From 0b0f42f583f3a616a88afe45fcd06d31e7d9a06f Mon Sep 17 00:00:00 2001
From: Nikhil Gupta <17176722+gupnik@users.noreply.github.com>
Date: Tue, 11 Jul 2023 18:48:55 +0530
Subject: [PATCH] Fixes trait bounds

---
 bridges/primitives/header-chain/Cargo.toml           | 1 +
 bridges/primitives/header-chain/src/justification.rs | 4 +++-
 bridges/primitives/header-chain/src/lib.rs           | 7 ++++---
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/bridges/primitives/header-chain/Cargo.toml b/bridges/primitives/header-chain/Cargo.toml
index 962d262d571..d471908cf9c 100644
--- a/bridges/primitives/header-chain/Cargo.toml
+++ b/bridges/primitives/header-chain/Cargo.toml
@@ -9,6 +9,7 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 [dependencies]
 codec = { package = "parity-scale-codec", version = "3.1.5", default-features = false }
 finality-grandpa = { version = "0.16.2", default-features = false }
+num-traits = { version = "0.2", default-features = false }
 scale-info = { version = "2.9.0", default-features = false, features = ["derive"] }
 serde = { version = "1.0", default-features = false, features = ["alloc", "derive"] }
 
diff --git a/bridges/primitives/header-chain/src/justification.rs b/bridges/primitives/header-chain/src/justification.rs
index 9cf4427bccf..2855de7c2ed 100644
--- a/bridges/primitives/header-chain/src/justification.rs
+++ b/bridges/primitives/header-chain/src/justification.rs
@@ -25,9 +25,10 @@ use bp_runtime::{BlockNumberOf, Chain, HashOf};
 use codec::{Decode, Encode, MaxEncodedLen};
 use finality_grandpa::voter_set::VoterSet;
 use frame_support::RuntimeDebug;
+use num_traits::AsPrimitive;
 use scale_info::TypeInfo;
 use sp_consensus_grandpa::{AuthorityId, AuthoritySignature, SetId};
-use sp_runtime::{traits::Header as HeaderT, SaturatedConversion};
+use sp_runtime::{traits::{Block as BlockT, Header as HeaderT}, SaturatedConversion};
 use sp_std::{
 	collections::{btree_map::BTreeMap, btree_set::BTreeSet},
 	prelude::*,
@@ -76,6 +77,7 @@ impl<H: HeaderT> GrandpaJustification<H> {
 	pub fn max_reasonable_size<C>(required_precommits: u32) -> u32
 	where
 		C: Chain + ChainWithGrandpa,
+		<<<C as Chain>::Block as BlockT>::Header as HeaderT>::Number: AsPrimitive<usize>
 	{
 		// we don't need precise results here - just estimations, so some details
 		// are removed from computations (e.g. bytes required to encode vector length)
diff --git a/bridges/primitives/header-chain/src/lib.rs b/bridges/primitives/header-chain/src/lib.rs
index cf08a936234..f75525d7099 100644
--- a/bridges/primitives/header-chain/src/lib.rs
+++ b/bridges/primitives/header-chain/src/lib.rs
@@ -29,8 +29,9 @@ use frame_support::PalletError;
 use scale_info::TypeInfo;
 use serde::{Deserialize, Serialize};
 use sp_consensus_grandpa::{AuthorityList, ConsensusLog, SetId, GRANDPA_ENGINE_ID};
-use sp_runtime::{traits::Header as HeaderT, Digest, RuntimeDebug};
+use sp_runtime::{traits::{Block as BlockT, Header as HeaderT}, Digest, RuntimeDebug};
 use sp_std::boxed::Box;
+use num_traits::AsPrimitive;
 
 pub mod justification;
 pub mod storage_keys;
@@ -69,7 +70,7 @@ impl<H: HeaderT> StoredHeaderDataBuilder<H::Number, H::Hash> for H {
 }
 
 /// Substrate header chain, abstracted from the way it is stored.
-pub trait HeaderChain<C: Chain> {
+pub trait HeaderChain<C: Chain> where <<<C as Chain>::Block as BlockT>::Header as HeaderT>::Number: AsPrimitive<usize> {
 	/// Returns state (storage) root of given finalized header.
 	fn finalized_header_state_root(header_hash: HashOf<C>) -> Option<HashOf<C>>;
 	/// Get storage proof checker using finalized header.
@@ -181,7 +182,7 @@ pub type BridgeGrandpaCallOf<C> = BridgeGrandpaCall<HeaderOf<C>>;
 ///
 /// Keep in mind that parachains are relying on relay chain GRANDPA, so they should not implement
 /// this trait.
-pub trait ChainWithGrandpa: Chain {
+pub trait ChainWithGrandpa: Chain where <<<Self as Chain>::Block as BlockT>::Header as HeaderT>::Number: AsPrimitive<usize> {
 	/// Name of the bridge GRANDPA pallet (used in `construct_runtime` macro call) that is deployed
 	/// at some other chain to bridge with this `ChainWithGrandpa`.
 	///