[pallet-revive] Add Pallet::set_evm_balance

prdoc/pr_9617.prdoc

@@ -0,0 +1,9 @@
+title: '[pallet-revive] Add setting evm balance'
+doc:
+- audience: Runtime User
+  description: |-
+    Adds a balance setter in EVM for pallet-revive.
+
+crates:
+- name: pallet-revive
+  bump: minor

substrate/frame/revive/src/lib.rs

@@ -1539,11 +1539,32 @@ where
 	}
 
 	/// Get the balance with EVM decimals of the given `address`.
+	///
+	/// Returns the spendable balance excluding the existential deposit.
 	pub fn evm_balance(address: &H160) -> U256 {
 		let balance = AccountInfo::<T>::balance((*address).into());
 		Self::convert_native_to_evm(balance)
 	}
 
+	/// Set the EVM balance of an account.
+	///
+	/// The account's total balance becomes the EVM value plus the existential deposit,
+	/// consistent with `evm_balance` which returns the spendable balance excluding the existential
+	/// deposit.
+	pub fn set_evm_balance(address: &H160, evm_value: U256) -> Result<(), Error<T>> {
+		let ed = T::Currency::minimum_balance();
+		let balance_with_dust = BalanceWithDust::<BalanceOf<T>>::from_value::<T>(evm_value)
+			.map_err(|_| <Error<T>>::BalanceConversionFailed)?;
+		let (value, dust) = balance_with_dust.deconstruct();
+		let account_id = T::AddressMapper::to_account_id(&address);
+		T::Currency::set_balance(&account_id, ed.saturating_add(value));
+		AccountInfoOf::<T>::mutate(address, |account| {
+			account.as_mut().map(|a| a.dust = dust);
+		});
+
+		Ok(())
+	}
+
 	/// Get the nonce for the given `address`.
 	pub fn evm_nonce(address: &H160) -> u32
 	where

substrate/frame/revive/src/tests/pvm.rs

@@ -193,6 +193,22 @@ fn eth_call_transfer_with_dust_works() {
 	});
 }
 
+#[test]
+fn set_evm_balance_works() {
+	let (binary, _) = compile_module("dummy").unwrap();
+	ExtBuilder::default().existential_deposit(200).build().execute_with(|| {
+		let _ = <Test as Config>::Currency::set_balance(&ALICE, 1_000_000);
+		let Contract { addr, .. } =
+			builder::bare_instantiate(Code::Upload(binary)).build_and_unwrap_contract();
+		let native_with_dust = BalanceWithDust::new_unchecked::<Test>(100, 10);
+		let evm_value = Pallet::<Test>::convert_native_to_evm(native_with_dust);
+
+		assert_ok!(Pallet::<Test>::set_evm_balance(&addr, evm_value));
+
+		assert_eq!(Pallet::<Test>::evm_balance(&addr), evm_value);
+	});
+}
+
 #[test]
 fn contract_call_transfer_with_dust_works() {
 	let (binary_caller, _code_hash_caller) = compile_module("call_with_value").unwrap();