Fixes TotalValueLocked out of sync in nomination pools (#3052)

The `TotalLockedValue` storage value in nomination pools pallet may get out of sync if the staking pallet does implicit withdrawal of unlocking chunks belonging to a bonded pool stash. This fix is based on a new method in the `OnStakingUpdate` traits, `on_withdraw`, which allows the nomination pools pallet to adjust the `TotalLockedValue` every time there is an implicit or explicit withdrawal from a bonded pool's stash. This PR also adds a migration that checks and updates the on-chain TVL if it got out of sync due to the bug this PR fixes. **Changes to `trait OnStakingUpdate`** In order for staking to notify the nomination pools pallet that chunks where withdrew, we add a new method, `on_withdraw` to the `OnStakingUpdate` trait. The nomination pools pallet filters the withdraws that are related to bonded pool accounts and updates the `TotalValueLocked` accordingly. **Others** - Adds try-state checks to the EPM/staking e2e tests - Adds tests for auto withdrawing in the context of nomination pools **To-do** - [x] check if we need a migration to fix the current `TotalValueLocked` (run try-runtime) - [x] migrations to fix the current on-chain TVL value ✅ **Kusama**: ``` TotalValueLocked: 99.4559 kKSM TotalValueLocked (calculated) 99.4559 kKSM ``` ⚠️ **Westend**: ``` TotalValueLocked: 18.4060 kWND TotalValueLocked (calculated) 18.4050 kWND ``` **Polkadot**: TVL not released yet. Closes https://github.com/paritytech/polkadot-sdk/issues/3055 --------- Co-authored-by: command-bot <> Co-authored-by: Ross Bulat <ross@parity.io> Co-authored-by: Dónal Murray <donal.murray@parity.io>
2026-06-12 10:01:17 +00:00 · 2024-02-08 19:03:22 +01:00
parent c36c51cac3
commit aac07af03c
12 changed files with 383 additions and 74 deletions
@@ -53,9 +53,9 @@ fn log_current_time() {

 #[test]
 fn block_progression_works() {
-	let (mut ext, pool_state, _) = ExtBuilder::default().build_offchainify();
+	let (ext, pool_state, _) = ExtBuilder::default().build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		assert_eq!(active_era(), 0);
 		assert_eq!(Session::current_index(), 0);
 		assert!(ElectionProviderMultiPhase::current_phase().is_off());
@@ -70,9 +70,9 @@ fn block_progression_works() {
 		assert!(ElectionProviderMultiPhase::current_phase().is_signed());
 	});

-	let (mut ext, pool_state, _) = ExtBuilder::default().build_offchainify();
+	let (ext, pool_state, _) = ExtBuilder::default().build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		assert_eq!(active_era(), 0);
 		assert_eq!(Session::current_index(), 0);
 		assert!(ElectionProviderMultiPhase::current_phase().is_off());
@@ -93,12 +93,12 @@ fn offchainify_works() {

 	let staking_builder = StakingExtBuilder::default();
 	let epm_builder = EpmExtBuilder::default();
-	let (mut ext, pool_state, _) = ExtBuilder::default()
+	let (ext, pool_state, _) = ExtBuilder::default()
 		.epm(epm_builder)
 		.staking(staking_builder)
 		.build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		// test ocw progression and solution queue if submission when unsigned phase submission is
 		// not delayed.
 		for _ in 0..100 {
@@ -142,9 +142,9 @@ fn offchainify_works() {
 /// restarts. Note that in this test case, the emergency throttling is disabled.
 fn enters_emergency_phase_after_forcing_before_elect() {
 	let epm_builder = EpmExtBuilder::default().disable_emergency_throttling();
-	let (mut ext, pool_state, _) = ExtBuilder::default().epm(epm_builder).build_offchainify();
+	let (ext, pool_state, _) = ExtBuilder::default().epm(epm_builder).build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		log!(
 			trace,
 			"current validators (staking): {:?}",
@@ -213,12 +213,12 @@ fn continous_slashes_below_offending_threshold() {
 	let staking_builder = StakingExtBuilder::default().validator_count(10);
 	let epm_builder = EpmExtBuilder::default().disable_emergency_throttling();

-	let (mut ext, pool_state, _) = ExtBuilder::default()
+	let (ext, pool_state, _) = ExtBuilder::default()
 		.epm(epm_builder)
 		.staking(staking_builder)
 		.build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		assert_eq!(Session::validators().len(), 10);
 		let mut active_validator_set = Session::validators();

@@ -271,12 +271,12 @@ fn set_validation_intention_after_chilled() {
 	use frame_election_provider_support::SortedListProvider;
 	use pallet_staking::{Event, Forcing, Nominators};

-	let (mut ext, pool_state, _) = ExtBuilder::default()
+	let (ext, pool_state, _) = ExtBuilder::default()
 		.epm(EpmExtBuilder::default())
 		.staking(StakingExtBuilder::default())
 		.build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		assert_eq!(active_era(), 0);
 		// validator is part of the validator set.
 		assert!(Session::validators().contains(&41));
@@ -334,10 +334,10 @@ fn set_validation_intention_after_chilled() {
 fn ledger_consistency_active_balance_below_ed() {
 	use pallet_staking::{Error, Event};

-	let (mut ext, pool_state, _) =
+	let (ext, pool_state, _) =
 		ExtBuilder::default().staking(StakingExtBuilder::default()).build_offchainify();

-	ext.execute_with(|| {
+	execute_with(ext, || {
 		assert_eq!(Staking::ledger(11.into()).unwrap().active, 1000);

 		// unbonding total of active stake fails because the active ledger balance would fall
@@ -387,3 +387,141 @@ fn ledger_consistency_active_balance_below_ed() {
 		assert!(Staking::ledger(11.into()).is_err());
 	});
 }
+
+#[test]
+/// Automatic withdrawal of unlocking funds in staking propagates to the nomination pools and its
+/// state correctly.
+///
+/// The staking pallet may withdraw unlocking funds from a pool's bonded account without a pool
+/// member or operator calling explicitly `Call::withdraw*`. This test verifies that the member's
+/// are eventually paid and the `TotalValueLocked` is kept in sync in those cases.
+fn automatic_unbonding_pools() {
+	use pallet_nomination_pools::TotalValueLocked;
+
+	// closure to fetch the staking unlocking chunks of an account.
+	let unlocking_chunks_of = |account: AccountId| -> usize {
+		Staking::ledger(sp_staking::StakingAccount::Controller(account))
+			.unwrap()
+			.unlocking
+			.len()
+	};
+
+	let (ext, pool_state, _) = ExtBuilder::default()
+		.pools(PoolsExtBuilder::default().max_unbonding(1))
+		.staking(StakingExtBuilder::default().max_unlocking(1).bonding_duration(2))
+		.build_offchainify();
+
+	execute_with(ext, || {
+		assert_eq!(<Runtime as pallet_staking::Config>::MaxUnlockingChunks::get(), 1);
+		assert_eq!(<Runtime as pallet_staking::Config>::BondingDuration::get(), 2);
+		assert_eq!(<Runtime as pallet_nomination_pools::Config>::MaxUnbonding::get(), 1);
+
+		// init state of pool members.
+		let init_free_balance_2 = Balances::free_balance(2);
+		let init_free_balance_3 = Balances::free_balance(3);
+
+		let pool_bonded_account = Pools::create_bonded_account(1);
+
+		// creates a pool with 5 bonded, owned by 1.
+		assert_ok!(Pools::create(RuntimeOrigin::signed(1), 5, 1, 1, 1));
+		assert_eq!(locked_amount_for(pool_bonded_account), 5);
+
+		let init_tvl = TotalValueLocked::<Runtime>::get();
+
+		// 2 joins the pool.
+		assert_ok!(Pools::join(RuntimeOrigin::signed(2), 10, 1));
+		assert_eq!(locked_amount_for(pool_bonded_account), 15);
+
+		// 3 joins the pool.
+		assert_ok!(Pools::join(RuntimeOrigin::signed(3), 10, 1));
+		assert_eq!(locked_amount_for(pool_bonded_account), 25);
+
+		assert_eq!(TotalValueLocked::<Runtime>::get(), 25);
+
+		// currently unlocking 0 chunks in the bonded pools ledger.
+		assert_eq!(unlocking_chunks_of(pool_bonded_account), 0);
+
+		// unbond 2 from pool.
+		assert_ok!(Pools::unbond(RuntimeOrigin::signed(2), 2, 10));
+
+		// amount is still locked in the pool, needs to wait for unbonding period.
+		assert_eq!(locked_amount_for(pool_bonded_account), 25);
+
+		// max chunks in the ledger are now filled up (`MaxUnlockingChunks == 1`).
+		assert_eq!(unlocking_chunks_of(pool_bonded_account), 1);
+
+		// tries to unbond 3 from pool. it will fail since there are no unlocking chunks left
+		// available and the current in the queue haven't been there for more than bonding
+		// duration.
+		assert_err!(
+			Pools::unbond(RuntimeOrigin::signed(3), 3, 10),
+			pallet_staking::Error::<Runtime>::NoMoreChunks
+		);
+
+		assert_eq!(current_era(), 0);
+
+		// progress over bonding duration.
+		for _ in 0..=<Runtime as pallet_staking::Config>::BondingDuration::get() {
+			start_next_active_era(pool_state.clone()).unwrap();
+		}
+		assert_eq!(current_era(), 3);
+		System::reset_events();
+
+		let locked_before_withdraw_pool = locked_amount_for(pool_bonded_account);
+		assert_eq!(Balances::free_balance(pool_bonded_account), 26);
+
+		// now unbonding 3 will work, although the pool's ledger still has the unlocking chunks
+		// filled up.
+		assert_ok!(Pools::unbond(RuntimeOrigin::signed(3), 3, 10));
+		assert_eq!(unlocking_chunks_of(pool_bonded_account), 1);
+
+		assert_eq!(
+			staking_events(),
+			[
+				// auto-withdraw happened as expected to release 2's unbonding funds, but the funds
+				// were not transfered to 2 and stay in the pool's tranferrable balance instead.
+				pallet_staking::Event::Withdrawn { stash: 7939698191839293293, amount: 10 },
+				pallet_staking::Event::Unbonded { stash: 7939698191839293293, amount: 10 }
+			]
+		);
+
+		// balance of the pool remains the same, it hasn't withdraw explicitly from the pool yet.
+		assert_eq!(Balances::free_balance(pool_bonded_account), 26);
+		// but the locked amount in the pool's account decreases due to the auto-withdraw:
+		assert_eq!(locked_before_withdraw_pool - 10, locked_amount_for(pool_bonded_account));
+
+		// TVL correctly updated.
+		assert_eq!(TotalValueLocked::<Runtime>::get(), 25 - 10);
+
+		// however, note that the withdrawing from the pool still works for 2, the funds are taken
+		// from the pool's free balance.
+		assert_eq!(Balances::free_balance(pool_bonded_account), 26);
+		assert_ok!(Pools::withdraw_unbonded(RuntimeOrigin::signed(2), 2, 10));
+		assert_eq!(Balances::free_balance(pool_bonded_account), 16);
+
+		assert_eq!(Balances::free_balance(2), 20);
+		assert_eq!(TotalValueLocked::<Runtime>::get(), 15);
+
+		// 3 cannot withdraw yet.
+		assert_err!(
+			Pools::withdraw_unbonded(RuntimeOrigin::signed(3), 3, 10),
+			pallet_nomination_pools::Error::<Runtime>::CannotWithdrawAny
+		);
+
+		// progress over bonding duration.
+		for _ in 0..=<Runtime as pallet_staking::Config>::BondingDuration::get() {
+			start_next_active_era(pool_state.clone()).unwrap();
+		}
+		assert_eq!(current_era(), 6);
+		System::reset_events();
+
+		assert_ok!(Pools::withdraw_unbonded(RuntimeOrigin::signed(3), 3, 10));
+
+		// final conditions are the expected.
+		assert_eq!(Balances::free_balance(pool_bonded_account), 6); // 5 init bonded + ED
+		assert_eq!(Balances::free_balance(2), init_free_balance_2);
+		assert_eq!(Balances::free_balance(3), init_free_balance_3);
+
+		assert_eq!(TotalValueLocked::<Runtime>::get(), init_tvl);
+	});
+}
@@ -69,6 +69,7 @@ frame_support::construct_runtime!(
 		System: frame_system,
 		ElectionProviderMultiPhase: pallet_election_provider_multi_phase,
 		Staking: pallet_staking,
+		Pools: pallet_nomination_pools,
 		Balances: pallet_balances,
 		BagsList: pallet_bags_list,
 		Session: pallet_session,
@@ -114,7 +115,7 @@ impl pallet_balances::Config for Runtime {
 	type MaxFreezes = traits::ConstU32<1>;
 	type RuntimeHoldReason = RuntimeHoldReason;
 	type RuntimeFreezeReason = RuntimeFreezeReason;
-	type FreezeIdentifier = ();
+	type FreezeIdentifier = RuntimeFreezeReason;
 	type WeightInfo = ();
 }

@@ -233,7 +234,7 @@ const THRESHOLDS: [VoteWeight; 9] = [10, 20, 30, 40, 50, 60, 1_000, 2_000, 10_00
 parameter_types! {
 	pub static BagThresholds: &'static [sp_npos_elections::VoteWeight] = &THRESHOLDS;
 	pub const SessionsPerEra: sp_staking::SessionIndex = 2;
-	pub const BondingDuration: sp_staking::EraIndex = 28;
+	pub static BondingDuration: sp_staking::EraIndex = 28;
 	pub const SlashDeferDuration: sp_staking::EraIndex = 7; // 1/4 the bonding duration.
 	pub const OffendingValidatorsThreshold: Perbill = Perbill::from_percent(40);
 	pub HistoryDepth: u32 = 84;
@@ -247,6 +248,45 @@ impl pallet_bags_list::Config for Runtime {
 	type Score = VoteWeight;
 }

+pub struct BalanceToU256;
+impl sp_runtime::traits::Convert<Balance, sp_core::U256> for BalanceToU256 {
+	fn convert(n: Balance) -> sp_core::U256 {
+		n.into()
+	}
+}
+
+pub struct U256ToBalance;
+impl sp_runtime::traits::Convert<sp_core::U256, Balance> for U256ToBalance {
+	fn convert(n: sp_core::U256) -> Balance {
+		n.try_into().unwrap()
+	}
+}
+
+parameter_types! {
+	pub const PoolsPalletId: frame_support::PalletId = frame_support::PalletId(*b"py/nopls");
+	pub static MaxUnbonding: u32 = 8;
+}
+
+impl pallet_nomination_pools::Config for Runtime {
+	type RuntimeEvent = RuntimeEvent;
+	type WeightInfo = ();
+	type Currency = Balances;
+	type RuntimeFreezeReason = RuntimeFreezeReason;
+	type RewardCounter = sp_runtime::FixedU128;
+	type BalanceToU256 = BalanceToU256;
+	type U256ToBalance = U256ToBalance;
+	type Staking = Staking;
+	type PostUnbondingPoolsWindow = ConstU32<2>;
+	type PalletId = PoolsPalletId;
+	type MaxMetadataLen = ConstU32<256>;
+	type MaxUnbonding = MaxUnbonding;
+	type MaxPointsToBalance = frame_support::traits::ConstU8<10>;
+}
+
+parameter_types! {
+	pub static MaxUnlockingChunks: u32 = 32;
+}
+
 /// Upper limit on the number of NPOS nominations.
 const MAX_QUOTA_NOMINATIONS: u32 = 16;

@@ -273,10 +313,10 @@ impl pallet_staking::Config for Runtime {
 	type VoterList = BagsList;
 	type NominationsQuota = pallet_staking::FixedNominationsQuota<MAX_QUOTA_NOMINATIONS>;
 	type TargetList = pallet_staking::UseValidatorsMap<Self>;
-	type MaxUnlockingChunks = ConstU32<32>;
+	type MaxUnlockingChunks = MaxUnlockingChunks;
 	type MaxControllersInDeprecationBatch = ConstU32<100>;
 	type HistoryDepth = HistoryDepth;
-	type EventListeners = ();
+	type EventListeners = Pools;
 	type WeightInfo = pallet_staking::weights::SubstrateWeight<Runtime>;
 	type BenchmarkingConfig = pallet_staking::TestBenchmarkingConfig;
 }
@@ -394,6 +434,14 @@ impl StakingExtBuilder {
 		self.validator_count = n;
 		self
 	}
+	pub fn max_unlocking(self, max: u32) -> Self {
+		<MaxUnlockingChunks>::set(max);
+		self
+	}
+	pub fn bonding_duration(self, eras: EraIndex) -> Self {
+		<BondingDuration>::set(eras);
+		self
+	}
 }

 pub struct EpmExtBuilder {}
@@ -417,6 +465,21 @@ impl EpmExtBuilder {
 	}
 }

+pub struct PoolsExtBuilder {}
+
+impl Default for PoolsExtBuilder {
+	fn default() -> Self {
+		PoolsExtBuilder {}
+	}
+}
+
+impl PoolsExtBuilder {
+	pub fn max_unbonding(self, max: u32) -> Self {
+		<MaxUnbonding>::set(max);
+		self
+	}
+}
+
 pub struct BalancesExtBuilder {
 	balances: Vec<(AccountId, Balance)>,
 }
@@ -464,6 +527,7 @@ pub struct ExtBuilder {
 	staking_builder: StakingExtBuilder,
 	epm_builder: EpmExtBuilder,
 	balances_builder: BalancesExtBuilder,
+	pools_builder: PoolsExtBuilder,
 }

 impl Default for ExtBuilder {
@@ -472,6 +536,7 @@ impl Default for ExtBuilder {
 			staking_builder: StakingExtBuilder::default(),
 			epm_builder: EpmExtBuilder::default(),
 			balances_builder: BalancesExtBuilder::default(),
+			pools_builder: PoolsExtBuilder::default(),
 		}
 	}
 }
@@ -548,6 +613,11 @@ impl ExtBuilder {
 		self
 	}

+	pub fn pools(mut self, builder: PoolsExtBuilder) -> Self {
+		self.pools_builder = builder;
+		self
+	}
+
 	pub fn balances(mut self, builder: BalancesExtBuilder) -> Self {
 		self.balances_builder = builder;
 		self
@@ -567,20 +637,20 @@ impl ExtBuilder {

 		(ext, pool_state, offchain_state)
 	}
+}

-	pub fn build_and_execute(self, test: impl FnOnce() -> ()) {
-		let mut ext = self.build();
-		ext.execute_with(test);
+pub(crate) fn execute_with(mut ext: sp_io::TestExternalities, test: impl FnOnce() -> ()) {
+	ext.execute_with(test);

-		#[cfg(feature = "try-runtime")]
-		ext.execute_with(|| {
-			let bn = System::block_number();
+	#[cfg(feature = "try-runtime")]
+	ext.execute_with(|| {
+		let bn = System::block_number();

-			assert_ok!(<MultiPhase as Hooks<u64>>::try_state(bn));
-			assert_ok!(<Staking as Hooks<u64>>::try_state(bn));
-			assert_ok!(<Session as Hooks<u64>>::try_state(bn));
-		});
-	}
+		assert_ok!(<ElectionProviderMultiPhase as Hooks<BlockNumber>>::try_state(bn));
+		assert_ok!(<Staking as Hooks<BlockNumber>>::try_state(bn));
+		assert_ok!(<Pools as Hooks<BlockNumber>>::try_state(bn));
+		assert_ok!(<Session as Hooks<BlockNumber>>::try_state(bn));
+	});
 }

 // Progress to given block, triggering session and era changes as we progress and ensuring that
@@ -606,6 +676,7 @@ pub fn roll_to(n: BlockNumber, delay_solution: bool) {
 		if b != n {
 			Staking::on_finalize(System::block_number());
 		}
+		Pools::on_initialize(b);

 		log_current_time();
 	}
@@ -860,6 +931,11 @@ pub(crate) fn set_minimum_election_score(
 	.map_err(|_| ())
 }

+pub(crate) fn locked_amount_for(account_id: AccountId) -> Balance {
+	let lock = pallet_balances::Locks::<Runtime>::get(account_id);
+	lock[0].amount
+}
+
 pub(crate) fn staking_events() -> Vec<pallet_staking::Event<Runtime>> {
 	System::events()
 		.into_iter()