Rename pallet trait Trait to Config (#7599)

* rename Trait to Config

* add test asserting using Trait is still valid.

* fix ui tests

substrate/frame/assets/src/lib.rs

@@ -28,7 +28,7 @@
 //! * Asset Transfer
 //! * Asset Destruction
 //!
-//! To use it in your runtime, you need to implement the assets [`Trait`](./trait.Trait.html).
+//! To use it in your runtime, you need to implement the assets [`Config`](./trait.Config.html).
 //!
 //! The supported dispatchable functions are documented in the [`Call`](./enum.Call.html) enum.
 //!
@@ -89,10 +89,10 @@
 //! use frame_support::{decl_module, dispatch, ensure};
 //! use frame_system::ensure_signed;
 //!
-//! pub trait Trait: assets::Trait { }
+//! pub trait Config: assets::Config { }
 //!
 //! 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 {
 //! 		pub fn issue_token_airdrop(origin) -> dispatch::DispatchResult {
 //! 			let sender = ensure_signed(origin).map_err(|e| e.as_str())?;
 //!
@@ -123,7 +123,7 @@
 //! them are violated, the behavior of this module is undefined.
 //!
 //! * The total count of assets should be less than
-//!   `Trait::AssetId::max_value()`.
+//!   `Config::AssetId::max_value()`.
 //!
 //! ## Related Modules
 //!
@@ -139,9 +139,9 @@ use frame_system::ensure_signed;
 use sp_runtime::traits::One;
 
 /// The module configuration trait.
-pub trait Trait: frame_system::Trait {
+pub trait Config: frame_system::Config {
 	/// The overarching event type.
-	type Event: From<Event<Self>> + Into<<Self as frame_system::Trait>::Event>;
+	type Event: From<Event<Self>> + Into<<Self as frame_system::Config>::Event>;
 
 	/// The units in which we record balances.
 	type Balance: Member + Parameter + AtLeast32BitUnsigned + Default + Copy;
@@ -151,7 +151,7 @@ pub trait Trait: frame_system::Trait {
 }
 
 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>;
 
 		fn deposit_event() = default;
@@ -226,9 +226,9 @@ decl_module! {
 
 decl_event! {
 	pub enum Event<T> where
-		<T as frame_system::Trait>::AccountId,
-		<T as Trait>::Balance,
-		<T as Trait>::AssetId,
+		<T as frame_system::Config>::AccountId,
+		<T as Config>::Balance,
+		<T as Config>::AssetId,
 	{
 		/// Some assets were issued. \[asset_id, owner, total_supply\]
 		Issued(AssetId, AccountId, Balance),
@@ -240,7 +240,7 @@ decl_event! {
 }
 
 decl_error! {
-	pub enum Error for Module<T: Trait> {
+	pub enum Error for Module<T: Config> {
 		/// Transfer amount should be non-zero
 		AmountZero,
 		/// Account balance must be greater than or equal to the transfer amount
@@ -251,7 +251,7 @@ decl_error! {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Assets {
+	trait Store for Module<T: Config> as Assets {
 		/// The number of units of assets held by any given account.
 		Balances: map hasher(blake2_128_concat) (T::AssetId, T::AccountId) => T::Balance;
 		/// The next asset identifier up for grabs.
@@ -264,7 +264,7 @@ decl_storage! {
 }
 
 // The main implementation block for the module.
-impl<T: Trait> Module<T> {
+impl<T: Config> Module<T> {
 	// Public immutables
 
 	/// Get the asset `id` balance of `who`.
@@ -298,7 +298,7 @@ mod tests {
 		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 Index = u64;
@@ -325,7 +325,7 @@ mod tests {
 		type OnKilledAccount = ();
 		type SystemWeightInfo = ();
 	}
-	impl Trait for Test {
+	impl Config for Test {
 		type Event = ();
 		type Balance = u64;
 		type AssetId = u32;