Fix: deal with double transact msg (#1965)

* Update lib.rs

* Update lib.rs

* fix ci

Author: mclyk

pallets/xcm-helper/src/lib.rs

@@ -273,8 +273,19 @@ impl<T: Config> Pallet<T> {
             query_id,
             max_weight,
         });
-        // Prepend SetAppendix(Xcm(vec![ReportError])) wont be able to pass barrier check
-        // so we need to insert it after Withdraw, BuyExecution
+        // Before insertion is:
+        // 0: WithdrawAsset
+        // 1: BuyExecution
+        // 2: Transact
+        // 3: RefundSurplus
+        // 4: DepositAsset
+        // After insertion is:
+        // 0: WithdrawAsset
+        // 1: BuyExecution
+        // 2: Transact
+        // 3: ReportError
+        // 4: RefundSurplus
+        // 5: DepositAsset
         message.0.insert(3, report_error);
         Ok(query_id)
     }
@@ -288,9 +299,25 @@ impl<T: Config> Pallet<T> {
 
     // Since xcm v3 doesn't support utility.batch_all
     // instead, here append one more transact msg
-    //
-    // NOTE: index here is 3,
-    // must append before 'report_outcome_notify' that index is 2
+
+    // A new bug occurred due to XCM version incompatible,
+    // here is a temp solutin which is ugly:
+    // ***`append_transact` MUST invoke after `report_outcome_notify`***
+    // Before insertion is:
+    // 0: WithdrawAsset
+    // 1: BuyExecution
+    // 2: Transact
+    // 3: ReportError
+    // 4: RefundSurplus
+    // 5: DepositAsset
+    // After insertion is:
+    // 0: WithdrawAsset
+    // 1: BuyExecution
+    // 2: Transact
+    // 3: Transact
+    // 4: ReportError
+    // 5: RefundSurplus
+    // 6: DepositAsset
     pub fn append_transact(message: &mut Xcm<()>, call: DoubleEncoded<()>, weight: Weight) {
         message.0.insert(
             3,
@@ -516,6 +543,13 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
                 xcm_weight_fee_misc.fee,
             )?;
 
+            let query_id = Self::report_outcome_notify(
+                &mut msg,
+                MultiLocation::parent(),
+                notify,
+                T::NotifyTimeout::get(),
+            )?;
+
             let call = RelaychainCall::<T>::Proxy(Box::new(ProxyCall::Proxy(ProxyProxyCall {
                 real,
                 force_proxy_type: None,
@@ -529,13 +563,6 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
             })));
             Self::append_transact(&mut msg, call.encode().into(), xcm_weight_fee_misc.weight);
 
-            let query_id = Self::report_outcome_notify(
-                &mut msg,
-                MultiLocation::parent(),
-                notify,
-                T::NotifyTimeout::get(),
-            )?;
-
             if let Err(_e) = send_xcm::<T::XcmSender>(MultiLocation::parent(), msg) {
                 return Err(Error::<T>::SendFailure.into());
             }
@@ -566,6 +593,14 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
                 Self::refund_location(),
                 xcm_weight_fee_misc.fee,
             )?;
+
+            let query_id = Self::report_outcome_notify(
+                &mut msg,
+                MultiLocation::parent(),
+                notify,
+                T::NotifyTimeout::get(),
+            )?;
+
             let call = RelaychainCall::<T>::Utility(Box::new(UtilityCall::AsDerivative(
                 UtilityAsDerivativeCall {
                     index,
@@ -576,16 +611,8 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
                     })),
                 },
             )));
-
             Self::append_transact(&mut msg, call.encode().into(), xcm_weight_fee_misc.weight);
 
-            let query_id = Self::report_outcome_notify(
-                &mut msg,
-                MultiLocation::parent(),
-                notify,
-                T::NotifyTimeout::get(),
-            )?;
-
             if let Err(_err) = send_xcm::<T::XcmSender>(MultiLocation::parent(), msg) {
                 return Err(Error::<T>::SendFailure.into());
             }
@@ -616,6 +643,13 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
                 xcm_weight_fee_misc.fee,
             )?;
 
+            let query_id = Self::report_outcome_notify(
+                &mut msg,
+                MultiLocation::parent(),
+                notify,
+                T::NotifyTimeout::get(),
+            )?;
+
             let call = RelaychainCall::<T>::Utility(Box::new(UtilityCall::AsDerivative(
                 UtilityAsDerivativeCall {
                     index,
@@ -626,13 +660,6 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
             )));
             Self::append_transact(&mut msg, call.encode().into(), xcm_weight_fee_misc.weight);
 
-            let query_id = Self::report_outcome_notify(
-                &mut msg,
-                MultiLocation::parent(),
-                notify,
-                T::NotifyTimeout::get(),
-            )?;
-
             if let Err(_err) = send_xcm::<T::XcmSender>(MultiLocation::parent(), msg) {
                 return Err(Error::<T>::SendFailure.into());
             }
@@ -741,6 +768,13 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
                 xcm_weight_fee_misc.fee,
             )?;
 
+            let query_id = Self::report_outcome_notify(
+                &mut msg,
+                MultiLocation::parent(),
+                notify,
+                T::NotifyTimeout::get(),
+            )?;
+
             let call = RelaychainCall::Utility(Box::new(UtilityCall::AsDerivative(
                 UtilityAsDerivativeCall {
                     index,
@@ -754,13 +788,6 @@ impl<T: Config> XcmHelper<T, BalanceOf<T>, AccountIdOf<T>> for Pallet<T> {
             )));
             Self::append_transact(&mut msg, call.encode().into(), xcm_weight_fee_misc.weight);
 
-            let query_id = Self::report_outcome_notify(
-                &mut msg,
-                MultiLocation::parent(),
-                notify,
-                T::NotifyTimeout::get(),
-            )?;
-
             if let Err(_err) = send_xcm::<T::XcmSender>(MultiLocation::parent(), msg) {
                 return Err(Error::<T>::SendFailure.into());
             }