test(daemon): reattach after disconnect repaints prior output from snapshot

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/spaceshd/src/server.rs

@@ -398,4 +398,37 @@ mod tests {
         }
         panic!("socket never came up");
     }
+
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn reattach_returns_snapshot_with_prior_output() {
+        let dir = tempdir_path();
+        let sock = dir.join("sock");
+        let sock_for_task = sock.clone();
+        tokio::spawn(async move { let _ = serve(&sock_for_task).await; });
+        wait_for_socket(&sock).await;
+
+        // First client: open, new surface that prints a marker, attach, then disconnect.
+        let surface_id;
+        {
+            let mut s = UnixStream::connect(&sock).await.unwrap();
+            let r = req(&mut s, 1, Cmd::Open { path: std::env::temp_dir().to_string_lossy().into() }).await;
+            let ws = res_data(&r)["workspace_id"].as_str().unwrap().to_string();
+            let r = req(&mut s, 2, Cmd::NewSurface {
+                workspace_id: spacesh_proto::WorkspaceId(ws),
+                command: Some("/bin/sh".into()),
+                args: vec!["-c".into(), "printf REPAINT_ME; sleep 2".into()],
+                cols: 80, rows: 24,
+            }).await;
+            surface_id = spacesh_proto::SurfaceId(res_data(&r)["surface_id"].as_str().unwrap().to_string());
+            // Give the actor time to flush output into the grid.
+            tokio::time::sleep(tokio::time::Duration::from_millis(300)).await;
+            // disconnect by dropping `s`
+        }
+
+        // Second client: attach to the same surface, expect snapshot to contain the marker.
+        let mut s2 = UnixStream::connect(&sock).await.unwrap();
+        let r = req(&mut s2, 1, Cmd::Attach { surface_id: surface_id.clone() }).await;
+        let snap = res_data(&r)["snapshot"].as_str().unwrap();
+        assert!(snap.contains("REPAINT_ME"), "snapshot was: {snap:?}");
+    }
 }