Rails style link_to helper for active nav links.

nav_link_to.rb

def nav_link_to(*args, **options, &block)
  class_names = ['nav-main-link']
  link_path =
    case args.length
    when 1
      args[0]
    when 2
      args[1]
    end
  class_names << 'active' if current_page?(link_path)
  class_names += Array(options[:class])

  link_to *args, class: class_names, **options, &block
end