我正在为练习构建一个简单的Reddit Clone,并且想测试ajax是否正常工作以及屏幕上的值是否通过javascript响应正确更新。这是测试:
RSpec.describe "User voting", type: :system, js: true do # Rails 5 uses describe, Rails < 5 feature
it "updates the downvote count" do
user = create(:user)
login_as(user)
link = create(:link)
visit root_path
expect(page).to have_css('#upvotes-1', text: '0')
click_on(id: 'upvoter-1')
wait_for_ajax
expect(page).to have_css('#upvotes-1', text: '1')
end
end
wait_for_ajax :(在/spec/support/wait_for_ajax.rb中)
module WaitForAjax
def wait_for_ajax
Timeout.timeout(Capybara.default_max_wait_time) do
loop until finished_all_ajax_requests?
end
end
def finished_all_ajax_requests?
page.evaluate_script('jQuery.active').zero?
end
end
index.html.erb中的相对代码:
<%= button_tag(class: "btn btn-secondary btn-sm", id: "upvoter-#{link.id}") do %>
<span class="fa fa-chevron-up"></span>
Upvote
<%= content_tag(:span, link.upvotes(), id: "upvotes-#{link.id}") %>
<% end %>
控制器代码:
def create
@vote = current_user.votes.new(link_params)
if @vote.vote_value == 1
@new_value = @vote.link.upvotes
@id_name = "#upvotes-" + @vote.link.id.to_s
else
@new_value = @vote.link.downvotes
@id_name = "#downvotes-" + @vote.link.id.to_s
end
respond_to do |format|
if @vote.save
format.js { }
else
format.html { render :new }
end
end
end
最后是create.js.erb:
console.log("create.js.erb file");
$("<%= j @id_name %>").html("<%= j @new_value.to_s %>");
的Gemfile:
group :development, :test do
# Call 'byebug' anywhere in the code to stop execution and get a debugger console
gem 'byebug'
gem 'rspec-rails'
gem 'guard-rspec', require: false
gem 'factory_bot_rails', '~> 4.0'
gem 'database_cleaner'
gem 'rails-controller-testing'
gem 'capybara', '~> 2.13'
gem 'selenium-webdriver'
gem 'chromedriver-helper'
gem 'puma'
gem 'poltergeist'
end
如果我自己加载网站并单击按钮,则计数器会正确更新。但是,测试失败的第二个期望。如果我重新加载页面,计数器将更新,以便更新数据库并且#create按预期工作。由于某种原因,javascript没有被执行。而且我也试过在click_on之后睡一觉。它仍然失败。这里似乎有一些简单的东西。
切换到Selenium帮助我更清楚地看到问题。这是一个非常好的教程,告诉你如何使用Rails 5 /最新(2018年末)版本的东西进行设置:
A Quick Guide to Rails System Tests in RSpec
最后,我使用.new来创建模型,但没有保存它,所以没有显示新的投票计数。保存后移动计数的逻辑解决了问题。
在votes_controller.rb中:
def create
@vote = current_user.votes.new(link_params)
respond_to do |format|
if @vote.save
format.js {
if @vote.vote_value == 1
@new_value = @vote.link.upvotes
@id_name = "#upvotes-" + @vote.link.id.to_s
else
@new_value = @vote.link.downvotes
@id_name = "#downvotes-" + @vote.link.id.to_s
end
}
else
format.html { render :new }
end
end
end