Remove BuyExecution::orders (#3640)

* Remove BuyExecution::orders

* Fixes

* Fixes

* Fixes

* Formatting

polkadot/xcm/pallet-xcm/src/lib.rs

@@ -190,7 +190,6 @@ pub mod pallet {
 							weight: 0,
 							debt: dest_weight,
 							halt_on_error: false,
-							orders: vec![],
 							instructions: vec![],
 						},
 						DepositAsset { assets: Wild(All), max_assets, beneficiary: *beneficiary },
@@ -259,7 +258,6 @@ pub mod pallet {
 						weight: 0,
 						debt: dest_weight, // covers this, `TransferReserveAsset` xcm, and `DepositAsset` order.
 						halt_on_error: false,
-						orders: vec![],
 						instructions: vec![],
 					},
 					DepositAsset { assets: Wild(All), max_assets, beneficiary: *beneficiary },

polkadot/xcm/pallet-xcm/src/mock.rs

@@ -198,7 +198,6 @@ pub(crate) fn buy_execution<C>(fees: impl Into<MultiAsset>, debt: Weight) -> Ord
 		weight: 0,
 		debt,
 		halt_on_error: false,
-		orders: vec![],
 		instructions: vec![],
 	}
 }

polkadot/xcm/src/v0/order.rs

@@ -194,10 +194,7 @@ impl<Call> TryFrom<Order1<Call>> for Order<Call> {
 			},
 			Order1::QueryHolding { query_id, dest, assets } =>
 				QueryHolding { query_id, dest: dest.try_into()?, assets: assets.try_into()? },
-			Order1::BuyExecution { fees, weight, debt, halt_on_error, orders, instructions } => {
-				if !orders.is_empty() {
-					return Err(())
-				}
+			Order1::BuyExecution { fees, weight, debt, halt_on_error, instructions } => {
 				let xcm = instructions
 					.into_iter()
 					.map(Xcm::<Call>::try_from)

polkadot/xcm/src/v1/order.rs

@@ -19,7 +19,7 @@
 use super::{
 	super::v0::Order as Order0, MultiAsset, MultiAssetFilter, MultiAssets, MultiLocation, Xcm,
 };
-use alloc::{vec, vec::Vec};
+use alloc::vec::Vec;
 use core::{
 	convert::{TryFrom, TryInto},
 	result,
@@ -140,8 +140,6 @@ pub enum Order<Call> {
 	///   any surrounding operations/orders.
 	/// - `halt_on_error`: If `true`, the execution of the `orders` and `operations` will halt on the first failure. If
 	///   `false`, then execution will continue regardless.
-	/// - `orders`: Orders to be executed with the existing Holding Register; execution of these orders happens PRIOR to
-	///   execution of the `operations`. The (shallow) weight for these must be paid for with the `weight` purchased.
 	/// - `instructions`: XCM instructions to be executed outside of the context of the current Holding Register;
 	///   execution of these instructions happens AFTER the execution of the `orders`. The (shallow) weight for these
 	///   must be paid for with the `weight` purchased.
@@ -152,7 +150,6 @@ pub enum Order<Call> {
 		weight: u64,
 		debt: u64,
 		halt_on_error: bool,
-		orders: Vec<Order<Call>>,
 		instructions: Vec<Xcm<Call>>,
 	},
 }
@@ -179,10 +176,9 @@ impl<Call> Order<Call> {
 			InitiateTeleport { assets, dest, effects } =>
 				InitiateTeleport { assets, dest, effects },
 			QueryHolding { query_id, dest, assets } => QueryHolding { query_id, dest, assets },
-			BuyExecution { fees, weight, debt, halt_on_error, orders, instructions } => {
-				let orders = orders.into_iter().map(Order::from).collect();
+			BuyExecution { fees, weight, debt, halt_on_error, instructions } => {
 				let instructions = instructions.into_iter().map(Xcm::from).collect();
-				BuyExecution { fees, weight, debt, halt_on_error, orders, instructions }
+				BuyExecution { fees, weight, debt, halt_on_error, instructions }
 			},
 		}
 	}
@@ -232,14 +228,7 @@ impl<Call> TryFrom<Order0<Call>> for Order<Call> {
 			Order0::BuyExecution { fees, weight, debt, halt_on_error, xcm } => {
 				let instructions =
 					xcm.into_iter().map(Xcm::<Call>::try_from).collect::<result::Result<_, _>>()?;
-				BuyExecution {
-					fees: fees.try_into()?,
-					weight,
-					debt,
-					halt_on_error,
-					orders: vec![],
-					instructions,
-				}
+				BuyExecution { fees: fees.try_into()?, weight, debt, halt_on_error, instructions }
 			},
 		})
 	}

polkadot/xcm/xcm-builder/src/tests.rs

@@ -51,7 +51,6 @@ fn weigher_should_work() {
 				weight: 0,
 				debt: 30,
 				halt_on_error: true,
-				orders: vec![],
 				instructions: vec![],
 			},
 			Order::DepositAsset { assets: All.into(), max_assets: 1, beneficiary: Here.into() },
@@ -139,7 +138,6 @@ fn allow_paid_should_work() {
 				weight: 0,
 				debt: 20,
 				halt_on_error: true,
-				orders: vec![],
 				instructions: vec![],
 			},
 			Order::DepositAsset { assets: All.into(), max_assets: 1, beneficiary: Here.into() },
@@ -164,7 +162,6 @@ fn allow_paid_should_work() {
 				weight: 0,
 				debt: 30,
 				halt_on_error: true,
-				orders: vec![],
 				instructions: vec![],
 			},
 			Order::DepositAsset { assets: All.into(), max_assets: 1, beneficiary: Here.into() },
@@ -206,7 +203,6 @@ fn paying_reserve_deposit_should_work() {
 				weight: 0,
 				debt: 30,
 				halt_on_error: true,
-				orders: vec![],
 				instructions: vec![],
 			},
 			Order::<TestCall>::DepositAsset {
@@ -347,7 +343,6 @@ fn paid_transacting_should_refund_payment_for_unused_weight() {
 				weight: 70,
 				debt: 30,
 				halt_on_error: true,
-				orders: vec![],
 				instructions: vec![Xcm::<TestCall>::Transact {
 					origin_type: OriginKind::Native,
 					require_weight_at_most: 60,

polkadot/xcm/xcm-builder/src/weight.rs

@@ -80,18 +80,13 @@ impl<T: Get<Weight>, C: Decode + GetDispatchInfo> FixedWeightBounds<T, C> {
 	}
 	fn deep_order(order: &mut Order<C>) -> Result<Weight, ()> {
 		Ok(match order {
-			Order::BuyExecution { orders, instructions, .. } => {
+			Order::BuyExecution { instructions, .. } => {
 				let mut extra = 0;
 				for instruction in instructions.iter_mut() {
 					extra.saturating_accrue(
 						Self::shallow(instruction)?.saturating_add(Self::deep(instruction)?),
 					);
 				}
-				for order in orders.iter_mut() {
-					extra.saturating_accrue(
-						Self::shallow_order(order)?.saturating_add(Self::deep_order(order)?),
-					);
-				}
 				extra
 			},
 			_ => 0,

polkadot/xcm/xcm-executor/integration-tests/src/lib.rs

@@ -46,7 +46,6 @@ fn execute_within_recursion_limit() {
 				weight: 0,
 				debt: 0,
 				halt_on_error: true,
-				orders: vec![],
 				// nest `msg` into itself on each iteration.
 				instructions: vec![msg],
 			}],
@@ -101,7 +100,6 @@ fn exceed_recursion_limit() {
 				weight: 0,
 				debt: 0,
 				halt_on_error: true,
-				orders: vec![],
 				// nest `msg` into itself on each iteration.
 				instructions: vec![msg],
 			}],

polkadot/xcm/xcm-executor/src/lib.rs

@@ -332,7 +332,7 @@ impl<Config: config::Config> XcmExecutor<Config> {
 					Xcm::QueryResponse { query_id, response: Response::Assets(assets) },
 				)?;
 			},
-			Order::BuyExecution { fees, weight, debt, halt_on_error, orders, instructions } => {
+			Order::BuyExecution { fees, weight, debt, halt_on_error, instructions } => {
 				// pay for `weight` using up to `fees` of the holding register.
 				let purchasing_weight =
 					Weight::from(weight.checked_add(debt).ok_or(XcmError::Overflow)?);
@@ -342,13 +342,6 @@ impl<Config: config::Config> XcmExecutor<Config> {
 				holding.subsume_assets(unspent);
 
 				let mut remaining_weight = weight;
-				for order in orders.into_iter() {
-					match Self::execute_orders(origin, holding, order, trader, num_recursions + 1) {
-						Err(e) if halt_on_error => return Err(e),
-						Err(_) => {},
-						Ok(surplus) => total_surplus += surplus,
-					}
-				}
 				for instruction in instructions.into_iter() {
 					match Self::do_execute_xcm(
 						origin.clone(),