修复:未选中板拆单时错误

src/Add-on/CheckHoles.ts

@@ -45,6 +45,8 @@ export class CheckHoles implements Command
 //干涉检查
 export async function InterferenceCheck(brs: Board[])
 {
+    if (!brs.length) return [];
+
     const drillTool = DrawDrillingTool.GetInstance();
     let b2boxMap = new Map<Board, ObjectId[][]>();