XCMv5 asset exchange test scenarios

cumulus/parachains/integration-tests/emulated/tests/assets/asset-hub-westend/src/lib.rs

@@ -44,8 +44,10 @@ mod imports {
 			TestArgs, TestContext, TestExt,
 		},
 		xcm_helpers::{
-			fee_asset, get_amount_from_versioned_assets, non_fee_asset, xcm_transact_paid_execution,
+			fee_asset, find_mq_processed_id, find_xcm_sent_message_id,
+			get_amount_from_versioned_assets, non_fee_asset, xcm_transact_paid_execution,
 		},
+		xcm_simulator::helpers::TopicIdTracker,
 		PenpalATeleportableAssetLocation, ASSETS_PALLET_ID, RESERVABLE_ASSET_ID, USDT_ID, XCM_V3,
 	};
 	pub(crate) use parachains_common::{AccountId, Balance};

cumulus/parachains/integration-tests/emulated/tests/assets/asset-hub-westend/src/tests/exchange_asset.rs

@@ -14,7 +14,7 @@
 // limitations under the License.
 
 use crate::{
-	create_pool_with_wnd_on,
+	assets_balance_on, create_pool_with_wnd_on, foreign_balance_on,
 	imports::{
 		asset_hub_westend_runtime::{ExistentialDeposit, Runtime},
 		*,
@@ -156,3 +156,173 @@ fn test_exchange_asset(
 		}
 	});
 }
+
+#[test]
+fn exchange_asset_from_penpal_via_asset_hub_back_to_penpal() {
+	let sender = PenpalASender::get();
+	let sov_of_penpal_on_asset_hub = AssetHubWestend::sovereign_account_id_of(
+		AssetHubWestend::sibling_location_of(PenpalA::para_id()),
+	);
+	let wnd_from_parachain_pov: Location = RelayLocation::get();
+	let usdt_asset_hub_pov =
+		Location::new(0, [PalletInstance(ASSETS_PALLET_ID), GeneralIndex(USDT_ID.into())]);
+	let usdt_penpal_pov = PenpalUsdtFromAssetHub::get();
+	let amount_of_wnd_to_transfer_to_ah = WESTEND_ED * 1_000_000_000;
+	let amount_of_usdt_we_want_from_exchange = 1_000_000_000;
+
+	let mut topic_id_tracker = TopicIdTracker::new();
+
+	// SA-of-Penpal-on-AHW should contain WND amount equal at least the amount that will be
+	// transferred-in to AH Since AH is the reserve for WND
+	AssetHubWestend::fund_accounts(vec![(
+		sov_of_penpal_on_asset_hub.clone().into(),
+		ASSET_HUB_WESTEND_ED + amount_of_wnd_to_transfer_to_ah,
+	)]);
+	// Give the sender enough WND
+	PenpalA::mint_foreign_asset(
+		<PenpalA as Chain>::RuntimeOrigin::signed(PenpalAssetOwner::get()),
+		wnd_from_parachain_pov.clone(),
+		sender.clone(),
+		amount_of_wnd_to_transfer_to_ah,
+	);
+
+	// We create a pool between WND and USDT in AssetHub so we can do the exchange
+	create_pool_with_wnd_on!(
+		AssetHubWestend,
+		usdt_asset_hub_pov.clone(),
+		false,
+		AssetHubWestendSender::get(),
+		1_000_000_000_000,
+		20_000_000_000
+	);
+
+	// Query initial balances
+	let sender_usdt_on_penpal_before =
+		foreign_balance_on!(PenpalA, usdt_penpal_pov.clone(), &sender);
+	let sender_usdt_on_ah_before = assets_balance_on!(AssetHubWestend, USDT_ID, &sender);
+
+	let asset_hub_location_penpal_pov = PenpalA::sibling_location_of(AssetHubWestend::para_id());
+	let penpal_location_ah_pov = AssetHubWestend::sibling_location_of(PenpalA::para_id());
+
+	PenpalA::execute_with(|| {
+		let sender_signed_origin = <PenpalA as Chain>::RuntimeOrigin::signed(sender.clone());
+
+		let local_fees_amount = 80_000_000_000_000u128;
+		let remote_fees_amount = 200_000_000_000_000u128;
+
+		let penpal_local_fees: Asset = (wnd_from_parachain_pov.clone(), local_fees_amount).into();
+		let ah_remote_fees: Asset = (wnd_from_parachain_pov.clone(), remote_fees_amount).into();
+		let penpal_remote_fees: Asset = (wnd_from_parachain_pov.clone(), remote_fees_amount).into();
+		let wnd_to_withdraw: Asset =
+			(wnd_from_parachain_pov.clone(), amount_of_wnd_to_transfer_to_ah).into();
+
+		// xcm to be executed by penpal, sent by ah
+		let xcm_back_on_penpal = Xcm(vec![
+			RefundSurplus,
+			DepositAsset { assets: Wild(All), beneficiary: sender.clone().into() },
+		]);
+		// xcm to be executed by ah, sent by penpal
+		let xcm_on_ah = Xcm(vec![
+			ExchangeAsset {
+				give: Definite((wnd_from_parachain_pov.clone(), 100_000_000_000u128).into()),
+				want: (usdt_asset_hub_pov.clone(), amount_of_usdt_we_want_from_exchange).into(),
+				maximal: false,
+			},
+			InitiateTransfer {
+				destination: penpal_location_ah_pov,
+				remote_fees: Some(AssetTransferFilter::ReserveDeposit(
+					penpal_remote_fees.clone().into(),
+				)),
+				preserve_origin: false,
+				assets: BoundedVec::truncate_from(vec![AssetTransferFilter::ReserveDeposit(Wild(
+					All,
+				))]),
+				remote_xcm: xcm_back_on_penpal,
+			},
+			RefundSurplus,
+			DepositAsset { assets: Wild(All), beneficiary: sender.clone().into() },
+		]);
+		// xcm to be executed locally on penpal as starting point
+		let xcm = Xcm::<()>(vec![
+			WithdrawAsset(wnd_to_withdraw.into()),
+			PayFees { asset: penpal_local_fees },
+			InitiateTransfer {
+				destination: asset_hub_location_penpal_pov,
+				remote_fees: Some(AssetTransferFilter::ReserveWithdraw(
+					ah_remote_fees.clone().into(),
+				)),
+				preserve_origin: false,
+				assets: BoundedVec::truncate_from(vec![AssetTransferFilter::ReserveWithdraw(
+					Wild(All),
+				)]),
+				remote_xcm: xcm_on_ah,
+			},
+			RefundSurplus,
+			DepositAsset { assets: Wild(All), beneficiary: sender.clone().into() },
+		]);
+		// initiate transaction
+		<PenpalA as PenpalAPallet>::PolkadotXcm::execute(
+			sender_signed_origin,
+			bx!(xcm::VersionedXcm::from(xcm.into())),
+			Weight::MAX,
+		)
+		.unwrap();
+
+		// verify expected events;
+		PenpalA::assert_xcm_pallet_attempted_complete(None);
+
+		let msg_sent_id = find_xcm_sent_message_id::<PenpalA>().expect("Missing Sent Event");
+		topic_id_tracker.insert("PenpalA_sent", msg_sent_id.into());
+	});
+	AssetHubWestend::execute_with(|| {
+		type RuntimeEvent = <AssetHubWestend as Chain>::RuntimeEvent;
+		assert_expected_events!(
+			AssetHubWestend,
+			vec![
+				RuntimeEvent::MessageQueue(
+					pallet_message_queue::Event::Processed { success: true, .. }
+				) => {},
+				RuntimeEvent::AssetConversion(
+					pallet_asset_conversion::Event::SwapCreditExecuted { amount_out, ..}
+				) => { amount_out: *amount_out == amount_of_usdt_we_want_from_exchange, },
+			]
+		);
+
+		let mq_prc_id = find_mq_processed_id::<AssetHubWestend>().expect("Missing Processed Event");
+		topic_id_tracker.insert("AssetHubWestend_received", mq_prc_id);
+		let msg_sent_id =
+			find_xcm_sent_message_id::<AssetHubWestend>().expect("Missing Sent Event");
+		topic_id_tracker.insert("AssetHubWestend_sent", msg_sent_id.into());
+	});
+
+	PenpalA::execute_with(|| {
+		type RuntimeEvent = <PenpalA as Chain>::RuntimeEvent;
+		assert_expected_events!(
+			PenpalA,
+			vec![
+				RuntimeEvent::MessageQueue(
+					pallet_message_queue::Event::Processed { success: true, .. }
+				) => {},
+			]
+		);
+
+		let mq_prc_id = find_mq_processed_id::<PenpalA>().expect("Missing Processed Event");
+		topic_id_tracker.insert("PenpalA_received", mq_prc_id);
+	});
+
+	topic_id_tracker.assert_unique();
+
+	// Query final balances
+	let sender_usdt_on_ah_after = assets_balance_on!(AssetHubWestend, USDT_ID, &sender);
+	let sender_usdt_on_penpal_after =
+		foreign_balance_on!(PenpalA, usdt_penpal_pov.clone(), &sender);
+
+	// Receiver's balance is increased by usdt amount we got from exchange
+	assert_eq!(
+		sender_usdt_on_penpal_after,
+		sender_usdt_on_penpal_before + amount_of_usdt_we_want_from_exchange
+	);
+	// Usdt amount on senders account AH side should stay the same i.e. all usdt came from exchange
+	// not free balance
+	assert_eq!(sender_usdt_on_ah_before, sender_usdt_on_ah_after);
+}

cumulus/parachains/integration-tests/emulated/tests/assets/asset-hub-westend/src/tests/mod.rs

@@ -36,7 +36,19 @@ macro_rules! foreign_balance_on {
 		emulated_integration_tests_common::impls::paste::paste! {
 			<$chain>::execute_with(|| {
 				type ForeignAssets = <$chain as [<$chain Pallet>]>::ForeignAssets;
-				<ForeignAssets as Inspect<_>>::balance($id, $who)
+				<ForeignAssets as frame_support::traits::fungibles::Inspect<_>>::balance($id, $who)
+			})
+		}
+	};
+}
+
+#[macro_export]
+macro_rules! assets_balance_on {
+	( $chain:ident, $id:expr, $who:expr ) => {
+		emulated_integration_tests_common::impls::paste::paste! {
+			<$chain>::execute_with(|| {
+				type Assets = <$chain as [<$chain Pallet>]>::Assets;
+				<Assets as frame_support::traits::fungibles::Inspect<_>>::balance($id, $who)
 			})
 		}
 	};