Fixed some type annotation inconsistencies

* AsyncBackend.getaddrinfo() may return 4-tuple socket addresses for IPv6, unlike anyio.getaddrinfo()
* The CancelScope facade for trio may in fact return a bool
* Removed type ignore comments for getaddrinfo() and getnameinfo() in the trio backend

src/anyio/_backends/_asyncio.py

@@ -64,7 +64,7 @@
     EndOfStream,
     WouldBlock,
 )
-from .._core._sockets import GetAddrInfoReturnType, convert_ipv6_sockaddr
+from .._core._sockets import convert_ipv6_sockaddr
 from .._core._streams import create_memory_object_stream
 from .._core._synchronization import CapacityLimiter as BaseCapacityLimiter
 from .._core._synchronization import Event as BaseEvent
@@ -2211,11 +2211,18 @@ async def getaddrinfo(
         type: int | SocketKind = 0,
         proto: int = 0,
         flags: int = 0,
-    ) -> GetAddrInfoReturnType:
-        result = await get_running_loop().getaddrinfo(
+    ) -> list[
+        tuple[
+            AddressFamily,
+            SocketKind,
+            int,
+            str,
+            tuple[str, int] | tuple[str, int, int, int],
+        ]
+    ]:
+        return await get_running_loop().getaddrinfo(
             host, port, family=family, type=type, proto=proto, flags=flags
         )
-        return cast(GetAddrInfoReturnType, result)
 
     @classmethod
     async def getnameinfo(

src/anyio/_backends/_trio.py

@@ -51,7 +51,7 @@
     ClosedResourceError,
     EndOfStream,
 )
-from .._core._sockets import GetAddrInfoReturnType, convert_ipv6_sockaddr
+from .._core._sockets import convert_ipv6_sockaddr
 from .._core._streams import create_memory_object_stream
 from .._core._synchronization import CapacityLimiter as BaseCapacityLimiter
 from .._core._synchronization import Event as BaseEvent
@@ -96,8 +96,11 @@ def __exit__(
         exc_type: type[BaseException] | None,
         exc_val: BaseException | None,
         exc_tb: TracebackType | None,
-    ) -> None:
-        return self.__original.__exit__(exc_type, exc_val, exc_tb)
+    ) -> bool | None:
+        # https://github.com/python-trio/trio-typing/pull/79
+        return self.__original.__exit__(  # type: ignore[func-returns-value]
+            exc_type, exc_val, exc_tb
+        )
 
     def cancel(self) -> None:
         self.__original.cancel()
@@ -1007,17 +1010,21 @@ async def getaddrinfo(
         type: int | SocketKind = 0,
         proto: int = 0,
         flags: int = 0,
-    ) -> GetAddrInfoReturnType:
-        # https://github.com/python-trio/trio-typing/pull/57
-        return await trio.socket.getaddrinfo(  # type: ignore[return-value]
-            host, port, family, type, proto, flags
-        )
+    ) -> list[
+        tuple[
+            AddressFamily,
+            SocketKind,
+            int,
+            str,
+            tuple[str, int] | tuple[str, int, int, int],
+        ]
+    ]:
+        return await trio.socket.getaddrinfo(host, port, family, type, proto, flags)
 
     @classmethod
     async def getnameinfo(
         cls, sockaddr: IPSockAddrType, flags: int = 0
     ) -> tuple[str, str]:
-        # https://github.com/python-trio/trio-typing/pull/56
         return await trio.socket.getnameinfo(sockaddr, flags)
 
     @classmethod

src/anyio/_core/_sockets.py

@@ -8,7 +8,7 @@
 from os import PathLike, chmod
 from pathlib import Path
 from socket import AddressFamily, SocketKind
-from typing import List, Tuple, cast, overload
+from typing import Tuple, cast, overload
 
 from .. import to_thread
 from ..abc import (
@@ -39,9 +39,6 @@
 
 IPPROTO_IPV6 = getattr(socket, "IPPROTO_IPV6", 41)  # https://bugs.python.org/issue29515
 
-GetAddrInfoReturnType = List[
-    Tuple[AddressFamily, SocketKind, int, str, Tuple[str, int]]
-]
 AnyIPAddressFamily = Literal[
     AddressFamily.AF_UNSPEC, AddressFamily.AF_INET, AddressFamily.AF_INET6
 ]
@@ -529,7 +526,7 @@ async def getaddrinfo(
     type: int | SocketKind = 0,
     proto: int = 0,
     flags: int = 0,
-) -> GetAddrInfoReturnType:
+) -> list[tuple[AddressFamily, SocketKind, int, str, tuple[str, int]]]:
     """
     Look up a numeric IP address given a host name.
 

src/anyio/abc/_eventloop.py

@@ -20,7 +20,6 @@
 if TYPE_CHECKING:
     from typing import Literal
 
-    from .._core._sockets import GetAddrInfoReturnType
     from .._core._synchronization import CapacityLimiter, Event
     from .._core._tasks import CancelScope
     from .._core._testing import TaskInfo
@@ -317,7 +316,15 @@ async def getaddrinfo(
         type: int | SocketKind = 0,
         proto: int = 0,
         flags: int = 0,
-    ) -> GetAddrInfoReturnType:
+    ) -> list[
+        tuple[
+            AddressFamily,
+            SocketKind,
+            int,
+            str,
+            tuple[str, int] | tuple[str, int, int, int],
+        ]
+    ]:
         pass
 
     @classmethod