From 3ba8ad5f12268b8d95f115635d9dc9cfbd553513 Mon Sep 17 00:00:00 2001
From: Zixuan Chen <remch183@outlook.com>
Date: Sun, 18 Aug 2024 15:07:56 +0800
Subject: [PATCH] fix: getting parent for root container error

---
 crates/loro-internal/src/arena.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/crates/loro-internal/src/arena.rs b/crates/loro-internal/src/arena.rs
index de951fcd..76601e76 100644
--- a/crates/loro-internal/src/arena.rs
+++ b/crates/loro-internal/src/arena.rs
@@ -216,6 +216,12 @@ impl SharedArena {
     }
 
     pub fn get_parent(&self, child: ContainerIdx) -> Option<ContainerIdx> {
+        if self.get_container_id(child).unwrap().is_root() {
+            // TODO: PERF: we can speed this up by use a special bit in ContainerIdx to indicate
+            // whether the target is a root container
+            return None;
+        }
+
         self.inner
             .parents
             .lock()