From 79aac977e9f2026464b3e5a907527f31a4eda871 Mon Sep 17 00:00:00 2001
From: Mathias Buus <mathiasbuus@gmail.com>
Date: Tue, 8 Oct 2024 13:20:42 +0200
Subject: [PATCH] fix own length when core is empty

---
 lib/core.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/core.js b/lib/core.js
index 780d9217..2e4d5415 100644
--- a/lib/core.js
+++ b/lib/core.js
@@ -705,7 +705,9 @@ module.exports = class Core {
 
       batch.nodes = srcNodes
 
-      if (this.header.tree.length < srcBatch.length) {
+      const ownLength = this.header.tree === null ? 0 : this.header.tree.length
+
+      if (ownLength < srcBatch.length) {
         batch.upgraded = true
         batch.length = srcBatch.length
         batch.byteLength = srcBatch.byteLength