Add local cluster test for forwarding

core/src/cluster_tests.rs

@@ -48,6 +48,27 @@ pub fn spend_and_verify_all_nodes(
     }
 }
 
+pub fn send_many_transactions(node: &ContactInfo, funding_keypair: &Keypair, num_txs: u64) {
+    let mut client = mk_client(node);
+    for _ in 0..num_txs {
+        let random_keypair = Keypair::new();
+        let bal = client
+            .poll_get_balance(&funding_keypair.pubkey())
+            .expect("balance in source");
+        assert!(bal > 0);
+        let mut transaction = SystemTransaction::new_move(
+            &funding_keypair,
+            random_keypair.pubkey(),
+            1,
+            client.get_recent_blockhash(),
+            0,
+        );
+        client
+            .retry_transfer(&funding_keypair, &mut transaction, 5)
+            .unwrap();
+    }
+}
+
 pub fn fullnode_exit(entry_point_info: &ContactInfo, nodes: usize) {
     let cluster_nodes = discover(&entry_point_info.gossip, nodes).unwrap();
     assert!(cluster_nodes.len() >= nodes);

tests/local_cluster.rs

@@ -2,6 +2,7 @@ extern crate solana;
 
 use solana::cluster_tests;
 use solana::fullnode::FullnodeConfig;
+use solana::gossip_service::discover;
 use solana::local_cluster::LocalCluster;
 use solana::poh_service::PohServiceConfig;
 use solana_sdk::timing::{DEFAULT_SLOTS_PER_EPOCH, DEFAULT_TICKS_PER_SLOT};
@@ -109,3 +110,21 @@ fn test_two_unbalanced_stakes() {
 
     drop(cluster);
 }
+
+#[test]
+fn test_forwarding() {
+    // Set up a cluster where one node is never the leader, so all txs sent to this node
+    // will be have to be forwarded
+    let fullnode_config = FullnodeConfig::default();
+    let cluster = LocalCluster::new_with_config(&[999_990, 3], 2_000_000, &fullnode_config);
+
+    let cluster_nodes = discover(&cluster.entry_point_info.gossip, 2).unwrap();
+    assert!(cluster_nodes.len() >= 2);
+
+    let leader_id = cluster.entry_point_info.id;
+
+    let validator_info = cluster_nodes.iter().find(|c| c.id != leader_id).unwrap();
+    cluster_tests::send_many_transactions(&validator_info, &cluster.funding_keypair, 20);
+
+    drop(cluster);
+}