I wrote this library not for anything useful, but just as a learning experience.
$ cd /path/to/canary
$ node repl.js
canary> var tree = new BinarySearchTree();
canary> tree.addAll([9, 5, 2, 4, 6]);
canary> var node2 = tree.find(2);
canary> node2
{ left: null,
right: { left: null, right: null, key: 4, parent: [Circular] },
key: 2,
parent:
{ left: [Circular],
right: { left: null, right: null, key: 6, parent: [Circular] },
key: 5,
parent: { left: [Circular], right: null, key: 9, parent: null } } }