fix clippy errors

substrate/frame/delegated-staking/src/impls.rs

@@ -54,7 +54,7 @@ impl<T: Config> StakingInterface for Pallet<T> {
 
 	fn stake(who: &Self::AccountId) -> Result<Stake<Self::Balance>, DispatchError> {
 		ensure!(Self::is_delegatee(who), Error::<T>::NotSupported);
-		return T::CoreStaking::stake(who);
+		T::CoreStaking::stake(who)
 	}
 
 	fn total_stake(who: &Self::AccountId) -> Result<Self::Balance, DispatchError> {
@@ -80,7 +80,7 @@ impl<T: Config> StakingInterface for Pallet<T> {
 
 	fn fully_unbond(who: &Self::AccountId) -> DispatchResult {
 		ensure!(Self::is_delegatee(who), Error::<T>::NotSupported);
-		return T::CoreStaking::fully_unbond(who);
+		T::CoreStaking::fully_unbond(who)
 	}
 
 	fn bond(
@@ -100,12 +100,12 @@ impl<T: Config> StakingInterface for Pallet<T> {
 
 	fn nominate(who: &Self::AccountId, validators: Vec<Self::AccountId>) -> DispatchResult {
 		ensure!(Self::is_delegatee(who), Error::<T>::NotDelegatee);
-		return T::CoreStaking::nominate(who, validators);
+		T::CoreStaking::nominate(who, validators)
 	}
 
 	fn chill(who: &Self::AccountId) -> DispatchResult {
 		ensure!(Self::is_delegatee(who), Error::<T>::NotDelegatee);
-		return T::CoreStaking::chill(who);
+		T::CoreStaking::chill(who)
 	}
 
 	fn bond_extra(who: &Self::AccountId, extra: Self::Balance) -> DispatchResult {

substrate/frame/delegated-staking/src/lib.rs

@@ -54,9 +54,9 @@
 //! - **Delegatee**: An account who accepts delegations from other accounts.
 //! - **Delegator**: An account who delegates their funds to a `delegatee`.
 //! - **DelegateeLedger**: A data structure that stores important information about the `delegatee`
-//! 	such as their total delegated stake.
+//!   such as their total delegated stake.
 //! - **Delegation**: A data structure that stores the amount of funds delegated to a `delegatee` by
-//! 	a `delegator`.
+//!   a `delegator`.
 //!
 //! ## Interface
 //!
@@ -129,7 +129,7 @@
 //! ## Limitations
 //! - Rewards can not be auto-compounded.
 //! - Slashes are lazy and hence there could be a period of time when an account can use funds for
-//! 	operations such as voting in governance even though they should be slashed.
+//!   operations such as voting in governance even though they should be slashed.
 
 #![cfg_attr(not(feature = "std"), no_std)]
 #![deny(rustdoc::broken_intra_doc_links)]
@@ -469,7 +469,7 @@ impl<T: Config> Pallet<T> {
 
 	/// Returns true if who is not already staking on [`Config::CoreStaking`].
 	fn not_direct_staker(who: &T::AccountId) -> bool {
-		T::CoreStaking::status(&who).is_err()
+		T::CoreStaking::status(who).is_err()
 	}
 
 	/// Returns true if who is a [`StakerStatus::Nominator`] on [`Config::CoreStaking`].
@@ -531,7 +531,7 @@ impl<T: Config> Pallet<T> {
 		if delegatee.is_bonded() {
 			T::CoreStaking::bond_extra(&delegatee.key, amount)
 		} else {
-			T::CoreStaking::virtual_bond(&delegatee.key, amount, &delegatee.reward_account())
+			T::CoreStaking::virtual_bond(&delegatee.key, amount, delegatee.reward_account())
 		}
 	}
 
@@ -605,7 +605,7 @@ impl<T: Config> Pallet<T> {
 
 		let released = T::Currency::release(
 			&HoldReason::Delegating.into(),
-			&delegator,
+			delegator,
 			amount,
 			Precision::BestEffort,
 		)?;
@@ -658,7 +658,7 @@ impl<T: Config> Pallet<T> {
 		amount: BalanceOf<T>,
 	) -> DispatchResult {
 		let source_delegation =
-			Delegators::<T>::get(&source_delegator).defensive_ok_or(Error::<T>::BadState)?;
+			Delegators::<T>::get(source_delegator).defensive_ok_or(Error::<T>::BadState)?;
 
 		// some checks that must have already been checked before.
 		ensure!(source_delegation.amount >= amount, Error::<T>::NotEnoughFunds);
@@ -679,7 +679,7 @@ impl<T: Config> Pallet<T> {
 		// release funds from source
 		let released = T::Currency::release(
 			&HoldReason::Delegating.into(),
-			&source_delegator,
+			source_delegator,
 			amount,
 			Precision::BestEffort,
 		)?;
@@ -689,15 +689,15 @@ impl<T: Config> Pallet<T> {
 		// transfer the released amount to `destination_delegator`.
 		// Note: The source should have been funded ED in the beginning so it should not be dusted.
 		T::Currency::transfer(
-			&source_delegator,
+			source_delegator,
 			destination_delegator,
 			amount,
 			Preservation::Preserve,
 		)
 		.map_err(|_| Error::<T>::BadState)?;
 
 		// hold the funds again in the new delegator account.
-		T::Currency::hold(&HoldReason::Delegating.into(), &destination_delegator, amount)?;
+		T::Currency::hold(&HoldReason::Delegating.into(), destination_delegator, amount)?;
 
 		Ok(())
 	}

substrate/frame/delegated-staking/src/mock.rs

@@ -176,14 +176,9 @@ frame_support::construct_runtime!(
 	}
 );
 
+#[derive(Default)]
 pub struct ExtBuilder {}
 
-impl Default for ExtBuilder {
-	fn default() -> Self {
-		Self {}
-	}
-}
-
 impl ExtBuilder {
 	fn build(self) -> sp_io::TestExternalities {
 		sp_tracing::try_init_simple();
@@ -242,7 +237,7 @@ impl ExtBuilder {
 
 		ext
 	}
-	pub fn build_and_execute(self, test: impl FnOnce() -> ()) {
+	pub fn build_and_execute(self, test: impl FnOnce()) {
 		sp_tracing::try_init_simple();
 		let mut ext = self.build();
 		ext.execute_with(test);
@@ -280,7 +275,7 @@ pub(crate) fn setup_delegation_stake(
 
 		fund(delegator, amount_to_delegate + ExistentialDeposit::get());
 		assert_ok!(DelegatedStaking::delegate_funds(
-			RawOrigin::Signed(delegator.clone()).into(),
+			RawOrigin::Signed(*delegator).into(),
 			delegatee,
 			amount_to_delegate
 		));
@@ -306,15 +301,16 @@ pub(crate) fn get_delegatee(delegatee: &AccountId) -> Delegatee<T> {
 	Delegatee::<T>::from(delegatee).expect("delegate should exist")
 }
 
-
+#[allow(unused)]
 pub(crate) fn held_balance(who: &AccountId) -> Balance {
-	Balances::balance_on_hold(&HoldReason::Delegating.into(), &who)
+	Balances::balance_on_hold(&HoldReason::Delegating.into(), who)
 }
 
 parameter_types! {
 	static ObservedEventsDelegatedStaking: usize = 0;
 }
 
+#[allow(unused)]
 pub(crate) fn events_since_last_call() -> Vec<crate::Event<Runtime>> {
 	let events = System::events()
 		.into_iter()

substrate/frame/delegated-staking/src/tests.rs

@@ -198,9 +198,7 @@ fn delegatee_restrictions() {
 #[test]
 fn apply_pending_slash() {
 	ExtBuilder::default().build_and_execute(|| {
-		(
-        // fixme(ank4n): add tests for apply_pending_slash
-        )
+		// fixme(ank4n): add tests for apply_pending_slash
 	});
 }
 
@@ -538,4 +536,4 @@ mod staking_integration {
 			);
 		});
 	}
-}
+}

substrate/frame/delegated-staking/src/types.rs

@@ -290,6 +290,7 @@ impl<T: Config> Delegatee<T> {
 
 	/// Reloads self from storage.
 	#[cfg(test)]
+	#[allow(unused)]
 	pub(crate) fn refresh(&self) -> Result<Delegatee<T>, DispatchError> {
 		Self::from(&self.key)
 	}
@@ -299,6 +300,7 @@ impl<T: Config> Delegatee<T> {
 	/// This is similar to [Self::available_to_bond] except it also includes `unclaimed_withdrawals`
 	/// of `Delegatee`.
 	#[cfg(test)]
+	#[allow(unused)]
 	pub(crate) fn total_unbonded(&self) -> BalanceOf<T> {
 		let bonded_stake = self.bonded_stake();