Fix: Transfer debt (#1615)

* fix: blocking transfer debt by epoch and redemptions.

* feat: make change_id deterministic

* fix: build

pallets/pool-system/src/impls.rs

@@ -401,12 +401,13 @@ impl<T: Config> ChangeGuard for Pallet<T> {
 	type PoolId = T::PoolId;
 
 	fn note(pool_id: Self::PoolId, change: Self::Change) -> Result<Self::ChangeId, DispatchError> {
+		// NOTE: Essentially, this key-generation allows to override previously
+		//       submitted changes, if they are identical.
+		let change_id: Self::ChangeId = T::Hashing::hash(&change.encode());
 		let noted_change = NotedPoolChange {
 			submitted_time: T::Time::now(),
 			change,
 		};
-
-		let change_id: Self::ChangeId = T::Hashing::hash(&noted_change.encode());
 		NotedChange::<T>::insert(pool_id, change_id, noted_change.clone());
 
 		Self::deposit_event(Event::ProposedChange {

pallets/pool-system/src/tests/mod.rs

@@ -2449,12 +2449,14 @@ mod changes {
 			let change = PoolChangeProposal::new([Requirement::DelayTime(2)]);
 			let change_id_3 = PoolSystem::note(DEFAULT_POOL_ID, change).unwrap();
 
-			// Same change but different moment;
+			// Same change but different moment so overwrites
 			util::advance_secs(1);
 			let change = PoolChangeProposal::new([Requirement::DelayTime(2)]);
 			let change_id_4 = PoolSystem::note(DEFAULT_POOL_ID, change).unwrap();
 
-			let ids = [change_id_1, change_id_2, change_id_3, change_id_4];
+			assert_eq!(change_id_4, change_id_3);
+
+			let ids = [change_id_1, change_id_2, change_id_3];
 			assert_eq!(BTreeSet::from(ids.clone()).len(), ids.len());
 		});
 	}

runtime/common/src/lib.rs

@@ -293,7 +293,7 @@ pub mod changes {
 					},
 				},
 				LoansChange::<T>::Policy(_) => vec![week, blocked],
-				LoansChange::<T>::TransferDebt(_, _, _, _) => vec![epoch, blocked],
+				LoansChange::<T>::TransferDebt(_, _, _, _) => vec![],
 			};
 
 			PoolChangeProposal::new(requirements)