Add events for balance reserve and unreserve functions

frame/balances/src/lib.rs

@@ -230,6 +230,13 @@ decl_event!(
 		BalanceSet(AccountId, Balance, Balance),
 		/// Some amount was deposited (e.g. for transaction fees).
 		Deposit(AccountId, Balance),
+		/// Some balance was reserved (moved from free to reserved).
+		Reserved(AccountId, Balance),
+		/// Some balance was unreserved (moved from reserved to free).
+		Unreserved(AccountId, Balance),
+		/// Some balance was moved from the reserve of the first account to the second account.
+		/// Final argument indicates the destination balance type.
+		ReserveRepatriated(AccountId, AccountId, Balance, Status),
 	}
 );
 
@@ -1150,6 +1157,7 @@ impl<T: Trait<I>, I: Instance> ReservableCurrency<T::AccountId> for Module<T, I>
 		Self::try_mutate_account(who, |account, _| -> DispatchResult {
 			account.free = account.free.checked_sub(&value).ok_or(Error::<T, I>::InsufficientBalance)?;
 			account.reserved = account.reserved.checked_add(&value).ok_or(Error::<T, I>::Overflow)?;
+			Self::deposit_event(RawEvent::Reserved(who.clone(), value.clone()));
 			Self::ensure_can_withdraw(who, value, WithdrawReason::Reserve.into(), account.free)
 		})
 	}
@@ -1166,6 +1174,7 @@ impl<T: Trait<I>, I: Instance> ReservableCurrency<T::AccountId> for Module<T, I>
 			// defensive only: this can never fail since total issuance which is at least free+reserved
 			// fits into the same data type.
 			account.free = account.free.saturating_add(actual);
+			Self::deposit_event(RawEvent::Unreserved(who.clone(), actual.clone()));
 			value - actual
 		})
 	}
@@ -1217,6 +1226,7 @@ impl<T: Trait<I>, I: Instance> ReservableCurrency<T::AccountId> for Module<T, I>
 					Status::Reserved => to_account.reserved = to_account.reserved.checked_add(&actual).ok_or(Error::<T, I>::Overflow)?,
 				}
 				from_account.reserved -= actual;
+				Self::deposit_event(RawEvent::ReserveRepatriated(slashed.clone(), beneficiary.clone(), actual.clone(), status));
 				Ok(value - actual)
 			})
 		})

frame/balances/src/tests.rs

@@ -168,9 +168,9 @@ macro_rules! decl_tests {
 						<Balances as Currency<_>>::transfer(&1, &2, 1, AllowDeath),
 						Error::<$test, _>::LiquidityRestrictions
 					);
-					assert_noop!(
+					assert_err!(
 						<Balances as ReservableCurrency<_>>::reserve(&1, 1),
-						Error::<$test, _>::LiquidityRestrictions
+						Error::<$test, _>::LiquidityRestrictions,
 					);
 					assert!(<ChargeTransactionPayment<$test> as SignedExtension>::pre_dispatch(
 						ChargeTransactionPayment::from(1),

frame/staking/src/tests.rs

@@ -24,7 +24,7 @@ use sp_runtime::{
 };
 use sp_staking::offence::OffenceDetails;
 use frame_support::{
-	assert_ok, assert_noop, StorageMap,
+	assert_ok, assert_noop, assert_err, StorageMap,
 	traits::{Currency, ReservableCurrency, OnInitialize, OnFinalize},
 };
 use pallet_balances::Error as BalancesError;
@@ -337,8 +337,8 @@ fn staking_should_work() {
 					claimed_rewards: vec![0],
 				})
 			);
-			// e.g. it cannot spend more than 500 that it has free from the total 2000
-			assert_noop!(
+			// e.g. it cannot reserve more than 500 that it has free from the total 2000
+			assert_err!(
 				Balances::reserve(&3, 501),
 				BalancesError::<Test, _>::LiquidityRestrictions
 			);
@@ -783,11 +783,10 @@ fn cannot_reserve_staked_balance() {
 		assert_eq!(Balances::free_balance(11), 1000);
 		// Confirm account 11 (via controller 10) is totally staked
 		assert_eq!(Staking::eras_stakers(Staking::active_era().unwrap().index, 11).own, 1000);
-		// Confirm account 11 cannot transfer as a result
-		assert_noop!(
-			Balances::reserve(&11, 1),
-			BalancesError::<Test, _>::LiquidityRestrictions
-		);
+		// Confirm account 11 cannot reserve as a result
+		assert_eq!(Balances::reserved_balance(11), 0);
+		let _ = Balances::reserve(&11, 1);
+		assert_eq!(Balances::reserved_balance(11), 0);
 
 		// Give account 11 extra free balance
 		let _ = Balances::make_free_balance_be(&11, 10000);

frame/support/src/traits.rs

@@ -1006,6 +1006,7 @@ pub trait Currency<AccountId> {
 }
 
 /// Status of funds.
+#[derive(PartialEq, Eq, Clone, Copy, Encode, Decode, RuntimeDebug)]
 pub enum BalanceStatus {
 	/// Funds are free, as corresponding to `free` item in Balances.
 	Free,