Improve Penpal runtime + emulated tests (#3543)

Issues addressed in this PR:
- Improve *Penpal* runtime:
- Properly handled received assets. Previously, it treated `(1, Here)`
as the local native currency, whereas it should be treated as a
`ForeignAsset`. This wasn't a great example of standard Parachain
behaviour, as no Parachain treats the system asset as the local
currency.
- Remove `AllowExplicitUnpaidExecutionFrom` the system. Again, this
wasn't a great example of standard Parachain behaviour.
- Move duplicated
`ForeignAssetFeeAsExistentialDepositMultiplierFeeCharger` to
`assets_common` crate.
- Improve emulated tests:
  - Update *Penpal* tests to new runtime.
- To simplify tests, register the reserve transferred, teleported, and
system assets in *Penpal* and *AssetHub* genesis. This saves us from
having to create the assets repeatedly for each test
- Add missing test case:
`reserve_transfer_assets_from_para_to_system_para`.
  - Cleanup.
- Prevent integration tests crates imports from being re-exported, as
they were polluting the `polkadot-sdk` docs.

There is still a test case missing for reserve transfers:
- Reserve transfer of system asset from *Parachain* to *Parachain*
trough *AssetHub*.
- This is not yet possible with `pallet-xcm` due to the reasons
explained in #3339

---------

Co-authored-by: command-bot <>

cumulus/parachains/integration-tests/emulated/chains/parachains/assets/asset-hub-rococo/src/genesis.rs

@@ -14,17 +14,24 @@
 // limitations under the License.
 
 // Substrate
-use sp_core::storage::Storage;
+use frame_support::parameter_types;
+use sp_core::{sr25519, storage::Storage};
 
 // Cumulus
 use emulated_integration_tests_common::{
-	accounts, build_genesis_storage, collators, SAFE_XCM_VERSION,
+	accounts, build_genesis_storage, collators, get_account_id_from_seed,
+	PenpalSiblingSovereigAccount, PenpalTeleportableAssetLocation, RESERVABLE_ASSET_ID,
+	SAFE_XCM_VERSION,
 };
-use parachains_common::Balance;
+use parachains_common::{AccountId, Balance};
 
 pub const PARA_ID: u32 = 1000;
 pub const ED: Balance = testnet_parachains_constants::rococo::currency::EXISTENTIAL_DEPOSIT;
 
+parameter_types! {
+	pub AssetHubRococoAssetOwner: AccountId = get_account_id_from_seed::<sr25519::Public>("Alice");
+}
+
 pub fn genesis() -> Storage {
 	let genesis_config = asset_hub_rococo_runtime::RuntimeGenesisConfig {
 		system: asset_hub_rococo_runtime::SystemConfig::default(),
@@ -60,6 +67,22 @@ pub fn genesis() -> Storage {
 			safe_xcm_version: Some(SAFE_XCM_VERSION),
 			..Default::default()
 		},
+		assets: asset_hub_rococo_runtime::AssetsConfig {
+			assets: vec![(RESERVABLE_ASSET_ID, AssetHubRococoAssetOwner::get(), true, ED)],
+			..Default::default()
+		},
+		foreign_assets: asset_hub_rococo_runtime::ForeignAssetsConfig {
+			assets: vec![
+				// Penpal's teleportable asset representation
+				(
+					PenpalTeleportableAssetLocation::get(),
+					PenpalSiblingSovereigAccount::get(),
+					true,
+					ED,
+				),
+			],
+			..Default::default()
+		},
 		..Default::default()
 	};
 

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

@@ -21,7 +21,7 @@ use frame_support::traits::OnInitialize;
 // Cumulus
 use emulated_integration_tests_common::{
 	impl_accounts_helpers_for_parachain, impl_assert_events_helpers_for_parachain,
-	impl_assets_helpers_for_parachain, impl_foreign_assets_helpers_for_parachain,
+	impl_assets_helpers_for_parachain, impl_assets_helpers_for_system_parachain,
 	impl_xcm_helpers_for_parachain, impls::Parachain, xcm_emulator::decl_test_parachains,
 };
 use rococo_emulated_chain::Rococo;
@@ -54,6 +54,6 @@ decl_test_parachains! {
 // AssetHubRococo implementation
 impl_accounts_helpers_for_parachain!(AssetHubRococo);
 impl_assert_events_helpers_for_parachain!(AssetHubRococo);
-impl_assets_helpers_for_parachain!(AssetHubRococo, Rococo);
-impl_foreign_assets_helpers_for_parachain!(AssetHubRococo, Rococo);
+impl_assets_helpers_for_system_parachain!(AssetHubRococo, Rococo);
+impl_assets_helpers_for_parachain!(AssetHubRococo);
 impl_xcm_helpers_for_parachain!(AssetHubRococo);

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

@@ -14,17 +14,24 @@
 // limitations under the License.
 
 // Substrate
-use sp_core::storage::Storage;
+use frame_support::parameter_types;
+use sp_core::{sr25519, storage::Storage};
 
 // Cumulus
 use emulated_integration_tests_common::{
-	accounts, build_genesis_storage, collators, SAFE_XCM_VERSION,
+	accounts, build_genesis_storage, collators, get_account_id_from_seed,
+	PenpalSiblingSovereigAccount, PenpalTeleportableAssetLocation, RESERVABLE_ASSET_ID,
+	SAFE_XCM_VERSION,
 };
-use parachains_common::Balance;
+use parachains_common::{AccountId, Balance};
 
 pub const PARA_ID: u32 = 1000;
 pub const ED: Balance = testnet_parachains_constants::westend::currency::EXISTENTIAL_DEPOSIT;
 
+parameter_types! {
+	pub AssetHubWestendAssetOwner: AccountId = get_account_id_from_seed::<sr25519::Public>("Alice");
+}
+
 pub fn genesis() -> Storage {
 	let genesis_config = asset_hub_westend_runtime::RuntimeGenesisConfig {
 		system: asset_hub_westend_runtime::SystemConfig::default(),
@@ -56,6 +63,22 @@ pub fn genesis() -> Storage {
 			safe_xcm_version: Some(SAFE_XCM_VERSION),
 			..Default::default()
 		},
+		assets: asset_hub_westend_runtime::AssetsConfig {
+			assets: vec![(RESERVABLE_ASSET_ID, AssetHubWestendAssetOwner::get(), true, ED)],
+			..Default::default()
+		},
+		foreign_assets: asset_hub_westend_runtime::ForeignAssetsConfig {
+			assets: vec![
+				// Penpal's teleportable asset representation
+				(
+					PenpalTeleportableAssetLocation::get(),
+					PenpalSiblingSovereigAccount::get(),
+					true,
+					ED,
+				),
+			],
+			..Default::default()
+		},
 		..Default::default()
 	};
 

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

@@ -21,7 +21,7 @@ use frame_support::traits::OnInitialize;
 // Cumulus
 use emulated_integration_tests_common::{
 	impl_accounts_helpers_for_parachain, impl_assert_events_helpers_for_parachain,
-	impl_assets_helpers_for_parachain, impl_foreign_assets_helpers_for_parachain,
+	impl_assets_helpers_for_parachain, impl_assets_helpers_for_system_parachain,
 	impl_xcm_helpers_for_parachain, impls::Parachain, xcm_emulator::decl_test_parachains,
 };
 use westend_emulated_chain::Westend;
@@ -54,6 +54,6 @@ decl_test_parachains! {
 // AssetHubWestend implementation
 impl_accounts_helpers_for_parachain!(AssetHubWestend);
 impl_assert_events_helpers_for_parachain!(AssetHubWestend);
-impl_assets_helpers_for_parachain!(AssetHubWestend, Westend);
-impl_foreign_assets_helpers_for_parachain!(AssetHubWestend, Westend);
+impl_assets_helpers_for_system_parachain!(AssetHubWestend, Westend);
+impl_assets_helpers_for_parachain!(AssetHubWestend);
 impl_xcm_helpers_for_parachain!(AssetHubWestend);

cumulus/parachains/integration-tests/emulated/chains/parachains/testing/penpal/Cargo.toml

@@ -16,10 +16,11 @@ workspace = true
 sp-core = { path = "../../../../../../../../substrate/primitives/core", default-features = false }
 frame-support = { path = "../../../../../../../../substrate/frame/support", default-features = false }
 
+# Polkadot
+xcm = { package = "staging-xcm", path = "../../../../../../../../polkadot/xcm", default-features = false }
+
 # Cumulus
 parachains-common = { path = "../../../../../../../parachains/common" }
 cumulus-primitives-core = { path = "../../../../../../../primitives/core", default-features = false }
 emulated-integration-tests-common = { path = "../../../../common", default-features = false }
 penpal-runtime = { path = "../../../../../../runtimes/testing/penpal" }
-rococo-emulated-chain = { path = "../../../relays/rococo" }
-westend-emulated-chain = { path = "../../../relays/westend" }

cumulus/parachains/integration-tests/emulated/chains/parachains/testing/penpal/src/genesis.rs

@@ -14,19 +14,27 @@
 // limitations under the License.
 
 // Substrate
+use frame_support::parameter_types;
 use sp_core::{sr25519, storage::Storage};
 
+// Polkadot
+use xcm::v3::Location;
 // Cumulus
 use emulated_integration_tests_common::{
 	accounts, build_genesis_storage, collators, get_account_id_from_seed, SAFE_XCM_VERSION,
 };
-use parachains_common::Balance;
-
+use parachains_common::{AccountId, Balance};
+use penpal_runtime::xcm_config::{LocalReservableFromAssetHub, RelayLocation};
 // Penpal
 pub const PARA_ID_A: u32 = 2000;
 pub const PARA_ID_B: u32 = 2001;
 pub const ED: Balance = penpal_runtime::EXISTENTIAL_DEPOSIT;
 
+parameter_types! {
+	pub PenpalSudoAcccount: AccountId = get_account_id_from_seed::<sr25519::Public>("Alice");
+	pub PenpalAssetOwner: AccountId = PenpalSudoAcccount::get();
+}
+
 pub fn genesis(para_id: u32) -> Storage {
 	let genesis_config = penpal_runtime::RuntimeGenesisConfig {
 		system: penpal_runtime::SystemConfig::default(),
@@ -58,8 +66,35 @@ pub fn genesis(para_id: u32) -> Storage {
 			safe_xcm_version: Some(SAFE_XCM_VERSION),
 			..Default::default()
 		},
-		sudo: penpal_runtime::SudoConfig {
-			key: Some(get_account_id_from_seed::<sr25519::Public>("Alice")),
+		sudo: penpal_runtime::SudoConfig { key: Some(PenpalSudoAcccount::get()) },
+		assets: penpal_runtime::AssetsConfig {
+			assets: vec![(
+				penpal_runtime::xcm_config::TELEPORTABLE_ASSET_ID,
+				PenpalAssetOwner::get(),
+				false,
+				ED,
+			)],
+			..Default::default()
+		},
+		foreign_assets: penpal_runtime::ForeignAssetsConfig {
+			assets: vec![
+				// Relay Native asset representation
+				(
+					Location::try_from(RelayLocation::get()).expect("conversion works"),
+					PenpalAssetOwner::get(),
+					true,
+					ED,
+				),
+				// Sufficient AssetHub asset representation
+				(
+					Location::try_from(LocalReservableFromAssetHub::get())
+						.expect("conversion works"),
+					PenpalAssetOwner::get(),
+					true,
+					ED,
+				),
+			],
+			..Default::default()
 		},
 		..Default::default()
 	};

cumulus/parachains/integration-tests/emulated/chains/parachains/testing/penpal/src/lib.rs

@@ -14,10 +14,9 @@
 // limitations under the License.
 
 mod genesis;
-pub use genesis::{genesis, ED, PARA_ID_A, PARA_ID_B};
+pub use genesis::{genesis, PenpalAssetOwner, PenpalSudoAcccount, ED, PARA_ID_A, PARA_ID_B};
 pub use penpal_runtime::xcm_config::{
-	CustomizableAssetFromSystemAssetHub, LocalTeleportableToAssetHub,
-	LocalTeleportableToAssetHubV3, XcmConfig,
+	CustomizableAssetFromSystemAssetHub, LocalTeleportableToAssetHub, XcmConfig,
 };
 
 // Substrate
@@ -28,8 +27,6 @@ use emulated_integration_tests_common::{
 	impl_accounts_helpers_for_parachain, impl_assert_events_helpers_for_parachain,
 	impl_assets_helpers_for_parachain, impls::Parachain, xcm_emulator::decl_test_parachains,
 };
-use rococo_emulated_chain::Rococo;
-use westend_emulated_chain::Westend;
 
 // Penpal Parachain declaration
 decl_test_parachains! {
@@ -76,7 +73,7 @@ decl_test_parachains! {
 // Penpal implementation
 impl_accounts_helpers_for_parachain!(PenpalA);
 impl_accounts_helpers_for_parachain!(PenpalB);
-impl_assets_helpers_for_parachain!(PenpalA, Rococo);
-impl_assets_helpers_for_parachain!(PenpalB, Westend);
 impl_assert_events_helpers_for_parachain!(PenpalA);
 impl_assert_events_helpers_for_parachain!(PenpalB);
+impl_assets_helpers_for_parachain!(PenpalA);
+impl_assets_helpers_for_parachain!(PenpalB);

cumulus/parachains/integration-tests/emulated/common/Cargo.toml

@@ -27,6 +27,7 @@ pallet-message-queue = { path = "../../../../../substrate/frame/message-queue" }
 
 # Polkadot
 polkadot-primitives = { path = "../../../../../polkadot/primitives" }
+polkadot-parachain-primitives = { path = "../../../../../polkadot/parachain" }
 polkadot-runtime-parachains = { path = "../../../../../polkadot/runtime/parachains" }
 xcm = { package = "staging-xcm", path = "../../../../../polkadot/xcm" }
 pallet-xcm = { path = "../../../../../polkadot/xcm/pallet-xcm" }