fixup

Author: ronag

lib/buffer.js

@@ -1108,15 +1108,16 @@ Buffer.prototype.write = function write(string, offset, length, encoding) {
     }
   }
 
-  const len = string.length;
+  const len = string?.length;
   if (
     len <= 16 &&
     len <= length &&
+    typeof string === 'string' &&
     (!encoding || encoding === 'ascii' || encoding === 'utf8')
   ) {
     let n = 0;
     while (true) {
-      const code = string.charCodeAt(n);
+      const code = StringPrototypeCharCodeAt(string, n);
       if (code >= 128) {
         break;
       }