Should be fixed: http://www.codewars.com/kumite/587046cfd58bed48b50000bf?sel=5bd08e21dbc7397ec1000479

Huh, I could have sworn I caught that one.

This should be all fixed up now.

That makes sense, I wrote it before 1.6 was out. :)

Let me work on updating it.

This has a bug not detected by the current test suite. I was attempting to avoid a separate depth computation.

It will incorrectly indicate that a tree that looks like the following is perfect:

  TreeNode root = TreeNode.join(
    TreeNode.join(
      new TreeNode().withChildren(
        TreeNode.leaf(),
        TreeNode.leaf()
      ),
      new TreeNode().withChildren(
        TreeNode.leaf(),
        TreeNode.leaf()
      )
    ),
    new TreeNode().withChildren(
      TreeNode.leaf(),
      TreeNode.leaf()
    )
  );

This has a bug not detected by the current test suite. I was attempting to avoid a separate depth computation.

It will incorrectly indicate that a tree that looks like the following is perfect:

  TreeNode root = TreeNode.join(
    TreeNode.join(
      new TreeNode().withChildren(
        TreeNode.leaf(),
        TreeNode.leaf()
      ),
      new TreeNode().withChildren(
        TreeNode.leaf(),
        TreeNode.leaf()
      )
    ),
    new TreeNode().withChildren(
      TreeNode.leaf(),
      TreeNode.leaf()
    )
  );