Update bridges subtree (#1392)

* Move the bridges subtree under root

* Squashed 'bridges/' changes from 277f0d5496..e50398d1c5

e50398d1c5 bridges subtree fixes (#2528)
99af07522d Markdown linter (#1309) (#2526)
733ff0fe7a `polkadot-staging` branch: Use polkadot-sdk dependencies (#2524)
e8a59f141e Fix benchmark with new XCM::V3 `MAX_INSTRUCTIONS_TO_DECODE` (#2514)
62b185de15 Backport `polkadot-sdk` changes to `polkadot-staging` (#2518)
d9658f4d5b Fix equivocation detection containers startup (#2516) (#2517)
d65db28a8f Backport: building images from locally built binaries (#2513)
5fdbaf45f6 Start the equivocation detection loop from the complex relayer (#2507) (#2512)
7fbb67de46 Backport: Implement basic equivocations detection loop (#2375)
cb7efe245c Manually update deps in polkadot staging (#2371)
d17981fc33 #2351 to polkadot-staging (#2359)

git-subtree-dir: bridges
git-subtree-split: e50398d1c594e4e96df70b0bd376e565d17e8558

* Reapply diener workspacify

* Fix Cargo.toml

* Fix test

* Adjustments

bridges/modules/relayers/src/stake_adapter.rs

@@ -0,0 +1,186 @@
+// Copyright (C) Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity Bridges Common is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Code that allows `NamedReservableCurrency` to be used as a `StakeAndSlash`
+//! mechanism of the relayers pallet.
+
+use bp_relayers::{PayRewardFromAccount, RewardsAccountParams, StakeAndSlash};
+use codec::Codec;
+use frame_support::traits::{tokens::BalanceStatus, NamedReservableCurrency};
+use sp_runtime::{traits::Get, DispatchError, DispatchResult};
+use sp_std::{fmt::Debug, marker::PhantomData};
+
+/// `StakeAndSlash` that works with `NamedReservableCurrency` and uses named
+/// reservations.
+///
+/// **WARNING**: this implementation assumes that the relayers pallet is configured to
+/// use the [`bp_relayers::PayRewardFromAccount`] as its relayers payment scheme.
+pub struct StakeAndSlashNamed<AccountId, BlockNumber, Currency, ReserveId, Stake, Lease>(
+	PhantomData<(AccountId, BlockNumber, Currency, ReserveId, Stake, Lease)>,
+);
+
+impl<AccountId, BlockNumber, Currency, ReserveId, Stake, Lease>
+	StakeAndSlash<AccountId, BlockNumber, Currency::Balance>
+	for StakeAndSlashNamed<AccountId, BlockNumber, Currency, ReserveId, Stake, Lease>
+where
+	AccountId: Codec + Debug,
+	Currency: NamedReservableCurrency<AccountId>,
+	ReserveId: Get<Currency::ReserveIdentifier>,
+	Stake: Get<Currency::Balance>,
+	Lease: Get<BlockNumber>,
+{
+	type RequiredStake = Stake;
+	type RequiredRegistrationLease = Lease;
+
+	fn reserve(relayer: &AccountId, amount: Currency::Balance) -> DispatchResult {
+		Currency::reserve_named(&ReserveId::get(), relayer, amount)
+	}
+
+	fn unreserve(relayer: &AccountId, amount: Currency::Balance) -> Currency::Balance {
+		Currency::unreserve_named(&ReserveId::get(), relayer, amount)
+	}
+
+	fn repatriate_reserved(
+		relayer: &AccountId,
+		beneficiary: RewardsAccountParams,
+		amount: Currency::Balance,
+	) -> Result<Currency::Balance, DispatchError> {
+		let beneficiary_account =
+			PayRewardFromAccount::<(), AccountId>::rewards_account(beneficiary);
+		Currency::repatriate_reserved_named(
+			&ReserveId::get(),
+			relayer,
+			&beneficiary_account,
+			amount,
+			BalanceStatus::Free,
+		)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use crate::mock::*;
+
+	use frame_support::traits::fungible::Mutate;
+
+	fn test_stake() -> Balance {
+		Stake::get()
+	}
+
+	#[test]
+	fn reserve_works() {
+		run_test(|| {
+			assert!(TestStakeAndSlash::reserve(&1, test_stake()).is_err());
+			assert_eq!(Balances::free_balance(1), 0);
+			assert_eq!(Balances::reserved_balance(1), 0);
+
+			Balances::mint_into(&2, test_stake() - 1).unwrap();
+			assert!(TestStakeAndSlash::reserve(&2, test_stake()).is_err());
+			assert_eq!(Balances::free_balance(2), test_stake() - 1);
+			assert_eq!(Balances::reserved_balance(2), 0);
+
+			Balances::mint_into(&3, test_stake() * 2).unwrap();
+			assert_eq!(TestStakeAndSlash::reserve(&3, test_stake()), Ok(()));
+			assert_eq!(Balances::free_balance(3), test_stake());
+			assert_eq!(Balances::reserved_balance(3), test_stake());
+		})
+	}
+
+	#[test]
+	fn unreserve_works() {
+		run_test(|| {
+			assert_eq!(TestStakeAndSlash::unreserve(&1, test_stake()), test_stake());
+			assert_eq!(Balances::free_balance(1), 0);
+			assert_eq!(Balances::reserved_balance(1), 0);
+
+			Balances::mint_into(&2, test_stake() * 2).unwrap();
+			TestStakeAndSlash::reserve(&2, test_stake() / 3).unwrap();
+			assert_eq!(
+				TestStakeAndSlash::unreserve(&2, test_stake()),
+				test_stake() - test_stake() / 3
+			);
+			assert_eq!(Balances::free_balance(2), test_stake() * 2);
+			assert_eq!(Balances::reserved_balance(2), 0);
+
+			Balances::mint_into(&3, test_stake() * 2).unwrap();
+			TestStakeAndSlash::reserve(&3, test_stake()).unwrap();
+			assert_eq!(TestStakeAndSlash::unreserve(&3, test_stake()), 0);
+			assert_eq!(Balances::free_balance(3), test_stake() * 2);
+			assert_eq!(Balances::reserved_balance(3), 0);
+		})
+	}
+
+	#[test]
+	fn repatriate_reserved_works() {
+		run_test(|| {
+			let beneficiary = TEST_REWARDS_ACCOUNT_PARAMS;
+			let beneficiary_account = TestPaymentProcedure::rewards_account(beneficiary);
+
+			let mut expected_balance = ExistentialDeposit::get();
+			Balances::mint_into(&beneficiary_account, expected_balance).unwrap();
+
+			assert_eq!(
+				TestStakeAndSlash::repatriate_reserved(&1, beneficiary, test_stake()),
+				Ok(test_stake())
+			);
+			assert_eq!(Balances::free_balance(1), 0);
+			assert_eq!(Balances::reserved_balance(1), 0);
+			assert_eq!(Balances::free_balance(beneficiary_account), expected_balance);
+			assert_eq!(Balances::reserved_balance(beneficiary_account), 0);
+
+			expected_balance += test_stake() / 3;
+			Balances::mint_into(&2, test_stake() * 2).unwrap();
+			TestStakeAndSlash::reserve(&2, test_stake() / 3).unwrap();
+			assert_eq!(
+				TestStakeAndSlash::repatriate_reserved(&2, beneficiary, test_stake()),
+				Ok(test_stake() - test_stake() / 3)
+			);
+			assert_eq!(Balances::free_balance(2), test_stake() * 2 - test_stake() / 3);
+			assert_eq!(Balances::reserved_balance(2), 0);
+			assert_eq!(Balances::free_balance(beneficiary_account), expected_balance);
+			assert_eq!(Balances::reserved_balance(beneficiary_account), 0);
+
+			expected_balance += test_stake();
+			Balances::mint_into(&3, test_stake() * 2).unwrap();
+			TestStakeAndSlash::reserve(&3, test_stake()).unwrap();
+			assert_eq!(
+				TestStakeAndSlash::repatriate_reserved(&3, beneficiary, test_stake()),
+				Ok(0)
+			);
+			assert_eq!(Balances::free_balance(3), test_stake());
+			assert_eq!(Balances::reserved_balance(3), 0);
+			assert_eq!(Balances::free_balance(beneficiary_account), expected_balance);
+			assert_eq!(Balances::reserved_balance(beneficiary_account), 0);
+		})
+	}
+
+	#[test]
+	fn repatriate_reserved_doesnt_work_when_beneficiary_account_is_missing() {
+		run_test(|| {
+			let beneficiary = TEST_REWARDS_ACCOUNT_PARAMS;
+			let beneficiary_account = TestPaymentProcedure::rewards_account(beneficiary);
+
+			Balances::mint_into(&3, test_stake() * 2).unwrap();
+			TestStakeAndSlash::reserve(&3, test_stake()).unwrap();
+			assert!(TestStakeAndSlash::repatriate_reserved(&3, beneficiary, test_stake()).is_err());
+			assert_eq!(Balances::free_balance(3), test_stake());
+			assert_eq!(Balances::reserved_balance(3), test_stake());
+			assert_eq!(Balances::free_balance(beneficiary_account), 0);
+			assert_eq!(Balances::reserved_balance(beneficiary_account), 0);
+		});
+	}
+}