XCMv4 (#1230)

# Note for reviewer

Most changes are just syntax changes necessary for the new version.
Most important files should be the ones under the `xcm` folder.

# Description 

Added XCMv4.

## Removed `Multi` prefix
The following types have been renamed:
- MultiLocation -> Location
- MultiAsset -> Asset
- MultiAssets -> Assets
- InteriorMultiLocation -> InteriorLocation
- MultiAssetFilter -> AssetFilter
- VersionedMultiAsset -> VersionedAsset
- WildMultiAsset -> WildAsset
- VersionedMultiLocation -> VersionedLocation

In order to fix a name conflict, the `Assets` in `xcm-executor` were
renamed to `HoldingAssets`, as they represent assets in holding.

## Removed `Abstract` asset id

It was not being used anywhere and this simplifies the code.

Now assets are just constructed as follows:

```rust
let asset: Asset = (AssetId(Location::new(1, Here)), 100u128).into();
```

No need for specifying `Concrete` anymore.

## Outcome is now a named fields struct

Instead of

```rust
pub enum Outcome {
  Complete(Weight),
  Incomplete(Weight, Error),
  Error(Error),
}
```

we now have

```rust
pub enum Outcome {
  Complete { used: Weight },
  Incomplete { used: Weight, error: Error },
  Error { error: Error },
}
```

## Added Reanchorable trait

Now both locations and assets implement this trait, making it easier to
reanchor both.

## New syntax for building locations and junctions

Now junctions are built using the following methods:

```rust
let location = Location {
    parents: 1,
    interior: [Parachain(1000), PalletInstance(50), GeneralIndex(1984)].into()
};
```

or

```rust
let location = Location::new(1, [Parachain(1000), PalletInstance(50), GeneralIndex(1984)]);
```

And they are matched like so:

```rust
match location.unpack() {
  (1, [Parachain(id)]) => ...
  (0, Here) => ...,
  (1, [_]) => ...,
}
```

This syntax is mandatory in v4, and has been also implemented for v2 and
v3 for easier migration.

This was needed to make all sizes smaller.

# TODO
- [x] Scaffold v4
- [x] Port github.com/paritytech/polkadot/pull/7236
- [x] Remove `Multi` prefix
- [x] Remove `Abstract` asset id

---------

Co-authored-by: command-bot <>
Co-authored-by: Keith Yeung <kungfukeith11@gmail.com>

polkadot/runtime/rococo/src/impls.rs

@@ -22,7 +22,7 @@ use primitives::Balance;
 use rococo_runtime_constants::currency::*;
 use runtime_common::identity_migrator::{OnReapIdentity, WeightInfo};
 use sp_std::{marker::PhantomData, prelude::*};
-use xcm::{latest::prelude::*, VersionedMultiLocation, VersionedXcm};
+use xcm::{latest::prelude::*, VersionedLocation, VersionedXcm};
 use xcm_executor::traits::TransactAsset;
 
 /// A type containing the encoding of the People Chain pallets in its runtime. Used to construct any
@@ -95,9 +95,9 @@ where
 		let total_to_send = Self::calculate_remote_deposit(fields, subs);
 
 		// define asset / destination from relay perspective
-		let roc = MultiAsset { id: Concrete(Here.into_location()), fun: Fungible(total_to_send) };
+		let roc = Asset { id: AssetId(Here.into_location()), fun: Fungible(total_to_send) };
 		// People Chain: ParaId 1004
-		let destination: MultiLocation = MultiLocation::new(0, Parachain(1004));
+		let destination: Location = Location::new(0, Parachain(1004));
 
 		// Do `check_out` accounting since the XCM Executor's `InitiateTeleport` doesn't support
 		// unpaid teleports.
@@ -138,11 +138,9 @@ where
 		);
 
 		// reanchor
-		let roc_reanchored: MultiAssets = vec![MultiAsset {
-			id: Concrete(MultiLocation::new(1, Here)),
-			fun: Fungible(total_to_send),
-		}]
-		.into();
+		let roc_reanchored: Assets =
+			vec![Asset { id: AssetId(Location::new(1, Here)), fun: Fungible(total_to_send) }]
+				.into();
 
 		let poke = PeopleRuntimePallets::<AccountId>::IdentityMigrator(PokeDeposit(who.clone()));
 		let remote_weight_limit = MigratorWeights::<Runtime>::poke_deposit().saturating_mul(2);
@@ -172,8 +170,8 @@ where
 		// send
 		let _ = <pallet_xcm::Pallet<Runtime>>::send(
 			RawOrigin::Root.into(),
-			Box::new(VersionedMultiLocation::V3(destination)),
-			Box::new(VersionedXcm::V3(program)),
+			Box::new(VersionedLocation::V4(destination)),
+			Box::new(VersionedXcm::V4(program)),
 		)?;
 		Ok(())
 	}

polkadot/runtime/rococo/src/lib.rs

@@ -35,7 +35,7 @@ use rococo_runtime_constants::system_parachain::BROKER_ID;
 use runtime_common::{
 	assigned_slots, auctions, claims, crowdloan, identity_migrator, impl_runtime_weights,
 	impls::{
-		LocatableAssetConverter, ToAuthor, VersionedLocatableAsset, VersionedMultiLocationConverter,
+		LocatableAssetConverter, ToAuthor, VersionedLocatableAsset, VersionedLocationConverter,
 	},
 	paras_registrar, paras_sudo_wrapper, prod_or_fast, slots,
 	traits::Leaser,
@@ -99,10 +99,7 @@ use sp_staking::SessionIndex;
 #[cfg(any(feature = "std", test))]
 use sp_version::NativeVersion;
 use sp_version::RuntimeVersion;
-use xcm::{
-	latest::{InteriorMultiLocation, Junction, Junction::PalletInstance},
-	VersionedMultiLocation,
-};
+use xcm::{latest::prelude::*, VersionedLocation};
 use xcm_builder::PayOverXcm;
 
 pub use frame_system::Call as SystemCall;
@@ -461,7 +458,7 @@ parameter_types! {
 	pub const PayoutSpendPeriod: BlockNumber = 30 * DAYS;
 	// The asset's interior location for the paying account. This is the Treasury
 	// pallet instance (which sits at index 18).
-	pub TreasuryInteriorLocation: InteriorMultiLocation = PalletInstance(18).into();
+	pub TreasuryInteriorLocation: InteriorLocation = PalletInstance(18).into();
 
 	pub const TipCountdown: BlockNumber = 1 * DAYS;
 	pub const TipFindersFee: Percent = Percent::from_percent(20);
@@ -492,7 +489,7 @@ impl pallet_treasury::Config for Runtime {
 	type SpendFunds = Bounties;
 	type SpendOrigin = TreasurySpender;
 	type AssetKind = VersionedLocatableAsset;
-	type Beneficiary = VersionedMultiLocation;
+	type Beneficiary = VersionedLocation;
 	type BeneficiaryLookup = IdentityLookup<Self::Beneficiary>;
 	type Paymaster = PayOverXcm<
 		TreasuryInteriorLocation,
@@ -502,7 +499,7 @@ impl pallet_treasury::Config for Runtime {
 		Self::Beneficiary,
 		Self::AssetKind,
 		LocatableAssetConverter,
-		VersionedMultiLocationConverter,
+		VersionedLocationConverter,
 	>;
 	type BalanceConverter = AssetRate;
 	type PayoutPeriod = PayoutSpendPeriod;
@@ -538,7 +535,7 @@ impl pallet_bounties::Config for Runtime {
 
 parameter_types! {
 	pub const MaxActiveChildBountyCount: u32 = 100;
-	pub const ChildBountyValueMinimum: Balance = BountyValueMinimum::get() / 10;
+	pub ChildBountyValueMinimum: Balance = BountyValueMinimum::get() / 10;
 }
 
 impl pallet_child_bounties::Config for Runtime {
@@ -1209,7 +1206,7 @@ impl pallet_nis::Config for Runtime {
 }
 
 parameter_types! {
-	pub const BeefySetIdSessionEntries: u32 = BondingDuration::get() * SessionsPerEra::get();
+	pub BeefySetIdSessionEntries: u32 = BondingDuration::get() * SessionsPerEra::get();
 }
 
 impl pallet_beefy::Config for Runtime {
@@ -2270,7 +2267,7 @@ sp_api::impl_runtime_apis! {
 			};
 
 			parameter_types! {
-				pub ExistentialDepositMultiAsset: Option<MultiAsset> = Some((
+				pub ExistentialDepositAsset: Option<Asset> = Some((
 					TokenLocation::get(),
 					ExistentialDeposit::get()
 				).into());
@@ -2280,34 +2277,34 @@ sp_api::impl_runtime_apis! {
 			impl frame_system_benchmarking::Config for Runtime {}
 			impl frame_benchmarking::baseline::Config for Runtime {}
 			impl pallet_xcm::benchmarking::Config for Runtime {
-				fn reachable_dest() -> Option<MultiLocation> {
+				fn reachable_dest() -> Option<Location> {
 					Some(crate::xcm_config::AssetHub::get())
 				}
 
-				fn teleportable_asset_and_dest() -> Option<(MultiAsset, MultiLocation)> {
+				fn teleportable_asset_and_dest() -> Option<(Asset, Location)> {
 					// Relay/native token can be teleported to/from AH.
 					Some((
-						MultiAsset {
+						Asset {
 							fun: Fungible(EXISTENTIAL_DEPOSIT),
-							id: Concrete(Here.into())
+							id: AssetId(Here.into())
 						},
 						crate::xcm_config::AssetHub::get(),
 					))
 				}
 
-				fn reserve_transferable_asset_and_dest() -> Option<(MultiAsset, MultiLocation)> {
+				fn reserve_transferable_asset_and_dest() -> Option<(Asset, Location)> {
 					// Relay can reserve transfer native token to some random parachain.
 					Some((
-						MultiAsset {
+						Asset {
 							fun: Fungible(EXISTENTIAL_DEPOSIT),
-							id: Concrete(Here.into())
+							id: AssetId(Here.into())
 						},
 						Parachain(43211234).into(),
 					))
 				}
 
 				fn set_up_complex_asset_transfer(
-				) -> Option<(MultiAssets, u32, MultiLocation, Box<dyn FnOnce()>)> {
+				) -> Option<(Assets, u32, Location, Box<dyn FnOnce()>)> {
 					// Relay supports only native token, either reserve transfer it to non-system parachains,
 					// or teleport it to system parachain. Use the teleport case for benchmarking as it's
 					// slightly heavier.
@@ -2325,29 +2322,29 @@ sp_api::impl_runtime_apis! {
 				type AccountIdConverter = LocationConverter;
 				type DeliveryHelper = runtime_common::xcm_sender::ToParachainDeliveryHelper<
 					XcmConfig,
-					ExistentialDepositMultiAsset,
+					ExistentialDepositAsset,
 					xcm_config::PriceForChildParachainDelivery,
 					ToParachain,
 					(),
 				>;
-				fn valid_destination() -> Result<MultiLocation, BenchmarkError> {
+				fn valid_destination() -> Result<Location, BenchmarkError> {
 					Ok(AssetHub::get())
 				}
-				fn worst_case_holding(_depositable_count: u32) -> MultiAssets {
+				fn worst_case_holding(_depositable_count: u32) -> Assets {
 					// Rococo only knows about ROC
-					vec![MultiAsset{
-						id: Concrete(TokenLocation::get()),
+					vec![Asset{
+						id: AssetId(TokenLocation::get()),
 						fun: Fungible(1_000_000 * UNITS),
 					}].into()
 				}
 			}
 
 			parameter_types! {
-				pub const TrustedTeleporter: Option<(MultiLocation, MultiAsset)> = Some((
+				pub TrustedTeleporter: Option<(Location, Asset)> = Some((
 					AssetHub::get(),
-					MultiAsset { fun: Fungible(1 * UNITS), id: Concrete(TokenLocation::get()) },
+					Asset { fun: Fungible(1 * UNITS), id: AssetId(TokenLocation::get()) },
 				));
-				pub const TrustedReserve: Option<(MultiLocation, MultiAsset)> = None;
+				pub TrustedReserve: Option<(Location, Asset)> = None;
 			}
 
 			impl pallet_xcm_benchmarks::fungible::Config for Runtime {
@@ -2357,9 +2354,9 @@ sp_api::impl_runtime_apis! {
 				type TrustedTeleporter = TrustedTeleporter;
 				type TrustedReserve = TrustedReserve;
 
-				fn get_multi_asset() -> MultiAsset {
-					MultiAsset {
-						id: Concrete(TokenLocation::get()),
+				fn get_asset() -> Asset {
+					Asset {
+						id: AssetId(TokenLocation::get()),
 						fun: Fungible(1 * UNITS),
 					}
 				}
@@ -2373,43 +2370,43 @@ sp_api::impl_runtime_apis! {
 					(0u64, Response::Version(Default::default()))
 				}
 
-				fn worst_case_asset_exchange() -> Result<(MultiAssets, MultiAssets), BenchmarkError> {
+				fn worst_case_asset_exchange() -> Result<(Assets, Assets), BenchmarkError> {
 					// Rococo doesn't support asset exchanges
 					Err(BenchmarkError::Skip)
 				}
 
-				fn universal_alias() -> Result<(MultiLocation, Junction), BenchmarkError> {
+				fn universal_alias() -> Result<(Location, Junction), BenchmarkError> {
 					// The XCM executor of Rococo doesn't have a configured `UniversalAliases`
 					Err(BenchmarkError::Skip)
 				}
 
-				fn transact_origin_and_runtime_call() -> Result<(MultiLocation, RuntimeCall), BenchmarkError> {
+				fn transact_origin_and_runtime_call() -> Result<(Location, RuntimeCall), BenchmarkError> {
 					Ok((AssetHub::get(), frame_system::Call::remark_with_event { remark: vec![] }.into()))
 				}
 
-				fn subscribe_origin() -> Result<MultiLocation, BenchmarkError> {
+				fn subscribe_origin() -> Result<Location, BenchmarkError> {
 					Ok(AssetHub::get())
 				}
 
-				fn claimable_asset() -> Result<(MultiLocation, MultiLocation, MultiAssets), BenchmarkError> {
+				fn claimable_asset() -> Result<(Location, Location, Assets), BenchmarkError> {
 					let origin = AssetHub::get();
-					let assets: MultiAssets = (Concrete(TokenLocation::get()), 1_000 * UNITS).into();
-					let ticket = MultiLocation { parents: 0, interior: Here };
+					let assets: Assets = (AssetId(TokenLocation::get()), 1_000 * UNITS).into();
+					let ticket = Location { parents: 0, interior: Here };
 					Ok((origin, ticket, assets))
 				}
 
-				fn unlockable_asset() -> Result<(MultiLocation, MultiLocation, MultiAsset), BenchmarkError> {
+				fn unlockable_asset() -> Result<(Location, Location, Asset), BenchmarkError> {
 					// Rococo doesn't support asset locking
 					Err(BenchmarkError::Skip)
 				}
 
 				fn export_message_origin_and_destination(
-				) -> Result<(MultiLocation, NetworkId, InteriorMultiLocation), BenchmarkError> {
+				) -> Result<(Location, NetworkId, InteriorLocation), BenchmarkError> {
 					// Rococo doesn't support exporting messages
 					Err(BenchmarkError::Skip)
 				}
 
-				fn alias_origin() -> Result<(MultiLocation, MultiLocation), BenchmarkError> {
+				fn alias_origin() -> Result<(Location, Location), BenchmarkError> {
 					// The XCM executor of Rococo doesn't have a configured `Aliasers`
 					Err(BenchmarkError::Skip)
 				}

polkadot/runtime/rococo/src/weights/xcm/mod.rs

@@ -33,25 +33,25 @@ pub enum AssetTypes {
 	Unknown,
 }
 
-impl From<&MultiAsset> for AssetTypes {
-	fn from(asset: &MultiAsset) -> Self {
+impl From<&Asset> for AssetTypes {
+	fn from(asset: &Asset) -> Self {
 		match asset {
-			MultiAsset { id: Concrete(MultiLocation { parents: 0, interior: Here }), .. } =>
+			Asset { id: AssetId(Location { parents: 0, interior: Here }), .. } =>
 				AssetTypes::Balances,
 			_ => AssetTypes::Unknown,
 		}
 	}
 }
 
-trait WeighMultiAssets {
-	fn weigh_multi_assets(&self, balances_weight: Weight) -> Weight;
+trait WeighAssets {
+	fn weigh_assets(&self, balances_weight: Weight) -> Weight;
 }
 
 // Rococo only knows about one asset, the balances pallet.
 const MAX_ASSETS: u64 = 1;
 
-impl WeighMultiAssets for MultiAssetFilter {
-	fn weigh_multi_assets(&self, balances_weight: Weight) -> Weight {
+impl WeighAssets for AssetFilter {
+	fn weigh_assets(&self, balances_weight: Weight) -> Weight {
 		match self {
 			Self::Definite(assets) => assets
 				.inner()
@@ -72,11 +72,11 @@ impl WeighMultiAssets for MultiAssetFilter {
 	}
 }
 
-impl WeighMultiAssets for MultiAssets {
-	fn weigh_multi_assets(&self, balances_weight: Weight) -> Weight {
+impl WeighAssets for Assets {
+	fn weigh_assets(&self, balances_weight: Weight) -> Weight {
 		self.inner()
 			.into_iter()
-			.map(|m| <AssetTypes as From<&MultiAsset>>::from(m))
+			.map(|m| <AssetTypes as From<&Asset>>::from(m))
 			.map(|t| match t {
 				AssetTypes::Balances => balances_weight,
 				AssetTypes::Unknown => Weight::MAX,
@@ -87,32 +87,28 @@ impl WeighMultiAssets for MultiAssets {
 
 pub struct RococoXcmWeight<RuntimeCall>(core::marker::PhantomData<RuntimeCall>);
 impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
-	fn withdraw_asset(assets: &MultiAssets) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::withdraw_asset())
+	fn withdraw_asset(assets: &Assets) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::withdraw_asset())
 	}
-	fn reserve_asset_deposited(assets: &MultiAssets) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::reserve_asset_deposited())
+	fn reserve_asset_deposited(assets: &Assets) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::reserve_asset_deposited())
 	}
-	fn receive_teleported_asset(assets: &MultiAssets) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::receive_teleported_asset())
+	fn receive_teleported_asset(assets: &Assets) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::receive_teleported_asset())
 	}
 	fn query_response(
 		_query_id: &u64,
 		_response: &Response,
 		_max_weight: &Weight,
-		_querier: &Option<MultiLocation>,
+		_querier: &Option<Location>,
 	) -> Weight {
 		XcmGeneric::<Runtime>::query_response()
 	}
-	fn transfer_asset(assets: &MultiAssets, _dest: &MultiLocation) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::transfer_asset())
+	fn transfer_asset(assets: &Assets, _dest: &Location) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::transfer_asset())
 	}
-	fn transfer_reserve_asset(
-		assets: &MultiAssets,
-		_dest: &MultiLocation,
-		_xcm: &Xcm<()>,
-	) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::transfer_reserve_asset())
+	fn transfer_reserve_asset(assets: &Assets, _dest: &Location, _xcm: &Xcm<()>) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::transfer_reserve_asset())
 	}
 	fn transact(
 		_origin_kind: &OriginKind,
@@ -140,45 +136,37 @@ impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
 	fn clear_origin() -> Weight {
 		XcmGeneric::<Runtime>::clear_origin()
 	}
-	fn descend_origin(_who: &InteriorMultiLocation) -> Weight {
+	fn descend_origin(_who: &InteriorLocation) -> Weight {
 		XcmGeneric::<Runtime>::descend_origin()
 	}
 	fn report_error(_query_response_info: &QueryResponseInfo) -> Weight {
 		XcmGeneric::<Runtime>::report_error()
 	}
 
-	fn deposit_asset(assets: &MultiAssetFilter, _dest: &MultiLocation) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::deposit_asset())
+	fn deposit_asset(assets: &AssetFilter, _dest: &Location) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::deposit_asset())
 	}
-	fn deposit_reserve_asset(
-		assets: &MultiAssetFilter,
-		_dest: &MultiLocation,
-		_xcm: &Xcm<()>,
-	) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::deposit_reserve_asset())
+	fn deposit_reserve_asset(assets: &AssetFilter, _dest: &Location, _xcm: &Xcm<()>) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::deposit_reserve_asset())
 	}
-	fn exchange_asset(_give: &MultiAssetFilter, _receive: &MultiAssets, _maximal: &bool) -> Weight {
+	fn exchange_asset(_give: &AssetFilter, _receive: &Assets, _maximal: &bool) -> Weight {
 		// Rococo does not currently support exchange asset operations
 		Weight::MAX
 	}
 	fn initiate_reserve_withdraw(
-		assets: &MultiAssetFilter,
-		_reserve: &MultiLocation,
+		assets: &AssetFilter,
+		_reserve: &Location,
 		_xcm: &Xcm<()>,
 	) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::initiate_reserve_withdraw())
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::initiate_reserve_withdraw())
 	}
-	fn initiate_teleport(
-		assets: &MultiAssetFilter,
-		_dest: &MultiLocation,
-		_xcm: &Xcm<()>,
-	) -> Weight {
-		assets.weigh_multi_assets(XcmBalancesWeight::<Runtime>::initiate_teleport())
+	fn initiate_teleport(assets: &AssetFilter, _dest: &Location, _xcm: &Xcm<()>) -> Weight {
+		assets.weigh_assets(XcmBalancesWeight::<Runtime>::initiate_teleport())
 	}
-	fn report_holding(_response_info: &QueryResponseInfo, _assets: &MultiAssetFilter) -> Weight {
+	fn report_holding(_response_info: &QueryResponseInfo, _assets: &AssetFilter) -> Weight {
 		XcmGeneric::<Runtime>::report_holding()
 	}
-	fn buy_execution(_fees: &MultiAsset, _weight_limit: &WeightLimit) -> Weight {
+	fn buy_execution(_fees: &Asset, _weight_limit: &WeightLimit) -> Weight {
 		XcmGeneric::<Runtime>::buy_execution()
 	}
 	fn refund_surplus() -> Weight {
@@ -193,7 +181,7 @@ impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
 	fn clear_error() -> Weight {
 		XcmGeneric::<Runtime>::clear_error()
 	}
-	fn claim_asset(_assets: &MultiAssets, _ticket: &MultiLocation) -> Weight {
+	fn claim_asset(_assets: &Assets, _ticket: &Location) -> Weight {
 		XcmGeneric::<Runtime>::claim_asset()
 	}
 	fn trap(_code: &u64) -> Weight {
@@ -205,13 +193,13 @@ impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
 	fn unsubscribe_version() -> Weight {
 		XcmGeneric::<Runtime>::unsubscribe_version()
 	}
-	fn burn_asset(assets: &MultiAssets) -> Weight {
-		assets.weigh_multi_assets(XcmGeneric::<Runtime>::burn_asset())
+	fn burn_asset(assets: &Assets) -> Weight {
+		assets.weigh_assets(XcmGeneric::<Runtime>::burn_asset())
 	}
-	fn expect_asset(assets: &MultiAssets) -> Weight {
-		assets.weigh_multi_assets(XcmGeneric::<Runtime>::expect_asset())
+	fn expect_asset(assets: &Assets) -> Weight {
+		assets.weigh_assets(XcmGeneric::<Runtime>::expect_asset())
 	}
-	fn expect_origin(_origin: &Option<MultiLocation>) -> Weight {
+	fn expect_origin(_origin: &Option<Location>) -> Weight {
 		XcmGeneric::<Runtime>::expect_origin()
 	}
 	fn expect_error(_error: &Option<(u32, XcmError)>) -> Weight {
@@ -246,19 +234,19 @@ impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
 		// Rococo relay should not support export message operations
 		Weight::MAX
 	}
-	fn lock_asset(_: &MultiAsset, _: &MultiLocation) -> Weight {
+	fn lock_asset(_: &Asset, _: &Location) -> Weight {
 		// Rococo does not currently support asset locking operations
 		Weight::MAX
 	}
-	fn unlock_asset(_: &MultiAsset, _: &MultiLocation) -> Weight {
+	fn unlock_asset(_: &Asset, _: &Location) -> Weight {
 		// Rococo does not currently support asset locking operations
 		Weight::MAX
 	}
-	fn note_unlockable(_: &MultiAsset, _: &MultiLocation) -> Weight {
+	fn note_unlockable(_: &Asset, _: &Location) -> Weight {
 		// Rococo does not currently support asset locking operations
 		Weight::MAX
 	}
-	fn request_unlock(_: &MultiAsset, _: &MultiLocation) -> Weight {
+	fn request_unlock(_: &Asset, _: &Location) -> Weight {
 		// Rococo does not currently support asset locking operations
 		Weight::MAX
 	}
@@ -271,19 +259,19 @@ impl<RuntimeCall> XcmWeightInfo<RuntimeCall> for RococoXcmWeight<RuntimeCall> {
 	fn clear_topic() -> Weight {
 		XcmGeneric::<Runtime>::clear_topic()
 	}
-	fn alias_origin(_: &MultiLocation) -> Weight {
+	fn alias_origin(_: &Location) -> Weight {
 		// XCM Executor does not currently support alias origin operations
 		Weight::MAX
 	}
-	fn unpaid_execution(_: &WeightLimit, _: &Option<MultiLocation>) -> Weight {
+	fn unpaid_execution(_: &WeightLimit, _: &Option<Location>) -> Weight {
 		XcmGeneric::<Runtime>::unpaid_execution()
 	}
 }
 
 #[test]
 fn all_counted_has_a_sane_weight_upper_limit() {
-	let assets = MultiAssetFilter::Wild(AllCounted(4294967295));
+	let assets = AssetFilter::Wild(AllCounted(4294967295));
 	let weight = Weight::from_parts(1000, 1000);
 
-	assert_eq!(assets.weigh_multi_assets(weight), weight * MAX_ASSETS);
+	assert_eq!(assets.weigh_assets(weight), weight * MAX_ASSETS);
 }

polkadot/runtime/rococo/src/xcm_config.rs

@@ -24,8 +24,8 @@ use super::{
 use crate::governance::StakingAdmin;
 
 use frame_support::{
-	match_types, parameter_types,
-	traits::{Equals, Everything, Nothing},
+	parameter_types,
+	traits::{Contains, Equals, Everything, Nothing},
 	weights::Weight,
 };
 use frame_system::EnsureRoot;
@@ -50,10 +50,10 @@ use xcm_builder::{
 use xcm_executor::XcmExecutor;
 
 parameter_types! {
-	pub const RootLocation: MultiLocation = MultiLocation::here();
-	pub const TokenLocation: MultiLocation = Here.into_location();
+	pub TokenLocation: Location = Here.into_location();
+	pub RootLocation: Location = Location::here();
 	pub const ThisNetwork: NetworkId = NetworkId::Rococo;
-	pub UniversalLocation: InteriorMultiLocation = ThisNetwork::get().into();
+	pub UniversalLocation: InteriorLocation = ThisNetwork::get().into();
 	pub CheckAccount: AccountId = XcmPallet::check_account();
 	pub LocalCheckAccount: (AccountId, MintLocation) = (CheckAccount::get(), MintLocation::Local);
 	pub TreasuryAccount: AccountId = Treasury::account_id();
@@ -69,7 +69,7 @@ pub type LocationConverter = (
 );
 
 /// Our asset transactor. This is what allows us to interest with the runtime facilities from the
-/// point of view of XCM-only concepts like `MultiLocation` and `MultiAsset`.
+/// point of view of XCM-only concepts like `Location` and `Asset`.
 ///
 /// Ours is only aware of the Balances pallet, which is mapped to `RocLocation`.
 #[allow(deprecated)]
@@ -78,7 +78,7 @@ pub type LocalAssetTransactor = XcmCurrencyAdapter<
 	Balances,
 	// Use this currency when it is a fungible asset matching the given location or name:
 	IsConcrete<TokenLocation>,
-	// We can convert the MultiLocations with our converter above:
+	// We can convert the Locations with our converter above:
 	LocationConverter,
 	// Our chain's account ID type (we can't get away without mentioning it explicitly):
 	AccountId,
@@ -100,7 +100,7 @@ parameter_types! {
 	/// The amount of weight an XCM operation takes. This is a safe overestimate.
 	pub const BaseXcmWeight: Weight = Weight::from_parts(1_000_000_000, 64 * 1024);
 	/// The asset ID for the asset that we use to pay for message delivery fees.
-	pub FeeAssetId: AssetId = Concrete(TokenLocation::get());
+	pub FeeAssetId: AssetId = AssetId(TokenLocation::get());
 	/// The base fee for the message delivery fees.
 	pub const BaseDeliveryFee: u128 = CENTS.saturating_mul(3);
 }
@@ -116,25 +116,25 @@ pub type XcmRouter = WithUniqueTopic<
 >;
 
 parameter_types! {
-	pub const Roc: MultiAssetFilter = Wild(AllOf { fun: WildFungible, id: Concrete(TokenLocation::get()) });
-	pub const AssetHub: MultiLocation = Parachain(ASSET_HUB_ID).into_location();
-	pub const Contracts: MultiLocation = Parachain(CONTRACTS_ID).into_location();
-	pub const Encointer: MultiLocation = Parachain(ENCOINTER_ID).into_location();
-	pub const BridgeHub: MultiLocation = Parachain(BRIDGE_HUB_ID).into_location();
-	pub const People: MultiLocation = Parachain(PEOPLE_ID).into_location();
-	pub const Broker: MultiLocation = Parachain(BROKER_ID).into_location();
-	pub const Tick: MultiLocation = Parachain(100).into_location();
-	pub const Trick: MultiLocation = Parachain(110).into_location();
-	pub const Track: MultiLocation = Parachain(120).into_location();
-	pub const RocForTick: (MultiAssetFilter, MultiLocation) = (Roc::get(), Tick::get());
-	pub const RocForTrick: (MultiAssetFilter, MultiLocation) = (Roc::get(), Trick::get());
-	pub const RocForTrack: (MultiAssetFilter, MultiLocation) = (Roc::get(), Track::get());
-	pub const RocForAssetHub: (MultiAssetFilter, MultiLocation) = (Roc::get(), AssetHub::get());
-	pub const RocForContracts: (MultiAssetFilter, MultiLocation) = (Roc::get(), Contracts::get());
-	pub const RocForEncointer: (MultiAssetFilter, MultiLocation) = (Roc::get(), Encointer::get());
-	pub const RocForBridgeHub: (MultiAssetFilter, MultiLocation) = (Roc::get(), BridgeHub::get());
-	pub const RocForPeople: (MultiAssetFilter, MultiLocation) = (Roc::get(), People::get());
-	pub const RocForBroker: (MultiAssetFilter, MultiLocation) = (Roc::get(), Broker::get());
+	pub Roc: AssetFilter = Wild(AllOf { fun: WildFungible, id: AssetId(TokenLocation::get()) });
+	pub AssetHub: Location = Parachain(ASSET_HUB_ID).into_location();
+	pub Contracts: Location = Parachain(CONTRACTS_ID).into_location();
+	pub Encointer: Location = Parachain(ENCOINTER_ID).into_location();
+	pub BridgeHub: Location = Parachain(BRIDGE_HUB_ID).into_location();
+	pub People: Location = Parachain(PEOPLE_ID).into_location();
+	pub Broker: Location = Parachain(BROKER_ID).into_location();
+	pub Tick: Location = Parachain(100).into_location();
+	pub Trick: Location = Parachain(110).into_location();
+	pub Track: Location = Parachain(120).into_location();
+	pub RocForTick: (AssetFilter, Location) = (Roc::get(), Tick::get());
+	pub RocForTrick: (AssetFilter, Location) = (Roc::get(), Trick::get());
+	pub RocForTrack: (AssetFilter, Location) = (Roc::get(), Track::get());
+	pub RocForAssetHub: (AssetFilter, Location) = (Roc::get(), AssetHub::get());
+	pub RocForContracts: (AssetFilter, Location) = (Roc::get(), Contracts::get());
+	pub RocForEncointer: (AssetFilter, Location) = (Roc::get(), Encointer::get());
+	pub RocForBridgeHub: (AssetFilter, Location) = (Roc::get(), BridgeHub::get());
+	pub RocForPeople: (AssetFilter, Location) = (Roc::get(), People::get());
+	pub RocForBroker: (AssetFilter, Location) = (Roc::get(), Broker::get());
 	pub const MaxInstructions: u32 = 100;
 	pub const MaxAssetsIntoHolding: u32 = 64;
 }
@@ -150,13 +150,18 @@ pub type TrustedTeleporters = (
 	xcm_builder::Case<RocForBroker>,
 );
 
-match_types! {
-	pub type OnlyParachains: impl Contains<MultiLocation> = {
-		MultiLocation { parents: 0, interior: X1(Parachain(_)) }
-	};
-	pub type LocalPlurality: impl Contains<MultiLocation> = {
-		MultiLocation { parents: 0, interior: X1(Plurality { .. }) }
-	};
+pub struct OnlyParachains;
+impl Contains<Location> for OnlyParachains {
+	fn contains(loc: &Location) -> bool {
+		matches!(loc.unpack(), (0, [Parachain(_)]))
+	}
+}
+
+pub struct LocalPlurality;
+impl Contains<Location> for LocalPlurality {
+	fn contains(loc: &Location) -> bool {
+		matches!(loc.unpack(), (0, [Plurality { .. }]))
+	}
 }
 
 /// The barriers one of which must be passed for an XCM message to be executed.
@@ -227,26 +232,26 @@ parameter_types! {
 	pub const FellowsBodyId: BodyId = BodyId::Technical;
 }
 
-/// Type to convert an `Origin` type value into a `MultiLocation` value which represents an interior
+/// Type to convert an `Origin` type value into a `Location` value which represents an interior
 /// location of this chain.
 pub type LocalOriginToLocation = (
 	// And a usual Signed origin to be used in XCM as a corresponding AccountId32
 	SignedToAccountId32<RuntimeOrigin, AccountId, ThisNetwork>,
 );
 
-/// Type to convert the `StakingAdmin` origin to a Plurality `MultiLocation` value.
+/// Type to convert the `StakingAdmin` origin to a Plurality `Location` value.
 pub type StakingAdminToPlurality =
 	OriginToPluralityVoice<RuntimeOrigin, StakingAdmin, StakingAdminBodyId>;
 
-/// Type to convert the Fellows origin to a Plurality `MultiLocation` value.
+/// Type to convert the Fellows origin to a Plurality `Location` value.
 pub type FellowsToPlurality = OriginToPluralityVoice<RuntimeOrigin, Fellows, FellowsBodyId>;
 
-/// Type to convert a pallet `Origin` type value into a `MultiLocation` value which represents an
+/// Type to convert a pallet `Origin` type value into a `Location` value which represents an
 /// interior location of this chain for a destination chain.
 pub type LocalPalletOriginToLocation = (
-	// StakingAdmin origin to be used in XCM as a corresponding Plurality `MultiLocation` value.
+	// StakingAdmin origin to be used in XCM as a corresponding Plurality `Location` value.
 	StakingAdminToPlurality,
-	// Fellows origin to be used in XCM as a corresponding Plurality `MultiLocation` value.
+	// Fellows origin to be used in XCM as a corresponding Plurality `Location` value.
 	FellowsToPlurality,
 );