empty activity for all nodes support (#382)

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pallets/ddc-verification/src/lib.rs

@@ -1400,6 +1400,10 @@ pub mod pallet {
 		pub(crate) fn create_merkle_root(
 			leaves: &[ActivityHash],
 		) -> Result<ActivityHash, OCWError> {
+			if leaves.is_empty() {
+				return Ok(ActivityHash::default());
+			}
+
 			let store = MemStore::default();
 			let mut mmr: MMR<ActivityHash, MergeActivityHash, &MemStore<ActivityHash>> =
 				MemMMR::<_, MergeActivityHash>::new(0, &store);
@@ -1924,10 +1928,17 @@ pub mod pallet {
 				// threshold
 				era_validation.payers_merkle_root_hash = payers_merkle_root_hash;
 				era_validation.payees_merkle_root_hash = payees_merkle_root_hash;
-				era_validation.status = EraValidationStatus::ReadyForPayout;
 				era_validation.start_era = era_activity.start;
 				era_validation.end_era = era_activity.end;
 
+				if payers_merkle_root_hash == ActivityHash::default() &&
+					payees_merkle_root_hash == payers_merkle_root_hash
+				{
+					era_validation.status = EraValidationStatus::PayoutSuccess;
+				} else {
+					era_validation.status = EraValidationStatus::ReadyForPayout;
+				}
+
 				should_deposit_ready_event = true;
 			}
 

pallets/ddc-verification/src/tests.rs

@@ -583,6 +583,35 @@ fn test_get_consensus_nodes_activity_success() {
 	assert_eq!(consensus_activities[0].stored_bytes, 100);
 }
 
+#[test]
+fn test_get_consensus_customers_activity_empty() {
+	let cluster_id = ClusterId::from([1; 20]);
+	let era_id = 1;
+	let min_nodes = 3;
+	let threshold = Percent::from_percent(67);
+
+	let node_pubkey_0 = NodePubKey::StoragePubKey(AccountId32::new([0; 32]));
+	let node_pubkey_1 = NodePubKey::StoragePubKey(AccountId32::new([1; 32]));
+	let node_pubkey_2 = NodePubKey::StoragePubKey(AccountId32::new([2; 32]));
+
+	let customers_activity = vec![
+		(node_pubkey_0.clone(), Vec::<CustomerActivity>::new()),
+		(node_pubkey_1.clone(), Vec::<CustomerActivity>::new()),
+		(node_pubkey_2.clone(), Vec::<CustomerActivity>::new()),
+	];
+
+	let result = DdcVerification::get_consensus_for_activities(
+		&cluster_id,
+		era_id,
+		&customers_activity,
+		min_nodes,
+		threshold,
+	);
+	assert!(result.is_ok());
+	let consensus_activities = result.unwrap();
+	assert_eq!(consensus_activities.len(), 0);
+}
+
 #[test]
 fn test_get_consensus_customers_activity_not_enough_nodes() {
 	let cluster_id1 = ClusterId::from([1; 20]);
@@ -1055,6 +1084,15 @@ fn test_convert_to_batch_merkle_roots() {
 	assert_eq!(result_roots, expected_roots);
 }
 
+#[test]
+fn test_convert_to_batch_merkle_roots_empty() {
+	let result_roots =
+		DdcVerification::convert_to_batch_merkle_roots(Vec::<Vec<NodeActivity>>::new()).unwrap();
+	let expected_roots: Vec<ActivityHash> = Vec::<ActivityHash>::new();
+
+	assert_eq!(result_roots, expected_roots);
+}
+
 #[test]
 fn test_split_to_batches_empty_activities() {
 	let activities: Vec<NodeActivity> = vec![];
@@ -1655,6 +1693,16 @@ fn create_merkle_root_works() {
 	});
 }
 
+#[test]
+fn create_merkle_root_empty() {
+	new_test_ext().execute_with(|| {
+		let leaves = Vec::<ActivityHash>::new();
+		let root = DdcVerification::create_merkle_root(&leaves).unwrap();
+
+		assert_eq!(root, ActivityHash::default());
+	});
+}
+
 #[test]
 fn proof_merkle_leaf_works() {
 	new_test_ext().execute_with(|| {