pallet_assets : Remove event for no_op (#11023)

* remove no_op event

* ensure no transferred event emitted

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/frame/assets/src/functions.rs

@@ -529,14 +529,8 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 		maybe_need_admin: Option<T::AccountId>,
 		f: TransferFlags,
 	) -> Result<(T::Balance, Option<DeadConsequence>), DispatchError> {
-		// Early exist if no-op.
+		// Early exit if no-op.
 		if amount.is_zero() {
-			Self::deposit_event(Event::Transferred {
-				asset_id: id,
-				from: source.clone(),
-				to: dest.clone(),
-				amount,
-			});
 			return Ok((amount, None))
 		}
 

substrate/frame/assets/src/tests.rs

@@ -620,12 +620,8 @@ fn transferring_less_than_one_unit_is_fine() {
 		assert_ok!(Assets::mint(Origin::signed(1), 0, 1, 100));
 		assert_eq!(Assets::balance(0, 1), 100);
 		assert_ok!(Assets::transfer(Origin::signed(1), 0, 2, 0));
-		System::assert_last_event(mock::Event::Assets(crate::Event::Transferred {
-			asset_id: 0,
-			from: 1,
-			to: 2,
-			amount: 0,
-		}));
+		// `ForceCreated` and `Issued` but no `Transferred` event.
+		assert_eq!(System::events().len(), 2);
 	});
 }