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"""Defines experimental API for runtime inspection of types defined
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in the standard "typing" module.
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Example usage::
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from typing_inspect import is_generic_type
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"""
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# NOTE: This module must support Python 2.7 in addition to Python 3.x
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import sys
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from mypy_extensions import _TypedDictMeta
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NEW_TYPING = sys.version_info[:3] >= (3, 7, 0) # PEP 560
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if NEW_TYPING:
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import collections.abc
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WITH_LITERAL = True
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WITH_CLASSVAR = True
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LEGACY_TYPING = False
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if NEW_TYPING:
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from typing import (
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Generic, Callable, Union, TypeVar, ClassVar, Tuple, _GenericAlias, ForwardRef
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)
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from typing_extensions import Literal
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else:
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from typing import (
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Callable, CallableMeta, Union, Tuple, TupleMeta, TypeVar, GenericMeta, _ForwardRef
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)
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try:
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from typing import _Union, _ClassVar
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except ImportError:
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# support for very old typing module <=3.5.3
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_Union = type(Union)
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WITH_CLASSVAR = False
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LEGACY_TYPING = True
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try: # python 3.6
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from typing_extensions import _Literal
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except ImportError: # python 2.7
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try:
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from typing import _Literal
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except ImportError:
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WITH_LITERAL = False
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def _gorg(cls):
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"""This function exists for compatibility with old typing versions."""
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assert isinstance(cls, GenericMeta)
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if hasattr(cls, '_gorg'):
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return cls._gorg
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while cls.__origin__ is not None:
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cls = cls.__origin__
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return cls
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def is_generic_type(tp):
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"""Test if the given type is a generic type. This includes Generic itself, but
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excludes special typing constructs such as Union, Tuple, Callable, ClassVar.
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Examples::
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is_generic_type(int) == False
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is_generic_type(Union[int, str]) == False
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is_generic_type(Union[int, T]) == False
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is_generic_type(ClassVar[List[int]]) == False
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is_generic_type(Callable[..., T]) == False
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is_generic_type(Generic) == True
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is_generic_type(Generic[T]) == True
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is_generic_type(Iterable[int]) == True
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is_generic_type(Mapping) == True
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is_generic_type(MutableMapping[T, List[int]]) == True
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is_generic_type(Sequence[Union[str, bytes]]) == True
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"""
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if NEW_TYPING:
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return (isinstance(tp, type) and issubclass(tp, Generic) or
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isinstance(tp, _GenericAlias) and
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tp.__origin__ not in (Union, tuple, ClassVar, collections.abc.Callable))
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return (isinstance(tp, GenericMeta) and not
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isinstance(tp, (CallableMeta, TupleMeta)))
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def is_callable_type(tp):
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"""Test if the type is a generic callable type, including subclasses
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excluding non-generic types and callables.
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Examples::
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is_callable_type(int) == False
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is_callable_type(type) == False
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is_callable_type(Callable) == True
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is_callable_type(Callable[..., int]) == True
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is_callable_type(Callable[[int, int], Iterable[str]]) == True
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class MyClass(Callable[[int], int]):
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...
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is_callable_type(MyClass) == True
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For more general tests use callable(), for more precise test
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(excluding subclasses) use::
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get_origin(tp) is collections.abc.Callable # Callable prior to Python 3.7
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"""
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if NEW_TYPING:
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return (tp is Callable or isinstance(tp, _GenericAlias) and
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tp.__origin__ is collections.abc.Callable or
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isinstance(tp, type) and issubclass(tp, Generic) and
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issubclass(tp, collections.abc.Callable))
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return type(tp) is CallableMeta
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def is_tuple_type(tp):
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"""Test if the type is a generic tuple type, including subclasses excluding
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non-generic classes.
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Examples::
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is_tuple_type(int) == False
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is_tuple_type(tuple) == False
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is_tuple_type(Tuple) == True
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is_tuple_type(Tuple[str, int]) == True
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class MyClass(Tuple[str, int]):
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...
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is_tuple_type(MyClass) == True
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For more general tests use issubclass(..., tuple), for more precise test
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(excluding subclasses) use::
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get_origin(tp) is tuple # Tuple prior to Python 3.7
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"""
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if NEW_TYPING:
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return (tp is Tuple or isinstance(tp, _GenericAlias) and
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tp.__origin__ is tuple or
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isinstance(tp, type) and issubclass(tp, Generic) and
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issubclass(tp, tuple))
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return type(tp) is TupleMeta
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def is_optional_type(tp):
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"""Test if the type is type(None), or is a direct union with it, such as Optional[T].
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NOTE: this method inspects nested `Union` arguments but not `TypeVar` definition
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bounds and constraints. So it will return `False` if
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- `tp` is a `TypeVar` bound, or constrained to, an optional type
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- `tp` is a `Union` to a `TypeVar` bound or constrained to an optional type,
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- `tp` refers to a *nested* `Union` containing an optional type or one of the above.
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Users wishing to check for optionality in types relying on type variables might wish
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to use this method in combination with `get_constraints` and `get_bound`
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"""
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if tp is type(None): # noqa
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return True
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elif is_union_type(tp):
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return any(is_optional_type(tt) for tt in get_args(tp, evaluate=True))
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else:
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return False
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def is_union_type(tp):
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"""Test if the type is a union type. Examples::
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is_union_type(int) == False
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is_union_type(Union) == True
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is_union_type(Union[int, int]) == False
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is_union_type(Union[T, int]) == True
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"""
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if NEW_TYPING:
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return (tp is Union or
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isinstance(tp, _GenericAlias) and tp.__origin__ is Union)
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return type(tp) is _Union
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def is_literal_type(tp):
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if NEW_TYPING:
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return (tp is Literal or
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isinstance(tp, _GenericAlias) and tp.__origin__ is Literal)
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return WITH_LITERAL and type(tp) is _Literal
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def is_typevar(tp):
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"""Test if the type represents a type variable. Examples::
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is_typevar(int) == False
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is_typevar(T) == True
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is_typevar(Union[T, int]) == False
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"""
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return type(tp) is TypeVar
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def is_classvar(tp):
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"""Test if the type represents a class variable. Examples::
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is_classvar(int) == False
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is_classvar(ClassVar) == True
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is_classvar(ClassVar[int]) == True
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is_classvar(ClassVar[List[T]]) == True
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"""
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if NEW_TYPING:
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return (tp is ClassVar or
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isinstance(tp, _GenericAlias) and tp.__origin__ is ClassVar)
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elif WITH_CLASSVAR:
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return type(tp) is _ClassVar
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else:
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return False
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def is_new_type(tp):
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"""Tests if the type represents a distinct type. Examples::
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is_new_type(int) == False
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is_new_type(NewType('Age', int)) == True
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is_new_type(NewType('Scores', List[Dict[str, float]])) == True
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"""
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return getattr(tp, '__supertype__', None) is not None
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def is_forward_ref(tp):
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"""Tests if the type is a :class:`typing.ForwardRef`. Examples::
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u = Union["Milk", Way]
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args = get_args(u)
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is_forward_ref(args[0]) == True
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is_forward_ref(args[1]) == False
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"""
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if not NEW_TYPING:
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return isinstance(tp, _ForwardRef)
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return isinstance(tp, ForwardRef)
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def get_last_origin(tp):
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"""Get the last base of (multiply) subscripted type. Supports generic types,
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Union, Callable, and Tuple. Returns None for unsupported types.
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Examples::
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get_last_origin(int) == None
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get_last_origin(ClassVar[int]) == None
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get_last_origin(Generic[T]) == Generic
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get_last_origin(Union[T, int][str]) == Union[T, int]
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get_last_origin(List[Tuple[T, T]][int]) == List[Tuple[T, T]]
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get_last_origin(List) == List
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"""
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if NEW_TYPING:
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raise ValueError('This function is only supported in Python 3.6,'
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' use get_origin instead')
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sentinel = object()
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origin = getattr(tp, '__origin__', sentinel)
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if origin is sentinel:
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return None
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if origin is None:
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return tp
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return origin
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def get_origin(tp):
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"""Get the unsubscripted version of a type. Supports generic types, Union,
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Callable, and Tuple. Returns None for unsupported types. Examples::
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get_origin(int) == None
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get_origin(ClassVar[int]) == None
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get_origin(Generic) == Generic
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get_origin(Generic[T]) == Generic
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get_origin(Union[T, int]) == Union
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get_origin(List[Tuple[T, T]][int]) == list # List prior to Python 3.7
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"""
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if NEW_TYPING:
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if isinstance(tp, _GenericAlias):
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return tp.__origin__ if tp.__origin__ is not ClassVar else None
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if tp is Generic:
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return Generic
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return None
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if isinstance(tp, GenericMeta):
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return _gorg(tp)
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if is_union_type(tp):
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return Union
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if is_tuple_type(tp):
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return Tuple
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return None
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def get_parameters(tp):
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"""Return type parameters of a parameterizable type as a tuple
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in lexicographic order. Parameterizable types are generic types,
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unions, tuple types and callable types. Examples::
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get_parameters(int) == ()
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get_parameters(Generic) == ()
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get_parameters(Union) == ()
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get_parameters(List[int]) == ()
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get_parameters(Generic[T]) == (T,)
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get_parameters(Tuple[List[T], List[S_co]]) == (T, S_co)
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get_parameters(Union[S_co, Tuple[T, T]][int, U]) == (U,)
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get_parameters(Mapping[T, Tuple[S_co, T]]) == (T, S_co)
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"""
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if LEGACY_TYPING:
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# python <= 3.5.2
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if is_union_type(tp):
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params = []
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for arg in (tp.__union_params__ if tp.__union_params__ is not None else ()):
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params += get_parameters(arg)
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return tuple(params)
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elif is_tuple_type(tp):
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params = []
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for arg in (tp.__tuple_params__ if tp.__tuple_params__ is not None else ()):
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params += get_parameters(arg)
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return tuple(params)
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elif is_generic_type(tp):
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params = []
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base_params = tp.__parameters__
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if base_params is None:
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return ()
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for bp_ in base_params:
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for bp in (get_args(bp_) if is_tuple_type(bp_) else (bp_,)):
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if _has_type_var(bp) and not isinstance(bp, TypeVar):
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raise TypeError(
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"Cannot inherit from a generic class "
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"parameterized with "
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"non-type-variable %s" % bp)
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if params is None:
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params = []
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if bp not in params:
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params.append(bp)
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if params is not None:
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return tuple(params)
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else:
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return ()
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else:
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return ()
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elif NEW_TYPING:
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if (isinstance(tp, _GenericAlias) or
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isinstance(tp, type) and issubclass(tp, Generic) and
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tp is not Generic):
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return tp.__parameters__
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else:
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return ()
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elif (
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is_generic_type(tp) or is_union_type(tp) or
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is_callable_type(tp) or is_tuple_type(tp)
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):
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return tp.__parameters__ if tp.__parameters__ is not None else ()
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else:
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return ()
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342 |
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def get_last_args(tp):
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"""Get last arguments of (multiply) subscripted type.
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Parameters for Callable are flattened. Examples::
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|
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get_last_args(int) == ()
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get_last_args(Union) == ()
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get_last_args(ClassVar[int]) == (int,)
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get_last_args(Union[T, int]) == (T, int)
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get_last_args(Iterable[Tuple[T, S]][int, T]) == (int, T)
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get_last_args(Callable[[T], int]) == (T, int)
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get_last_args(Callable[[], int]) == (int,)
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"""
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356 |
if NEW_TYPING:
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357 |
raise ValueError('This function is only supported in Python 3.6,'
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358 |
' use get_args instead')
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359 |
elif is_classvar(tp):
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return (tp.__type__,) if tp.__type__ is not None else ()
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361 |
elif is_generic_type(tp):
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try:
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363 |
if tp.__args__ is not None and len(tp.__args__) > 0:
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364 |
return tp.__args__
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365 |
except AttributeError:
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366 |
# python 3.5.1
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367 |
pass
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368 |
return tp.__parameters__ if tp.__parameters__ is not None else ()
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369 |
elif is_union_type(tp):
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try:
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371 |
return tp.__args__ if tp.__args__ is not None else ()
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372 |
except AttributeError:
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373 |
# python 3.5.2
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374 |
return tp.__union_params__ if tp.__union_params__ is not None else ()
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375 |
elif is_callable_type(tp):
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376 |
return tp.__args__ if tp.__args__ is not None else ()
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377 |
elif is_tuple_type(tp):
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try:
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return tp.__args__ if tp.__args__ is not None else ()
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380 |
except AttributeError:
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381 |
# python 3.5.2
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return tp.__tuple_params__ if tp.__tuple_params__ is not None else ()
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383 |
else:
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384 |
return ()
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|
385 |
|
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386 |
|
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387 |
def _eval_args(args):
|
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388 |
"""Internal helper for get_args."""
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res = []
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390 |
for arg in args:
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391 |
if not isinstance(arg, tuple):
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res.append(arg)
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393 |
elif is_callable_type(arg[0]):
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394 |
callable_args = _eval_args(arg[1:])
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395 |
if len(arg) == 2:
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res.append(Callable[[], callable_args[0]])
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397 |
elif arg[1] is Ellipsis:
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398 |
res.append(Callable[..., callable_args[1]])
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399 |
else:
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400 |
res.append(Callable[list(callable_args[:-1]), callable_args[-1]])
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401 |
else:
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402 |
res.append(type(arg[0]).__getitem__(arg[0], _eval_args(arg[1:])))
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403 |
return tuple(res)
|
|
404 |
|
|
405 |
|
|
406 |
def get_args(tp, evaluate=None):
|
|
407 |
"""Get type arguments with all substitutions performed. For unions,
|
|
408 |
basic simplifications used by Union constructor are performed.
|
|
409 |
On versions prior to 3.7 if `evaluate` is False (default),
|
|
410 |
report result as nested tuple, this matches
|
|
411 |
the internal representation of types. If `evaluate` is True
|
|
412 |
(or if Python version is 3.7 or greater), then all
|
|
413 |
type parameters are applied (this could be time and memory expensive).
|
|
414 |
Examples::
|
|
415 |
|
|
416 |
get_args(int) == ()
|
|
417 |
get_args(Union[int, Union[T, int], str][int]) == (int, str)
|
|
418 |
get_args(Union[int, Tuple[T, int]][str]) == (int, (Tuple, str, int))
|
|
419 |
|
|
420 |
get_args(Union[int, Tuple[T, int]][str], evaluate=True) == \
|
|
421 |
(int, Tuple[str, int])
|
|
422 |
get_args(Dict[int, Tuple[T, T]][Optional[int]], evaluate=True) == \
|
|
423 |
(int, Tuple[Optional[int], Optional[int]])
|
|
424 |
get_args(Callable[[], T][int], evaluate=True) == ([], int,)
|
|
425 |
"""
|
|
426 |
if NEW_TYPING:
|
|
427 |
if evaluate is not None and not evaluate:
|
|
428 |
raise ValueError('evaluate can only be True in Python >= 3.7')
|
|
429 |
if isinstance(tp, _GenericAlias):
|
|
430 |
res = tp.__args__
|
|
431 |
if get_origin(tp) is collections.abc.Callable and res[0] is not Ellipsis:
|
|
432 |
res = (list(res[:-1]), res[-1])
|
|
433 |
return res
|
|
434 |
return ()
|
|
435 |
if is_classvar(tp):
|
|
436 |
return (tp.__type__,) if tp.__type__ is not None else ()
|
|
437 |
if is_literal_type(tp):
|
|
438 |
return tp.__values__ or ()
|
|
439 |
if (
|
|
440 |
is_generic_type(tp) or is_union_type(tp) or
|
|
441 |
is_callable_type(tp) or is_tuple_type(tp)
|
|
442 |
):
|
|
443 |
try:
|
|
444 |
tree = tp._subs_tree()
|
|
445 |
except AttributeError:
|
|
446 |
# Old python typing module <= 3.5.3
|
|
447 |
if is_union_type(tp):
|
|
448 |
# backport of union's subs_tree
|
|
449 |
tree = _union_subs_tree(tp)
|
|
450 |
elif is_generic_type(tp):
|
|
451 |
# backport of genericmeta's subs_tree
|
|
452 |
tree = _generic_subs_tree(tp)
|
|
453 |
elif is_tuple_type(tp):
|
|
454 |
# ad-hoc (inspired by union)
|
|
455 |
tree = _tuple_subs_tree(tp)
|
|
456 |
else:
|
|
457 |
# tree = _subs_tree(tp)
|
|
458 |
return ()
|
|
459 |
|
|
460 |
if isinstance(tree, tuple) and len(tree) > 1:
|
|
461 |
if not evaluate:
|
|
462 |
return tree[1:]
|
|
463 |
res = _eval_args(tree[1:])
|
|
464 |
if get_origin(tp) is Callable and res[0] is not Ellipsis:
|
|
465 |
res = (list(res[:-1]), res[-1])
|
|
466 |
return res
|
|
467 |
|
|
468 |
return ()
|
|
469 |
|
|
470 |
|
|
471 |
def get_bound(tp):
|
|
472 |
"""Return the type bound to a `TypeVar` if any.
|
|
473 |
|
|
474 |
It the type is not a `TypeVar`, a `TypeError` is raised.
|
|
475 |
Examples::
|
|
476 |
|
|
477 |
get_bound(TypeVar('T')) == None
|
|
478 |
get_bound(TypeVar('T', bound=int)) == int
|
|
479 |
"""
|
|
480 |
|
|
481 |
if is_typevar(tp):
|
|
482 |
return getattr(tp, '__bound__', None)
|
|
483 |
else:
|
|
484 |
raise TypeError("type is not a `TypeVar`: " + str(tp))
|
|
485 |
|
|
486 |
|
|
487 |
def get_constraints(tp):
|
|
488 |
"""Returns the constraints of a `TypeVar` if any.
|
|
489 |
|
|
490 |
It the type is not a `TypeVar`, a `TypeError` is raised
|
|
491 |
Examples::
|
|
492 |
|
|
493 |
get_constraints(TypeVar('T')) == ()
|
|
494 |
get_constraints(TypeVar('T', int, str)) == (int, str)
|
|
495 |
"""
|
|
496 |
|
|
497 |
if is_typevar(tp):
|
|
498 |
return getattr(tp, '__constraints__', ())
|
|
499 |
else:
|
|
500 |
raise TypeError("type is not a `TypeVar`: " + str(tp))
|
|
501 |
|
|
502 |
|
|
503 |
def get_generic_type(obj):
|
|
504 |
"""Get the generic type of an object if possible, or runtime class otherwise.
|
|
505 |
Examples::
|
|
506 |
|
|
507 |
class Node(Generic[T]):
|
|
508 |
...
|
|
509 |
type(Node[int]()) == Node
|
|
510 |
get_generic_type(Node[int]()) == Node[int]
|
|
511 |
get_generic_type(Node[T]()) == Node[T]
|
|
512 |
get_generic_type(1) == int
|
|
513 |
"""
|
|
514 |
|
|
515 |
gen_type = getattr(obj, '__orig_class__', None)
|
|
516 |
return gen_type if gen_type is not None else type(obj)
|
|
517 |
|
|
518 |
|
|
519 |
def get_generic_bases(tp):
|
|
520 |
"""Get generic base types of a type or empty tuple if not possible.
|
|
521 |
Example::
|
|
522 |
|
|
523 |
class MyClass(List[int], Mapping[str, List[int]]):
|
|
524 |
...
|
|
525 |
MyClass.__bases__ == (List, Mapping)
|
|
526 |
get_generic_bases(MyClass) == (List[int], Mapping[str, List[int]])
|
|
527 |
"""
|
|
528 |
if LEGACY_TYPING:
|
|
529 |
return tuple(t for t in tp.__bases__ if isinstance(t, GenericMeta))
|
|
530 |
else:
|
|
531 |
return getattr(tp, '__orig_bases__', ())
|
|
532 |
|
|
533 |
|
|
534 |
def typed_dict_keys(td):
|
|
535 |
"""If td is a TypedDict class, return a dictionary mapping the typed keys to types.
|
|
536 |
Otherwise, return None. Examples::
|
|
537 |
|
|
538 |
class TD(TypedDict):
|
|
539 |
x: int
|
|
540 |
y: int
|
|
541 |
class Other(dict):
|
|
542 |
x: int
|
|
543 |
y: int
|
|
544 |
|
|
545 |
typed_dict_keys(TD) == {'x': int, 'y': int}
|
|
546 |
typed_dict_keys(dict) == None
|
|
547 |
typed_dict_keys(Other) == None
|
|
548 |
"""
|
|
549 |
if isinstance(td, _TypedDictMeta):
|
|
550 |
return td.__annotations__.copy()
|
|
551 |
return None
|
|
552 |
|
|
553 |
|
|
554 |
def get_forward_arg(fr):
|
|
555 |
"""
|
|
556 |
If fr is a ForwardRef, return the string representation of the forward reference.
|
|
557 |
Otherwise return None. Examples::
|
|
558 |
|
|
559 |
tp = List["FRef"]
|
|
560 |
fr = get_args(tp)[0]
|
|
561 |
get_forward_arg(fr) == "FRef"
|
|
562 |
get_forward_arg(tp) == None
|
|
563 |
"""
|
|
564 |
return fr.__forward_arg__ if is_forward_ref(fr) else None
|
|
565 |
|
|
566 |
|
|
567 |
# A few functions backported and adapted for the LEGACY_TYPING context, and used above
|
|
568 |
|
|
569 |
def _replace_arg(arg, tvars, args):
|
|
570 |
"""backport of _replace_arg"""
|
|
571 |
if tvars is None:
|
|
572 |
tvars = []
|
|
573 |
# if hasattr(arg, '_subs_tree') and isinstance(arg, (GenericMeta, _TypingBase)):
|
|
574 |
# return arg._subs_tree(tvars, args)
|
|
575 |
if is_union_type(arg):
|
|
576 |
return _union_subs_tree(arg, tvars, args)
|
|
577 |
if is_tuple_type(arg):
|
|
578 |
return _tuple_subs_tree(arg, tvars, args)
|
|
579 |
if is_generic_type(arg):
|
|
580 |
return _generic_subs_tree(arg, tvars, args)
|
|
581 |
if isinstance(arg, TypeVar):
|
|
582 |
for i, tvar in enumerate(tvars):
|
|
583 |
if arg == tvar:
|
|
584 |
return args[i]
|
|
585 |
return arg
|
|
586 |
|
|
587 |
|
|
588 |
def _remove_dups_flatten(parameters):
|
|
589 |
"""backport of _remove_dups_flatten"""
|
|
590 |
|
|
591 |
# Flatten out Union[Union[...], ...].
|
|
592 |
params = []
|
|
593 |
for p in parameters:
|
|
594 |
if isinstance(p, _Union): # and p.__origin__ is Union:
|
|
595 |
params.extend(p.__union_params__) # p.__args__)
|
|
596 |
elif isinstance(p, tuple) and len(p) > 0 and p[0] is Union:
|
|
597 |
params.extend(p[1:])
|
|
598 |
else:
|
|
599 |
params.append(p)
|
|
600 |
# Weed out strict duplicates, preserving the first of each occurrence.
|
|
601 |
all_params = set(params)
|
|
602 |
if len(all_params) < len(params):
|
|
603 |
new_params = []
|
|
604 |
for t in params:
|
|
605 |
if t in all_params:
|
|
606 |
new_params.append(t)
|
|
607 |
all_params.remove(t)
|
|
608 |
params = new_params
|
|
609 |
assert not all_params, all_params
|
|
610 |
# Weed out subclasses.
|
|
611 |
# E.g. Union[int, Employee, Manager] == Union[int, Employee].
|
|
612 |
# If object is present it will be sole survivor among proper classes.
|
|
613 |
# Never discard type variables.
|
|
614 |
# (In particular, Union[str, AnyStr] != AnyStr.)
|
|
615 |
all_params = set(params)
|
|
616 |
for t1 in params:
|
|
617 |
if not isinstance(t1, type):
|
|
618 |
continue
|
|
619 |
if any(isinstance(t2, type) and issubclass(t1, t2)
|
|
620 |
for t2 in all_params - {t1}
|
|
621 |
if (not (isinstance(t2, GenericMeta) and
|
|
622 |
get_origin(t2) is not None) and
|
|
623 |
not isinstance(t2, TypeVar))):
|
|
624 |
all_params.remove(t1)
|
|
625 |
return tuple(t for t in params if t in all_params)
|
|
626 |
|
|
627 |
|
|
628 |
def _subs_tree(cls, tvars=None, args=None):
|
|
629 |
"""backport of typing._subs_tree, adapted for legacy versions """
|
|
630 |
def _get_origin(cls):
|
|
631 |
try:
|
|
632 |
return cls.__origin__
|
|
633 |
except AttributeError:
|
|
634 |
return None
|
|
635 |
|
|
636 |
current = _get_origin(cls)
|
|
637 |
if current is None:
|
|
638 |
if not is_union_type(cls) and not is_tuple_type(cls):
|
|
639 |
return cls
|
|
640 |
|
|
641 |
# Make of chain of origins (i.e. cls -> cls.__origin__)
|
|
642 |
orig_chain = []
|
|
643 |
while _get_origin(current) is not None:
|
|
644 |
orig_chain.append(current)
|
|
645 |
current = _get_origin(current)
|
|
646 |
|
|
647 |
# Replace type variables in __args__ if asked ...
|
|
648 |
tree_args = []
|
|
649 |
|
|
650 |
def _get_args(cls):
|
|
651 |
if is_union_type(cls):
|
|
652 |
cls_args = cls.__union_params__
|
|
653 |
elif is_tuple_type(cls):
|
|
654 |
cls_args = cls.__tuple_params__
|
|
655 |
else:
|
|
656 |
try:
|
|
657 |
cls_args = cls.__args__
|
|
658 |
except AttributeError:
|
|
659 |
cls_args = ()
|
|
660 |
return cls_args if cls_args is not None else ()
|
|
661 |
|
|
662 |
for arg in _get_args(cls):
|
|
663 |
tree_args.append(_replace_arg(arg, tvars, args))
|
|
664 |
# ... then continue replacing down the origin chain.
|
|
665 |
for ocls in orig_chain:
|
|
666 |
new_tree_args = []
|
|
667 |
for arg in _get_args(ocls):
|
|
668 |
new_tree_args.append(_replace_arg(arg, get_parameters(ocls), tree_args))
|
|
669 |
tree_args = new_tree_args
|
|
670 |
return tree_args
|
|
671 |
|
|
672 |
|
|
673 |
def _union_subs_tree(tp, tvars=None, args=None):
|
|
674 |
""" backport of Union._subs_tree """
|
|
675 |
if tp is Union:
|
|
676 |
return Union # Nothing to substitute
|
|
677 |
tree_args = _subs_tree(tp, tvars, args)
|
|
678 |
# tree_args = tp.__union_params__ if tp.__union_params__ is not None else ()
|
|
679 |
tree_args = _remove_dups_flatten(tree_args)
|
|
680 |
if len(tree_args) == 1:
|
|
681 |
return tree_args[0] # Union of a single type is that type
|
|
682 |
return (Union,) + tree_args
|
|
683 |
|
|
684 |
|
|
685 |
def _generic_subs_tree(tp, tvars=None, args=None):
|
|
686 |
""" backport of GenericMeta._subs_tree """
|
|
687 |
if tp.__origin__ is None:
|
|
688 |
return tp
|
|
689 |
tree_args = _subs_tree(tp, tvars, args)
|
|
690 |
return (_gorg(tp),) + tuple(tree_args)
|
|
691 |
|
|
692 |
|
|
693 |
def _tuple_subs_tree(tp, tvars=None, args=None):
|
|
694 |
""" ad-hoc function (inspired by union) for legacy typing """
|
|
695 |
if tp is Tuple:
|
|
696 |
return Tuple # Nothing to substitute
|
|
697 |
tree_args = _subs_tree(tp, tvars, args)
|
|
698 |
return (Tuple,) + tuple(tree_args)
|
|
699 |
|
|
700 |
|
|
701 |
def _has_type_var(t):
|
|
702 |
if t is None:
|
|
703 |
return False
|
|
704 |
elif is_union_type(t):
|
|
705 |
return _union_has_type_var(t)
|
|
706 |
elif is_tuple_type(t):
|
|
707 |
return _tuple_has_type_var(t)
|
|
708 |
elif is_generic_type(t):
|
|
709 |
return _generic_has_type_var(t)
|
|
710 |
elif is_callable_type(t):
|
|
711 |
return _callable_has_type_var(t)
|
|
712 |
else:
|
|
713 |
return False
|
|
714 |
|
|
715 |
|
|
716 |
def _union_has_type_var(tp):
|
|
717 |
if tp.__union_params__:
|
|
718 |
for t in tp.__union_params__:
|
|
719 |
if _has_type_var(t):
|
|
720 |
return True
|
|
721 |
return False
|
|
722 |
|
|
723 |
|
|
724 |
def _tuple_has_type_var(tp):
|
|
725 |
if tp.__tuple_params__:
|
|
726 |
for t in tp.__tuple_params__:
|
|
727 |
if _has_type_var(t):
|
|
728 |
return True
|
|
729 |
return False
|
|
730 |
|
|
731 |
|
|
732 |
def _callable_has_type_var(tp):
|
|
733 |
if tp.__args__:
|
|
734 |
for t in tp.__args__:
|
|
735 |
if _has_type_var(t):
|
|
736 |
return True
|
|
737 |
return _has_type_var(tp.__result__)
|
|
738 |
|
|
739 |
|
|
740 |
def _generic_has_type_var(tp):
|
|
741 |
if tp.__parameters__:
|
|
742 |
for t in tp.__parameters__:
|
|
743 |
if _has_type_var(t):
|
|
744 |
return True
|
|
745 |
return False
|