Add deposit/withdraw events to EVM module (#5440)

* Add deposit/withdraw events

* Remove balances trait

substrate/frame/evm/src/backend.rs

@@ -172,7 +172,7 @@ impl<'vicinity, T: Trait> ApplyBackend for Backend<'vicinity, T> {
 		}
 
 		for log in logs {
-			Module::<T>::deposit_event(Event::Log(Log {
+			Module::<T>::deposit_event(Event::<T>::Log(Log {
 				address: log.address,
 				topics: log.topics,
 				data: log.data,

substrate/frame/evm/src/lib.rs

@@ -127,7 +127,7 @@ pub trait Trait: frame_system::Trait + pallet_timestamp::Trait {
 	/// Currency type for deposit and withdraw.
 	type Currency: Currency<Self::AccountId>;
 	/// The overarching event type.
-	type Event: From<Event> + Into<<Self as frame_system::Trait>::Event>;
+	type Event: From<Event<Self>> + Into<<Self as frame_system::Trait>::Event>;
 	/// Precompiles associated with this EVM engine.
 	type Precompiles: Precompiles;
 
@@ -147,11 +147,17 @@ decl_storage! {
 
 decl_event! {
 	/// EVM events
-	pub enum Event {
+	pub enum Event<T> where
+		<T as frame_system::Trait>::AccountId,
+	{
 		/// Ethereum events from contracts.
 		Log(Log),
 		/// A contract has been created at given address.
 		Created(H160),
+		/// A deposit has been made at a given address.
+		BalanceDeposit(AccountId, H160, U256),
+		/// A withdrawal has been made from a given address.
+		BalanceWithdraw(AccountId, H160, U256),
 	}
 }
 
@@ -202,6 +208,7 @@ decl_module! {
 			Accounts::mutate(&address, |account| {
 				account.balance += bvalue;
 			});
+			Module::<T>::deposit_event(Event::<T>::BalanceDeposit(sender, address, bvalue));
 		}
 
 		/// Withdraw balance from EVM into currency/balances module.
@@ -225,6 +232,7 @@ decl_module! {
 			Accounts::insert(&address, account);
 
 			T::Currency::resolve_creating(&sender, imbalance);
+			Module::<T>::deposit_event(Event::<T>::BalanceWithdraw(sender, address, bvalue));
 		}
 
 		/// Issue an EVM call operation. This is similar to a message call transaction in Ethereum.
@@ -289,7 +297,7 @@ decl_module! {
 				},
 			)?;
 
-			Module::<T>::deposit_event(Event::Created(create_address));
+			Module::<T>::deposit_event(Event::<T>::Created(create_address));
 			Ok(())
 		}
 
@@ -327,7 +335,7 @@ decl_module! {
 				},
 			)?;
 
-			Module::<T>::deposit_event(Event::Created(create_address));
+			Module::<T>::deposit_event(Event::<T>::Created(create_address));
 			Ok(())
 		}
 	}