Changed vested_transfer extrinsic behavior. (#857)

* Changed `vested_transfer` extrinsic behavior.
Fixed self-vesting case (`from` == `to`) when it was possible to self-freeze funds above the current account balance.

* added test for self-vesting case

vesting/src/lib.rs

@@ -264,6 +264,14 @@ pub mod module {
 		) -> DispatchResult {
 			let from = T::VestedTransferOrigin::ensure_origin(origin)?;
 			let to = T::Lookup::lookup(dest)?;
+
+			if to == from {
+				ensure!(
+					T::Currency::free_balance(&from) >= schedule.total_amount().ok_or(ArithmeticError::Overflow)?,
+					Error::<T>::InsufficientBalanceToLock,
+				);
+			}
+
 			Self::do_vested_transfer(&from, &to, schedule.clone())?;
 
 			Self::deposit_event(Event::VestingScheduleAdded {

vesting/src/mock.rs

@@ -116,6 +116,9 @@ pub const ALICE: AccountId = 1;
 pub const BOB: AccountId = 2;
 pub const CHARLIE: AccountId = 3;
 
+pub const ALICE_BALANCE: u64 = 100;
+pub const CHARLIE_BALANCE: u64 = 50;
+
 #[derive(Default)]
 pub struct ExtBuilder;
 
@@ -126,7 +129,7 @@ impl ExtBuilder {
 			.unwrap();
 
 		pallet_balances::GenesisConfig::<Runtime> {
-			balances: vec![(ALICE, 100), (CHARLIE, 50)],
+			balances: vec![(ALICE, ALICE_BALANCE), (CHARLIE, CHARLIE_BALANCE)],
 		}
 		.assimilate_storage(&mut t)
 		.unwrap();

vesting/src/tests.rs

@@ -87,6 +87,45 @@ fn vested_transfer_works() {
 	});
 }
 
+#[test]
+fn self_vesting() {
+	ExtBuilder::build().execute_with(|| {
+		System::set_block_number(1);
+
+		let schedule = VestingSchedule {
+			start: 0u64,
+			period: 10u64,
+			period_count: 1u32,
+			per_period: ALICE_BALANCE,
+		};
+
+		let bad_schedule = VestingSchedule {
+			start: 0u64,
+			period: 10u64,
+			period_count: 1u32,
+			per_period: 10 * ALICE_BALANCE,
+		};
+
+		assert_noop!(
+			Vesting::vested_transfer(RuntimeOrigin::signed(ALICE), ALICE, bad_schedule),
+			crate::Error::<Runtime>::InsufficientBalanceToLock
+		);
+
+		assert_ok!(Vesting::vested_transfer(
+			RuntimeOrigin::signed(ALICE),
+			ALICE,
+			schedule.clone()
+		));
+
+		assert_eq!(Vesting::vesting_schedules(&ALICE), vec![schedule.clone()]);
+		System::assert_last_event(RuntimeEvent::Vesting(crate::Event::VestingScheduleAdded {
+			from: ALICE,
+			to: ALICE,
+			vesting_schedule: schedule,
+		}));
+	});
+}
+
 #[test]
 fn add_new_vesting_schedule_merges_with_current_locked_balance_and_until() {
 	ExtBuilder::build().execute_with(|| {