From 609f51a26a15ab09b70a57c1638e34acb2e41541 Mon Sep 17 00:00:00 2001
From: Yanzhen Yu <yanzhen@smartx.com>
Date: Wed, 1 Apr 2026 12:00:00 +0800
Subject: [PATCH] add a has method to mirror for checking whether an id is in
 the map

---
 src/types.ts | 3 ++-
 src/utils.ts | 5 ++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/types.ts b/src/types.ts
index fe50ed3c..4eeae747 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -209,8 +209,9 @@ export type inputCallback = (v: inputValue & { id: number }) => void;
 export type Mirror = {
   map: idNodeMap;
   getId: (n: INode) => number;
-  getNode: (id: number) => INode;
+  getNode: (id: number) => INode | null;
   removeNodeFromMap: (n: INode) => void;
+  has: (id: number) => boolean;
 };
 
 export type throttleOptions = {
diff --git a/src/utils.ts b/src/utils.ts
index 4ce58911..66e5c85c 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -21,7 +21,7 @@ export const mirror: Mirror = {
     return n.__sn && n.__sn.id;
   },
   getNode(id) {
-    return mirror.map[id];
+    return mirror.map[id] || null;
   },
   // TODO: use a weakmap to get rid of manually memory management
   removeNodeFromMap(n) {
@@ -33,6 +33,9 @@ export const mirror: Mirror = {
       );
     }
   },
+  has(id) {
+    return mirror.map.hasOwnProperty(id);
+  },
 };
 
 // copy from underscore and modified