Ensure MultiLocation always has a canonical representation

runtime/common/src/xcm_sender.rs

@@ -19,7 +19,7 @@
 use parity_scale_codec::Encode;
 use runtime_parachains::{configuration, dmp};
 use sp_std::marker::PhantomData;
-use xcm::opaque::v1::{Error, Junction, MultiLocation, Result, SendXcm, Xcm};
+use xcm::opaque::latest::*;
 
 /// XCM sender for relay chain. It only sends downward message.
 pub struct ChildParachainRouter<T, W>(PhantomData<(T, W)>);
@@ -28,21 +28,21 @@ impl<T: configuration::Config + dmp::Config, W: xcm::WrapVersion> SendXcm
 	for ChildParachainRouter<T, W>
 {
 	fn send_xcm(dest: MultiLocation, msg: Xcm) -> Result {
-		match &dest {
-			MultiLocation::X1(Junction::Parachain(id)) => {
+		match dest {
+			MultiLocation { parents: 0, interior: Junctions::X1(Junction::Parachain(id)) } => {
 				// Downward message passing.
 				let versioned_xcm =
 					W::wrap_version(&dest, msg).map_err(|()| Error::DestinationUnsupported)?;
 				let config = <configuration::Pallet<T>>::config();
 				<dmp::Pallet<T>>::queue_downward_message(
 					&config,
-					(*id).into(),
+					id.into(),
 					versioned_xcm.encode(),
 				)
 				.map_err(Into::<Error>::into)?;
 				Ok(())
 			},
-			_ => Err(Error::CannotReachDestination(dest, msg)),
+			dest => Err(Error::CannotReachDestination(dest, msg)),
 		}
 	}
 }

runtime/kusama/src/lib.rs

@@ -1203,12 +1203,12 @@ parameter_types! {
 	/// The location of the KSM token, from the context of this chain. Since this token is native to this
 	/// chain, we make it synonymous with it and thus it is the `Here` location, which means "equivalent to
 	/// the context".
-	pub const KsmLocation: MultiLocation = MultiLocation::Here;
+	pub const KsmLocation: MultiLocation = Here.into();
 	/// The Kusama network ID. This is named.
 	pub const KusamaNetwork: NetworkId = NetworkId::Kusama;
 	/// Our XCM location ancestry - i.e. what, if anything, `Parent` means evaluated in our context. Since
 	/// Kusama is a top-level relay-chain, there is no ancestry.
-	pub const Ancestry: MultiLocation = MultiLocation::Here;
+	pub const Ancestry: MultiLocation = Here.into();
 	/// The check account, which holds any native assets that have been teleported out and not back in (yet).
 	pub CheckAccount: AccountId = XcmPallet::check_account();
 }
@@ -1265,7 +1265,7 @@ pub type XcmRouter = (
 
 parameter_types! {
 	pub const Kusama: MultiAssetFilter = Wild(AllOf { fun: WildFungible, id: Concrete(KsmLocation::get()) });
-	pub const KusamaForStatemint: (MultiAssetFilter, MultiLocation) = (Kusama::get(), X1(Parachain(1000)));
+	pub const KusamaForStatemint: (MultiAssetFilter, MultiLocation) = (Kusama::get(), Parachain(1000).into());
 }
 pub type TrustedTeleporters = (xcm_builder::Case<KusamaForStatemint>,);
 

runtime/rococo/src/lib.rs

@@ -583,9 +583,9 @@ impl parachains_paras::Config for Runtime {
 }
 
 parameter_types! {
-	pub const RocLocation: MultiLocation = MultiLocation::Here;
+	pub const RocLocation: MultiLocation = Here.into();
 	pub const RococoNetwork: NetworkId = NetworkId::Polkadot;
-	pub const Ancestry: MultiLocation = MultiLocation::Here;
+	pub const Ancestry: MultiLocation = Here.into();
 	pub CheckAccount: AccountId = XcmPallet::check_account();
 }
 
@@ -625,10 +625,10 @@ pub type XcmRouter = (
 
 parameter_types! {
 	pub const Rococo: MultiAssetFilter = Wild(AllOf { fun: WildFungible, id: Concrete(RocLocation::get()) });
-	pub const RococoForTick: (MultiAssetFilter, MultiLocation) = (Rococo::get(), X1(Parachain(100)));
-	pub const RococoForTrick: (MultiAssetFilter, MultiLocation) = (Rococo::get(), X1(Parachain(110)));
-	pub const RococoForTrack: (MultiAssetFilter, MultiLocation) = (Rococo::get(), X1(Parachain(120)));
-	pub const RococoForStatemint: (MultiAssetFilter, MultiLocation) = (Rococo::get(), X1(Parachain(1001)));
+	pub const RococoForTick: (MultiAssetFilter, MultiLocation) = (Rococo::get(), Parachain(100).into());
+	pub const RococoForTrick: (MultiAssetFilter, MultiLocation) = (Rococo::get(), Parachain(110).into());
+	pub const RococoForTrack: (MultiAssetFilter, MultiLocation) = (Rococo::get(), Parachain(120).into());
+	pub const RococoForStatemint: (MultiAssetFilter, MultiLocation) = (Rococo::get(), Parachain(1001).into());
 }
 pub type TrustedTeleporters = (
 	xcm_builder::Case<RococoForTick>,
@@ -640,10 +640,10 @@ pub type TrustedTeleporters = (
 parameter_types! {
 	pub AllowUnpaidFrom: Vec<MultiLocation> =
 		vec![
-			X1(Parachain(100)),
-			X1(Parachain(110)),
-			X1(Parachain(120)),
-			X1(Parachain(1001))
+			Parachain(100).into(),
+			Parachain(110).into(),
+			Parachain(120).into(),
+			Parachain(1001).into(),
 		];
 }
 

runtime/test-runtime/src/xcm_config.rs

@@ -16,8 +16,7 @@
 
 use frame_support::{parameter_types, traits::Everything, weights::Weight};
 use xcm::latest::{
-	Error as XcmError, Junction::*, MultiAsset, MultiLocation, MultiLocation::*, NetworkId,
-	Result as XcmResult, SendXcm, Xcm,
+	Error as XcmError, MultiAsset, MultiLocation, NetworkId, Result as XcmResult, SendXcm, Xcm, Parent, Junctions::Here,
 };
 use xcm_builder::{AllowUnpaidExecutionFrom, FixedWeightBounds, SignedToAccountId32};
 use xcm_executor::{
@@ -52,7 +51,7 @@ impl TransactAsset for DummyAssetTransactor {
 	}
 
 	fn withdraw_asset(_what: &MultiAsset, _who: &MultiLocation) -> Result<Assets, XcmError> {
-		let asset: MultiAsset = (X1(Parent), 100_000).into();
+		let asset: MultiAsset = (Parent, 100_000).into();
 		Ok(asset.into())
 	}
 }
@@ -71,7 +70,7 @@ impl WeightTrader for DummyWeightTrader {
 pub struct InvertNothing;
 impl InvertLocation for InvertNothing {
 	fn invert_location(_: &MultiLocation) -> MultiLocation {
-		MultiLocation::Here
+		Here.into()
 	}
 }
 

runtime/westend/src/lib.rs

@@ -866,8 +866,8 @@ impl auctions::Config for Runtime {
 }
 
 parameter_types! {
-	pub const WndLocation: MultiLocation = MultiLocation::Here;
-	pub const Ancestry: MultiLocation = MultiLocation::Here;
+	pub const WndLocation: MultiLocation = Here.into();
+	pub const Ancestry: MultiLocation = Here.into();
 	pub WestendNetwork: NetworkId = NetworkId::Named(b"Westend".to_vec());
 	pub CheckAccount: AccountId = XcmPallet::check_account();
 }
@@ -908,7 +908,7 @@ pub type XcmRouter = (
 
 parameter_types! {
 	pub const WestendForWestmint: (MultiAssetFilter, MultiLocation) =
-		(Wild(AllOf { fun: WildFungible, id: Concrete(WndLocation::get()) }), X1(Parachain(1000)));
+		(Wild(AllOf { fun: WildFungible, id: Concrete(WndLocation::get()) }), Parachain(1000).into());
 }
 pub type TrustedTeleporters = (xcm_builder::Case<WestendForWestmint>,);
 

xcm/pallet-xcm/src/lib.rs

@@ -102,7 +102,7 @@ pub mod pallet {
 		UnweighableMessage,
 		/// The assets to be sent are empty.
 		Empty,
-		/// Could not reanchor the assets to declare the fees for the destination chain.
+		/// Could not re-anchor the assets to declare the fees for the destination chain.
 		CannotReanchor,
 		/// Too many assets have been attempted for transfer.
 		TooManyAssets,
@@ -306,9 +306,10 @@ pub mod pallet {
 			dest: MultiLocation,
 			message: Xcm<()>,
 		) -> Result<(), XcmError> {
-			let message = match interior {
-				MultiLocation::Here => message,
-				who => Xcm::<()>::RelayedFrom { who, message: Box::new(message) },
+			let message = if interior.is_here() {
+				message
+			} else {
+				Xcm::<()>::RelayedFrom { who: interior, message: Box::new(message) }
 			};
 			log::trace!(target: "xcm::send_xcm", "dest: {:?}, message: {:?}", &dest, &message);
 			T::XcmRouter::send_xcm(dest, message)
@@ -384,7 +385,7 @@ where
 
 	#[cfg(feature = "runtime-benchmarks")]
 	fn successful_origin() -> O {
-		O::from(Origin::Xcm(MultiLocation::Here))
+		O::from(Origin::Xcm(Here.into()))
 	}
 }
 
@@ -393,9 +394,9 @@ where
 pub struct XcmPassthrough<Origin>(PhantomData<Origin>);
 impl<Origin: From<crate::Origin>> ConvertOrigin<Origin> for XcmPassthrough<Origin> {
 	fn convert_origin(origin: MultiLocation, kind: OriginKind) -> Result<Origin, MultiLocation> {
-		match (kind, origin) {
-			(OriginKind::Xcm, l) => Ok(crate::Origin::Xcm(l).into()),
-			(_, origin) => Err(origin),
+		match kind {
+			OriginKind::Xcm => Ok(crate::Origin::Xcm(origin).into()),
+			_ => Err(origin),
 		}
 	}
 }

xcm/pallet-xcm/src/mock.rs

@@ -71,7 +71,7 @@ impl SendXcm for TestSendXcm {
 pub struct TestSendXcmErrX8;
 impl SendXcm for TestSendXcmErrX8 {
 	fn send_xcm(dest: MultiLocation, msg: Xcm) -> XcmResult {
-		if let MultiLocation::X8(..) = dest {
+		if dest.len() == 8 {
 			Err(XcmError::Undefined)
 		} else {
 			SENT_XCM.with(|q| q.borrow_mut().push((dest, msg)));
@@ -129,9 +129,9 @@ impl pallet_balances::Config for Test {
 }
 
 parameter_types! {
-	pub const RelayLocation: MultiLocation = MultiLocation::Here;
+	pub const RelayLocation: MultiLocation = Here.into();
 	pub const AnyNetwork: NetworkId = NetworkId::Any;
-	pub Ancestry: MultiLocation = MultiLocation::Here;
+	pub Ancestry: MultiLocation = Here.into();
 	pub UnitWeightCost: Weight = 1_000;
 }
 

xcm/pallet-xcm/src/tests.rs

@@ -40,7 +40,7 @@ fn send_works() {
 		let sender: MultiLocation =
 			AccountId32 { network: AnyNetwork::get(), id: ALICE.into() }.into();
 		let message = Xcm::ReserveAssetDeposited {
-			assets: (X1(Parent), SEND_AMOUNT).into(),
+			assets: (Parent, SEND_AMOUNT).into(),
 			effects: vec![
 				buy_execution((Parent, SEND_AMOUNT), weight),
 				DepositAsset { assets: All.into(), max_assets: 1, beneficiary: sender.clone() },
@@ -54,7 +54,7 @@ fn send_works() {
 		assert_eq!(
 			sent_xcm(),
 			vec![(
-				MultiLocation::Here,
+				Here.into(),
 				RelayedFrom { who: sender.clone(), message: Box::new(message.clone()) }
 			)]
 		);
@@ -87,16 +87,7 @@ fn send_fails_when_xcm_router_blocks() {
 		assert_noop!(
 			XcmPallet::send(
 				Origin::signed(ALICE),
-				Box::new(X8(
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent,
-					Junction::Parent
-				)),
+				Box::new(MultiLocation::ancestor(8)),
 				Box::new(message.clone())
 			),
 			crate::Error::<Test>::SendFailure
@@ -118,7 +109,7 @@ fn teleport_assets_works() {
 		assert_ok!(XcmPallet::teleport_assets(
 			Origin::signed(ALICE),
 			Box::new(RelayLocation::get()),
-			Box::new(X1(AccountId32 { network: Any, id: BOB.into() })),
+			Box::new(AccountId32 { network: Any, id: BOB.into() }.into()),
 			(Here, SEND_AMOUNT).into(),
 			0,
 			weight,
@@ -162,7 +153,7 @@ fn reserve_transfer_assets_works() {
 			vec![(
 				Parachain(PARA_ID).into(),
 				Xcm::ReserveAssetDeposited {
-					assets: (X1(Parent), SEND_AMOUNT).into(),
+					assets: (Parent, SEND_AMOUNT).into(),
 					effects: vec![
 						buy_execution((Parent, SEND_AMOUNT), weight),
 						DepositAsset { assets: All.into(), max_assets: 1, beneficiary: dest },