Statemine XCM Simulator Tests

Cargo.toml

@@ -42,6 +42,7 @@ members = [
 	"xcm/xcm-executor/integration-tests",
 	"xcm/xcm-simulator",
 	"xcm/xcm-simulator/example",
+	"xcm/xcm-simulator/statemine-like-example",
 	"xcm/pallet-xcm",
 	"xcm/procedural",
 	"node/client",

runtime/parachains/src/ump.rs

@@ -43,8 +43,9 @@ pub use pallet::*;
 /// It is possible that by the time the message is sank the origin parachain was offboarded. It is
 /// up to the implementer to check that if it cares.
 pub trait UmpSink {
-	/// Process an incoming upward message and return the amount of weight it consumed, or `None` if
-	/// it did not begin processing a message since it would otherwise exceed `max_weight`.
+	/// Process an incoming upward message and return the amount of weight it consumed, or
+	/// `Err(message_id, required_weight)` if it did not begin processing a message since it would
+	/// otherwise exceed `max_weight`.
 	///
 	/// See the trait docs for more details.
 	fn process_upward_message(
@@ -55,7 +56,7 @@ pub trait UmpSink {
 }
 
 /// An implementation of a sink that just swallows the message without consuming any weight. Returns
-/// `Some(0)` indicating that no messages existed for it to process.
+/// `Ok(0)` indicating that no messages existed for it to process.
 impl UmpSink for () {
 	fn process_upward_message(
 		_: ParaId,

xcm/xcm-simulator/example/src/lib.rs

@@ -83,6 +83,7 @@ pub fn para_ext(para_id: u32) -> sp_io::TestExternalities {
 
 pub fn relay_ext() -> sp_io::TestExternalities {
 	use relay_chain::{Runtime, System};
+	let para_account_a: relay_chain::AccountId = ParaId::from(1).into_account();
 
 	let mut t = frame_system::GenesisConfig::default().build_storage::<Runtime>().unwrap();
 
@@ -195,8 +196,12 @@ mod tests {
 		});
 	}
 
+	/// Scenario:
+	/// A user Alice sends funds from the relaychain to a parachain.
+	///
+	/// Asserts that the correct XCM is sent and the balances are set as expected.
 	#[test]
-	fn reserve_transfer() {
+	fn reserve_transfer_assets() {
 		MockNet::reset();
 
 		let withdraw_amount = 123;
@@ -216,7 +221,26 @@ mod tests {
 		});
 
 		ParaA::execute_with(|| {
-			// free execution, full amount received
+			// Check message received
+			let expected_message = (
+				X1(Parent),
+				ReserveAssetDeposit {
+					assets: vec![ConcreteFungible { id: X1(Parent), amount: withdraw_amount }],
+					effects: vec![
+						buy_execution(max_weight_for_execution),
+						Order::DepositAsset {
+							assets: All.into(),
+							max_assets: 1,
+							beneficiary: X1(Junction::AccountId32 {
+								network: NetworkId::Any,
+								id: ALICE.into(),
+							}).into(),
+						},
+					],
+				},
+			);
+			assert_eq!(parachain::MsgQueue::received_dmp(), vec![expected_message]);
+			// Check message execution with full amount received
 			assert_eq!(
 				pallet_balances::Pallet::<parachain::Runtime>::free_balance(&ALICE),
 				INITIAL_BALANCE + withdraw_amount

xcm/xcm-simulator/src/lib.rs

@@ -16,7 +16,7 @@
 
 //! Test kit to simulate cross-chain message passing and XCM execution
 
-pub use codec::Encode;
+pub use codec::{Decode, Encode};
 pub use paste;
 
 pub use frame_support::{traits::Get, weights::Weight};
@@ -219,7 +219,9 @@ macro_rules! decl_test_network {
 				$crate::RELAY_MESSAGE_BUS.with(|b| b.replace(VecDeque::new()));
 				// Reset parachain message bus
 				$crate::PARA_MESSAGE_BUS.with(|b| b.replace(VecDeque::new()));
+				// Reset relay chain state
 				<$relay_chain>::reset_ext();
+				// Reset parachain state
 				$( <$parachain>::reset_ext(); )*
 			}
 		}
@@ -319,6 +321,9 @@ macro_rules! decl_test_network {
 
 		/// XCM router for relay chain.
 		pub struct RelayChainXcmRouter;
+
+
+
 		impl $crate::SendXcm for RelayChainXcmRouter {
 			fn send_xcm(destination: $crate::MultiLocation, message: $crate::Xcm<()>) -> $crate::SendResult {
 				use $crate::DmpMessageHandlerT;

xcm/xcm-simulator/statemine-like-example/Cargo.toml

@@ -0,0 +1,29 @@
+[package]
+name = "xcm-statemine-like-example"
+version = "0.9.8"
+authors = ["Parity Technologies <admin@parity.io>"]
+description = "Examples of XCM interactions with a Statemine-like chain."
+edition = "2018"
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "2.0.0" }
+paste = "1.0.5"
+
+frame-system = { git = "https://github.com/paritytech/substrate", branch = "master" }
+frame-support = { git = "https://github.com/paritytech/substrate", branch = "master" }
+pallet-assets = { git = "https://github.com/paritytech/substrate", branch = "master" }
+pallet-balances = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-std = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-io = { git = "https://github.com/paritytech/substrate", branch = "master" }
+
+xcm = { path = "../../" }
+xcm-simulator = { path = "../" }
+xcm-executor = { path = "../../xcm-executor" }
+xcm-builder = { path = "../../xcm-builder" }
+pallet-xcm = { path = "../../pallet-xcm" }
+polkadot-core-primitives = { path = "../../../core-primitives"}
+polkadot-runtime-parachains = { path = "../../../runtime/parachains" }
+polkadot-parachain = { path = "../../../parachain" }
+