For example, ruby-mode used smie-setup that sets
buffer-local show-paren-data-function.

This patch does the same for ts-modes: when point at the start/end
of the sexp list, then both "def" and "end" are highlighted
as opening and closing nodes:

  def method
    puts "This is method definition"
  end-!-

This also indicates that implementing 'down-list' to move after the
opening node will be the right thing to do (currently in progress).