stream: improve buffer list inspection

This makes sure the indentation level is correct, no matter if the inspected buffer list is inspected on a deeper level and custom inspect options are now passed through to the actual inspection. PR-URL: #23109 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>

Author: BridgeAR

lib/internal/streams/buffer_list.js

@@ -158,8 +158,14 @@ module.exports = class BufferList {
  return ret;
  }
 
- [inspect.custom]() {
- const obj = inspect({ length: this.length });
- return `${this.constructor.name} ${obj}`;
+ // Make sure the linked list only shows the minimal necessary information.
+ [inspect.custom](_, options) {
+ return inspect(this, {
+ ...options,
+ // Only inspect one level.
+ depth: 0,
+ // It should not recurse.
+ customInspect: false
+ });
  }
 };

test/parallel/test-stream2-readable-from-list.js

@@ -25,6 +25,7 @@ require('../common');
 const assert = require('assert');
 const fromList = require('_stream_readable')._fromList;
 const BufferList = require('internal/streams/buffer_list');
+const util = require('util');
 
 function bufferListFromArray(arr) {
  const bl = new BufferList();
@@ -41,6 +42,16 @@ function bufferListFromArray(arr) {
  Buffer.from('kuel') ];
  list = bufferListFromArray(list);
 
+ assert.strictEqual(
+ util.inspect([ list ], { compact: false }),
+ `[
+ BufferList {
+ head: [Object],
+ tail: [Object],
+ length: 4
+ }
+]`);
+
  // read more than the first element.
  let ret = fromList(6, { buffer: list, length: 16 });
  assert.strictEqual(ret.toString(), 'foogba');