approval-distribution: Fix handling of conclude

After
moonbeam-foundation@53373a9,
approval-distribution did not terminate anymore if Conclude signal was
received.

This should have been caught by the subsystem tests, but it
wasn't because the subsystem is also exiting on error when the channels
are dropped so the test overseer was dropped which made the susbystem
exit and masked the problem.

This pr fixes both the test and the subsystem.

Signed-off-by: Alexandru Gheorghe <alexandru.gheorghe@parity.io>

polkadot/node/network/approval-distribution/src/lib.rs

@@ -2508,14 +2508,18 @@ impl ApprovalDistribution {
 					};
 
 
-					self.handle_from_orchestra(message, &mut approval_voting_sender, &mut network_sender, state, rng).await;
+					if self.handle_from_orchestra(message, &mut approval_voting_sender, &mut network_sender, state, rng).await {
+						return;
+					}
 
 				},
 			}
 		}
 	}
 
 	/// Handles a from orchestra message received by approval distribution subystem.
+	///
+	/// Returns `true` if the subsystem should be stopped.
 	pub async fn handle_from_orchestra<
 		N: overseer::SubsystemSender<NetworkBridgeTxMessage>,
 		A: overseer::SubsystemSender<ApprovalVotingMessage>,
@@ -2526,7 +2530,7 @@ impl ApprovalDistribution {
 		network_sender: &mut N,
 		state: &mut State,
 		rng: &mut (impl CryptoRng + Rng),
-	) {
+	) -> bool {
 		match message {
 			FromOrchestra::Communication { msg } =>
 				Self::handle_incoming(
@@ -2555,8 +2559,9 @@ impl ApprovalDistribution {
 				gum::trace!(target: LOG_TARGET, number = %number, "finalized signal");
 				state.handle_block_finalized(network_sender, &self.metrics, number).await;
 			},
-			FromOrchestra::Signal(OverseerSignal::Conclude) => return,
+			FromOrchestra::Signal(OverseerSignal::Conclude) => return true,
 		}
+		false
 	}
 
 	async fn handle_incoming<

polkadot/node/network/approval-distribution/src/tests.rs

@@ -59,9 +59,13 @@ fn test_harness<T: Future<Output = VirtualOverseer>>(
 	let subsystem = ApprovalDistribution::new(Default::default());
 	{
 		let mut rng = rand_chacha::ChaCha12Rng::seed_from_u64(12345);
-
-		let subsystem =
-			subsystem.run_inner(context, &mut state, REPUTATION_CHANGE_TEST_INTERVAL, &mut rng);
+		let (tx, rx) = oneshot::channel();
+		let subsystem = async {
+			subsystem
+				.run_inner(context, &mut state, REPUTATION_CHANGE_TEST_INTERVAL, &mut rng)
+				.await;
+			tx.send(()).expect("Fail to notify subystem is done");
+		};
 
 		let test_fut = test_fn(virtual_overseer);
 
@@ -76,6 +80,8 @@ fn test_harness<T: Future<Output = VirtualOverseer>>(
 					.timeout(TIMEOUT)
 					.await
 					.expect("Conclude send timeout");
+				let _ =
+					rx.timeout(Duration::from_secs(2)).await.expect("Subsystem did not conclude");
 			},
 			subsystem,
 		));