Contracts: Refactor test builder (#4158)

- Moved `substrate/frame/contracts/src/tests/builder.rs` into a pub
test_utils module, so we can use that in the
`pallet-contracts-mock-network` tests
- Refactor xcm tests to use XCM builders, and simplify the use case for
xcm-send

substrate/frame/contracts/mock-network/src/lib.rs

@@ -23,6 +23,7 @@ pub mod relay_chain;
 mod tests;
 
 use crate::primitives::{AccountId, UNITS};
+pub use pallet_contracts::test_utils::{ALICE, BOB};
 use sp_runtime::BuildStorage;
 use xcm::latest::prelude::*;
 use xcm_executor::traits::ConvertLocation;
@@ -31,8 +32,6 @@ use xcm_simulator::{decl_test_network, decl_test_parachain, decl_test_relay_chai
 
 // Accounts
 pub const ADMIN: sp_runtime::AccountId32 = sp_runtime::AccountId32::new([0u8; 32]);
-pub const ALICE: sp_runtime::AccountId32 = sp_runtime::AccountId32::new([1u8; 32]);
-pub const BOB: sp_runtime::AccountId32 = sp_runtime::AccountId32::new([2u8; 32]);
 
 // Balances
 pub const INITIAL_BALANCE: u128 = 1_000_000_000 * UNITS;

substrate/frame/contracts/mock-network/src/tests.rs

@@ -22,45 +22,31 @@ use crate::{
 	relay_chain, MockNet, ParaA, ParachainBalances, Relay, ALICE, BOB, INITIAL_BALANCE,
 };
 use codec::{Decode, Encode};
-use frame_support::{
-	pallet_prelude::Weight,
-	traits::{fungibles::Mutate, Currency},
-};
-use pallet_balances::{BalanceLock, Reasons};
-use pallet_contracts::{Code, CollectEvents, DebugInfo, Determinism};
+use frame_support::traits::{fungibles::Mutate, Currency};
+use pallet_contracts::{test_utils::builder::*, Code};
 use pallet_contracts_fixtures::compile_module;
 use pallet_contracts_uapi::ReturnErrorCode;
 use xcm::{v4::prelude::*, VersionedLocation, VersionedXcm};
 use xcm_simulator::TestExt;
 
-type ParachainContracts = pallet_contracts::Pallet<parachain::Runtime>;
-
 macro_rules! assert_return_code {
 	( $x:expr , $y:expr $(,)? ) => {{
 		assert_eq!(u32::from_le_bytes($x.data[..].try_into().unwrap()), $y as u32);
 	}};
 }
 
+fn bare_call(dest: sp_runtime::AccountId32) -> BareCallBuilder<parachain::Runtime> {
+	BareCallBuilder::<parachain::Runtime>::bare_call(ALICE, dest)
+}
+
 /// Instantiate the tests contract, and fund it with some balance and assets.
 fn instantiate_test_contract(name: &str) -> AccountId {
 	let (wasm, _) = compile_module::<Runtime>(name).unwrap();
 
 	// Instantiate contract.
 	let contract_addr = ParaA::execute_with(|| {
-		ParachainContracts::bare_instantiate(
-			ALICE,
-			0,
-			Weight::MAX,
-			None,
-			Code::Upload(wasm),
-			vec![],
-			vec![],
-			DebugInfo::UnsafeDebug,
-			CollectEvents::Skip,
-		)
-		.result
-		.unwrap()
-		.account_id
+		BareInstantiateBuilder::<parachain::Runtime>::bare_instantiate(ALICE, Code::Upload(wasm))
+			.build_and_unwrap_account_id()
 	});
 
 	// Funds contract account with some balance and assets.
@@ -85,27 +71,18 @@ fn test_xcm_execute() {
 	// Execute XCM instructions through the contract.
 	ParaA::execute_with(|| {
 		let amount: u128 = 10 * CENTS;
+		let assets: Asset = (Here, amount).into();
+		let beneficiary = AccountId32 { network: None, id: BOB.clone().into() };
 
 		// The XCM used to transfer funds to Bob.
-		let message: Xcm<()> = Xcm(vec![
-			WithdrawAsset(vec![(Here, amount).into()].into()),
-			DepositAsset {
-				assets: All.into(),
-				beneficiary: AccountId32 { network: None, id: BOB.clone().into() }.into(),
-			},
-		]);
-
-		let result = ParachainContracts::bare_call(
-			ALICE,
-			contract_addr.clone(),
-			0,
-			Weight::MAX,
-			None,
-			VersionedXcm::V4(message).encode().encode(),
-			DebugInfo::UnsafeDebug,
-			CollectEvents::UnsafeCollect,
-			Determinism::Enforced,
-		);
+		let message: Xcm<()> = Xcm::builder_unsafe()
+			.withdraw_asset(assets.clone())
+			.deposit_asset(assets, beneficiary)
+			.build();
+
+		let result = bare_call(contract_addr.clone())
+			.data(VersionedXcm::V4(message).encode().encode())
+			.build();
 
 		assert_eq!(result.gas_consumed, result.gas_required);
 		assert_return_code!(&result.result.unwrap(), ReturnErrorCode::Success);
@@ -127,29 +104,22 @@ fn test_xcm_execute_incomplete() {
 
 	// Execute XCM instructions through the contract.
 	ParaA::execute_with(|| {
+		let assets: Asset = (Here, amount).into();
+		let beneficiary = AccountId32 { network: None, id: BOB.clone().into() };
+
 		// The XCM used to transfer funds to Bob.
-		let message: Xcm<()> = Xcm(vec![
-			WithdrawAsset(vec![(Here, amount).into()].into()),
+		let message: Xcm<()> = Xcm::builder_unsafe()
+			.withdraw_asset(assets.clone())
 			// This will fail as the contract does not have enough balance to complete both
 			// withdrawals.
-			WithdrawAsset(vec![(Here, INITIAL_BALANCE).into()].into()),
-			DepositAsset {
-				assets: All.into(),
-				beneficiary: AccountId32 { network: None, id: BOB.clone().into() }.into(),
-			},
-		]);
-
-		let result = ParachainContracts::bare_call(
-			ALICE,
-			contract_addr.clone(),
-			0,
-			Weight::MAX,
-			None,
-			VersionedXcm::V4(message).encode().encode(),
-			DebugInfo::UnsafeDebug,
-			CollectEvents::UnsafeCollect,
-			Determinism::Enforced,
-		);
+			.withdraw_asset((Here, INITIAL_BALANCE))
+			.buy_execution(assets.clone(), Unlimited)
+			.deposit_asset(assets, beneficiary)
+			.build();
+
+		let result = bare_call(contract_addr.clone())
+			.data(VersionedXcm::V4(message).encode().encode())
+			.build();
 
 		assert_eq!(result.gas_consumed, result.gas_required);
 		assert_return_code!(&result.result.unwrap(), ReturnErrorCode::XcmExecutionFailed);
@@ -175,28 +145,16 @@ fn test_xcm_execute_reentrant_call() {
 		});
 
 		// The XCM used to transfer funds to Bob.
-		let message: Xcm<parachain::RuntimeCall> = Xcm(vec![
-			Transact {
-				origin_kind: OriginKind::Native,
-				require_weight_at_most: 1_000_000_000.into(),
-				call: transact_call.encode().into(),
-			},
-			ExpectTransactStatus(MaybeErrorCode::Success),
-		]);
-
-		let result = ParachainContracts::bare_call(
-			ALICE,
-			contract_addr.clone(),
-			0,
-			Weight::MAX,
-			None,
-			VersionedXcm::V4(message).encode().encode(),
-			DebugInfo::UnsafeDebug,
-			CollectEvents::UnsafeCollect,
-			Determinism::Enforced,
-		);
+		let message: Xcm<parachain::RuntimeCall> = Xcm::builder_unsafe()
+			.transact(OriginKind::Native, 1_000_000_000, transact_call.encode())
+			.expect_transact_status(MaybeErrorCode::Success)
+			.build();
 
-		assert_return_code!(&result.result.unwrap(), ReturnErrorCode::XcmExecutionFailed);
+		let result = bare_call(contract_addr.clone())
+			.data(VersionedXcm::V4(message).encode().encode())
+			.build_and_unwrap_result();
+
+		assert_return_code!(&result, ReturnErrorCode::XcmExecutionFailed);
 
 		// Funds should not change hands as the XCM transact failed.
 		assert_eq!(ParachainBalances::free_balance(BOB), INITIAL_BALANCE);
@@ -207,40 +165,36 @@ fn test_xcm_execute_reentrant_call() {
 fn test_xcm_send() {
 	MockNet::reset();
 	let contract_addr = instantiate_test_contract("xcm_send");
+	let amount = 1_000 * CENTS;
 	let fee = parachain::estimate_message_fee(4); // Accounts for the `DescendOrigin` instruction added by `send_xcm`
 
-	// Send XCM instructions through the contract, to lock some funds on the relay chain.
+	// Send XCM instructions through the contract, to transfer some funds from the contract
+	// derivative account to Alice on the relay chain.
 	ParaA::execute_with(|| {
-		let dest = Location::from(Parent);
-		let dest = VersionedLocation::V4(dest);
-
-		let message: Xcm<()> = Xcm(vec![
-			WithdrawAsset((Here, fee).into()),
-			BuyExecution { fees: (Here, fee).into(), weight_limit: WeightLimit::Unlimited },
-			LockAsset { asset: (Here, 5 * CENTS).into(), unlocker: (Parachain(1)).into() },
-		]);
-		let message = VersionedXcm::V4(message);
-		let exec = ParachainContracts::bare_call(
-			ALICE,
-			contract_addr.clone(),
-			0,
-			Weight::MAX,
-			None,
-			(dest, message.encode()).encode(),
-			DebugInfo::UnsafeDebug,
-			CollectEvents::UnsafeCollect,
-			Determinism::Enforced,
-		);
+		let dest = VersionedLocation::V4(Parent.into());
+		let assets: Asset = (Here, amount).into();
+		let beneficiary = AccountId32 { network: None, id: ALICE.clone().into() };
+
+		let message: Xcm<()> = Xcm::builder()
+			.withdraw_asset(assets.clone())
+			.buy_execution((Here, fee), Unlimited)
+			.deposit_asset(assets, beneficiary)
+			.build();
+
+		let result = bare_call(contract_addr.clone())
+			.data((dest, VersionedXcm::V4(message).encode()).encode())
+			.build_and_unwrap_result();
 
-		let mut data = &exec.result.unwrap().data[..];
+		let mut data = &result.data[..];
 		XcmHash::decode(&mut data).expect("Failed to decode xcm_send message_id");
 	});
 
 	Relay::execute_with(|| {
-		// Check if the funds are locked on the relay chain.
+		let derived_contract_addr = &parachain_account_sovereign_account_id(1, contract_addr);
 		assert_eq!(
-			relay_chain::Balances::locks(&parachain_account_sovereign_account_id(1, contract_addr)),
-			vec![BalanceLock { id: *b"py/xcmlk", amount: 5 * CENTS, reasons: Reasons::All }]
+			INITIAL_BALANCE - amount,
+			relay_chain::Balances::free_balance(derived_contract_addr)
 		);
+		assert_eq!(INITIAL_BALANCE + amount - fee, relay_chain::Balances::free_balance(ALICE));
 	});
 }

substrate/frame/contracts/src/lib.rs

@@ -101,6 +101,7 @@ mod wasm;
 pub mod chain_extension;
 pub mod debug;
 pub mod migration;
+pub mod test_utils;
 pub mod weights;
 
 #[cfg(test)]

substrate/frame/contracts/src/test_utils.rs

@@ -0,0 +1,30 @@
+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Shared utilities for testing contracts.
+//! This is not part of the tests module because it is made public for other crates to use.
+#![cfg(feature = "std")]
+use frame_support::weights::Weight;
+pub use sp_runtime::AccountId32;
+
+pub const ALICE: AccountId32 = AccountId32::new([1u8; 32]);
+pub const BOB: AccountId32 = AccountId32::new([2u8; 32]);
+pub const CHARLIE: AccountId32 = AccountId32::new([3u8; 32]);
+pub const DJANGO: AccountId32 = AccountId32::new([4u8; 32]);
+
+pub const GAS_LIMIT: Weight = Weight::from_parts(100_000_000_000, 3 * 1024 * 1024);
+pub mod builder;