Add threshold > 0 guard and FSM transition test for FinalizedStateNotAvailable

Author: Krish-vemula

multinode/node_fsm_test.go

@@ -86,6 +86,13 @@ func TestUnit_Node_StateTransitions(t *testing.T) {
 			node.transitionToSyncing(fn.Fn)
 		})
 	})
+	t.Run("transitionToFinalizedStateNotAvailable", func(t *testing.T) {
+		const destinationState = nodeStateFinalizedStateNotAvailable
+		allowedStates := []nodeState{nodeStateAlive}
+		rpc := newMockRPCClient[ID, Head](t)
+		rpc.On("Close")
+		testTransition(t, rpc, testNode.transitionToFinalizedStateNotAvailable, destinationState, allowedStates...)
+	})
 }
 
 func testTransition(t *testing.T, rpc *mockRPCClient[ID, Head], transition func(node testNode, fn func()), destinationState nodeState, allowedStates ...nodeState) {

multinode/node_lifecycle.go

@@ -161,7 +161,7 @@ func (n *node[CHAIN_ID, HEAD, RPC]) aliveLoop() {
 						finalizedStateFailures++
 					}
 					lggr.Warnw("Finalized state not available", "err", stateErr, "failures", finalizedStateFailures, "threshold", finalizedStateCheckFailureThreshold)
-					if finalizedStateFailures >= finalizedStateCheckFailureThreshold {
+					if finalizedStateCheckFailureThreshold > 0 && finalizedStateFailures >= finalizedStateCheckFailureThreshold {
 						lggr.Errorw("RPC node cannot serve finalized state after consecutive failures", "failures", finalizedStateFailures)
 						if n.poolInfoProvider != nil {
 							if l, _ := n.poolInfoProvider.LatestChainInfo(); l < 2 && !n.isLoadBalancedRPC {