Rename pallet trait Trait to Config (#7599)

* rename Trait to Config

* add test asserting using Trait is still valid.

* fix ui tests

substrate/frame/session/src/historical/mod.rs

@@ -41,8 +41,8 @@ mod shared;
 pub mod offchain;
 pub mod onchain;
 
-/// Trait necessary for the historical module.
-pub trait Trait: super::Trait {
+/// Config necessary for the historical module.
+pub trait Config: super::Config {
 	/// Full identification of the validator.
 	type FullIdentification: Parameter;
 
@@ -57,7 +57,7 @@ pub trait Trait: super::Trait {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Session {
+	trait Store for Module<T: Config> as Session {
 		/// Mapping from historical session indices to session-data root hash and validator count.
 		HistoricalSessions get(fn historical_root):
 			map hasher(twox_64_concat) SessionIndex => Option<(T::Hash, ValidatorCount)>;
@@ -71,10 +71,10 @@ decl_storage! {
 }
 
 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 {}
 }
 
-impl<T: Trait> Module<T> {
+impl<T: Config> Module<T> {
 	/// Prune historical stored session roots up to (but not including)
 	/// `up_to`.
 	pub fn prune_up_to(up_to: SessionIndex) {
@@ -116,7 +116,7 @@ pub trait SessionManager<ValidatorId, FullIdentification>: crate::SessionManager
 /// sets the historical trie root of the ending session.
 pub struct NoteHistoricalRoot<T, I>(sp_std::marker::PhantomData<(T, I)>);
 
-impl<T: Trait, I> crate::SessionManager<T::ValidatorId> for NoteHistoricalRoot<T, I>
+impl<T: Config, I> crate::SessionManager<T::ValidatorId> for NoteHistoricalRoot<T, I>
 	where I: SessionManager<T::ValidatorId, T::FullIdentification>
 {
 	fn new_session(new_index: SessionIndex) -> Option<Vec<T::ValidatorId>> {
@@ -160,15 +160,15 @@ impl<T: Trait, I> crate::SessionManager<T::ValidatorId> for NoteHistoricalRoot<T
 }
 
 /// A tuple of the validator's ID and their full identification.
-pub type IdentificationTuple<T> = (<T as crate::Trait>::ValidatorId, <T as Trait>::FullIdentification);
+pub type IdentificationTuple<T> = (<T as crate::Config>::ValidatorId, <T as Config>::FullIdentification);
 
 /// A trie instance for checking and generating proofs.
-pub struct ProvingTrie<T: Trait> {
+pub struct ProvingTrie<T: Config> {
 	db: MemoryDB<T::Hashing>,
 	root: T::Hash,
 }
 
-impl<T: Trait> ProvingTrie<T> {
+impl<T: Config> ProvingTrie<T> {
 	fn generate_for<I>(validators: I) -> Result<Self, &'static str>
 		where I: IntoIterator<Item=(T::ValidatorId, T::FullIdentification)>
 	{
@@ -260,7 +260,7 @@ impl<T: Trait> ProvingTrie<T> {
 	}
 }
 
-impl<T: Trait, D: AsRef<[u8]>> frame_support::traits::KeyOwnerProofSystem<(KeyTypeId, D)>
+impl<T: Config, D: AsRef<[u8]>> frame_support::traits::KeyOwnerProofSystem<(KeyTypeId, D)>
 	for Module<T>
 {
 	type Proof = MembershipProof;

substrate/frame/session/src/historical/offchain.rs

@@ -29,18 +29,18 @@ use sp_runtime::{offchain::storage::StorageValueRef, KeyTypeId};
 use sp_session::MembershipProof;
 
 use super::super::{Module as SessionModule, SessionIndex};
-use super::{IdentificationTuple, ProvingTrie, Trait};
+use super::{IdentificationTuple, ProvingTrie, Config};
 
 use super::shared;
 use sp_std::prelude::*;
 
 
 /// A set of validators, which was used for a fixed session index.
-struct ValidatorSet<T: Trait> {
+struct ValidatorSet<T: Config> {
 	validator_set: Vec<IdentificationTuple<T>>,
 }
 
-impl<T: Trait> ValidatorSet<T> {
+impl<T: Config> ValidatorSet<T> {
 	/// Load the set of validators for a particular session index from the off-chain storage.
 	///
 	/// If none is found or decodable given `prefix` and `session`, it will return `None`.
@@ -61,7 +61,7 @@ impl<T: Trait> ValidatorSet<T> {
 
 /// Implement conversion into iterator for usage
 /// with [ProvingTrie](super::ProvingTrie::generate_for).
-impl<T: Trait> sp_std::iter::IntoIterator for ValidatorSet<T> {
+impl<T: Config> sp_std::iter::IntoIterator for ValidatorSet<T> {
 	type Item = (T::ValidatorId, T::FullIdentification);
 	type IntoIter = sp_std::vec::IntoIter<Self::Item>;
 	fn into_iter(self) -> Self::IntoIter {
@@ -74,7 +74,7 @@ impl<T: Trait> sp_std::iter::IntoIterator for ValidatorSet<T> {
 /// Based on the yielded `MembershipProof` the implementer may decide what
 /// to do, i.e. in case of a failed proof, enqueue a transaction back on
 /// chain reflecting that, with all its consequences such as i.e. slashing.
-pub fn prove_session_membership<T: Trait, D: AsRef<[u8]>>(
+pub fn prove_session_membership<T: Config, D: AsRef<[u8]>>(
 	session_index: SessionIndex,
 	session_key: (KeyTypeId, D),
 ) -> Option<MembershipProof> {
@@ -97,7 +97,7 @@ pub fn prove_session_membership<T: Trait, D: AsRef<[u8]>>(
 /// Due to re-organisation it could be that the `first_to_keep` might be less
 /// than the stored one, in which case the conservative choice is made to keep records
 /// up to the one that is the lesser.
-pub fn prune_older_than<T: Trait>(first_to_keep: SessionIndex) {
+pub fn prune_older_than<T: Config>(first_to_keep: SessionIndex) {
 	let derived_key = shared::LAST_PRUNE.to_vec();
 	let entry = StorageValueRef::persistent(derived_key.as_ref());
 	match entry.mutate(|current: Option<Option<SessionIndex>>| -> Result<_, ()> {
@@ -127,7 +127,7 @@ pub fn prune_older_than<T: Trait>(first_to_keep: SessionIndex) {
 }
 
 /// Keep the newest `n` items, and prune all items older than that.
-pub fn keep_newest<T: Trait>(n_to_keep: usize) {
+pub fn keep_newest<T: Config>(n_to_keep: usize) {
 	let session_index = <SessionModule<T>>::current_index();
 	let n_to_keep = n_to_keep as SessionIndex;
 	if n_to_keep < session_index {
@@ -189,8 +189,8 @@ mod tests {
 	#[test]
 	fn encode_decode_roundtrip() {
 		use codec::{Decode, Encode};
-		use super::super::super::Trait as SessionTrait;
-		use super::super::Trait as HistoricalTrait;
+		use super::super::super::Config as SessionTrait;
+		use super::super::Config as HistoricalTrait;
 
 		let sample = (
 				22u32 as <Test as SessionTrait>::ValidatorId,

substrate/frame/session/src/historical/onchain.rs

@@ -20,9 +20,9 @@
 use codec::Encode;
 use sp_runtime::traits::Convert;
 
-use super::super::Trait as SessionTrait;
+use super::super::Config as SessionTrait;
 use super::super::{Module as SessionModule, SessionIndex};
-use super::Trait as HistoricalTrait;
+use super::Config as HistoricalTrait;
 
 use super::shared;
 use sp_std::prelude::*;