use Happened trait for lifecycle callbacks instead

tokens/src/lib.rs

@@ -68,7 +68,7 @@ use orml_traits::{
 	arithmetic::{self, Signed},
 	currency::TransferAll,
 	BalanceStatus, GetByKey, LockIdentifier, MultiCurrency, MultiCurrencyExtended, MultiLockableCurrency,
-	MultiReservableCurrency, NamedMultiReservableCurrency, OnDust, OnNewTokenAccount, OnKilledTokenAccount,
+	MultiReservableCurrency, NamedMultiReservableCurrency, OnDust, Happened,
 };
 
 mod imbalances;
@@ -217,10 +217,10 @@ pub mod module {
 		type OnDust: OnDust<Self::AccountId, Self::CurrencyId, Self::Balance>;
 
 		/// Handler for when an account was created
-		type OnNewTokenAccount: OnNewTokenAccount<Self::AccountId, Self::CurrencyId>;
+		type OnNewTokenAccount: Happened<(Self::AccountId, Self::CurrencyId)>;
 
 		/// Handler for when an account was created
-		type OnKilledTokenAccount: OnKilledTokenAccount<Self::AccountId, Self::CurrencyId>;
+		type OnKilledTokenAccount: Happened<(Self::AccountId, Self::CurrencyId)>;
 
 		#[pallet::constant]
 		type MaxLocks: Get<u32>;
@@ -753,11 +753,11 @@ impl<T: Config> Pallet<T> {
 				// Ignore the result, because if it failed then there are remaining consumers,
 				// and the account storage in frame_system shouldn't be reaped.
 				let _ = frame_system::Pallet::<T>::dec_providers(who);
-				T::OnKilledTokenAccount::on_killed_account_for(&who, currency_id);
+				T::OnKilledTokenAccount::happened(&(who.clone(), currency_id));
 			} else if !existed && exists {
 				// if new, increase account provider
 				frame_system::Pallet::<T>::inc_providers(who);
-				T::OnNewTokenAccount::on_new_account_for(&who, currency_id);
+				T::OnNewTokenAccount::happened(&(who.clone(), currency_id));
 			}
 
 			if let Some(endowed) = maybe_endowed {

tokens/src/mock.rs

@@ -235,9 +235,9 @@ impl TrackCreatedAccounts {
 		CREATED.with(|accounts| { accounts.replace(vec![]); });
 	}
 }
-impl OnNewTokenAccount<AccountId, CurrencyId> for TrackCreatedAccounts {
-	fn on_new_account_for(who: &AccountId, currency: CurrencyId) {
-		CREATED.with(|accounts| { accounts.borrow_mut().push((who.clone(), currency)); });
+impl Happened<(AccountId, CurrencyId)> for TrackCreatedAccounts {
+	fn happened((who, currency): &(AccountId, CurrencyId)) {
+		CREATED.with(|accounts| { accounts.borrow_mut().push((who.clone(), *currency)); });
 	}
 }
 
@@ -251,9 +251,9 @@ impl TrackKilledAccounts {
 		KILLED.with(|accounts| { accounts.replace(vec![]); });
 	}
 }
-impl OnKilledTokenAccount<AccountId, CurrencyId> for TrackKilledAccounts {
-	fn on_killed_account_for(who: &AccountId, currency: CurrencyId) {
-		KILLED.with(|accounts| { accounts.borrow_mut().push((who.clone(), currency)); });
+impl Happened<(AccountId, CurrencyId)> for TrackKilledAccounts {
+	fn happened((who, currency): &(AccountId, CurrencyId)) {
+		KILLED.with(|accounts| { accounts.borrow_mut().push((who.clone(), *currency)); });
 	}
 }
 

traits/src/currency.rs

@@ -643,24 +643,6 @@ impl<AccountId, CurrencyId, Balance> OnDust<AccountId, CurrencyId, Balance> for
 	fn on_dust(_: &AccountId, _: CurrencyId, _: Balance) {}
 }
 
-/// Handler for a newly created account
-pub trait OnNewTokenAccount<AccountId, CurrencyId> {
-	fn on_new_account_for(who: &AccountId, currency_id: CurrencyId);
-}
-
-impl<AccountId, CurrencyId> OnNewTokenAccount<AccountId, CurrencyId> for () {
-	fn on_new_account_for(_: &AccountId, _: CurrencyId) {}
-}
-
-/// Handler for an account that was removed
-pub trait OnKilledTokenAccount<AccountId, CurrencyId> {
-	fn on_killed_account_for(who: &AccountId, currency_id: CurrencyId);
-}
-
-impl<AccountId, CurrencyId> OnKilledTokenAccount<AccountId, CurrencyId> for () {
-	fn on_killed_account_for(_: &AccountId, _: CurrencyId) {}
-}
-
 pub trait TransferAll<AccountId> {
 	fn transfer_all(source: &AccountId, dest: &AccountId) -> DispatchResult;
 }

traits/src/lib.rs

@@ -16,7 +16,7 @@ pub use auction::{Auction, AuctionHandler, AuctionInfo, OnNewBidResult};
 pub use currency::{
 	BalanceStatus, BasicCurrency, BasicCurrencyExtended, BasicLockableCurrency, BasicReservableCurrency,
 	LockIdentifier, MultiCurrency, MultiCurrencyExtended, MultiLockableCurrency, MultiReservableCurrency,
-	NamedBasicReservableCurrency, NamedMultiReservableCurrency, OnDust, OnNewTokenAccount, OnKilledTokenAccount,
+	NamedBasicReservableCurrency, NamedMultiReservableCurrency, OnDust,
 };
 pub use data_provider::{DataFeeder, DataProvider, DataProviderExtended};
 pub use get_by_key::GetByKey;