Rename pallet trait Trait to Config (#7599)

* rename Trait to Config

* add test asserting using Trait is still valid.

* fix ui tests

substrate/frame/elections/src/lib.rs

@@ -139,9 +139,9 @@ pub const VOTER_SET_SIZE: usize = 64;
 /// NUmber of approvals grouped in one chunk.
 pub const APPROVAL_SET_SIZE: usize = 8;
 
-type BalanceOf<T> = <<T as Trait>::Currency as Currency<<T as frame_system::Trait>::AccountId>>::Balance;
+type BalanceOf<T> = <<T as Config>::Currency as Currency<<T as frame_system::Config>::AccountId>>::Balance;
 type NegativeImbalanceOf<T> =
-	<<T as Trait>::Currency as Currency<<T as frame_system::Trait>::AccountId>>::NegativeImbalance;
+	<<T as Config>::Currency as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;
 
 /// Index used to access chunks.
 type SetIndex = u32;
@@ -152,8 +152,8 @@ type ApprovalFlag = u32;
 /// Number of approval flags that can fit into [`ApprovalFlag`] type.
 const APPROVAL_FLAG_LEN: usize = 32;
 
-pub trait Trait: frame_system::Trait {
-	type Event: From<Event<Self>> + Into<<Self as frame_system::Trait>::Event>;
+pub trait Config: frame_system::Config {
+	type Event: From<Event<Self>> + Into<<Self as frame_system::Config>::Event>;
 
 	/// Identifier for the elections pallet's lock
 	type ModuleId: Get<LockIdentifier>;
@@ -218,7 +218,7 @@ pub trait Trait: frame_system::Trait {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Elections {
+	trait Store for Module<T: Config> as Elections {
 		// ---- parameters
 
 		/// How long to give each top candidate to present themselves after the vote ends.
@@ -286,7 +286,7 @@ decl_storage! {
 
 decl_error! {
 	/// Error for the elections module.
-	pub enum Error for Module<T: Trait> {
+	pub enum Error for Module<T: Config> {
 		/// Reporter must be a voter.
 		NotVoter,
 		/// Target for inactivity cleanup must be active.
@@ -345,7 +345,7 @@ decl_error! {
 }
 
 decl_module! {
-	pub struct Module<T: Trait> for enum Call where origin: T::Origin {
+	pub struct Module<T: Config> for enum Call where origin: T::Origin {
 		type Error = Error<T>;
 
 		/// How much should be locked up in order to submit one's candidacy. A reasonable
@@ -706,7 +706,7 @@ decl_module! {
 }
 
 decl_event!(
-	pub enum Event<T> where <T as frame_system::Trait>::AccountId {
+	pub enum Event<T> where <T as frame_system::Config>::AccountId {
 		/// Reaped \[voter, reaper\].
 		VoterReaped(AccountId, AccountId),
 		/// Slashed \[reaper\].
@@ -719,7 +719,7 @@ decl_event!(
 	}
 );
 
-impl<T: Trait> Module<T> {
+impl<T: Config> Module<T> {
 	// exposed immutables.
 
 	/// True if we're currently in a presentation period.

substrate/frame/elections/src/mock.rs

@@ -37,7 +37,7 @@ parameter_types! {
 	pub const MaximumBlockLength: u32 = 2 * 1024;
 	pub const AvailableBlockRatio: Perbill = Perbill::one();
 }
-impl frame_system::Trait for Test {
+impl frame_system::Config for Test {
 	type BaseCallFilter = ();
 	type Origin = Origin;
 	type Call = Call;
@@ -68,7 +68,7 @@ impl frame_system::Trait for Test {
 parameter_types! {
 	pub const ExistentialDeposit: u64 = 1;
 }
-impl pallet_balances::Trait for Test {
+impl pallet_balances::Config for Test {
 	type MaxLocks = ();
 	type Balance = u64;
 	type DustRemoval = ();
@@ -110,7 +110,7 @@ parameter_types!{
 	pub const ElectionModuleId: LockIdentifier = *b"py/elect";
 }
 
-impl elections::Trait for Test {
+impl elections::Config for Test {
 	type Event = Event;
 	type Currency = Balances;
 	type BadPresentation = ();

substrate/frame/elections/src/tests.rs

@@ -680,8 +680,8 @@ fn retracting_active_voter_should_slash_reporter() {
 		assert_ok!(Elections::end_block(System::block_number()));
 
 		assert_eq!(Elections::vote_index(), 2);
-		assert_eq!(<Test as Trait>::InactiveGracePeriod::get(), 1);
-		assert_eq!(<Test as Trait>::VotingPeriod::get(), 4);
+		assert_eq!(<Test as Config>::InactiveGracePeriod::get(), 1);
+		assert_eq!(<Test as Config>::VotingPeriod::get(), 4);
 		assert_eq!(Elections::voter_info(4), Some(VoterInfo { last_win: 1, last_active: 0, stake: 40, pot: 0 }));
 
 		assert_ok!(Elections::reap_inactive_voter(Origin::signed(4),