Wait for RPC readiness before running test setup

The wait_for_ready check only verified P2P port connectivity. Dashd can
accept P2P connections while RPC still returns code -28 (initializing).
Now also polls get_blockchain_info until it succeeds.

Author: xdustinface

dash-spv/src/test_utils/node.rs

@@ -200,10 +200,32 @@ impl DashCoreNode {
         let check_interval = Duration::from_millis(500);
 
         let result = timeout(max_wait, async {
+            // Wait for the P2P port to accept connections
             loop {
                 let addr = SocketAddr::from((Ipv4Addr::new(127, 0, 0, 1), self.config.p2p_port));
                 if tokio::net::TcpStream::connect(addr).await.is_ok() {
-                    return true;
+                    break;
+                }
+                sleep(check_interval).await;
+            }
+
+            // Wait for RPC to be fully responsive (not just "warming up")
+            loop {
+                let url = format!("http://127.0.0.1:{}", self.config.rpc_port);
+                let cookie_path = self.config.datadir.join("regtest/.cookie");
+                if let Ok(auth) = cookie_path
+                    .exists()
+                    .then(|| Auth::CookieFile(cookie_path))
+                    .ok_or(())
+                {
+                    if let Ok(client) = Client::new(&url, auth) {
+                        match client.get_blockchain_info() {
+                            Ok(_) => return true,
+                            Err(e) => {
+                                tracing::debug!("RPC not ready yet: {}", e);
+                            }
+                        }
+                    }
                 }
                 sleep(check_interval).await;
             }