Statemint runtimes to accept sufficient assets as xcm fee payment (#1278)

* point to my branch

* girazoki-add-TakeFirstAssetTrader-to-utility

* Commit lock

* point at custom branch

* add new trader to statemine runtimes

* compiles

* Back to master

* Update last tomls

* Imports up

* remove non-needing imports

* FMT

* log messages properly

* Use TakeRevenue instead of HandleCredit

* Introduce xcm fee handler

* check total supply in tests

* FMT

* fix test

* Start decoupling balance calculation into different traits

* Make traits a bit more generic

* PR suggestions

* add import

* import well

* Place xcmfeesassethandler into parachains common

* fix tests

* config parameters

* Min amount to fee receiver

* Make minimum amount for block author to be at least the ED

* Doc in AssetFeeAsExistentialDepositMultiplier

* saturating sub

* make sure we dont enter twice

* FMT

* fmt again

* adapt tests

* Add doc and struct for weight refund

* Doc

* More doc

* PR suggestions

* store all info related to asset payment as multiasset

* return AssetNotFound instead of TooExpensive

* Use asset transactor to deposit fee

* uninstall from statemint

* R for RUntime and CON for BalanceConverter

* Rework logic to avoid unnecesary match and error

* Rework ED check, also in case of refund

* rework typo

* In case refund makes drop below ED, just refund the difference

* fix test westmint

* clone id

* move test imports to preamble

* move test imports to preamble

* test-utils with builderS

* lock file updated

* remove unused imports

Co-authored-by: Stephen Shelton <steve@brewcraft.org>
Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: joepetrowski <joe@parity.io>

cumulus/parachains/runtimes/assets/statemine/src/xcm_config.rs

@@ -14,7 +14,7 @@
 // limitations under the License.
 
 use super::{
-	AccountId, AssetId, Assets, Balance, Balances, Call, Event, Origin, ParachainInfo,
+	AccountId, AssetId, Assets, Authorship, Balance, Balances, Call, Event, Origin, ParachainInfo,
 	ParachainSystem, PolkadotXcm, Runtime, WeightToFee, XcmpQueue,
 };
 use frame_support::{
@@ -25,9 +25,12 @@ use frame_support::{
 use pallet_xcm::XcmPassthrough;
 use parachains_common::{
 	impls::ToStakingPot,
-	xcm_config::{DenyReserveTransferToRelayChain, DenyThenTry},
+	xcm_config::{
+		AssetFeeAsExistentialDepositMultiplier, DenyReserveTransferToRelayChain, DenyThenTry,
+	},
 };
 use polkadot_parachain::primitives::Sibling;
+use sp_runtime::traits::ConvertInto;
 use xcm::latest::prelude::*;
 use xcm_builder::{
 	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
@@ -129,6 +132,7 @@ parameter_types! {
 	// One XCM operation is 1_000_000_000 weight - almost certainly a conservative estimate.
 	pub UnitWeightCost: Weight = 1_000_000_000;
 	pub const MaxInstructions: u32 = 100;
+	pub XcmAssetFeesReceiver: Option<AccountId> = Authorship::author();
 }
 
 match_types! {
@@ -170,8 +174,29 @@ impl xcm_executor::Config for XcmConfig {
 	type LocationInverter = LocationInverter<Ancestry>;
 	type Barrier = Barrier;
 	type Weigher = FixedWeightBounds<UnitWeightCost, Call, MaxInstructions>;
-	type Trader =
-		UsingComponents<WeightToFee, KsmLocation, AccountId, Balances, ToStakingPot<Runtime>>;
+	type Trader = (
+		UsingComponents<WeightToFee, KsmLocation, AccountId, Balances, ToStakingPot<Runtime>>,
+		cumulus_primitives_utility::TakeFirstAssetTrader<
+			AccountId,
+			AssetFeeAsExistentialDepositMultiplier<
+				Runtime,
+				WeightToFee,
+				pallet_assets::BalanceToAssetBalance<Balances, Runtime, ConvertInto>,
+			>,
+			ConvertedConcreteAssetId<
+				AssetId,
+				Balance,
+				AsPrefixedGeneralIndex<AssetsPalletLocation, AssetId, JustTry>,
+				JustTry,
+			>,
+			Assets,
+			cumulus_primitives_utility::XcmFeesTo32ByteAccount<
+				FungiblesTransactor,
+				AccountId,
+				XcmAssetFeesReceiver,
+			>,
+		>,
+	);
 	type ResponseHandler = PolkadotXcm;
 	type AssetTrap = PolkadotXcm;
 	type AssetClaims = PolkadotXcm;