Keep queued startup control input ordered

src/bin/dosh-client.rs

@@ -2904,8 +2904,11 @@ async fn run_terminal(
                             if let Some(deadline) = startup_input_hold_until {
                                 if !predictor.alternate_screen
                                     && Instant::now() < deadline
-                                    && (hold_all_startup_input
+                                    && should_hold_during_startup_gate(
-                                        || should_hold_post_submit_input(&bytes))
+                                        hold_all_startup_input,
+                                        !pending_user_input.is_empty(),
+                                        &bytes,
+                                    )
                                 {
                                     queue_pending_user_input(
                                         &mut pending_user_input,
@@ -3843,6 +3846,10 @@ fn should_hold_post_submit_input(bytes: &[u8]) -> bool {
     matches!(bytes.first(), Some(0x1b | 0x9b))
 }
 
+fn should_hold_during_startup_gate(hold_all: bool, already_queued: bool, bytes: &[u8]) -> bool {
+    hold_all || already_queued || should_hold_post_submit_input(bytes)
+}
+
 async fn flush_pending_user_input(
     socket: &UdpSocket,
     addr: SocketAddr,
@@ -5313,9 +5320,9 @@ mod tests {
         queue_pending_user_input, raw_contains_host_table, recv_response_until,
         render_status_clear, render_status_overlay, requested_env, resolved_startup_command,
         rewrite_forward_command, selected_predict_mode, selected_udp_host, server_version_mismatch,
-        should_hold_post_submit_input, split_after_command_submit, ssh_destination_host,
+        should_hold_during_startup_gate, should_hold_post_submit_input, split_after_command_submit,
-        ssh_username, ssh_with_user, startup_command, status_ssh_target, toml_bare_key_or_quoted,
+        ssh_destination_host, ssh_username, ssh_with_user, startup_command, status_ssh_target,
-        update_check_requested, valid_forward_host,
+        toml_bare_key_or_quoted, update_check_requested, valid_forward_host,
     };
     use dosh::config::{ClientConfig, CommandExtension, HostConfig};
     use dosh::native::EnvVar;
@@ -5988,6 +5995,14 @@ mod tests {
         assert!(!should_hold_post_submit_input(b""));
     }
 
+    #[test]
+    fn startup_gate_keeps_later_input_behind_queued_control_input() {
+        assert!(should_hold_during_startup_gate(false, false, b"\x1b[B"));
+        assert!(should_hold_during_startup_gate(false, true, b"x"));
+        assert!(should_hold_during_startup_gate(true, false, b"x"));
+        assert!(!should_hold_during_startup_gate(false, false, b"x"));
+    }
+
     #[test]
     fn update_check_accepts_only_check_flag() {
         assert!(!update_check_requested(&[]).unwrap());