From 2b9194cf424973b9efeafc2b6570d3381cb3cec4 Mon Sep 17 00:00:00 2001
From: Zixuan Chen <remch183@outlook.com>
Date: Sat, 12 Oct 2024 13:54:47 +0800
Subject: [PATCH] perf: optimize shrink frontiers

---
 crates/loro-internal/src/version.rs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/crates/loro-internal/src/version.rs b/crates/loro-internal/src/version.rs
index f1eac0e6..e178f210 100644
--- a/crates/loro-internal/src/version.rs
+++ b/crates/loro-internal/src/version.rs
@@ -1031,6 +1031,11 @@ pub fn shrink_frontiers(last_ids: &[ID], dag: &AppDag) -> Result<Frontiers, ID>
 
     let mut last_ids = {
         let ids = filter_duplicated_peer_id(last_ids);
+        if last_ids.len() == 1 {
+            frontiers.push(last_ids[0]);
+            return Ok(frontiers);
+        }
+
         let mut last_ids = Vec::with_capacity(ids.len());
         for id in ids {
             let Some(lamport) = dag.get_lamport(&id) else {
@@ -1042,11 +1047,6 @@ pub fn shrink_frontiers(last_ids: &[ID], dag: &AppDag) -> Result<Frontiers, ID>
         last_ids
     };
 
-    if last_ids.len() == 1 {
-        frontiers.push(last_ids[0].id());
-        return Ok(frontiers);
-    }
-
     // Iterate from the greatest lamport to the smallest
     last_ids.sort_by_key(|x| x.lamport);
     for id in last_ids.iter().rev() {