NonReserve case support teleport

xtokens/src/lib.rs

@@ -21,6 +21,7 @@
 #![allow(clippy::from_over_into)]
 #![allow(clippy::unused_unit)]
 #![allow(clippy::large_enum_variant)]
+#![allow(clippy::too_many_arguments)]
 
 use frame_support::{
 	log,
@@ -561,6 +562,9 @@ pub mod module {
 				assets_to_fee_reserve.push(asset_to_fee_reserve.clone());
 
 				// First xcm sent to fee reserve chain and routed to dest chain.
+				// We can use `MinXcmFee` configuration to decide which target parachain use
+				// teleport. But as current there's only one case which is Parachain send back
+				// asset to Statemine/t, So we set `use_teleport` to always `true` in this case.
 				Self::execute_and_send_reserve_kind_xcm(
 					origin_location.clone(),
 					assets_to_fee_reserve,
@@ -569,6 +573,7 @@ pub mod module {
 					&dest,
 					Some(T::SelfLocation::get()),
 					dest_weight,
+					true,
 				)?;
 
 				// Second xcm send to dest chain.
@@ -580,6 +585,7 @@ pub mod module {
 					&dest,
 					None,
 					dest_weight,
+					false,
 				)?;
 			} else {
 				Self::execute_and_send_reserve_kind_xcm(
@@ -590,6 +596,7 @@ pub mod module {
 					&dest,
 					None,
 					dest_weight,
+					false,
 				)?;
 			}
 
@@ -613,6 +620,7 @@ pub mod module {
 			dest: &MultiLocation,
 			maybe_recipient_override: Option<MultiLocation>,
 			dest_weight: Weight,
+			use_teleport: bool,
 		) -> DispatchResult {
 			let (transfer_kind, dest, reserve, recipient) = Self::transfer_kind(reserve, dest)?;
 			let recipient = match maybe_recipient_override {
@@ -623,7 +631,9 @@ pub mod module {
 			let mut msg = match transfer_kind {
 				SelfReserveAsset => Self::transfer_self_reserve_asset(assets, fee, dest, recipient, dest_weight)?,
 				ToReserve => Self::transfer_to_reserve(assets, fee, dest, recipient, dest_weight)?,
-				ToNonReserve => Self::transfer_to_non_reserve(assets, fee, reserve, dest, recipient, dest_weight)?,
+				ToNonReserve => {
+					Self::transfer_to_non_reserve(assets, fee, reserve, dest, recipient, dest_weight, use_teleport)?
+				}
 			};
 
 			let weight = T::Weigher::weight(&mut msg).map_err(|()| Error::<T>::UnweighableMessage)?;
@@ -681,6 +691,7 @@ pub mod module {
 			dest: MultiLocation,
 			recipient: MultiLocation,
 			dest_weight: Weight,
+			use_teleport: bool,
 		) -> Result<Xcm<T::Call>, DispatchError> {
 			let mut reanchored_dest = dest.clone();
 			if reserve == MultiLocation::parent() {
@@ -695,25 +706,46 @@ pub mod module {
 				}
 			}
 
-			Ok(Xcm(vec![
-				WithdrawAsset(assets.clone()),
-				InitiateReserveWithdraw {
-					assets: All.into(),
-					reserve: reserve.clone(),
-					xcm: Xcm(vec![
-						Self::buy_execution(half(&fee), &reserve, dest_weight)?,
-						DepositReserveAsset {
-							assets: All.into(),
-							max_assets: assets.len() as u32,
-							dest: reanchored_dest,
-							xcm: Xcm(vec![
-								Self::buy_execution(half(&fee), &dest, dest_weight)?,
-								Self::deposit_asset(recipient, assets.len() as u32),
-							]),
-						},
-					]),
-				},
-			]))
+			if !use_teleport {
+				Ok(Xcm(vec![
+					WithdrawAsset(assets.clone()),
+					InitiateReserveWithdraw {
+						assets: All.into(),
+						reserve: reserve.clone(),
+						xcm: Xcm(vec![
+							Self::buy_execution(half(&fee), &reserve, dest_weight)?,
+							DepositReserveAsset {
+								assets: All.into(),
+								max_assets: assets.len() as u32,
+								dest: reanchored_dest,
+								xcm: Xcm(vec![
+									Self::buy_execution(half(&fee), &dest, dest_weight)?,
+									Self::deposit_asset(recipient, assets.len() as u32),
+								]),
+							},
+						]),
+					},
+				]))
+			} else {
+				Ok(Xcm(vec![
+					WithdrawAsset(assets.clone()),
+					InitiateReserveWithdraw {
+						assets: All.into(),
+						reserve: reserve.clone(),
+						xcm: Xcm(vec![
+							Self::buy_execution(half(&fee), &reserve, dest_weight)?,
+							InitiateTeleport {
+								assets: All.into(),
+								dest: reanchored_dest,
+								xcm: Xcm(vec![
+									Self::buy_execution(half(&fee), &dest, dest_weight)?,
+									Self::deposit_asset(recipient, assets.len() as u32),
+								]),
+							},
+						]),
+					},
+				]))
+			}
 		}
 
 		fn deposit_asset(recipient: MultiLocation, max_assets: u32) -> Instruction<()> {

xtokens/src/mock/mod.rs

@@ -7,12 +7,16 @@ use scale_info::TypeInfo;
 use serde::{Deserialize, Serialize};
 use sp_io::TestExternalities;
 use sp_runtime::AccountId32;
+use xcm_executor::traits::WeightTrader;
+use xcm_executor::Assets;
 
 use xcm_simulator::{decl_test_network, decl_test_parachain, decl_test_relay_chain};
 
 pub mod para;
 pub mod para_relative_view;
+pub mod para_teleport;
 pub mod relay;
+pub mod teleport_currency_adapter;
 
 pub const ALICE: AccountId32 = AccountId32::new([0u8; 32]);
 pub const BOB: AccountId32 = AccountId32::new([1u8; 32]);
@@ -32,6 +36,8 @@ pub enum CurrencyId {
 	B1,
 	/// Parachain B B2 token
 	B2,
+	/// Parachain C token
+	C,
 	/// Parachain D token
 	D,
 }
@@ -46,6 +52,7 @@ impl Convert<CurrencyId, Option<MultiLocation>> for CurrencyIdConvert {
 			CurrencyId::B => Some((Parent, Parachain(2), GeneralKey("B".into())).into()),
 			CurrencyId::B1 => Some((Parent, Parachain(2), GeneralKey("B1".into())).into()),
 			CurrencyId::B2 => Some((Parent, Parachain(2), GeneralKey("B2".into())).into()),
+			CurrencyId::C => Some((Parent, Parachain(3), GeneralKey("C".into())).into()),
 			CurrencyId::D => Some((Parent, Parachain(4), GeneralKey("D".into())).into()),
 		}
 	}
@@ -57,6 +64,7 @@ impl Convert<MultiLocation, Option<CurrencyId>> for CurrencyIdConvert {
 		let b: Vec<u8> = "B".into();
 		let b1: Vec<u8> = "B1".into();
 		let b2: Vec<u8> = "B2".into();
+		let c: Vec<u8> = "C".into();
 		let d: Vec<u8> = "D".into();
 		if l == MultiLocation::parent() {
 			return Some(CurrencyId::R);
@@ -68,6 +76,7 @@ impl Convert<MultiLocation, Option<CurrencyId>> for CurrencyIdConvert {
 				X2(Parachain(2), GeneralKey(k)) if k == b => Some(CurrencyId::B),
 				X2(Parachain(2), GeneralKey(k)) if k == b1 => Some(CurrencyId::B1),
 				X2(Parachain(2), GeneralKey(k)) if k == b2 => Some(CurrencyId::B2),
+				X2(Parachain(3), GeneralKey(k)) if k == c => Some(CurrencyId::C),
 				X2(Parachain(4), GeneralKey(k)) if k == d => Some(CurrencyId::D),
 				_ => None,
 			},
@@ -77,6 +86,7 @@ impl Convert<MultiLocation, Option<CurrencyId>> for CurrencyIdConvert {
 				X1(GeneralKey(k)) if k == a1 => Some(CurrencyId::A1),
 				X1(GeneralKey(k)) if k == b1 => Some(CurrencyId::B1),
 				X1(GeneralKey(k)) if k == b2 => Some(CurrencyId::B2),
+				X1(GeneralKey(k)) if k == c => Some(CurrencyId::C),
 				X1(GeneralKey(k)) if k == d => Some(CurrencyId::D),
 				_ => None,
 			},
@@ -121,10 +131,10 @@ decl_test_parachain! {
 
 decl_test_parachain! {
 	pub struct ParaC {
-		Runtime = para::Runtime,
-		XcmpMessageHandler = para::XcmpQueue,
-		DmpMessageHandler = para::DmpQueue,
-		new_ext = para_ext(3),
+		Runtime = para_teleport::Runtime,
+		XcmpMessageHandler = para_teleport::XcmpQueue,
+		DmpMessageHandler = para_teleport::DmpQueue,
+		new_ext = para_teleport_ext(3),
 	}
 }
 
@@ -166,6 +176,8 @@ pub type ParaXTokens = orml_xtokens::Pallet<para::Runtime>;
 pub type ParaRelativeTokens = orml_tokens::Pallet<para_relative_view::Runtime>;
 pub type ParaRelativeXTokens = orml_xtokens::Pallet<para_relative_view::Runtime>;
 
+pub type ParaTeleportTokens = orml_tokens::Pallet<para_teleport::Runtime>;
+
 pub fn para_ext(para_id: u32) -> TestExternalities {
 	use para::{Runtime, System};
 
@@ -190,6 +202,30 @@ pub fn para_ext(para_id: u32) -> TestExternalities {
 	ext
 }
 
+pub fn para_teleport_ext(para_id: u32) -> TestExternalities {
+	use para_teleport::{Runtime, System};
+
+	let mut t = frame_system::GenesisConfig::default()
+		.build_storage::<Runtime>()
+		.unwrap();
+
+	let parachain_info_config = parachain_info::GenesisConfig {
+		parachain_id: para_id.into(),
+	};
+	<parachain_info::GenesisConfig as GenesisBuild<Runtime, _>>::assimilate_storage(&parachain_info_config, &mut t)
+		.unwrap();
+
+	orml_tokens::GenesisConfig::<Runtime> {
+		balances: vec![(ALICE, CurrencyId::R, 1_000)],
+	}
+	.assimilate_storage(&mut t)
+	.unwrap();
+
+	let mut ext = TestExternalities::new(t);
+	ext.execute_with(|| System::set_block_number(1));
+	ext
+}
+
 pub fn relay_ext() -> sp_io::TestExternalities {
 	use relay::{Runtime, System};
 
@@ -207,3 +243,46 @@ pub fn relay_ext() -> sp_io::TestExternalities {
 	ext.execute_with(|| System::set_block_number(1));
 	ext
 }
+
+/// A trader who believes all tokens are created equal to "weight" of any chain,
+/// which is not true, but good enough to mock the fee payment of XCM execution.
+///
+/// This mock will always trade `n` amount of weight to `n` amount of tokens.
+pub struct AllTokensAreCreatedEqualToWeight(MultiLocation);
+impl WeightTrader for AllTokensAreCreatedEqualToWeight {
+	fn new() -> Self {
+		Self(MultiLocation::parent())
+	}
+
+	fn buy_weight(&mut self, weight: Weight, payment: Assets) -> Result<Assets, XcmError> {
+		let asset_id = payment
+			.fungible
+			.iter()
+			.next()
+			.expect("Payment must be something; qed")
+			.0;
+		let required = MultiAsset {
+			id: asset_id.clone(),
+			fun: Fungible(weight as u128),
+		};
+
+		if let MultiAsset {
+			fun: _,
+			id: Concrete(ref id),
+		} = &required
+		{
+			self.0 = id.clone();
+		}
+
+		let unused = payment.checked_sub(required).map_err(|_| XcmError::TooExpensive)?;
+		Ok(unused)
+	}
+
+	fn refund_weight(&mut self, weight: Weight) -> Option<MultiAsset> {
+		if weight.is_zero() {
+			None
+		} else {
+			Some((self.0.clone(), weight as u128).into())
+		}
+	}
+}

xtokens/src/mock/para.rs

@@ -10,7 +10,7 @@ use frame_system::EnsureRoot;
 use sp_core::H256;
 use sp_runtime::{
 	testing::Header,
-	traits::{Convert, IdentityLookup, Zero},
+	traits::{Convert, IdentityLookup},
 	AccountId32,
 };
 
@@ -20,11 +20,12 @@ use polkadot_parachain::primitives::Sibling;
 use xcm::latest::prelude::*;
 use xcm_builder::{
 	AccountId32Aliases, AllowTopLevelPaidExecutionFrom, EnsureXcmOrigin, FixedWeightBounds, LocationInverter,
-	ParentIsPreset, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
+	NativeAsset, ParentIsPreset, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
 	SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit,
 };
-use xcm_executor::{traits::WeightTrader, Assets, Config, XcmExecutor};
+use xcm_executor::{Config, XcmExecutor};
 
+use crate::mock::AllTokensAreCreatedEqualToWeight;
 use orml_traits::{location::AbsoluteReserveProvider, parameter_type_with_key};
 use orml_xcm_support::{IsNativeConcrete, MultiCurrencyAdapter, MultiNativeAsset};
 
@@ -133,57 +134,14 @@ pub type LocalAssetTransactor = MultiCurrencyAdapter<
 pub type XcmRouter = ParachainXcmRouter<ParachainInfo>;
 pub type Barrier = (TakeWeightCredit, AllowTopLevelPaidExecutionFrom<Everything>);
 
-/// A trader who believes all tokens are created equal to "weight" of any chain,
-/// which is not true, but good enough to mock the fee payment of XCM execution.
-///
-/// This mock will always trade `n` amount of weight to `n` amount of tokens.
-pub struct AllTokensAreCreatedEqualToWeight(MultiLocation);
-impl WeightTrader for AllTokensAreCreatedEqualToWeight {
-	fn new() -> Self {
-		Self(MultiLocation::parent())
-	}
-
-	fn buy_weight(&mut self, weight: Weight, payment: Assets) -> Result<Assets, XcmError> {
-		let asset_id = payment
-			.fungible
-			.iter()
-			.next()
-			.expect("Payment must be something; qed")
-			.0;
-		let required = MultiAsset {
-			id: asset_id.clone(),
-			fun: Fungible(weight as u128),
-		};
-
-		if let MultiAsset {
-			fun: _,
-			id: Concrete(ref id),
-		} = &required
-		{
-			self.0 = id.clone();
-		}
-
-		let unused = payment.checked_sub(required).map_err(|_| XcmError::TooExpensive)?;
-		Ok(unused)
-	}
-
-	fn refund_weight(&mut self, weight: Weight) -> Option<MultiAsset> {
-		if weight.is_zero() {
-			None
-		} else {
-			Some((self.0.clone(), weight as u128).into())
-		}
-	}
-}
-
 pub struct XcmConfig;
 impl Config for XcmConfig {
 	type Call = Call;
 	type XcmSender = XcmRouter;
 	type AssetTransactor = LocalAssetTransactor;
 	type OriginConverter = XcmOriginToCallOrigin;
 	type IsReserve = MultiNativeAsset<AbsoluteReserveProvider>;
-	type IsTeleporter = ();
+	type IsTeleporter = NativeAsset;
 	type LocationInverter = LocationInverter<Ancestry>;
 	type Barrier = Barrier;
 	type Weigher = FixedWeightBounds<ConstU64<10>, Call, ConstU32<100>>;
@@ -277,7 +235,7 @@ parameter_type_with_key! {
 	pub ParachainMinFee: |location: MultiLocation| -> Option<u128> {
 		#[allow(clippy::match_ref_pats)] // false positive
 		match (location.parents, location.first_interior()) {
-			(1, Some(Parachain(2))) => Some(40),
+			(1, Some(Parachain(3))) => Some(40),
 			_ => None,
 		}
 	};