revert dont reward relayer

bridges/snowbridge/parachain/pallets/inbound-queue/src/lib.rs

@@ -41,15 +41,14 @@ use envelope::Envelope;
 use frame_support::{
 	traits::{
 		fungible::{Inspect, Mutate},
-		tokens::{Fortitude, Preservation},
+		tokens::Preservation,
 	},
 	weights::WeightToFee,
 	PalletError,
 };
 use frame_system::ensure_signed;
 use scale_info::TypeInfo;
 use sp_core::{H160, H256};
-use sp_runtime::traits::Zero;
 use sp_std::{convert::TryFrom, vec};
 use xcm::prelude::{
 	send_xcm, Instruction::SetTopic, Junction::*, Location, SendError as XcmpSendError, SendXcm,
@@ -262,19 +261,11 @@ pub mod pallet {
 				}
 			})?;
 
-			// Reward relayer from the sovereign account of the destination parachain, only if funds
-			// are available
+			// Reward relayer from the sovereign account of the destination parachain
+			// Expected to fail if sovereign account has no funds
 			let sovereign_account = sibling_sovereign_account::<T>(channel.para_id);
 			let delivery_cost = Self::calculate_delivery_cost(message.encode().len() as u32);
-			let amount = T::Token::reducible_balance(
-				&sovereign_account,
-				Preservation::Preserve,
-				Fortitude::Polite,
-			)
-			.min(delivery_cost);
-			if !amount.is_zero() {
-				T::Token::transfer(&sovereign_account, &who, amount, Preservation::Preserve)?;
-			}
+			T::Token::transfer(&sovereign_account, &who, delivery_cost, Preservation::Preserve)?;
 
 			// Decode message into XCM
 			let (xcm, fee) =

bridges/snowbridge/parachain/pallets/inbound-queue/src/mock.rs

@@ -3,8 +3,8 @@
 use super::*;
 
 use frame_support::{
-	derive_impl, parameter_types,
-	traits::{ConstU32, Everything},
+	parameter_types,
+	traits::{ConstU128, ConstU32, Everything},
 	weights::IdentityFee,
 };
 use hex_literal::hex;
@@ -76,18 +76,14 @@ impl frame_system::Config for Test {
 	type Block = Block;
 }
 
-parameter_types! {
-	pub const ExistentialDeposit: u128 = 1;
-}
-
 impl pallet_balances::Config for Test {
 	type MaxLocks = ();
 	type MaxReserves = ();
 	type ReserveIdentifier = [u8; 8];
 	type Balance = Balance;
 	type RuntimeEvent = RuntimeEvent;
 	type DustRemoval = ();
-	type ExistentialDeposit = ExistentialDeposit;
+	type ExistentialDeposit = ConstU128<1>;
 	type AccountStore = System;
 	type WeightInfo = ();
 	type FreezeIdentifier = ();

bridges/snowbridge/parachain/pallets/inbound-queue/src/test.rs

@@ -6,7 +6,7 @@ use frame_support::{assert_noop, assert_ok};
 use hex_literal::hex;
 use snowbridge_core::{inbound::Proof, ChannelId};
 use sp_keyring::AccountKeyring as Keyring;
-use sp_runtime::DispatchError;
+use sp_runtime::{DispatchError, TokenError};
 use sp_std::convert::From;
 
 use crate::{Error, Event as InboundQueueEvent};
@@ -146,25 +146,28 @@ fn test_submit_with_invalid_nonce() {
 }
 
 #[test]
-fn test_submit_no_funds_to_reward_relayers_just_ignore() {
+fn test_submit_no_funds_to_reward_relayers() {
 	new_tester().execute_with(|| {
 		let relayer: AccountId = Keyring::Bob.into();
 		let origin = RuntimeOrigin::signed(relayer);
 
-		// Reset balance of sovereign_account to zero first
+		// Reset balance of sovereign_account to zero so to trigger the FundsUnavailable error
 		let sovereign_account = sibling_sovereign_account::<Test>(ASSET_HUB_PARAID.into());
 		Balances::set_balance(&sovereign_account, 0);
 
 		// Submit message
 		let message = Message {
 			event_log: mock_event_log(),
 			proof: Proof {
-				receipt_proof: Default::default(),
-				execution_proof: mock_execution_proof(),
+				block_hash: Default::default(),
+				tx_index: Default::default(),
+				data: Default::default(),
 			},
 		};
-		// Check submit successfully in case no funds available
-		assert_ok!(InboundQueue::submit(origin.clone(), message.clone()));
+		assert_noop!(
+			InboundQueue::submit(origin.clone(), message.clone()),
+			TokenError::FundsUnavailable
+		);
 	});
 }
 
@@ -202,44 +205,3 @@ fn test_set_operating_mode_root_only() {
 		);
 	});
 }
-
-#[test]
-fn test_submit_no_funds_to_reward_relayers_and_ed_preserved() {
-	new_tester().execute_with(|| {
-		let relayer: AccountId = Keyring::Bob.into();
-		let origin = RuntimeOrigin::signed(relayer);
-
-		// Reset balance of sovereign account to (ED+1) first
-		let sovereign_account = sibling_sovereign_account::<Test>(ASSET_HUB_PARAID.into());
-		Balances::set_balance(&sovereign_account, ExistentialDeposit::get() + 1);
-
-		// Submit message successfully
-		let message = Message {
-			event_log: mock_event_log(),
-			proof: Proof {
-				receipt_proof: Default::default(),
-				execution_proof: mock_execution_proof(),
-			},
-		};
-		assert_ok!(InboundQueue::submit(origin.clone(), message.clone()));
-
-		// Check balance of sovereign account to ED
-		let amount = Balances::balance(&sovereign_account);
-		assert_eq!(amount, ExistentialDeposit::get());
-
-		// Submit another message with nonce set as 2
-		let mut event_log = mock_event_log();
-		event_log.data[31] = 2;
-		let message = Message {
-			event_log,
-			proof: Proof {
-				receipt_proof: Default::default(),
-				execution_proof: mock_execution_proof(),
-			},
-		};
-		assert_ok!(InboundQueue::submit(origin.clone(), message.clone()));
-		// Check balance of sovereign account as ED does not change
-		let amount = Balances::balance(&sovereign_account);
-		assert_eq!(amount, ExistentialDeposit::get());
-	});
-}

cumulus/parachains/integration-tests/emulated/tests/bridges/bridge-hub-rococo/src/tests/snowbridge.rs

@@ -30,7 +30,7 @@ use snowbridge_router_primitives::inbound::{
 	Command, GlobalConsensusEthereumConvertsFor, MessageV1, VersionedMessage,
 };
 use sp_core::H256;
-use sp_runtime::{DispatchError::Token, TokenError::FundsUnavailable};
+use sp_runtime::{ArithmeticError::Underflow, DispatchError::Arithmetic};
 use testnet_parachains_constants::rococo::snowbridge::EthereumNetwork;
 
 const INITIAL_FUND: u128 = 5_000_000_000 * ROCOCO_ED;
@@ -515,7 +515,7 @@ fn send_token_from_ethereum_to_asset_hub_fail_for_insufficient_fund() {
 	BridgeHubRococo::fund_para_sovereign(AssetHubRococo::para_id().into(), 1_000);
 
 	BridgeHubRococo::execute_with(|| {
-		assert_err!(send_inbound_message(make_register_token_message()), Token(FundsUnavailable));
+		assert_err!(send_inbound_message(make_register_token_message()), Arithmetic(Underflow));
 	});
 }