《Ruby on Rails 教程》第 4 章

自定义辅助方法

定义 full_title 辅助方法，编辑 app/helpers/application_helper.rb

module ApplicationHelper
  def full_title(page_title = '')
    base_title = "Ruby on Rails Tutorial Sample App"
    if page_title.empty?
      base_title
    else
      page_title + " | " + base_title
    end
  end
end

编辑 app/views/layouts/application.html.erb，替换 title

<title><%= full_title(yield(:title)) %></title>

把 home.html.erb 的 title 删除

编辑 test/controllers/static_pages_controller_test.rb，修改测试代码

require "test_helper"

class StaticPagesControllerTest < ActionDispatch::IntegrationTest
  def setup
    @base_title = "Ruby on Rails Tutorial Sample App"
  end

  test "should get root" do
    get static_pages_home_url
    assert_response :success
    assert_select "title", "#{@base_title}"
  end

  test "should get home" do
    get static_pages_home_url
    assert_response :success
    assert_select "title", "#{@base_title}"
  end

  test "should get help" do
    get static_pages_help_url
    assert_response :success
    assert_select "title", "Help | #{@base_title}"
  end

  test "should get about" do
    get static_pages_about_url
    assert_response :success
    assert_select "title", "About | #{@base_title}"
  end

  test "should get contact" do
    get static_pages_contact_url
    assert_response :success
    assert_select "title", "Contact | #{@base_title}"
  end
end

bin/rails test

测试成功！

代码：gitee.com/huzhengen/s…