Make wait() private

We don't really need to make it a public method, as one can just use
`await service` to await for it. It is still good to have it separate
as implementing `__await__` is easier based on another awaitable.

Signed-off-by: Leandro Lucarella <[email protected]>

Author: llucax

src/frequenz/core/asyncio.py

@@ -401,7 +401,7 @@ async def stop(self, msg: str | None = None) -> None:
             return
         self.cancel(msg)
         try:
-            await self.wait()
+            await self
         except BaseExceptionGroup as exc_group:
             # We want to ignore CancelledError here as we explicitly cancelled all the
             # tasks.
@@ -441,7 +441,7 @@ async def __aexit__(
         """
         await self.stop()
 
-    async def wait(self) -> None:
+    async def _wait(self) -> None:
         """Wait for this service to finish.
 
         Wait until all the service tasks are finished.
@@ -483,7 +483,7 @@ def __await__(self) -> collections.abc.Generator[None, None, None]:
         Returns:
             An implementation-specific generator for the awaitable.
         """
-        return self.wait().__await__()
+        return self._wait().__await__()
 
     def __del__(self) -> None:
         """Destroy this instance.

tests/test_asyncio.py

@@ -110,9 +110,9 @@ async def test_start_stop() -> None:
     assert fake_service.is_running is False
 
 
-@pytest.mark.parametrize("method", ["await", "wait", "stop"])
+@pytest.mark.parametrize("method", ["await", "stop"])
 async def test_start_and_crash(
-    method: Literal["await"] | Literal["wait"] | Literal["stop"],
+    method: Literal["await"] | Literal["stop"],
 ) -> None:
     """Test a service reports when crashing."""
     exc = RuntimeError("error")
@@ -125,8 +125,6 @@ async def test_start_and_crash(
         match method:
             case "await":
                 await fake_service
-            case "wait":
-                await fake_service.wait()
             case "stop":
                 # Give the service some time to run and crash, otherwise stop() will
                 # cancel it before it has a chance to crash