refactor: Improve weight-to-gas conversion and simplify nonce validation

- Use SignedGas::from_weight_fee().to_ethereum_gas() for proper weight-to-gas
  conversion that accounts for both ref_time and proof_size
- Simplify nonce validation in eip7702.rs using try_into() instead of
  separate bounds check
- Compare nonces as u64 directly instead of converting back and forth with U256

Author: pgherveou

substrate/frame/revive/src/evm/eip7702.rs

@@ -103,17 +103,18 @@ pub(crate) fn validate_authorization<T: Config>(
 		return None;
 	}
 
-	// Validate nonce is within bounds
-	if auth.nonce >= U256::from(u64::MAX) {
-		log::debug!(
-			target: crate::LOG_TARGET,
-			"Authorization nonce too large: {:?}",
-			auth.nonce
-		);
-		return None;
-	}
+	let expected_nonce: u64 = match auth.nonce.try_into() {
+		Ok(nonce) => nonce,
+		Err(_) => {
+			log::debug!(
+				target: crate::LOG_TARGET,
+				"Authorization nonce too large: {:?}",
+				auth.nonce
+			);
+			return None;
+		},
+	};
 
-	// Recover authority address from signature
 	let authority = match recover_authority(auth) {
 		Ok(addr) => addr,
 		Err(_) => {
@@ -122,16 +123,14 @@ pub(crate) fn validate_authorization<T: Config>(
 		},
 	};
 
-	// Verify nonce matches and check if account exists
 	let account_id = T::AddressMapper::to_account_id(&authority);
 	let is_new_account = !frame_system::Account::<T>::contains_key(&account_id);
-	let current_nonce = frame_system::Pallet::<T>::account_nonce(&account_id);
-	let expected_nonce = auth.nonce;
+	let current_nonce: u64 = frame_system::Pallet::<T>::account_nonce(&account_id).saturated_into();
 
-	if U256::from(current_nonce.saturated_into::<u64>()) != expected_nonce {
+	if current_nonce != expected_nonce {
 		log::debug!(
 			target: crate::LOG_TARGET,
-			"Nonce mismatch for {authority:?}: expected {current_nonce:?}, got {expected_nonce:?}",
+			"Nonce mismatch for {authority:?}: expected {expected_nonce:?}, got {current_nonce:?}",
 		);
 		return None;
 	}

substrate/frame/revive/src/lib.rs

@@ -1401,11 +1401,13 @@ pub mod pallet {
 					&mut meter,
 				)?;
 
-				let consumed_weight = meter.consumed();
-				let gas_scale: u64 = T::GasScale::get().into();
-				let auth_gas = consumed_weight.ref_time().saturating_div(gas_scale);
+				let weight_fee = T::FeeInfo::weight_to_fee(&meter.consumed());
+				let auth_gas = metering::SignedGas::<T>::from_weight_fee(weight_fee)
+					.to_ethereum_gas()
+					.unwrap_or_default();
 
-				let adjusted_gas_limit = eth_gas_limit.saturating_sub(U256::from(auth_gas));
+				let adjusted_gas_limit =
+					eth_gas_limit.saturating_sub(U256::from(auth_gas.saturated_into::<u128>()));
 				let adjusted_weight_limit = meter.remaining();
 
 				(adjusted_gas_limit, adjusted_weight_limit)
@@ -1917,11 +1919,12 @@ impl<T: Config> Pallet<T> {
 					EthTransactError::Message(format!("Failed to process authorizations: {err:?}"))
 				})?;
 
-			let consumed_weight = meter.consumed();
-			let gas_scale: u64 = T::GasScale::get().into();
-			consumed_weight.ref_time().saturating_div(gas_scale)
+			let weight_fee = T::FeeInfo::weight_to_fee(&meter.consumed());
+			metering::SignedGas::<T>::from_weight_fee(weight_fee)
+				.to_ethereum_gas()
+				.unwrap_or_default()
 		} else {
-			0
+			Default::default()
 		};
 
 		let extract_error = |err| {
@@ -2076,8 +2079,7 @@ impl<T: Config> Pallet<T> {
 		if !rest.is_zero() {
 			eth_gas = eth_gas.saturating_add(1_u32.into());
 		}
-		// Add gas consumed by EIP-7702 authorization processing
-		eth_gas = eth_gas.saturating_add(U256::from(auth_gas_used));
+		eth_gas = eth_gas.saturating_add(U256::from(auth_gas_used.saturated_into::<u128>()));
 
 		log::debug!(target: LOG_TARGET, "\
 			dry_run_eth_transact finished: \