Don't use trio's deprecated warning, add test, add newsfragment

Author: CoolCat467

newsfragments/3322.deprecated.txt

@@ -0,0 +1 @@
+Implement `trio.Event.__bool__` and have it raise a `DeprecationWarning` and tell users to use `trio.Event.is_set` instead. Would be caught earlier with `mypy --enable-error-code=truthy-bool`, this is for users who don't use mypy.

src/trio/_sync.py

@@ -16,7 +16,7 @@
     enable_ki_protection,
     remove_parking_lot_breaker,
 )
-from ._depreciate import warn_deprecated
+from ._deprecate import warn_deprecated
 from ._util import final
 
 if TYPE_CHECKING:
@@ -120,7 +120,6 @@ def __bool__(self) -> True:
             "0.30.1",
             issue=3238,
             instead=self.is_set,
-            use_triodeprecationwarning=True,
         )
         return True
 

src/trio/_tests/test_sync.py

@@ -23,6 +23,12 @@ async def test_Event() -> None:
     assert not e.is_set()
     assert e.statistics().tasks_waiting == 0
 
+    with pytest.warns(
+        DeprecationWarning,
+        match=r"trio\.Event\.__bool__ is deprecated since Trio 0\.30\.1; use trio\.Event\.is_set instead \(https://github.com/python-trio/trio/issues/3238\)",
+    ):
+        e.__bool__()
+
     e.set()
     assert e.is_set()
     with assert_checkpoints():