Datasets:
File size: 2,638 Bytes
d8a7ddd | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 | """
Tests type variable variance inference for generic protocols.
"""
# Specification: https://typing.readthedocs.io/en/latest/spec/protocol.html#generic-protocols
from typing import Protocol, TypeVar
from typing_extensions import ParamSpec
T1 = TypeVar("T1")
T2 = TypeVar("T2", bound=int)
T3 = TypeVar("T3", bytes, str)
T1_co = TypeVar("T1_co", covariant=True)
T1_contra = TypeVar("T1_contra", contravariant=True)
P = ParamSpec("P", contravariant=True)
R = TypeVar("R", covariant=True)
# > Type checkers will warn if the inferred variance is different from the
# > declared variance.
class AnotherBox(Protocol[T1]): # E: T should be covariant
def content(self) -> T1:
...
class Protocol1(Protocol[T1, T2, T3]): # OK
def m1(self, p0: T1, p1: T2, p2: T3) -> T1 | T2:
...
def m2(self) -> T1:
...
def m3(self) -> T2:
...
def m4(self) -> T3:
...
class Protocol2(Protocol[T1, T2, T3]): # E: T3 should be contravariant
def m1(self, p0: T1, p1: T2, p2: T3) -> T1:
...
def m2(self) -> T1:
...
def m3(self) -> T2:
...
class Protocol3(Protocol[T1_co]):
def m1(self) -> None:
pass
class Protocol4(Protocol[T1]): # E: T1 should be contravariant
def m1(self, p0: T1) -> None:
...
class Protocol5(Protocol[T1_co]): # E[covariant_in_input+]
def m1(self, p0: T1_co) -> None: # E[covariant_in_input+]
...
class Protocol6(Protocol[T1]): # E: T1 should be covariant
def m1(self) -> T1:
...
class Protocol7(Protocol[T1_contra]): # E[contravariant_in_output+]
def m1(self) -> T1_contra: # E[contravariant_in_output+]
...
class Protocol8(Protocol[T1]): # OK
def m1(self) -> T1:
...
def m2(self, p1: T1) -> None:
pass
class Callback(Protocol[P, R]): # OK
def __call__(self, *args: P.args, **kwargs: P.kwargs) -> R:
...
class Protocol9(Protocol[T1_co]): # OK
@property
def prop1(self) -> T1_co:
...
class Protocol10(Protocol[T1_co]): # OK
def m1(self) -> type[T1_co]:
...
class Protocol11(Protocol[T1]): # OK
x: T1 | None
class Protocol12(Protocol[T1]): # E: T1 should be covariant
# __init__ method is exempt from variance calculations.
def __init__(self, x: T1) -> None:
...
class Protocol13(Protocol[T1_contra]): # OK
def m1(self: "Protocol13[T1_contra]", x: T1_contra) -> None:
...
@classmethod
def m2(cls: "type[Protocol13[T1_contra]]") -> None:
...
class Protocol14(Protocol[T1]): # OK
def m1(self) -> list[T1]:
...
|