Oneshot accounts

Add lighter accounts that can be consumed only once.

Je n'ai pas encore fait les tests unitaires car la config de mock est assez longue à faire. Mais les tests d'intégration sont là.

Est-ce que l'ordre des deposit_event importe ? Si non, le code des calls peut être un peu factorisé sans coût.

pallets/oneshot-account/src/lib.rs

@@ -23,6 +23,7 @@ use frame_support::traits::{
     Currency, ExistenceRequirement, Imbalance, IsSubType, WithdrawReasons,
 };
 use frame_system::pallet_prelude::*;
+use pallet_transaction_payment::OnChargeTransaction;
 use sp_runtime::traits::{DispatchInfoOf, PostDispatchInfoOf, Saturating, StaticLookup, Zero};
 
 #[frame_support::pallet]
@@ -46,6 +47,7 @@ pub mod pallet {
         type Currency: Currency<Self::AccountId>;
         /// The overarching event type.
         type Event: From<Event<Self>> + IsType<<Self as frame_system::Config>::Event>;
+        type InnerOnChargeTransaction: OnChargeTransaction<Self>;
     }
 
     // STORAGE //
@@ -329,7 +331,7 @@ pub mod pallet {
 impl<T: Config> pallet_transaction_payment::OnChargeTransaction<T> for Pallet<T>
 where
     T::Call: IsSubType<Call<T>>,
-    T::Currency:
+    /*T::Currency:
         Currency<
             T::AccountId,
             Balance = <T::OnChargeTransaction as pallet_transaction_payment::OnChargeTransaction<
@@ -343,12 +345,12 @@ where
     <T::Currency as Currency<T::AccountId>>::NegativeImbalance: Imbalance<
         <T::Currency as Currency<<T as frame_system::Config>::AccountId>>::Balance,
         Opposite = <T::Currency as Currency<T::AccountId>>::PositiveImbalance,
-    >,
-    /*T::OnChargeTransaction: pallet_transaction_payment::OnChargeTransaction<
+    >,*/
+    T::InnerOnChargeTransaction: pallet_transaction_payment::OnChargeTransaction<
         T,
         Balance = <T::Currency as Currency<T::AccountId>>::Balance,
         LiquidityInfo = Option<<T::Currency as Currency<T::AccountId>>::NegativeImbalance>,
-    >,*/
+    >,
 {
     type Balance = <T::Currency as Currency<T::AccountId>>::Balance;
     type LiquidityInfo = Option<<T::Currency as Currency<T::AccountId>>::NegativeImbalance>;
@@ -384,7 +386,7 @@ where
                 InvalidTransaction::Payment,
             ))
         } else {
-            T::OnChargeTransaction::withdraw_fee(who, call, dispatch_info, fee, tip)
+            T::InnerOnChargeTransaction::withdraw_fee(who, call, dispatch_info, fee, tip)
         }
     }
     fn correct_and_deposit_fee(
@@ -395,7 +397,7 @@ where
         tip: Self::Balance,
         already_withdrawn: Self::LiquidityInfo,
     ) -> Result<(), TransactionValidityError> {
-        T::OnChargeTransaction::correct_and_deposit_fee(
+        T::InnerOnChargeTransaction::correct_and_deposit_fee(
             who,
             dispatch_info,
             post_info,