self.args: return f"{self.origin}" return f"{self.origin}[{self.args}])" def _normalize_args(tps: TypeArgs): if isinstance(tps, str): return tps if isinstance(tps, collections.abc.Sequence): return tuple(_normalize_args(type_) for type_ in tps) if isinstance(tps, collections.abc.Set): return frozenset(_normalize_args(type_) for type_ in tps) return normalize(tps) def normalize(type_: Type) -> NormalizedType: """Convert types to NormalizedType instances.""" args = get_args(type_) origin = get_origin(type_) if not origin: return NormalizedType(_normalize_aliases(type_)) origin = _normalize_aliases(origin) if origin is typing.Union: # sort args when the origin is Union args = _normalize_args(frozenset(args)) else: args = _normalize_args(args) return NormalizedType(origin, args) def _is_origin_subtype(left: OriginType, right: OriginType) -> bool: if left is right: return True if ( left is not None and left in STATIC_SUBTYPE_MAPPING and right == STATIC_SUBTYPE_MAPPING[left] ): return True if hasattr(left, "mro"): for parent in left.mro(): if parent == right: return True if isinstance(left, type) and isinstance(right, type): return issubclass(left, right) return left == right NormalizedTypeArgs = typing.Union[ typing.Tuple["NormalizedTypeArgs", ...], typing.FrozenSet[NormalizedType], NormalizedType, ] def _is_origin_subtype_args( left: NormalizedTypeArgs, right: NormalizedTypeArgs, forward_refs: typing.Optional[typing.Mapping[str, type]], ) -> typing.Optional[bool]: if isinstance(left, frozenset): if not isinstance(right, frozenset): return False excluded = left - right if not excluded: # Union[str, int] <> Union[int, str] return True # Union[list, int] <> Union[typing.Sequence, int] return all( any(_is_normal_subtype(e, r, forward_refs) for r in right) for e in excluded ) if isinstance(left, collections.abc.Sequence) and not isinstance( left, NormalizedType ): if not isinstance(right, collections.abc.Sequence) or isinstance( right, NormalizedType ): return False if ( left and left[-1].origin is not Ellipsis and right and right[-1].origin is Ellipsis ): # Tuple[type, type] <> Tuple[type, ...] return all( _is_origin_subtype_args(lft, right[0], forward_refs) for lft in left ) if len(left) != len(right): return False return all( lft is not None and rgt is not None and _is_origin_subtype_args(lft, rgt, forward_refs) for lft, rgt in itertools.zip_longest(left, right) ) assert isinstance(left, NormalizedType) assert isinstance(right, NormalizedType) return _is_normal_subtype(left, right, forward_refs) def _is_normal_subtype( left: NormalizedType, right: NormalizedType, forward_refs: typing.Optional[typing.Mapping[str, type]], ) -> typing.Optional[bool]: if isinstance(left.origin, ForwardRef): left = normalize(eval_forward_ref(left.origin, forward_refs=forward_refs)) if isinstance(right.origin, ForwardRef): right = normalize(eval_forward_ref(right.origin, forward_refs=forward_refs)) # Any if right.origin is typing.Any: return True # Union if right.origin is typing.Union and left.origin is typing.Union: return _is_origin_subtype_args(left.args, right.args, forward_refs) if right.origin is typing.Union: return optional_any( _is_normal_subtype(left, a, forward_refs) for a in right.args ) if left.origin is typing.Union: return optional_all( _is_normal_subtype(a, right, forward_refs) for a in left.args ) # TypeVar if isinstance(left.origin, typing.TypeVar) and isinstance( right.origin, typing.TypeVar ): if left.origin is right.origin: return True left_bound = getattr(left.origin, "__bound__", None) right_bound = getattr(right.origin, "__bound__", None) if right_bound is None or left_bound is None: return unknown return _is_normal_subtype( normalize(left_bound), normalize(right_bound), forward_refs ) if isinstance(right.origin, typing.TypeVar): return unknown if isinstance(left.origin, typing.TypeVar): left_bound = getattr(left.origin, "__bound__", None) if left_bound is None: return unknown return _is_normal_subtype(normalize(left_bound), right, forward_refs) if not left.args and not right.args: return _is_origin_subtype(left.origin, right.origin) if not right.args: return _is_origin_subtype(left.origin, right.origin) if _is_origin_subtype(left.origin, right.origin): return _is_origin_subtype_args(left.args, right.args, forward_refs) return False def issubtype( left: Type, right: Type, forward_refs: typing.Optional[dict] = None, ) -> typing.Optional[bool]: """Check that the left argument is a subtype of the right. For unions, check if the type arguments of the left is a subset of the right. Also works for nested types including ForwardRefs. Examples: Here are some code examples using `issubtype` from the `typing_utils` module: .. code-block:: python from typing_utils import issubtype # Examples of issubtype checks issubtype(typing.List, typing.Any) # True issubtype(list, list) # True issubtype(list, typing.List) # True issubtype(list, typing.Sequence) # True issubtype(typing.List[int], list) # True issubtype(typing.List[typing.List], list) # True issubtype(list, typing.List[int]) # False issubtype(list, typing.Union[typing.Tuple, typing.Set]) # False issubtype(typing.List[typing.List], typing.List[typing.Sequence]) # True # Example with custom JSON type JSON = typing.Union[ int, float, bool, str, None, typing.Sequence["JSON"], typing.Mapping[str, "JSON"] ] issubtype(str, JSON, forward_refs={'JSON': JSON}) # True issubtype(typing.Dict[str, str], JSON, forward_refs={'JSON': JSON}) # True issubtype(typing.Dict[str, bytes], JSON, forward_refs={'JSON': JSON}) # False """ return _is_normal_subtype(normalize(left), normalize(right), forward_refs)