Rename pallet trait Trait to Config (#7599)

* rename Trait to Config

* add test asserting using Trait is still valid.

* fix ui tests

substrate/frame/staking/src/slashing.rs

@@ -50,7 +50,7 @@
 //! Based on research at https://research.web3.foundation/en/latest/polkadot/slashing/npos/
 
 use super::{
-	EraIndex, Trait, Module, Store, BalanceOf, Exposure, Perbill, SessionInterface,
+	EraIndex, Config, Module, Store, BalanceOf, Exposure, Perbill, SessionInterface,
 	NegativeImbalanceOf, UnappliedSlash, Error,
 };
 use sp_runtime::{traits::{Zero, Saturating}, RuntimeDebug, DispatchResult};
@@ -190,7 +190,7 @@ impl<Balance> SpanRecord<Balance> {
 
 /// Parameters for performing a slash.
 #[derive(Clone)]
-pub(crate) struct SlashParams<'a, T: 'a + Trait> {
+pub(crate) struct SlashParams<'a, T: 'a + Config> {
 	/// The stash account being slashed.
 	pub(crate) stash: &'a T::AccountId,
 	/// The proportion of the slash.
@@ -214,7 +214,7 @@ pub(crate) struct SlashParams<'a, T: 'a + Trait> {
 ///
 /// The pending slash record returned does not have initialized reporters. Those have
 /// to be set at a higher level, if any.
-pub(crate) fn compute_slash<T: Trait>(params: SlashParams<T>)
+pub(crate) fn compute_slash<T: Config>(params: SlashParams<T>)
 	-> Option<UnappliedSlash<T::AccountId, BalanceOf<T>>>
 {
 	let SlashParams {
@@ -309,7 +309,7 @@ pub(crate) fn compute_slash<T: Trait>(params: SlashParams<T>)
 
 // doesn't apply any slash, but kicks out the validator if the misbehavior is from
 // the most recent slashing span.
-fn kick_out_if_recent<T: Trait>(
+fn kick_out_if_recent<T: Config>(
 	params: SlashParams<T>,
 ) {
 	// these are not updated by era-span or end-span.
@@ -338,7 +338,7 @@ fn kick_out_if_recent<T: Trait>(
 /// Slash nominators. Accepts general parameters and the prior slash percentage of the validator.
 ///
 /// Returns the amount of reward to pay out.
-fn slash_nominators<T: Trait>(
+fn slash_nominators<T: Config>(
 	params: SlashParams<T>,
 	prior_slash_p: Perbill,
 	nominators_slashed: &mut Vec<(T::AccountId, BalanceOf<T>)>,
@@ -418,7 +418,7 @@ fn slash_nominators<T: Trait>(
 // dropping this struct applies any necessary slashes, which can lead to free balance
 // being 0, and the account being garbage-collected -- a dead account should get no new
 // metadata.
-struct InspectingSpans<'a, T: Trait + 'a> {
+struct InspectingSpans<'a, T: Config + 'a> {
 	dirty: bool,
 	window_start: EraIndex,
 	stash: &'a T::AccountId,
@@ -430,7 +430,7 @@ struct InspectingSpans<'a, T: Trait + 'a> {
 }
 
 // fetches the slashing spans record for a stash account, initializing it if necessary.
-fn fetch_spans<'a, T: Trait + 'a>(
+fn fetch_spans<'a, T: Config + 'a>(
 	stash: &'a T::AccountId,
 	window_start: EraIndex,
 	paid_out: &'a mut BalanceOf<T>,
@@ -455,7 +455,7 @@ fn fetch_spans<'a, T: Trait + 'a>(
 	}
 }
 
-impl<'a, T: 'a + Trait> InspectingSpans<'a, T> {
+impl<'a, T: 'a + Config> InspectingSpans<'a, T> {
 	fn span_index(&self) -> SpanIndex {
 		self.spans.span_index
 	}
@@ -526,7 +526,7 @@ impl<'a, T: 'a + Trait> InspectingSpans<'a, T> {
 	}
 }
 
-impl<'a, T: 'a + Trait> Drop for InspectingSpans<'a, T> {
+impl<'a, T: 'a + Config> Drop for InspectingSpans<'a, T> {
 	fn drop(&mut self) {
 		// only update on disk if we slashed this account.
 		if !self.dirty { return }
@@ -542,13 +542,13 @@ impl<'a, T: 'a + Trait> Drop for InspectingSpans<'a, T> {
 }
 
 /// Clear slashing metadata for an obsolete era.
-pub(crate) fn clear_era_metadata<T: Trait>(obsolete_era: EraIndex) {
+pub(crate) fn clear_era_metadata<T: Config>(obsolete_era: EraIndex) {
 	<Module<T> as Store>::ValidatorSlashInEra::remove_prefix(&obsolete_era);
 	<Module<T> as Store>::NominatorSlashInEra::remove_prefix(&obsolete_era);
 }
 
 /// Clear slashing metadata for a dead account.
-pub(crate) fn clear_stash_metadata<T: Trait>(
+pub(crate) fn clear_stash_metadata<T: Config>(
 	stash: &T::AccountId,
 	num_slashing_spans: u32,
 ) -> DispatchResult {
@@ -576,7 +576,7 @@ pub(crate) fn clear_stash_metadata<T: Trait>(
 // apply the slash to a stash account, deducting any missing funds from the reward
 // payout, saturating at 0. this is mildly unfair but also an edge-case that
 // can only occur when overlapping locked funds have been slashed.
-pub fn do_slash<T: Trait>(
+pub fn do_slash<T: Config>(
 	stash: &T::AccountId,
 	value: BalanceOf<T>,
 	reward_payout: &mut BalanceOf<T>,
@@ -613,7 +613,7 @@ pub fn do_slash<T: Trait>(
 }
 
 /// Apply a previously-unapplied slash.
-pub(crate) fn apply_slash<T: Trait>(unapplied_slash: UnappliedSlash<T::AccountId, BalanceOf<T>>) {
+pub(crate) fn apply_slash<T: Config>(unapplied_slash: UnappliedSlash<T::AccountId, BalanceOf<T>>) {
 	let mut slashed_imbalance = NegativeImbalanceOf::<T>::zero();
 	let mut reward_payout = unapplied_slash.payout;
 
@@ -638,7 +638,7 @@ pub(crate) fn apply_slash<T: Trait>(unapplied_slash: UnappliedSlash<T::AccountId
 
 
 /// Apply a reward payout to some reporters, paying the rewards out of the slashed imbalance.
-fn pay_reporters<T: Trait>(
+fn pay_reporters<T: Config>(
 	reward_payout: BalanceOf<T>,
 	slashed_imbalance: NegativeImbalanceOf<T>,
 	reporters: &[T::AccountId],