Rewrite fork tree functions using loops.

client/consensus/epochs/src/lib.rs

@@ -312,7 +312,7 @@ fn fake_head_hash<H: AsRef<[u8]> + AsMut<[u8]> + Clone>(parent_hash: &H) -> H {
 }
 
 impl<Hash, Number, E: Epoch> Default for EpochChanges<Hash, Number, E> where
-	Hash: PartialEq + Ord,
+	Hash: Eq + Ord + Clone + std::hash::Hash,
 	Number: Ord,
 {
 	fn default() -> Self {
@@ -321,7 +321,7 @@ impl<Hash, Number, E: Epoch> Default for EpochChanges<Hash, Number, E> where
 }
 
 impl<Hash, Number, E: Epoch> EpochChanges<Hash, Number, E> where
-	Hash: PartialEq + Ord + AsRef<[u8]> + AsMut<[u8]> + Copy,
+	Hash: Eq + Ord + AsRef<[u8]> + AsMut<[u8]> + Copy + std::hash::Hash,
 	Number: Ord + One + Zero + Add<Output=Number> + Copy,
 {
 	/// Create a new epoch change.

client/consensus/epochs/src/migration.rs

@@ -32,7 +32,7 @@ pub struct EpochChangesV0<Hash, Number, E: Epoch> {
 pub type EpochChangesForV0<Block, Epoch> = EpochChangesV0<<Block as BlockT>::Hash, NumberFor<Block>, Epoch>;
 
 impl<Hash, Number, E: Epoch> EpochChangesV0<Hash, Number, E> where
-	Hash: PartialEq + Ord + Copy,
+	Hash: Eq + Ord + Copy + std::hash::Hash,
 	Number: Ord + Copy,
 {
 	/// Create a new value of this type from raw.

client/finality-grandpa/rpc/src/report.rs

@@ -20,6 +20,7 @@ use std::{
 	collections::{BTreeSet, HashSet},
 	fmt::Debug,
 	ops::Add,
+	hash::Hash,
 };
 
 use serde::{Deserialize, Serialize};
@@ -41,7 +42,7 @@ pub trait ReportVoterState {
 impl<H, N> ReportAuthoritySet for SharedAuthoritySet<H, N>
 where
 	N: Add<Output = N> + Ord + Clone + Debug,
-	H: Clone + Debug + Eq,
+	H: Clone + Debug + Eq + Hash,
 {
 	fn get(&self) -> (u64, HashSet<AuthorityId>) {
 		let current_voters: HashSet<AuthorityId> = self

client/finality-grandpa/src/authorities.rs

@@ -30,6 +30,7 @@ use std::cmp::Ord;
 use std::fmt::Debug;
 use std::ops::Add;
 use std::sync::Arc;
+use std::hash::Hash;
 
 /// Error type returned on operations on the `AuthoritySet`.
 #[derive(Debug, derive_more::Display)]
@@ -88,7 +89,7 @@ impl<H, N> SharedAuthoritySet<H, N> {
 
 impl<H: Eq, N> SharedAuthoritySet<H, N>
 where N: Add<Output=N> + Ord + Clone + Debug,
-	  H: Clone + Debug
+	  H: Clone + Debug + Hash,
 {
 	/// Get the earliest limit-block number that's higher or equal to the given
 	/// min number, if any.
@@ -156,7 +157,7 @@ pub struct AuthoritySet<H, N> {
 
 impl<H, N> AuthoritySet<H, N>
 where
-	H: PartialEq,
+	H: Eq + Hash + Clone,
 	N: Ord,
 {
 	// authority sets must be non-empty and all weights must be greater than 0
@@ -206,7 +207,7 @@ where
 impl<H: Eq, N> AuthoritySet<H, N>
 where
 	N: Add<Output = N> + Ord + Clone + Debug,
-	H: Clone + Debug,
+	H: Clone + Debug + Hash,
 {
 	/// Returns the block hash and height at which the next pending change in
 	/// the given chain (i.e. it includes `best_hash`) was signalled, `None` if
@@ -793,8 +794,8 @@ mod tests {
 			delay_kind: DelayKind::Finalized,
 		};
 
-		authorities.add_pending_change(change_a.clone(), &static_is_descendent_of(true)).unwrap();
-		authorities.add_pending_change(change_b.clone(), &static_is_descendent_of(true)).unwrap();
+		authorities.add_pending_change(change_a.clone(), &static_is_descendent_of(false)).unwrap();
+		authorities.add_pending_change(change_b.clone(), &static_is_descendent_of(false)).unwrap();
 
 		assert_eq!(
 			authorities.pending_changes().collect::<Vec<_>>(),

client/finality-grandpa/src/aux_schema.rs

@@ -18,6 +18,7 @@
 
 use std::fmt::Debug;
 use std::sync::Arc;
+use std::hash::Hash;
 use parity_scale_codec::{Encode, Decode};
 use sc_client_api::backend::AuxStore;
 use sp_blockchain::{Result as ClientResult, Error as ClientError};
@@ -70,7 +71,7 @@ struct V0AuthoritySet<H, N> {
 }
 
 impl<H, N> Into<AuthoritySet<H, N>> for V0AuthoritySet<H, N>
-where H: Clone + Debug + PartialEq,
+where H: Clone + Debug + Eq + Hash,
 	  N: Clone + Debug + Ord,
 {
 	fn into(self) -> AuthoritySet<H, N> {