test: make sure linked lists are inspectable with defaults

Make sure that a long singly-linked list can be passed
to `util.inspect()` without causing a stack overflow.

PR-URL: #20017
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

test/parallel/test-util-inspect.js

@@ -1404,3 +1404,15 @@ util.inspect(process);
   const args = (function() { return arguments; })('a');
   assert.strictEqual(util.inspect(args), "[Arguments] { '0': 'a' }");
 }
+
+{
+  // Test that a long linked list can be inspected without throwing an error.
+  const list = {};
+  let head = list;
+  // The real cutoff value is closer to 1400 stack frames as of May 2018,
+  // but let's be generous here – even a linked listed of length 100k should be
+  // inspectable in some way.
+  for (let i = 0; i < 100000; i++)
+    head = head.next = {};
+  util.inspect(list);
+}