run pyupgrade --py38-plus

trio/_channel.py

@@ -99,7 +99,7 @@ def _open_memory_channel(
 if TYPE_CHECKING:
     # written as a class so you can say open_memory_channel[int](5)
     # Need to use Tuple instead of tuple due to CI check running on 3.8
-    class open_memory_channel(Tuple[MemorySendChannel[T], MemoryReceiveChannel[T]]):
+    class open_memory_channel(tuple[MemorySendChannel[T], MemoryReceiveChannel[T]]):
         def __new__(  # type: ignore[misc]  # "must return a subtype"
             cls, max_buffer_size: int
         ) -> tuple[MemorySendChannel[T], MemoryReceiveChannel[T]]:
@@ -218,7 +218,7 @@ def abort_fn(_: RaiseCancelT) -> Abort:
 
     # Return type must be stringified or use a TypeVar
     @enable_ki_protection
-    def clone(self) -> "MemorySendChannel[SendType]":
+    def clone(self) -> MemorySendChannel[SendType]:
         """Clone this send channel object.
 
         This returns a new `MemorySendChannel` object, which acts as a
@@ -361,7 +361,7 @@ def abort_fn(_: RaiseCancelT) -> Abort:
         return await trio.lowlevel.wait_task_rescheduled(abort_fn)  # type: ignore[no-any-return]
 
     @enable_ki_protection
-    def clone(self) -> "MemoryReceiveChannel[ReceiveType]":
+    def clone(self) -> MemoryReceiveChannel[ReceiveType]:
         """Clone this receive channel object.
 
         This returns a new `MemoryReceiveChannel` object, which acts as a

trio/_core/_run.py

@@ -46,7 +46,7 @@
 
 if TYPE_CHECKING:
     # An unfortunate name collision here with trio._util.Final
-    from typing_extensions import Final as FinalT
+    from typing import Final as FinalT
 
 DEADLINE_HEAP_MIN_PRUNE_THRESHOLD: FinalT = 1000
 
@@ -1312,7 +1312,7 @@ def raise_cancel():
 
 
 class RunContext(threading.local):
-    runner: "Runner"
+    runner: Runner
     task: Task
 
 

trio/_tests/test_exports.py

@@ -263,7 +263,7 @@ def no_hidden(symbols):
             cache_json = json.loads(cache_file.read())
 
         # skip a bunch of file-system activity (probably can un-memoize?)
-        @functools.lru_cache()
+        @functools.lru_cache
         def lookup_symbol(symbol):
             topname, *modname, name = symbol.split(".")
             version = next(cache.glob("3.*/"))

trio/_unix_pipes.py

@@ -10,7 +10,7 @@
 import trio
 
 if TYPE_CHECKING:
-    from typing_extensions import Final as FinalType
+    from typing import Final as FinalType
 
 if os.name != "posix":
     # We raise an error here rather than gating the import in lowlevel.py