buffer: fix custom inspection with extra properties

This broke due to a recent change that prevents exposing inspect
internals. It now relies on the public API instead and should be a
bit more robust due to that.

PR-URL: https://github.com/nodejs/node/pull/27074
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Yongsheng Zhang <zyszys98@gmail.com>

lib/buffer.js

@@ -59,8 +59,7 @@ const {
   isUint8Array
 } = require('internal/util/types');
 const {
-  formatProperty,
-  kObjectType
+  inspect: utilInspect
 } = require('internal/util/inspect');
 
 const {
@@ -665,13 +664,24 @@ Buffer.prototype[customInspectSymbol] = function inspect(recurseTimes, ctx) {
     str += ` ... ${remaining} more byte${remaining > 1 ? 's' : ''}`;
   // Inspect special properties as well, if possible.
   if (ctx) {
+    let extras = false;
     const filter = ctx.showHidden ? ALL_PROPERTIES : ONLY_ENUMERABLE;
-    str += getOwnNonIndexProperties(this, filter).reduce((str, key) => {
-      // Using `formatProperty()` expects an indentationLvl to be set.
-      ctx.indentationLvl = 0;
-      str += `, ${formatProperty(ctx, this, recurseTimes, key, kObjectType)}`;
-      return str;
-    }, '');
+    const obj = getOwnNonIndexProperties(this, filter).reduce((obj, key) => {
+      extras = true;
+      obj[key] = this[key];
+      return obj;
+    }, Object.create(null));
+    if (extras) {
+      if (this.length !== 0)
+        str += ', ';
+      // '[Object: null prototype] {'.length === 26
+      // This is guarded with a test.
+      str += utilInspect(obj, {
+        ...ctx,
+        breakLength: Infinity,
+        compact: true
+      }).slice(27, -2);
+    }
   }
   return `<${this.constructor.name} ${str}>`;
 };