pallet-asset-conversion: Decoupling Native Currency Dependancy (#2031)

closes https://github.com/paritytech/polkadot-sdk/issues/1842

Decoupling Pallet from the Concept of Native Currency

Currently, the pallet is intrinsically linked with the concept of native
currency, requiring users to provide implementations of the
`fungible::*` and `fungibles::*` traits to interact with native and non
native assets. This incapsulates some non-related to the pallet
complexity and makes it less adaptable in contexts where the native
currency concept is absent.

With this PR, the dependence on `fungible::*` for liquidity-supplying
assets has been removed. Instead, the native and non-native currencies'
handling is now overseen by a single type that implements the
`fungibles::*` traits. To simplify this integration, types have been
introduced to facilitate the creation of a union between `fungible::*`
and `fungibles::*` implementations, producing a unified `fungibles::*`
type.

One of the reasons driving these changes is the ambition to create a
more user-friendly API for the `SwapCredit` implementation. Given that
it interacts with two distinct credit types from `fungible` and
`fungibles`, a unified type was introduced. Clients now manage potential
conversion failures for those credit types. In certain contexts, it's
vital to guarantee that operations are fail-safe, like in this impl -
[PR](https://github.com/paritytech/polkadot-sdk/pull/1845), place in
[code](https://github.com/paritytech/polkadot-sdk/blob/20b85a5fada8f55c98ba831964f5866ffeadf4da/cumulus/primitives/utility/src/lib.rs#L429).

Additional Updates:
- abstracted the pool ID and its account derivation logic via trait
bounds, along with common implementation offerings;
- removed `inc_providers` on a pool creation for the pool account;
- benchmarks:
-- swap complexity is N, not const;
-- removed `From<u128> + Into<u128>` bound from `T::Balance`;
-- removed swap/liquidity/.. amount constants, resolve them dynamically
based on pallet configuration;
-- migrated to v2 API;
- `OnUnbalanced` handler for the pool creation fee, replacing direct
transfers to a specified account ID;
- renamed `MultiAssetId` to `AssetKind` aligning with naming across
frame crates;

related PRs:
- (depends) https://github.com/paritytech/polkadot-sdk/pull/1677
- (caused) https://github.com/paritytech/polkadot-sdk/pull/2033
- (caused) https://github.com/paritytech/polkadot-sdk/pull/1876

---------

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: Liam Aharon <liam.aharon@hotmail.com>

cumulus/parachains/runtimes/assets/asset-hub-westend/src/lib.rs

@@ -27,11 +27,8 @@ include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));
 mod weights;
 pub mod xcm_config;
 
-use crate::xcm_config::{
-	LocalAndForeignAssetsMultiLocationMatcher, TrustBackedAssetsPalletLocation,
-};
 use assets_common::{
-	local_and_foreign_assets::{LocalAndForeignAssets, MultiLocationConverter},
+	local_and_foreign_assets::{LocalFromLeft, TargetFromLeft},
 	AssetIdForTrustBackedAssetsConvert,
 };
 use codec::{Decode, Encode, MaxEncodedLen};
@@ -43,8 +40,10 @@ use frame_support::{
 	genesis_builder_helper::{build_config, create_default_config},
 	ord_parameter_types, parameter_types,
 	traits::{
-		tokens::nonfungibles_v2::Inspect, AsEnsureOriginWithArg, ConstBool, ConstU128, ConstU32,
-		ConstU64, ConstU8, Equals, InstanceFilter, TransformOrigin,
+		fungible, fungibles,
+		tokens::{imbalance::ResolveAssetTo, nonfungibles_v2::Inspect},
+		AsEnsureOriginWithArg, ConstBool, ConstU128, ConstU32, ConstU64, ConstU8, Equals,
+		InstanceFilter, TransformOrigin,
 	},
 	weights::{ConstantMultiplier, Weight},
 	BoundedVec, PalletId,
@@ -80,7 +79,8 @@ use sp_version::RuntimeVersion;
 use xcm::opaque::v3::MultiLocation;
 use xcm_config::{
 	ForeignAssetsConvertedConcreteId, PoolAssetsConvertedConcreteId,
-	TrustBackedAssetsConvertedConcreteId, WestendLocation, XcmOriginToTransactDispatchOrigin,
+	TrustBackedAssetsConvertedConcreteId, TrustBackedAssetsPalletLocation, WestendLocation,
+	XcmOriginToTransactDispatchOrigin,
 };
 
 #[cfg(any(feature = "std", test))]
@@ -262,8 +262,6 @@ impl pallet_assets::Config<TrustBackedAssetsInstance> for Runtime {
 
 parameter_types! {
 	pub const AssetConversionPalletId: PalletId = PalletId(*b"py/ascon");
-	pub const AllowMultiAssetPools: bool = false;
-	// should be non-zero if AllowMultiAssetPools is true, otherwise can be zero
 	pub const LiquidityWithdrawalFee: Permill = Permill::from_percent(0);
 }
 
@@ -297,34 +295,50 @@ impl pallet_assets::Config<PoolAssetsInstance> for Runtime {
 	type BenchmarkHelper = ();
 }
 
+/// Union fungibles implementation for `Assets`` and `ForeignAssets`.
+pub type LocalAndForeignAssets = fungibles::UnionOf<
+	Assets,
+	ForeignAssets,
+	LocalFromLeft<
+		AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation>,
+		AssetIdForTrustBackedAssets,
+	>,
+	MultiLocation,
+	AccountId,
+>;
+
 impl pallet_asset_conversion::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type Balance = Balance;
 	type HigherPrecisionBalance = sp_core::U256;
-	type Currency = Balances;
-	type AssetId = MultiLocation;
-	type Assets = LocalAndForeignAssets<
-		Assets,
-		AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation>,
-		ForeignAssets,
+	type AssetKind = MultiLocation;
+	type Assets = fungible::UnionOf<
+		Balances,
+		LocalAndForeignAssets,
+		TargetFromLeft<WestendLocation>,
+		Self::AssetKind,
+		Self::AccountId,
 	>;
-	type PoolAssets = PoolAssets;
+	type PoolId = (Self::AssetKind, Self::AssetKind);
+	type PoolLocator =
+		pallet_asset_conversion::WithFirstAsset<WestendLocation, AccountId, Self::AssetKind>;
 	type PoolAssetId = u32;
+	type PoolAssets = PoolAssets;
 	type PoolSetupFee = ConstU128<0>; // Asset class deposit fees are sufficient to prevent spam
-	type PoolSetupFeeReceiver = AssetConversionOrigin;
-	type LiquidityWithdrawalFee = LiquidityWithdrawalFee; // should be non-zero if AllowMultiAssetPools is true, otherwise can be zero.
+	type PoolSetupFeeAsset = WestendLocation;
+	type PoolSetupFeeTarget = ResolveAssetTo<AssetConversionOrigin, Self::Assets>;
+	type LiquidityWithdrawalFee = LiquidityWithdrawalFee;
 	type LPFee = ConstU32<3>;
 	type PalletId = AssetConversionPalletId;
-	type AllowMultiAssetPools = AllowMultiAssetPools;
-	type MaxSwapPathLength = ConstU32<4>;
-	type MultiAssetId = MultiLocation;
-	type MultiAssetIdConverter =
-		MultiLocationConverter<WestendLocation, LocalAndForeignAssetsMultiLocationMatcher>;
+	type MaxSwapPathLength = ConstU32<3>;
 	type MintMinLiquidity = ConstU128<100>;
 	type WeightInfo = weights::pallet_asset_conversion::WeightInfo<Runtime>;
 	#[cfg(feature = "runtime-benchmarks")]
-	type BenchmarkHelper =
-		crate::xcm_config::BenchmarkMultiLocationConverter<parachain_info::Pallet<Runtime>>;
+	type BenchmarkHelper = assets_common::benchmarks::AssetPairFactory<
+		WestendLocation,
+		parachain_info::Pallet<Runtime>,
+		xcm_config::AssetsPalletIndex,
+	>;
 }
 
 parameter_types! {
@@ -709,12 +723,9 @@ impl pallet_collator_selection::Config for Runtime {
 
 impl pallet_asset_conversion_tx_payment::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type Fungibles = LocalAndForeignAssets<
-		Assets,
-		AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation>,
-		ForeignAssets,
-	>;
-	type OnChargeAssetTransaction = AssetConversionAdapter<Balances, AssetConversion>;
+	type Fungibles = LocalAndForeignAssets;
+	type OnChargeAssetTransaction =
+		AssetConversionAdapter<Balances, AssetConversion, WestendLocation>;
 }
 
 parameter_types! {
@@ -924,8 +935,6 @@ pub type Migrations = (
 	// unreleased
 	pallet_collator_selection::migration::v1::MigrateToV1<Runtime>,
 	// unreleased
-	migrations::NativeAssetParents0ToParents1Migration<Runtime>,
-	// unreleased
 	pallet_multisig::migrations::v1::MigrateToV1<Runtime>,
 	// unreleased
 	InitStorageVersions,
@@ -1229,7 +1238,7 @@ impl_runtime_apis! {
 		}
 
 		fn get_reserves(asset1: MultiLocation, asset2: MultiLocation) -> Option<(Balance, Balance)> {
-			AssetConversion::get_reserves(&asset1, &asset2).ok()
+			AssetConversion::get_reserves(asset1, asset2).ok()
 		}
 	}
 
@@ -1689,117 +1698,3 @@ cumulus_pallet_parachain_system::register_validate_block! {
 	Runtime = Runtime,
 	BlockExecutor = cumulus_pallet_aura_ext::BlockExecutor::<Runtime, Executive>,
 }
-
-pub mod migrations {
-	use super::*;
-	use frame_support::{
-		pallet_prelude::Get,
-		traits::{
-			fungibles::{Inspect, Mutate},
-			tokens::Preservation,
-			OnRuntimeUpgrade, OriginTrait,
-		},
-	};
-	use parachains_common::impls::AccountIdOf;
-	use sp_runtime::{traits::StaticLookup, Saturating};
-
-	/// Temporary migration because of bug with native asset, it can be removed once applied on
-	/// `AssetHubWestend`. Migrates pools with `MultiLocation { parents: 0, interior: Here }` to
-	/// `MultiLocation { parents: 1, interior: Here }`
-	pub struct NativeAssetParents0ToParents1Migration<T>(sp_std::marker::PhantomData<T>);
-	impl<
-			T: pallet_asset_conversion::Config<MultiAssetId = MultiLocation, AssetId = MultiLocation>,
-		> OnRuntimeUpgrade for NativeAssetParents0ToParents1Migration<T>
-	where
-		<T as pallet_asset_conversion::Config>::PoolAssetId: Into<u32>,
-		AccountIdOf<Runtime>: Into<[u8; 32]>,
-		<T as frame_system::Config>::AccountId:
-			Into<<<T as frame_system::Config>::RuntimeOrigin as OriginTrait>::AccountId>,
-		<<T as frame_system::Config>::Lookup as StaticLookup>::Source:
-			From<<T as frame_system::Config>::AccountId>,
-		sp_runtime::AccountId32: From<<T as frame_system::Config>::AccountId>,
-	{
-		fn on_runtime_upgrade() -> Weight {
-			let invalid_native_asset = MultiLocation { parents: 0, interior: Here };
-			let valid_native_asset = WestendLocation::get();
-
-			let mut reads: u64 = 1;
-			let mut writes: u64 = 0;
-
-			// migrate pools with invalid native asset
-			let pools = pallet_asset_conversion::Pools::<T>::iter().collect::<Vec<_>>();
-			reads.saturating_accrue(1);
-			for (old_pool_id, pool_info) in pools {
-				let old_pool_account =
-					pallet_asset_conversion::Pallet::<T>::get_pool_account(&old_pool_id);
-				reads.saturating_accrue(1);
-				let pool_asset_id = pool_info.lp_token.clone();
-				if old_pool_id.0 != invalid_native_asset {
-					// skip, if ok
-					continue
-				}
-
-				// fix new account
-				let new_pool_id = pallet_asset_conversion::Pallet::<T>::get_pool_id(
-					valid_native_asset,
-					old_pool_id.1,
-				);
-				let new_pool_account =
-					pallet_asset_conversion::Pallet::<T>::get_pool_account(&new_pool_id);
-				frame_system::Pallet::<T>::inc_providers(&new_pool_account);
-				reads.saturating_accrue(2);
-				writes.saturating_accrue(1);
-
-				// move currency
-				let _ = Balances::transfer_all(
-					RuntimeOrigin::signed(sp_runtime::AccountId32::from(old_pool_account.clone())),
-					sp_runtime::AccountId32::from(new_pool_account.clone()).into(),
-					false,
-				);
-				reads.saturating_accrue(2);
-				writes.saturating_accrue(2);
-
-				// move LP token
-				let _ = T::PoolAssets::transfer(
-					pool_asset_id.clone(),
-					&old_pool_account,
-					&new_pool_account,
-					T::PoolAssets::balance(pool_asset_id.clone(), &old_pool_account),
-					Preservation::Expendable,
-				);
-				reads.saturating_accrue(1);
-				writes.saturating_accrue(2);
-
-				// change the ownership of LP token
-				let _ = pallet_assets::Pallet::<Runtime, PoolAssetsInstance>::transfer_ownership(
-					RuntimeOrigin::signed(sp_runtime::AccountId32::from(old_pool_account.clone())),
-					pool_asset_id.into(),
-					sp_runtime::AccountId32::from(new_pool_account.clone()).into(),
-				);
-				reads.saturating_accrue(1);
-				writes.saturating_accrue(2);
-
-				// move LocalOrForeignAssets
-				let _ = T::Assets::transfer(
-					old_pool_id.1,
-					&old_pool_account,
-					&new_pool_account,
-					T::Assets::balance(old_pool_id.1, &old_pool_account),
-					Preservation::Expendable,
-				);
-				reads.saturating_accrue(1);
-				writes.saturating_accrue(2);
-
-				// dec providers for old account
-				let _ = frame_system::Pallet::<T>::dec_providers(&old_pool_account);
-				writes.saturating_accrue(1);
-
-				// change pool key
-				pallet_asset_conversion::Pools::<T>::insert(new_pool_id, pool_info);
-				pallet_asset_conversion::Pools::<T>::remove(old_pool_id);
-			}
-
-			T::DbWeight::get().reads_writes(reads, writes)
-		}
-	}
-}

cumulus/parachains/runtimes/assets/asset-hub-westend/src/weights/pallet_asset_conversion.rs

@@ -16,27 +16,23 @@
 //! Autogenerated weights for `pallet_asset_conversion`
 //!
 //! THIS FILE WAS AUTO-GENERATED USING THE SUBSTRATE BENCHMARK CLI VERSION 4.0.0-dev
-//! DATE: 2023-07-31, STEPS: `50`, REPEAT: `20`, LOW RANGE: `[]`, HIGH RANGE: `[]`
+//! DATE: 2023-10-30, STEPS: `20`, REPEAT: `2`, LOW RANGE: `[]`, HIGH RANGE: `[]`
 //! WORST CASE MAP SIZE: `1000000`
-//! HOSTNAME: `runner-ynta1nyy-project-238-concurrent-0`, CPU: `Intel(R) Xeon(R) CPU @ 2.60GHz`
-//! EXECUTION: ``, WASM-EXECUTION: `Compiled`, CHAIN: `Some("asset-hub-westend-dev")`, DB CACHE: 1024
+//! HOSTNAME: `cob`, CPU: `<UNKNOWN>`
+//! WASM-EXECUTION: `Compiled`, CHAIN: `Some("asset-hub-westend-dev")`, DB CACHE: 1024
 
 // Executed Command:
-// ./target/production/polkadot-parachain
+// ./target/debug/polkadot-parachain
 // benchmark
 // pallet
 // --chain=asset-hub-westend-dev
-// --wasm-execution=compiled
-// --pallet=pallet_asset_conversion
-// --no-storage-info
-// --no-median-slopes
-// --no-min-squares
+// --steps=20
+// --repeat=2
+// --pallet=pallet-asset-conversion
 // --extrinsic=*
-// --steps=50
-// --repeat=20
-// --json
-// --header=./file_header.txt
-// --output=./parachains/runtimes/assets/asset-hub-westend/src/weights/
+// --wasm-execution=compiled
+// --heap-pages=4096
+// --output=./cumulus/parachains/runtimes/assets/asset-hub-westend/src/weights/pallet_asset_conversion.rs
 
 #![cfg_attr(rustfmt, rustfmt_skip)]
 #![allow(unused_parens)]
@@ -51,9 +47,7 @@ pub struct WeightInfo<T>(PhantomData<T>);
 impl<T: frame_system::Config> pallet_asset_conversion::WeightInfo for WeightInfo<T> {
 	/// Storage: `AssetConversion::Pools` (r:1 w:1)
 	/// Proof: `AssetConversion::Pools` (`max_values`: None, `max_size`: Some(1224), added: 3699, mode: `MaxEncodedLen`)
-	/// Storage: UNKNOWN KEY `0x76a2c49709deec21d9c05f96c1f47351` (r:1 w:0)
-	/// Proof: UNKNOWN KEY `0x76a2c49709deec21d9c05f96c1f47351` (r:1 w:0)
-	/// Storage: `System::Account` (r:2 w:1)
+	/// Storage: `System::Account` (r:1 w:1)
 	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Account` (r:1 w:1)
 	/// Proof: `ForeignAssets::Account` (`max_values`: None, `max_size`: Some(732), added: 3207, mode: `MaxEncodedLen`)
@@ -67,22 +61,22 @@ impl<T: frame_system::Config> pallet_asset_conversion::WeightInfo for WeightInfo
 	/// Proof: `PoolAssets::Account` (`max_values`: None, `max_size`: Some(134), added: 2609, mode: `MaxEncodedLen`)
 	fn create_pool() -> Weight {
 		// Proof Size summary in bytes:
-		//  Measured:  `480`
-		//  Estimated: `6196`
-		// Minimum execution time: 90_011_000 picoseconds.
-		Weight::from_parts(92_372_000, 0)
-			.saturating_add(Weight::from_parts(0, 6196))
-			.saturating_add(T::DbWeight::get().reads(9))
+		//  Measured:  `408`
+		//  Estimated: `4689`
+		// Minimum execution time: 922_000_000 picoseconds.
+		Weight::from_parts(1_102_000_000, 0)
+			.saturating_add(Weight::from_parts(0, 4689))
+			.saturating_add(T::DbWeight::get().reads(7))
 			.saturating_add(T::DbWeight::get().writes(7))
 	}
 	/// Storage: `AssetConversion::Pools` (r:1 w:0)
 	/// Proof: `AssetConversion::Pools` (`max_values`: None, `max_size`: Some(1224), added: 3699, mode: `MaxEncodedLen`)
-	/// Storage: `System::Account` (r:1 w:1)
-	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Asset` (r:1 w:1)
 	/// Proof: `ForeignAssets::Asset` (`max_values`: None, `max_size`: Some(808), added: 3283, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Account` (r:2 w:2)
 	/// Proof: `ForeignAssets::Account` (`max_values`: None, `max_size`: Some(732), added: 3207, mode: `MaxEncodedLen`)
+	/// Storage: `System::Account` (r:1 w:1)
+	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
 	/// Storage: `PoolAssets::Asset` (r:1 w:1)
 	/// Proof: `PoolAssets::Asset` (`max_values`: None, `max_size`: Some(210), added: 2685, mode: `MaxEncodedLen`)
 	/// Storage: `PoolAssets::Account` (r:2 w:2)
@@ -91,34 +85,32 @@ impl<T: frame_system::Config> pallet_asset_conversion::WeightInfo for WeightInfo
 		// Proof Size summary in bytes:
 		//  Measured:  `1117`
 		//  Estimated: `7404`
-		// Minimum execution time: 153_484_000 picoseconds.
-		Weight::from_parts(155_465_000, 0)
+		// Minimum execution time: 1_597_000_000 picoseconds.
+		Weight::from_parts(1_655_000_000, 0)
 			.saturating_add(Weight::from_parts(0, 7404))
 			.saturating_add(T::DbWeight::get().reads(8))
 			.saturating_add(T::DbWeight::get().writes(7))
 	}
 	/// Storage: `AssetConversion::Pools` (r:1 w:0)
 	/// Proof: `AssetConversion::Pools` (`max_values`: None, `max_size`: Some(1224), added: 3699, mode: `MaxEncodedLen`)
-	/// Storage: `System::Account` (r:1 w:1)
-	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Asset` (r:1 w:1)
 	/// Proof: `ForeignAssets::Asset` (`max_values`: None, `max_size`: Some(808), added: 3283, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Account` (r:2 w:2)
 	/// Proof: `ForeignAssets::Account` (`max_values`: None, `max_size`: Some(732), added: 3207, mode: `MaxEncodedLen`)
+	/// Storage: `System::Account` (r:1 w:1)
+	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
 	/// Storage: `PoolAssets::Asset` (r:1 w:1)
 	/// Proof: `PoolAssets::Asset` (`max_values`: None, `max_size`: Some(210), added: 2685, mode: `MaxEncodedLen`)
-	/// Storage: UNKNOWN KEY `0x2433d831722b1f4aeb1666953f1c0e77` (r:1 w:0)
-	/// Proof: UNKNOWN KEY `0x2433d831722b1f4aeb1666953f1c0e77` (r:1 w:0)
 	/// Storage: `PoolAssets::Account` (r:1 w:1)
 	/// Proof: `PoolAssets::Account` (`max_values`: None, `max_size`: Some(134), added: 2609, mode: `MaxEncodedLen`)
 	fn remove_liquidity() -> Weight {
 		// Proof Size summary in bytes:
 		//  Measured:  `1106`
 		//  Estimated: `7404`
-		// Minimum execution time: 141_326_000 picoseconds.
-		Weight::from_parts(143_882_000, 0)
+		// Minimum execution time: 1_500_000_000 picoseconds.
+		Weight::from_parts(1_633_000_000, 0)
 			.saturating_add(Weight::from_parts(0, 7404))
-			.saturating_add(T::DbWeight::get().reads(8))
+			.saturating_add(T::DbWeight::get().reads(7))
 			.saturating_add(T::DbWeight::get().writes(6))
 	}
 	/// Storage: `ForeignAssets::Asset` (r:2 w:2)
@@ -127,15 +119,19 @@ impl<T: frame_system::Config> pallet_asset_conversion::WeightInfo for WeightInfo
 	/// Proof: `ForeignAssets::Account` (`max_values`: None, `max_size`: Some(732), added: 3207, mode: `MaxEncodedLen`)
 	/// Storage: `System::Account` (r:2 w:2)
 	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
-	fn swap_exact_tokens_for_tokens() -> Weight {
+	/// The range of component `n` is `[2, 3]`.
+	fn swap_exact_tokens_for_tokens(n: u32, ) -> Weight {
 		// Proof Size summary in bytes:
-		//  Measured:  `1148`
-		//  Estimated: `13818`
-		// Minimum execution time: 168_556_000 picoseconds.
-		Weight::from_parts(170_313_000, 0)
-			.saturating_add(Weight::from_parts(0, 13818))
-			.saturating_add(T::DbWeight::get().reads(8))
-			.saturating_add(T::DbWeight::get().writes(8))
+		//  Measured:  `0 + n * (557 ±0)`
+		//  Estimated: `7404 + n * (393 ±92)`
+		// Minimum execution time: 930_000_000 picoseconds.
+		Weight::from_parts(960_000_000, 0)
+			.saturating_add(Weight::from_parts(0, 7404))
+			// Standard Error: 17_993_720
+			.saturating_add(Weight::from_parts(41_959_183, 0).saturating_mul(n.into()))
+			.saturating_add(T::DbWeight::get().reads(4))
+			.saturating_add(T::DbWeight::get().writes(4))
+			.saturating_add(Weight::from_parts(0, 393).saturating_mul(n.into()))
 	}
 	/// Storage: `System::Account` (r:2 w:2)
 	/// Proof: `System::Account` (`max_values`: None, `max_size`: Some(128), added: 2603, mode: `MaxEncodedLen`)
@@ -143,14 +139,18 @@ impl<T: frame_system::Config> pallet_asset_conversion::WeightInfo for WeightInfo
 	/// Proof: `ForeignAssets::Asset` (`max_values`: None, `max_size`: Some(808), added: 3283, mode: `MaxEncodedLen`)
 	/// Storage: `ForeignAssets::Account` (r:4 w:4)
 	/// Proof: `ForeignAssets::Account` (`max_values`: None, `max_size`: Some(732), added: 3207, mode: `MaxEncodedLen`)
-	fn swap_tokens_for_exact_tokens() -> Weight {
+	/// The range of component `n` is `[2, 3]`.
+	fn swap_tokens_for_exact_tokens(n: u32, ) -> Weight {
 		// Proof Size summary in bytes:
-		//  Measured:  `1148`
-		//  Estimated: `13818`
-		// Minimum execution time: 167_704_000 picoseconds.
-		Weight::from_parts(170_034_000, 0)
-			.saturating_add(Weight::from_parts(0, 13818))
-			.saturating_add(T::DbWeight::get().reads(8))
-			.saturating_add(T::DbWeight::get().writes(8))
+		//  Measured:  `0 + n * (557 ±0)`
+		//  Estimated: `7404 + n * (393 ±92)`
+		// Minimum execution time: 940_000_000 picoseconds.
+		Weight::from_parts(956_000_000, 0)
+			.saturating_add(Weight::from_parts(0, 7404))
+			// Standard Error: 15_746_647
+			.saturating_add(Weight::from_parts(39_193_877, 0).saturating_mul(n.into()))
+			.saturating_add(T::DbWeight::get().reads(4))
+			.saturating_add(T::DbWeight::get().writes(4))
+			.saturating_add(Weight::from_parts(0, 393).saturating_mul(n.into()))
 	}
 }

cumulus/parachains/runtimes/assets/asset-hub-westend/src/xcm_config.rs

@@ -56,9 +56,6 @@ use xcm_builder::{
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};
 
-#[cfg(feature = "runtime-benchmarks")]
-use {cumulus_primitives_core::ParaId, sp_core::Get};
-
 parameter_types! {
 	pub const WestendLocation: MultiLocation = MultiLocation::parent();
 	pub const RelayNetwork: Option<NetworkId> = Some(NetworkId::Westend);
@@ -66,8 +63,8 @@ parameter_types! {
 	pub UniversalLocation: InteriorMultiLocation =
 		X2(GlobalConsensus(RelayNetwork::get().unwrap()), Parachain(ParachainInfo::parachain_id().into()));
 	pub UniversalLocationNetworkId: NetworkId = UniversalLocation::get().global_consensus().unwrap();
-	pub TrustBackedAssetsPalletLocation: MultiLocation =
-		PalletInstance(<Assets as PalletInfoAccess>::index() as u8).into();
+	pub AssetsPalletIndex: u32 = <Assets as PalletInfoAccess>::index() as u32;
+	pub TrustBackedAssetsPalletLocation: MultiLocation = PalletInstance(AssetsPalletIndex::get() as u8).into();
 	pub ForeignAssetsPalletLocation: MultiLocation =
 		PalletInstance(<ForeignAssets as PalletInfoAccess>::index() as u8).into();
 	pub PoolAssetsPalletLocation: MultiLocation =
@@ -694,33 +691,6 @@ impl pallet_assets::BenchmarkHelper<MultiLocation> for XcmBenchmarkHelper {
 	}
 }
 
-#[cfg(feature = "runtime-benchmarks")]
-pub struct BenchmarkMultiLocationConverter<SelfParaId> {
-	_phantom: sp_std::marker::PhantomData<SelfParaId>,
-}
-
-#[cfg(feature = "runtime-benchmarks")]
-impl<SelfParaId> pallet_asset_conversion::BenchmarkHelper<MultiLocation, MultiLocation>
-	for BenchmarkMultiLocationConverter<SelfParaId>
-where
-	SelfParaId: Get<ParaId>,
-{
-	fn asset_id(asset_id: u32) -> MultiLocation {
-		MultiLocation {
-			parents: 1,
-			interior: X3(
-				Parachain(SelfParaId::get().into()),
-				PalletInstance(<Assets as PalletInfoAccess>::index() as u8),
-				GeneralIndex(asset_id.into()),
-			),
-		}
-	}
-
-	fn multiasset_id(asset_id: u32) -> MultiLocation {
-		Self::asset_id(asset_id)
-	}
-}
-
 /// All configuration related to bridging
 pub mod bridging {
 	use super::*;