HoldReason: Improve usage (#13869)

* HoldReason: Improve usage

`HoldReason` was switched recently to use the `composite_enum` attribute that will merge the enums
from all pallets in the runtime to `RuntimeHoldReason`. `pallet-nis` was still requiring that the
variant was passed as constant to call `hold`. The proper implementation is to use the `HoldReason`
from inside the pallet directly when calling `hold`. This is done by adding a `RuntimeHoldReason` as
type to the `Config` trait and requiring that `Currency` is using the same reason. Besides that the
pr changes the name `HoldIdentifier` in `pallet_balances::Config` to `RuntimeHoldReason`.

* Update frame/nis/src/lib.rs

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Review comment

* Fixes

---------

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/bin/node-template/runtime/src/lib.rs

@@ -245,7 +245,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = pallet_balances::weights::SubstrateWeight<Runtime>;
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/bin/node/runtime/src/lib.rs

@@ -59,7 +59,6 @@ use pallet_nis::WithMaximumOf;
 use pallet_session::historical as pallet_session_historical;
 pub use pallet_transaction_payment::{CurrencyAdapter, Multiplier, TargetedFeeAdjustment};
 use pallet_transaction_payment::{FeeDetails, RuntimeDispatchInfo};
-use scale_info::TypeInfo;
 use sp_api::impl_runtime_apis;
 use sp_authority_discovery::AuthorityId as AuthorityDiscoveryId;
 use sp_consensus_grandpa::AuthorityId as GrandpaId;
@@ -439,17 +438,6 @@ parameter_types! {
 	pub const MaxReserves: u32 = 50;
 }
 
-/// A reason for placing a hold on funds.
-#[derive(
-	Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, Debug, TypeInfo,
-)]
-pub enum HoldReason {
-	/// The NIS Pallet has reserved it for a non-fungible receipt.
-	Nis,
-	/// Used by the NFT Fractionalization Pallet.
-	NftFractionalization,
-}
-
 impl pallet_balances::Config for Runtime {
 	type MaxLocks = MaxLocks;
 	type MaxReserves = MaxReserves;
@@ -462,7 +450,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = pallet_balances::weights::SubstrateWeight<Runtime>;
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = HoldReason;
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ConstU32<2>;
 }
 
@@ -1520,7 +1508,6 @@ parameter_types! {
 	pub const ThawThrottle: (Perquintill, BlockNumber) = (Perquintill::from_percent(25), 5);
 	pub Target: Perquintill = Perquintill::zero();
 	pub const NisPalletId: PalletId = PalletId(*b"py/nis  ");
-	pub const NisHoldReason: HoldReason = HoldReason::Nis;
 }
 
 impl pallet_nis::Config for Runtime {
@@ -1544,7 +1531,7 @@ impl pallet_nis::Config for Runtime {
 	type IntakePeriod = IntakePeriod;
 	type MaxIntakeWeight = MaxIntakeWeight;
 	type ThawThrottle = ThawThrottle;
-	type HoldReason = NisHoldReason;
+	type RuntimeHoldReason = RuntimeHoldReason;
 }
 
 parameter_types! {
@@ -1618,7 +1605,6 @@ parameter_types! {
 	pub const NftFractionalizationPalletId: PalletId = PalletId(*b"fraction");
 	pub NewAssetSymbol: BoundedVec<u8, StringLimit> = (*b"FRAC").to_vec().try_into().unwrap();
 	pub NewAssetName: BoundedVec<u8, StringLimit> = (*b"Frac").to_vec().try_into().unwrap();
-	pub const NftFractionalizationHoldReason: HoldReason = HoldReason::NftFractionalization;
 }
 
 impl pallet_nft_fractionalization::Config for Runtime {
@@ -1636,7 +1622,7 @@ impl pallet_nft_fractionalization::Config for Runtime {
 	type Nfts = Nfts;
 	type PalletId = NftFractionalizationPalletId;
 	type WeightInfo = pallet_nft_fractionalization::weights::SubstrateWeight<Runtime>;
-	type HoldReason = NftFractionalizationHoldReason;
+	type RuntimeHoldReason = RuntimeHoldReason;
 	#[cfg(feature = "runtime-benchmarks")]
 	type BenchmarkHelper = ();
 }

substrate/client/executor/benches/bench.rs

@@ -25,7 +25,6 @@ use sc_executor_common::{
 };
 use sc_executor_wasmtime::InstantiationStrategy;
 use sc_runtime_test::wasm_binary_unwrap as test_runtime;
-use sp_wasm_interface::HostFunctions as _;
 use std::sync::{
 	atomic::{AtomicBool, AtomicUsize, Ordering},
 	Arc,

substrate/frame/alliance/src/mock.rs

@@ -89,7 +89,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/asset-rate/src/mock.rs

@@ -77,7 +77,7 @@ impl pallet_balances::Config for Test {
 	type MaxLocks = ();
 	type MaxReserves = ();
 	type ReserveIdentifier = [u8; 8];
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type FreezeIdentifier = ();
 	type MaxHolds = ();
 	type MaxFreezes = ();

substrate/frame/assets/src/mock.rs

@@ -87,7 +87,7 @@ impl pallet_balances::Config for Test {
 	type MaxLocks = ();
 	type MaxReserves = ();
 	type ReserveIdentifier = [u8; 8];
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type FreezeIdentifier = ();
 	type MaxHolds = ();
 	type MaxFreezes = ();

substrate/frame/atomic-swap/src/tests.rs

@@ -64,7 +64,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/babe/src/mock.rs

@@ -145,7 +145,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/balances/src/impl_fungible.rs

@@ -207,7 +207,7 @@ impl<T: Config<I>, I: 'static> fungible::Mutate<T::AccountId> for Pallet<T, I> {
 impl<T: Config<I>, I: 'static> fungible::MutateHold<T::AccountId> for Pallet<T, I> {}
 
 impl<T: Config<I>, I: 'static> fungible::InspectHold<T::AccountId> for Pallet<T, I> {
-	type Reason = T::HoldIdentifier;
+	type Reason = T::RuntimeHoldReason;
 
 	fn total_balance_on_hold(who: &T::AccountId) -> T::Balance {
 		Self::account(who).reserved

substrate/frame/balances/src/lib.rs

@@ -257,8 +257,8 @@ pub mod pallet {
 		/// Use of reserves is deprecated in favour of holds. See `https://github.com/paritytech/substrate/pull/12951/`
 		type ReserveIdentifier: Parameter + Member + MaxEncodedLen + Ord + Copy;
 
-		/// The ID type for holds.
-		type HoldIdentifier: Parameter + Member + MaxEncodedLen + Ord + Copy;
+		/// The overarching hold reason.
+		type RuntimeHoldReason: Parameter + Member + MaxEncodedLen + Ord + Copy;
 
 		/// The ID type for freezes.
 		type FreezeIdentifier: Parameter + Member + MaxEncodedLen + Ord + Copy;
@@ -437,7 +437,7 @@ pub mod pallet {
 		_,
 		Blake2_128Concat,
 		T::AccountId,
-		BoundedVec<IdAmount<T::HoldIdentifier, T::Balance>, T::MaxHolds>,
+		BoundedVec<IdAmount<T::RuntimeHoldReason, T::Balance>, T::MaxHolds>,
 		ValueQuery,
 	>;
 

substrate/frame/balances/src/tests/mod.rs

@@ -137,7 +137,7 @@ impl Config for Test {
 	type MaxReserves = ConstU32<2>;
 	type ReserveIdentifier = TestId;
 	type WeightInfo = ();
-	type HoldIdentifier = TestId;
+	type RuntimeHoldReason = TestId;
 	type FreezeIdentifier = TestId;
 	type MaxFreezes = ConstU32<2>;
 	type MaxHolds = ConstU32<2>;

substrate/frame/beefy/src/mock.rs

@@ -161,7 +161,7 @@ impl pallet_balances::Config for Test {
 	type ExistentialDeposit = ConstU128<1>;
 	type AccountStore = System;
 	type WeightInfo = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();

substrate/frame/bounties/src/tests.rs

@@ -102,7 +102,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/child-bounties/src/tests.rs

@@ -105,7 +105,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/contracts/src/tests.rs

@@ -322,7 +322,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/conviction-voting/src/tests.rs

@@ -94,7 +94,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/democracy/src/tests.rs

@@ -146,7 +146,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/election-provider-multi-phase/src/mock.rs

@@ -256,7 +256,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/election-provider-multi-phase/test-staking-e2e/src/mock.rs

@@ -126,7 +126,7 @@ impl pallet_balances::Config for Runtime {
 	type AccountStore = System;
 	type MaxHolds = ConstU32<1>;
 	type MaxFreezes = traits::ConstU32<1>;
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type FreezeIdentifier = ();
 	type WeightInfo = ();
 }

substrate/frame/elections-phragmen/src/lib.rs

@@ -1352,7 +1352,7 @@ mod tests {
 		type WeightInfo = ();
 		type FreezeIdentifier = ();
 		type MaxFreezes = ();
-		type HoldIdentifier = ();
+		type RuntimeHoldReason = ();
 		type MaxHolds = ();
 	}
 

substrate/frame/examples/basic/src/tests.rs

@@ -89,7 +89,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/examples/dev-mode/src/tests.rs

@@ -83,7 +83,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ();
 }
 

substrate/frame/executive/src/lib.rs

@@ -886,7 +886,7 @@ mod tests {
 		type WeightInfo = ();
 		type FreezeIdentifier = ();
 		type MaxFreezes = ConstU32<1>;
-		type HoldIdentifier = ();
+		type RuntimeHoldReason = ();
 		type MaxHolds = ConstU32<1>;
 	}
 

substrate/frame/fast-unstake/src/mock.rs

@@ -91,7 +91,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/grandpa/src/mock.rs

@@ -144,7 +144,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/identity/src/tests.rs

@@ -87,7 +87,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/indices/src/mock.rs

@@ -78,7 +78,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/lottery/src/mock.rs

@@ -91,7 +91,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/multisig/src/tests.rs

@@ -87,7 +87,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/nft-fractionalization/src/lib.rs

@@ -63,8 +63,8 @@ pub mod pallet {
 		sp_runtime::traits::{AccountIdConversion, StaticLookup},
 		traits::{
 			fungible::{
-				hold::{Inspect as HoldInspectFungible, Mutate as HoldMutateFungible},
-				Inspect as InspectFungible, Mutate as MutateFungible,
+				hold::Mutate as HoldMutateFungible, Inspect as InspectFungible,
+				Mutate as MutateFungible,
 			},
 			fungibles::{
 				metadata::{MetadataDeposit, Mutate as MutateMetadata},
@@ -96,11 +96,10 @@ pub mod pallet {
 		/// The currency mechanism, used for paying for deposits.
 		type Currency: InspectFungible<Self::AccountId>
 			+ MutateFungible<Self::AccountId>
-			+ HoldInspectFungible<Self::AccountId>
-			+ HoldMutateFungible<Self::AccountId>;
+			+ HoldMutateFungible<Self::AccountId, Reason = Self::RuntimeHoldReason>;
 
-		#[pallet::constant]
-		type HoldReason: Get<<Self::Currency as HoldInspectFungible<Self::AccountId>>::Reason>;
+		/// Overarching hold reason.
+		type RuntimeHoldReason: From<HoldReason>;
 
 		/// The deposit paid by the user locking an NFT. The deposit is returned to the original NFT
 		/// owner when the asset is unified and the NFT is unlocked.
@@ -201,6 +200,14 @@ pub mod pallet {
 		NftNotFractionalized,
 	}
 
+	/// A reason for the pallet placing a hold on funds.
+	#[pallet::composite_enum]
+	pub enum HoldReason {
+		/// Reserved for a fractionalized NFT.
+		#[codec(index = 0)]
+		Fractionalized,
+	}
+
 	#[pallet::call]
 	impl<T: Config> Pallet<T> {
 		/// Lock the NFT and mint a new fungible asset.
@@ -239,7 +246,7 @@ pub mod pallet {
 
 			let pallet_account = Self::get_pallet_account();
 			let deposit = T::Deposit::get();
-			T::Currency::hold(&T::HoldReason::get(), &nft_owner, deposit)?;
+			T::Currency::hold(&HoldReason::Fractionalized.into(), &nft_owner, deposit)?;
 			Self::do_lock_nft(nft_collection_id, nft_id)?;
 			Self::do_create_asset(asset_id.clone(), pallet_account.clone())?;
 			Self::do_mint_asset(asset_id.clone(), &beneficiary, fractions)?;
@@ -303,7 +310,12 @@ pub mod pallet {
 				let asset_creator = details.asset_creator;
 				Self::do_burn_asset(asset_id.clone(), &who, details.fractions)?;
 				Self::do_unlock_nft(nft_collection_id, nft_id, &beneficiary)?;
-				T::Currency::release(&T::HoldReason::get(), &asset_creator, deposit, BestEffort)?;
+				T::Currency::release(
+					&HoldReason::Fractionalized.into(),
+					&asset_creator,
+					deposit,
+					BestEffort,
+				)?;
 
 				Self::deposit_event(Event::NftUnified {
 					nft_collection: nft_collection_id,

substrate/frame/nft-fractionalization/src/mock.rs

@@ -20,7 +20,6 @@
 use super::*;
 use crate as pallet_nft_fractionalization;
 
-use codec::{Decode, Encode, MaxEncodedLen};
 use frame_support::{
 	construct_runtime, parameter_types,
 	traits::{AsEnsureOriginWithArg, ConstU32, ConstU64},
@@ -28,7 +27,6 @@ use frame_support::{
 };
 use frame_system::EnsureSigned;
 use pallet_nfts::PalletFeatures;
-use scale_info::TypeInfo;
 use sp_core::H256;
 use sp_runtime::{
 	testing::Header,
@@ -83,13 +81,6 @@ impl frame_system::Config for Test {
 	type MaxConsumers = ConstU32<16>;
 }
 
-#[derive(
-	Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, Debug, TypeInfo,
-)]
-pub enum HoldIdentifier {
-	NftFractionalization,
-}
-
 impl pallet_balances::Config for Test {
 	type Balance = u64;
 	type DustRemoval = ();
@@ -100,7 +91,7 @@ impl pallet_balances::Config for Test {
 	type MaxLocks = ();
 	type MaxReserves = ConstU32<50>;
 	type ReserveIdentifier = [u8; 8];
-	type HoldIdentifier = HoldIdentifier;
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ConstU32<1>;
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
@@ -169,7 +160,6 @@ parameter_types! {
 	pub const NftFractionalizationPalletId: PalletId = PalletId(*b"fraction");
 	pub NewAssetSymbol: BoundedVec<u8, StringLimit> = (*b"FRAC").to_vec().try_into().unwrap();
 	pub NewAssetName: BoundedVec<u8, StringLimit> = (*b"Frac").to_vec().try_into().unwrap();
-	pub const HoldReason: HoldIdentifier = HoldIdentifier::NftFractionalization;
 }
 
 impl Config for Test {
@@ -189,7 +179,7 @@ impl Config for Test {
 	type StringLimit = StringLimit;
 	#[cfg(feature = "runtime-benchmarks")]
 	type BenchmarkHelper = ();
-	type HoldReason = HoldReason;
+	type RuntimeHoldReason = RuntimeHoldReason;
 }
 
 // Build genesis storage according to the mock runtime.

substrate/frame/nfts/src/mock.rs

@@ -90,7 +90,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/nicks/src/lib.rs

@@ -297,7 +297,7 @@ mod tests {
 		type WeightInfo = ();
 		type FreezeIdentifier = ();
 		type MaxFreezes = ();
-		type HoldIdentifier = ();
+		type RuntimeHoldReason = ();
 		type MaxHolds = ();
 	}
 

substrate/frame/nis/src/lib.rs

@@ -162,11 +162,7 @@ pub mod pallet {
 	use frame_support::{
 		pallet_prelude::*,
 		traits::{
-			fungible::{
-				self,
-				hold::{Inspect as FunHoldInspect, Mutate as FunHoldMutate},
-				Balanced as FunBalanced,
-			},
+			fungible::{self, hold::Mutate as FunHoldMutate, Balanced as FunBalanced},
 			nonfungible::{Inspect as NftInspect, Transfer as NftTransfer},
 			tokens::{
 				Fortitude::Polite,
@@ -216,13 +212,10 @@ pub mod pallet {
 		type Currency: FunInspect<Self::AccountId, Balance = Self::CurrencyBalance>
 			+ FunMutate<Self::AccountId>
 			+ FunBalanced<Self::AccountId>
-			+ FunHoldInspect<Self::AccountId>
-			+ FunHoldMutate<Self::AccountId>;
+			+ FunHoldMutate<Self::AccountId, Reason = Self::RuntimeHoldReason>;
 
-		/// The identifier of the hold reason.
-
-		#[pallet::constant]
-		type HoldReason: Get<<Self::Currency as FunHoldInspect<Self::AccountId>>::Reason>;
+		/// Overarching hold reason.
+		type RuntimeHoldReason: From<HoldReason>;
 
 		/// Just the `Currency::Balance` type; we have this item to allow us to constrain it to
 		/// `From<u64>`.
@@ -569,14 +562,14 @@ pub mod pallet {
 				|q| -> Result<(u32, BalanceOf<T>), DispatchError> {
 					let queue_full = q.len() == T::MaxQueueLen::get() as usize;
 					ensure!(!queue_full || q[0].amount < amount, Error::<T>::BidTooLow);
-					T::Currency::hold(&T::HoldReason::get(), &who, amount)?;
+					T::Currency::hold(&HoldReason::NftReceipt.into(), &who, amount)?;
 
 					// queue is <Ordered: Lowest ... Highest><Fifo: Last ... First>
 					let mut bid = Bid { amount, who: who.clone() };
 					let net = if queue_full {
 						sp_std::mem::swap(&mut q[0], &mut bid);
 						let _ = T::Currency::release(
-							&T::HoldReason::get(),
+							&HoldReason::NftReceipt.into(),
 							&bid.who,
 							bid.amount,
 							BestEffort,
@@ -637,7 +630,7 @@ pub mod pallet {
 			queue.remove(pos);
 			let new_len = queue.len() as u32;
 
-			T::Currency::release(&T::HoldReason::get(), &bid.who, bid.amount, BestEffort)?;
+			T::Currency::release(&HoldReason::NftReceipt.into(), &bid.who, bid.amount, BestEffort)?;
 
 			Queues::<T>::insert(duration, queue);
 			QueueTotals::<T>::mutate(|qs| {
@@ -729,7 +722,7 @@ pub mod pallet {
 			let dropped = receipt.proportion.is_zero();
 
 			if amount > on_hold {
-				T::Currency::release(&T::HoldReason::get(), &who, on_hold, Exact)?;
+				T::Currency::release(&HoldReason::NftReceipt.into(), &who, on_hold, Exact)?;
 				let deficit = amount - on_hold;
 				// Try to transfer deficit from pot to receipt owner.
 				summary.receipts_on_hold.saturating_reduce(on_hold);
@@ -744,7 +737,7 @@ pub mod pallet {
 					// Transfer excess of `on_hold` to the pot if we have now fully compensated for
 					// the receipt.
 					T::Currency::transfer_on_hold(
-						&T::HoldReason::get(),
+						&HoldReason::NftReceipt.into(),
 						&who,
 						&our_account,
 						on_hold,
@@ -760,7 +753,7 @@ pub mod pallet {
 					)?;
 					summary.receipts_on_hold.saturating_reduce(on_hold);
 				}
-				T::Currency::release(&T::HoldReason::get(), &who, amount, Exact)?;
+				T::Currency::release(&HoldReason::NftReceipt.into(), &who, amount, Exact)?;
 			}
 
 			if dropped {
@@ -852,7 +845,7 @@ pub mod pallet {
 			ensure!(owner == who, Error::<T>::NotOwner);
 
 			// Unreserve and transfer the funds to the pot.
-			let reason = T::HoldReason::get();
+			let reason = HoldReason::NftReceipt.into();
 			let us = Self::account_id();
 			T::Currency::transfer_on_hold(&reason, &who, &us, on_hold, Exact, Free, Polite)
 				.map_err(|_| Error::<T>::Unfunded)?;
@@ -903,7 +896,7 @@ pub mod pallet {
 			)?;
 
 			// Transfer the funds from the pot to the owner and reserve
-			let reason = T::HoldReason::get();
+			let reason = HoldReason::NftReceipt.into();
 			let us = Self::account_id();
 			T::Currency::transfer_and_hold(&reason, &us, &who, amount, Exact, Expendable, Polite)?;
 
@@ -959,7 +952,7 @@ pub mod pallet {
 			let mut item = Receipts::<T>::get(index).ok_or(TokenError::UnknownAsset)?;
 			let (owner, on_hold) = item.owner.take().ok_or(Error::<T>::AlreadyCommunal)?;
 
-			let reason = T::HoldReason::get();
+			let reason = HoldReason::NftReceipt.into();
 			T::Currency::transfer_on_hold(&reason, &owner, dest, on_hold, Exact, OnHold, Polite)?;
 
 			item.owner = Some((dest.clone(), on_hold));

substrate/frame/nis/src/mock.rs

@@ -19,7 +19,6 @@
 
 use crate::{self as pallet_nis, Perquintill, WithMaximumOf};
 
-use codec::{Decode, Encode, MaxEncodedLen};
 use frame_support::{
 	ord_parameter_types, parameter_types,
 	traits::{
@@ -30,7 +29,6 @@ use frame_support::{
 	PalletId,
 };
 use pallet_balances::{Instance1, Instance2};
-use scale_info::TypeInfo;
 use sp_core::{ConstU128, H256};
 use sp_runtime::{
 	testing::Header,
@@ -95,17 +93,10 @@ impl pallet_balances::Config<Instance1> for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = HoldIdentifier;
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ConstU32<1>;
 }
 
-#[derive(
-	Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, Debug, TypeInfo,
-)]
-pub enum HoldIdentifier {
-	Nis,
-}
-
 impl pallet_balances::Config<Instance2> for Test {
 	type Balance = u128;
 	type DustRemoval = ();
@@ -122,7 +113,7 @@ impl pallet_balances::Config<Instance2> for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 
@@ -133,7 +124,6 @@ parameter_types! {
 	pub const MinReceipt: Perquintill = Perquintill::from_percent(1);
 	pub const ThawThrottle: (Perquintill, u64) = (Perquintill::from_percent(25), 5);
 	pub static MaxIntakeWeight: Weight = Weight::from_parts(2_000_000_000_000, 0);
-	pub const HoldReason: HoldIdentifier = HoldIdentifier::Nis;
 }
 
 ord_parameter_types! {
@@ -161,7 +151,7 @@ impl pallet_nis::Config for Test {
 	type MaxIntakeWeight = MaxIntakeWeight;
 	type MinReceipt = MinReceipt;
 	type ThawThrottle = ThawThrottle;
-	type HoldReason = HoldReason;
+	type RuntimeHoldReason = RuntimeHoldReason;
 }
 
 // This function basically just builds a genesis storage key/value store according to

substrate/frame/nomination-pools/benchmarking/src/mock.rs

@@ -77,7 +77,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/nomination-pools/src/mock.rs

@@ -206,7 +206,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/nomination-pools/test-staking/src/mock.rs

@@ -88,7 +88,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/offences/benchmarking/src/mock.rs

@@ -76,7 +76,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/preimage/src/mock.rs

@@ -86,7 +86,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/proxy/src/tests.rs

@@ -90,7 +90,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 impl pallet_utility::Config for Test {

substrate/frame/recovery/src/mock.rs

@@ -88,7 +88,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/referenda/src/mock.rs

@@ -122,7 +122,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/root-offences/src/mock.rs

@@ -123,7 +123,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/scored-pool/src/mock.rs

@@ -93,7 +93,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/session/benchmarking/src/mock.rs

@@ -86,7 +86,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/society/src/mock.rs

@@ -95,7 +95,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/staking/src/mock.rs

@@ -159,7 +159,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/state-trie-migration/src/lib.rs

@@ -1130,7 +1130,7 @@ mod mock {
 		type WeightInfo = ();
 		type FreezeIdentifier = ();
 		type MaxFreezes = ();
-		type HoldIdentifier = ();
+		type RuntimeHoldReason = ();
 		type MaxHolds = ();
 	}
 

substrate/frame/statement/src/mock.rs

@@ -91,7 +91,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ();
 }
 

substrate/frame/tips/src/tests.rs

@@ -99,7 +99,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/transaction-payment/asset-tx-payment/src/mock.rs

@@ -122,7 +122,7 @@ impl pallet_balances::Config for Runtime {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/transaction-payment/src/mock.rs

@@ -115,7 +115,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/transaction-storage/src/mock.rs

@@ -86,7 +86,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/treasury/src/tests.rs

@@ -92,7 +92,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/uniques/src/mock.rs

@@ -84,7 +84,7 @@ impl pallet_balances::Config for Test {
 	type ReserveIdentifier = [u8; 8];
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/utility/src/tests.rs

@@ -188,7 +188,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/frame/vesting/src/mock.rs

@@ -82,7 +82,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 parameter_types! {

substrate/frame/whitelist/src/mock.rs

@@ -88,7 +88,7 @@ impl pallet_balances::Config for Test {
 	type WeightInfo = ();
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = ();
 	type MaxHolds = ();
 }
 

substrate/test-utils/runtime/src/lib.rs

@@ -394,7 +394,7 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = pallet_balances::weights::SubstrateWeight<Runtime>;
 	type FreezeIdentifier = ();
 	type MaxFreezes = ();
-	type HoldIdentifier = ();
+	type RuntimeHoldReason = RuntimeHoldReason;
 	type MaxHolds = ConstU32<1>;
 }