Rename to DenyExportMessageFrom with comments

polkadot/xcm/xcm-builder/src/barriers.rs

@@ -507,13 +507,15 @@ impl ShouldNotExecute for DenyReserveTransferToRelayChain {
 	}
 }
 
-// See https://github.com/paritytech/polkadot-sdk/pull/6838
-pub struct DenyFirstExportMessageFrom<FromOrigin, ToGlobalConsensus>(
+/// Deny execution if the message contains instruction `ExportMessage` with
+/// a. origin is contained in `FromOrigin` (i.e.`FromOrigin::Contains(origin)`)
+/// b. network is contained in `ToGlobalConsensus`, (i.e. `ToGlobalConsensus::contains(network)`)
+pub struct DenyExportMessageFrom<FromOrigin, ToGlobalConsensus>(
 	PhantomData<(FromOrigin, ToGlobalConsensus)>,
 );
 
 impl<FromOrigin, ToGlobalConsensus> ShouldNotExecute
-	for DenyFirstExportMessageFrom<FromOrigin, ToGlobalConsensus>
+	for DenyExportMessageFrom<FromOrigin, ToGlobalConsensus>
 where
 	FromOrigin: Contains<Location>,
 	ToGlobalConsensus: Contains<NetworkId>,

polkadot/xcm/xcm-builder/src/lib.rs

@@ -42,9 +42,9 @@ mod barriers;
 pub use barriers::{
 	AllowExplicitUnpaidExecutionFrom, AllowHrmpNotificationsFromRelayChain,
 	AllowKnownQueryResponses, AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom,
-	AllowUnpaidExecutionFrom, DenyFirstExportMessageFrom, DenyReserveTransferToRelayChain,
-	DenyThenTry, IsChildSystemParachain, IsParentsOnly, IsSiblingSystemParachain,
-	RespectSuspension, TakeWeightCredit, TrailingSetTopicAsId, WithComputedOrigin,
+	AllowUnpaidExecutionFrom, DenyExportMessageFrom, DenyReserveTransferToRelayChain, DenyThenTry,
+	IsChildSystemParachain, IsParentsOnly, IsSiblingSystemParachain, RespectSuspension,
+	TakeWeightCredit, TrailingSetTopicAsId, WithComputedOrigin,
 };
 
 mod controller;

polkadot/xcm/xcm-builder/src/tests/barriers.rs

@@ -546,7 +546,7 @@ parameter_types! {
 #[test]
 fn deny_reserver_transfer_to_relaychain_should_work() {
 	pub type Barrier = DenyThenTry<
-		(DenyReserveTransferToRelayChain, DenyFirstExportMessageFrom<Everything, Everything>),
+		(DenyReserveTransferToRelayChain, DenyExportMessageFrom<Everything, Everything>),
 		TakeWeightCredit,
 	>;
 
@@ -571,10 +571,7 @@ fn deny_export_message_from_source_other_than_asset_hub_should_work() {
 	pub type Barrier = DenyThenTry<
 		(
 			DenyReserveTransferToRelayChain,
-			DenyFirstExportMessageFrom<
-				EverythingBut<Equals<AssetHubLocation>>,
-				Equals<EthereumNetwork>,
-			>,
+			DenyExportMessageFrom<EverythingBut<Equals<AssetHubLocation>>, Equals<EthereumNetwork>>,
 		),
 		TakeWeightCredit,
 	>;
@@ -603,10 +600,7 @@ fn allow_export_message_from_asset_hub_should_work() {
 	pub type Barrier = DenyThenTry<
 		(
 			DenyReserveTransferToRelayChain,
-			DenyFirstExportMessageFrom<
-				EverythingBut<Equals<AssetHubLocation>>,
-				Equals<EthereumNetwork>,
-			>,
+			DenyExportMessageFrom<EverythingBut<Equals<AssetHubLocation>>, Equals<EthereumNetwork>>,
 		),
 		TakeWeightCredit,
 	>;
@@ -635,10 +629,7 @@ fn allow_export_message_from_source_other_than_asset_hub_if_destination_other_th
 	pub type Barrier = DenyThenTry<
 		(
 			DenyReserveTransferToRelayChain,
-			DenyFirstExportMessageFrom<
-				EverythingBut<Equals<AssetHubLocation>>,
-				Equals<EthereumNetwork>,
-			>,
+			DenyExportMessageFrom<EverythingBut<Equals<AssetHubLocation>>, Equals<EthereumNetwork>>,
 		),
 		TakeWeightCredit,
 	>;