Question

Hi I’m currently going through a tutorial on testing. We’re building helper methods for highlighting the tabs in the nav bar. Here are the helper methods.

module RecipesHelper
  def tabs(current_tab)
    content_tag(:div, links(current_tab), :id => "tabs")
  end

  def links(current_tab)
    nav_items.map do |tab_name, path|
      args = tab_name, path

      if tab_name == current_tab
         args << {:class => "current"}
      end
      link_to *args
    end.join(separator).html_safe
  end

  def nav_items
    {
      "New" => new_recipe_path,
      "List" => recipes_path,
      "Home" => root_path
    }
  end

  def separator
    content_tag(:span, "|", :class => "separator").html_safe
  end
end

here is one of the tests:

require 'test_helper'
class RecipesHelperTest < ActionView::TestCase
  test "current tab is correct" do
    render :text => tabs("New")
    assert_select "a[class='current']" do |anchors|
      anchors.each do |anchor|
        assert_equal new_recipe_path, anchor.attributes['href']
      end
    end
  end
end

My question is what does the anchors variable passed in the block? Same question for the nested block with anchor. Thanks.

Answer 1

If you read the documentation on assert_select it will get a list of all the matching elements. In this case a[class='current'] will probably return a list of a tags(anchors).

It then it loops through that list and assert_equal if the href attribute of that single a tag matches the new_recipe_path

assert_select docs