migration

toolkit/pallets/session-validator-management/src/migrations/v1.rs

@@ -1,8 +1,10 @@
 #[cfg(feature = "try-runtime")]
 extern crate alloc;
+use crate::CommitteeMemberInfo;
 #[cfg(feature = "try-runtime")]
 use alloc::vec::Vec;
 use frame_support::traits::UncheckedOnRuntimeUpgrade;
+use parity_scale_codec::Encode;
 
 mod v0 {
 	use frame_support::pallet_prelude::OptionQuery;
@@ -110,11 +112,74 @@ where
 
 	#[cfg(feature = "try-runtime")]
 	fn pre_upgrade() -> Result<Vec<u8>, sp_runtime::TryRuntimeError> {
-		Ok(vec![])
+		let current_committee_v0 = v0::CurrentCommittee::<T>::get();
+		let next_committee_v0 = v0::NextCommittee::<T>::get();
+		Ok((current_committee_v0, next_committee_v0).encode())
 	}
 
 	#[cfg(feature = "try-runtime")]
-	fn post_upgrade(_state: Vec<u8>) -> Result<(), sp_runtime::TryRuntimeError> {
+	fn post_upgrade(state: Vec<u8>) -> Result<(), sp_runtime::TryRuntimeError> {
+		use frame_support::ensure;
+		use parity_scale_codec::Decode;
+		use v0::LegacyCommitteeInfo;
+
+		let (current_committee_v0, next_committee_v0): (
+			LegacyCommitteeInfo<
+				T::ScEpochNumber,
+				T::AuthorityId,
+				T::AuthorityKeys,
+				T::MaxValidators,
+			>,
+			Option<
+				LegacyCommitteeInfo<
+					T::ScEpochNumber,
+					T::AuthorityId,
+					T::AuthorityKeys,
+					T::MaxValidators,
+				>,
+			>,
+		) = Decode::decode(&mut state.as_slice())
+			.expect("Previously encoded state should be decodable");
+
+		let current_committee_v1 = crate::CurrentCommittee::<T>::get();
+		let next_committee_v1 = crate::NextCommittee::<T>::get();
+
+		ensure!(
+			current_committee_v0.epoch == current_committee_v1.epoch,
+			"current epoch should be preserved"
+		);
+
+		ensure!(
+			current_committee_v0.committee.to_vec()
+				== (current_committee_v1.committee.iter())
+					.map(|member| (member.authority_id(), member.authority_keys()))
+					.collect::<Vec<_>>(),
+			"current committee membership should be preserved"
+		);
+
+		if next_committee_v0.is_none() && next_committee_v0.is_none() {
+			return Ok(());
+		}
+
+		ensure!(next_committee_v0.is_some(), "V0 next committee should be Some if V1 is");
+		ensure!(next_committee_v1.is_some(), "V1 next committee should be Some if V0 is");
+
+		let next_committee_v0 = next_committee_v0.unwrap();
+		let next_committee_v1 = next_committee_v1.unwrap();
+
+		ensure!(
+			next_committee_v0.epoch == next_committee_v1.epoch,
+			"next epoch should be preserved"
+		);
+
+		ensure!(
+			next_committee_v0.committee.to_vec()
+				== (next_committee_v1.committee.iter())
+					.map(|member| (member.authority_id(), member.authority_keys()))
+					.collect::<Vec<_>>(),
+			"next committee membership should be preserved"
+		);
+
 		Ok(())
 	}
 }