NFT Fractionalization on Westmint (#2600)

* NFT Fractionalization on Westmint

* Typos

* One more typo

* Undo Cargo.lock

* Point to master

* Referense the first instance of the assets pallet

* Update cargo.lock

---------

Co-authored-by: parity-processbot <>

parachains/runtimes/assets/westmint/Cargo.toml

@@ -26,6 +26,7 @@ pallet-aura = { git = "https://github.com/paritytech/substrate", default-feature
 pallet-authorship = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
 pallet-balances = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
 pallet-multisig = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+pallet-nft-fractionalization = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
 pallet-nfts = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
 pallet-nfts-runtime-api = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
 pallet-proxy = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
@@ -91,6 +92,7 @@ runtime-benchmarks = [
 	"pallet-assets/runtime-benchmarks",
 	"pallet-balances/runtime-benchmarks",
 	"pallet-multisig/runtime-benchmarks",
+	"pallet-nft-fractionalization/runtime-benchmarks",
 	"pallet-nfts/runtime-benchmarks",
 	"pallet-proxy/runtime-benchmarks",
 	"pallet-timestamp/runtime-benchmarks",
@@ -121,6 +123,7 @@ try-runtime = [
 	"pallet-balances/try-runtime",
 	"pallet-collator-selection/try-runtime",
 	"pallet-multisig/try-runtime",
+	"pallet-nft-fractionalization/try-runtime",
 	"pallet-nfts/try-runtime",
 	"pallet-proxy/try-runtime",
 	"pallet-session/try-runtime",
@@ -145,6 +148,7 @@ std = [
 	"pallet-authorship/std",
 	"pallet-balances/std",
 	"pallet-multisig/std",
+	"pallet-nft-fractionalization/std",
 	"pallet-nfts/std",
 	"pallet-nfts-runtime-api/std",
 	"pallet-proxy/std",

parachains/runtimes/assets/westmint/src/lib.rs

@@ -54,7 +54,7 @@ use frame_support::{
 		InstanceFilter,
 	},
 	weights::{ConstantMultiplier, Weight},
-	PalletId, RuntimeDebug,
+	BoundedVec, PalletId, RuntimeDebug,
 };
 use frame_system::{
 	limits::{BlockLength, BlockWeights},
@@ -68,6 +68,7 @@ use parachains_common::{
 	Index, Signature, AVERAGE_ON_INITIALIZE_RATIO, DAYS, HOURS, MAXIMUM_BLOCK_WEIGHT,
 	NORMAL_DISPATCH_RATIO, SLOT_DURATION,
 };
+use scale_info::TypeInfo;
 use xcm_config::{
 	ForeignAssetsConvertedConcreteId, TrustBackedAssetsConvertedConcreteId, WestendLocation,
 	XcmConfig, XcmOriginToTransactDispatchOrigin,
@@ -179,6 +180,15 @@ parameter_types! {
 	pub const ExistentialDeposit: Balance = EXISTENTIAL_DEPOSIT;
 }
 
+/// A reason for placing a hold on funds.
+#[derive(
+	Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, Debug, TypeInfo,
+)]
+pub enum HoldReason {
+	/// Used by the NFT Fractionalization Pallet.
+	NftFractionalization,
+}
+
 impl pallet_balances::Config for Runtime {
 	type MaxLocks = ConstU32<50>;
 	/// The type for recording an account's balance.
@@ -191,9 +201,9 @@ impl pallet_balances::Config for Runtime {
 	type WeightInfo = weights::pallet_balances::WeightInfo<Runtime>;
 	type MaxReserves = ConstU32<50>;
 	type ReserveIdentifier = [u8; 8];
-	type HoldIdentifier = ();
+	type HoldIdentifier = HoldReason;
 	type FreezeIdentifier = ();
-	type MaxHolds = ConstU32<0>;
+	type MaxHolds = ConstU32<1>;
 	type MaxFreezes = ConstU32<0>;
 }
 
@@ -376,6 +386,7 @@ impl InstanceFilter<RuntimeCall> for ProxyType {
 				c,
 				RuntimeCall::Balances { .. } |
 					RuntimeCall::Assets { .. } |
+					RuntimeCall::NftFractionalization { .. } |
 					RuntimeCall::Nfts { .. } |
 					RuntimeCall::Uniques { .. }
 			),
@@ -391,6 +402,7 @@ impl InstanceFilter<RuntimeCall> for ProxyType {
 					RuntimeCall::Assets { .. } |
 						RuntimeCall::Utility { .. } |
 						RuntimeCall::Multisig { .. } |
+						RuntimeCall::NftFractionalization { .. } |
 						RuntimeCall::Nfts { .. } | RuntimeCall::Uniques { .. }
 				)
 			},
@@ -624,6 +636,33 @@ impl pallet_uniques::Config for Runtime {
 	type Locker = ();
 }
 
+parameter_types! {
+	pub const NftFractionalizationPalletId: PalletId = PalletId(*b"fraction");
+	pub NewAssetSymbol: BoundedVec<u8, AssetsStringLimit> = (*b"FRAC").to_vec().try_into().unwrap();
+	pub NewAssetName: BoundedVec<u8, AssetsStringLimit> = (*b"Frac").to_vec().try_into().unwrap();
+	pub const NftFractionalizationHoldReason: HoldReason = HoldReason::NftFractionalization;
+}
+
+impl pallet_nft_fractionalization::Config for Runtime {
+	type RuntimeEvent = RuntimeEvent;
+	type Deposit = AssetDeposit;
+	type Currency = Balances;
+	type NewAssetSymbol = NewAssetSymbol;
+	type NewAssetName = NewAssetName;
+	type StringLimit = AssetsStringLimit;
+	type NftCollectionId = <Self as pallet_nfts::Config>::CollectionId;
+	type NftId = <Self as pallet_nfts::Config>::ItemId;
+	type AssetBalance = <Self as pallet_balances::Config>::Balance;
+	type AssetId = <Self as pallet_assets::Config<TrustBackedAssetsInstance>>::AssetId;
+	type Assets = Assets;
+	type Nfts = Nfts;
+	type PalletId = NftFractionalizationPalletId;
+	type WeightInfo = pallet_nft_fractionalization::weights::SubstrateWeight<Runtime>;
+	type HoldReason = NftFractionalizationHoldReason;
+	#[cfg(feature = "runtime-benchmarks")]
+	type BenchmarkHelper = ();
+}
+
 parameter_types! {
 	pub NftsPalletFeatures: PalletFeatures = PalletFeatures::all_enabled();
 	pub const NftsMaxDeadlineDuration: BlockNumber = 12 * 30 * DAYS;
@@ -708,6 +747,7 @@ construct_runtime!(
 		Uniques: pallet_uniques::{Pallet, Call, Storage, Event<T>} = 51,
 		Nfts: pallet_nfts::{Pallet, Call, Storage, Event<T>} = 52,
 		ForeignAssets: pallet_assets::<Instance2>::{Pallet, Call, Storage, Event<T>} = 53,
+		NftFractionalization: pallet_nft_fractionalization::{Pallet, Call, Storage, Event<T>} = 54,
 	}
 );
 
@@ -736,7 +776,7 @@ pub type UncheckedExtrinsic =
 /// Extrinsic type that has already been checked.
 pub type CheckedExtrinsic = generic::CheckedExtrinsic<AccountId, RuntimeCall, SignedExtra>;
 /// Migrations to apply on runtime upgrade.
-pub type Migrations = (pallet_nfts::migration::v1::MigrateToV1<Runtime>,);
+pub type Migrations = ();
 
 /// Executive: handles dispatch to the various modules.
 pub type Executive = frame_executive::Executive<
@@ -760,6 +800,7 @@ mod benches {
 		[pallet_assets, ForeignAssets]
 		[pallet_balances, Balances]
 		[pallet_multisig, Multisig]
+		[pallet_nft_fractionalization, NftFractionalization]
 		[pallet_nfts, Nfts]
 		[pallet_proxy, Proxy]
 		[pallet_session, SessionBench::<Runtime>]

parachains/runtimes/assets/westmint/src/weights/mod.rs

@@ -6,6 +6,7 @@ pub mod pallet_assets;
 pub mod pallet_balances;
 pub mod pallet_collator_selection;
 pub mod pallet_multisig;
+pub mod pallet_nft_fractionalization;
 pub mod pallet_nfts;
 pub mod pallet_proxy;
 pub mod pallet_session;

parachains/runtimes/assets/westmint/src/weights/pallet_nft_fractionalization.rs

@@ -0,0 +1,63 @@
+// Copyright Parity Technologies (UK) Ltd.
+// This file is part of Cumulus.
+
+// Cumulus is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Cumulus is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Cumulus.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Autogenerated weights for `pallet_nfts`
+//!
+//! THIS FILE WAS AUTO-GENERATED USING THE SUBSTRATE BENCHMARK CLI VERSION 4.0.0-dev
+//! DATE: 2023-05-05, STEPS: `50`, REPEAT: `20`, LOW RANGE: `[]`, HIGH RANGE: `[]`
+//! WORST CASE MAP SIZE: `1000000`
+//! HOSTNAME: `bm6`, CPU: `Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz`
+//! EXECUTION: Some(Wasm), WASM-EXECUTION: Compiled, CHAIN: Some("westmint-dev"), DB CACHE: 1024
+
+// Executed Command:
+// ./artifacts/polkadot-parachain
+// benchmark
+// pallet
+// --chain=westmint-dev
+// --execution=wasm
+// --wasm-execution=compiled
+// --pallet=pallet_nft_fractionalization
+// --extrinsic=*
+// --steps=50
+// --repeat=20
+// --json
+// --header=./file_header.txt
+// --output=./parachains/runtimes/assets/westmint/src/weights/pallet_nft_fractionalization.rs
+
+#![cfg_attr(rustfmt, rustfmt_skip)]
+#![allow(unused_parens)]
+#![allow(unused_imports)]
+#![allow(missing_docs)]
+
+use frame_support::{traits::Get, weights::Weight};
+use core::marker::PhantomData;
+
+/// Weight functions for `pallet_nfts`.
+pub struct WeightInfo<T>(PhantomData<T>);
+impl<T: frame_system::Config> pallet_nft_fractionalization::WeightInfo for WeightInfo<T> {
+	fn fractionalize() -> Weight {
+		// Minimum execution time: 44_312 nanoseconds.
+		Weight::from_parts(25_147_000, 3549)
+			.saturating_add(T::DbWeight::get().reads(2_u64))
+			.saturating_add(T::DbWeight::get().writes(5_u64))
+	}
+	fn unify() -> Weight {
+		// Minimum execution time: 31_654 nanoseconds.
+		Weight::from_parts(25_147_000, 3549)
+			.saturating_add(T::DbWeight::get().reads(2_u64))
+			.saturating_add(T::DbWeight::get().writes(5_u64))
+	}
+}

parachains/runtimes/assets/westmint/src/xcm_config.rs

@@ -271,6 +271,9 @@ impl Contains<RuntimeCall> for SafeCallFilter {
 					pallet_assets::Call::transfer_approved { .. } |
 					pallet_assets::Call::touch { .. } |
 					pallet_assets::Call::refund { .. },
+			) | RuntimeCall::NftFractionalization(
+				pallet_nft_fractionalization::Call::fractionalize { .. } |
+					pallet_nft_fractionalization::Call::unify { .. },
 			) | RuntimeCall::Nfts(
 				pallet_nfts::Call::create { .. } |
 					pallet_nfts::Call::force_create { .. } |