Agent: offer Open folder only for a project on this computer

apps/maple-agent/app/src/backend.rs

@@ -303,6 +303,14 @@ impl AgentBackend {
         }
     }
 
+    /// A UI test backend that reports itself as connected to `peer`.
+    #[cfg(test)]
+    pub fn remote_for_test(peer: &str) -> Result<Self, String> {
+        let mut backend = Self::for_test("http://127.0.0.1:9".into(), String::new())?;
+        backend.remote_host = Some(peer.to_string());
+        Ok(backend)
+    }
+
     pub fn new(api_url: String, _harness_instructions: String) -> Result<Self, String> {
         let api_url = maple_agent::maple_api::validate_api_url(&api_url)?;
         let runtime = Runtime::new().map_err(|e| format!("Could not start host client: {e}"))?;

apps/maple-agent/app/src/ui/chat/sidebar.rs

@@ -2023,14 +2023,18 @@ impl Sidebar {
         if target.computer.as_deref() != self.backend.remote_host() {
             return items;
         }
-        let open_root = root.clone();
         let remove_root = root.clone();
-        items.push(SidebarMenuItem {
-            id: target.element_id("open-project"),
-            icon: "folder-open",
-            label: "Open folder",
-            on_click: Box::new(move |this, cx| this.open_folder(&open_root, cx)),
-        });
+        // The file manager runs on this computer, so a paired computer's
+        // folder cannot be revealed from here.
+        if self.backend.remote_host().is_none() {
+            let open_root = root.clone();
+            items.push(SidebarMenuItem {
+                id: target.element_id("open-project"),
+                icon: "folder-open",
+                label: "Open folder",
+                on_click: Box::new(move |this, cx| this.open_folder(&open_root, cx)),
+            });
+        }
         if let Some(status) = self
             .menu_trust
             .as_ref()

apps/maple-agent/app/src/ui/chat/tests.rs

@@ -6333,6 +6333,40 @@ mod state_tests {
             );
         });
     }
+    /// The file manager runs on this computer: a project on a paired
+    /// computer never offers "Open folder", even while that computer is
+    /// the active one.
+    #[gpui::test]
+    fn only_a_local_project_offers_open_folder(cx: &mut TestAppContext) {
+        cx.executor().allow_parking();
+        for (backend, computer) in [
+            (
+                crate::backend::AgentBackend::for_test("http://127.0.0.1:9".into(), String::new()),
+                None,
+            ),
+            (
+                crate::backend::AgentBackend::remote_for_test("east"),
+                Some("east"),
+            ),
+        ] {
+            let backend = Arc::new(backend.expect("backend"));
+            let chat = cx.new(|cx| {
+                let _guard = SETTINGS_LOCK.lock();
+                ChatScreen::new_without_start(backend, "user".to_string(), cx)
+            });
+            chat.update(cx, |this, cx| {
+                let menu = this
+                    .sidebar
+                    .read(cx)
+                    .project_menu_labels_for_test(&ProjectTarget {
+                        computer: computer.map(str::to_string),
+                        path: "/shared".into(),
+                    });
+                assert_eq!(menu.contains(&"Open folder"), computer.is_none());
+                assert!(menu.contains(&"Remove project"));
+            });
+        }
+    }
 
     #[gpui::test]
     fn inactive_project_rename_previews_and_failures_are_isolated_by_computer(