fix: infinite loop when getting ancestor for orphan view (#5375)

frontend/rust-lib/event-integration-test/src/folder_event.rs

@@ -139,6 +139,24 @@ impl EventIntegrationTest {
     }
   }
 
+  /// Create orphan views in the folder.
+  /// Orphan view: the parent_view_id equal to the view_id
+  /// Normally, the orphan view will be created in nested database
+  pub async fn create_orphan_view(&self, name: &str, view_id: &str, layout: ViewLayoutPB) {
+    let payload = CreateOrphanViewPayloadPB {
+      name: name.to_string(),
+      desc: "".to_string(),
+      layout,
+      view_id: view_id.to_string(),
+      initial_data: vec![],
+    };
+    EventBuilder::new(self.clone())
+      .event(FolderEvent::CreateOrphanView)
+      .payload(payload)
+      .async_send()
+      .await;
+  }
+
   pub fn get_folder_data(&self) -> FolderData {
     let mutex_folder = self.appflowy_core.folder_manager.get_mutex_folder().clone();
     let folder_lock_guard = mutex_folder.read();
@@ -240,6 +258,18 @@ impl EventIntegrationTest {
       .await
       .parse::<ViewPB>()
   }
+
+  pub async fn get_view_ancestors(&self, view_id: &str) -> Vec<ViewPB> {
+    EventBuilder::new(self.clone())
+      .event(FolderEvent::GetViewAncestors)
+      .payload(ViewIdPB {
+        value: view_id.to_string(),
+      })
+      .async_send()
+      .await
+      .parse::<RepeatedViewPB>()
+      .items
+  }
 }
 
 pub struct ViewTest {

frontend/rust-lib/event-integration-test/tests/folder/local_test/folder_test.rs

@@ -1,6 +1,8 @@
 use collab_folder::ViewLayout;
 
+use event_integration_test::EventIntegrationTest;
 use flowy_folder::entities::icon::{ViewIconPB, ViewIconTypePB};
+use flowy_folder::entities::ViewLayoutPB;
 
 use crate::folder::local_test::script::FolderScript::*;
 use crate::folder::local_test::script::FolderTest;
@@ -331,3 +333,17 @@ async fn move_view_event_test() {
   assert_eq!(after_view_ids[0], view_ids[1]);
   assert_eq!(after_view_ids[1], view_ids[0]);
 }
+
+#[tokio::test]
+async fn create_orphan_child_view_and_get_its_ancestors_test() {
+  let test = EventIntegrationTest::new_anon().await;
+  let name = "Orphan View";
+  let view_id = "20240521";
+  test
+    .create_orphan_view(name, view_id, ViewLayoutPB::Grid)
+    .await;
+  let ancestors = test.get_view_ancestors(view_id).await;
+  assert_eq!(ancestors.len(), 1);
+  assert_eq!(ancestors[0].name, "Orphan View");
+  assert_eq!(ancestors[0].id, view_id);
+}

frontend/rust-lib/flowy-folder/src/manager.rs

@@ -530,6 +530,10 @@ impl FolderManager {
     while let Some(view) =
       self.with_folder(|| None, |folder| folder.views.get_view(&parent_view_id))
     {
+      // If the view is already in the ancestors list, then break the loop
+      if ancestors.iter().any(|v: &ViewPB| v.id == view.id) {
+        break;
+      }
       ancestors.push(view_pb_without_child_views(view.as_ref().clone()));
       parent_view_id = view.parent_view_id.clone();
     }