Capybara doesn't recognize dynamically added D

问题:

I seem to be having trouble testing the slick javascript things I do with jQuery when using Capybara and Selenium. The expected behavior is for a form to be dynamically generated when a user clicks on the link "add resource". Capybara will be able to click the link, but fails to recognize the new form elements (i.e. "resource[name]").

Is there a way to reload the DOM for Capybara, or is there some element of this gem that I just haven't learned of yet?

Thanks in advance!

==Edit==

Currently trying my luck with selenium's:

wait_for_element 

method.

==Edit==

I keep getting an "undefined method 'wait_for_element` for nill class" when attempting to do the following:

@selenium.wait_for_element

It appears that that specific method, or perhaps wait_for with a huge selector accessing the DOM element I expect is the correct course of action, but now trying to get the selenium session is starting to be a huge headache.

回答1:

I use the Webdriver based driver for Capybara in RSpec, which I configure and use like this and it will definitely handle JS and doesn't need a reload of the dom. The key is using a wait_until and a condition that will be true when your AJAX response has finished.

before(:each) do
  select_driver(example)  
  logout
  login('databanks') 
end

 def select_driver(example)
   if example.metadata[:js]
    Capybara.current_driver = :selenium
  else
    Capybara.use_default_driver
  end
end

it "should let me delete a scenario", :js=>true do
    select("Mysite Search", :from=>'scenario_id')  
    wait_until{ page.has_content?('mysite_searchterms')}    
    click_on "delete"     
    wait_until{ !page.has_content?('mysite_searchterms')}   
    visit '/databanks'
    page.should_not have_content('Mysite Search')
  end

I also figured out a hack to slow down webdriver last night, like this, if you want to watch things in slo-mo:

   #set a command delay
   require 'selenium-webdriver'

   module ::Selenium::WebDriver::Remote
     class Bridge
       def execute(*args)
         res = raw_execute(*args)['value']
         sleep 0.5
         res
       end
     end
   end  

As someone else mentioned, if you are getting a timeout waiting for the element, you could look at upping this:

Capybara.default_wait_time = 10

回答2:

From the Capybara docs:

When working with asynchronous JavaScript, you might come across situations where you are attempting to interact with an element which is not yet present on the page. Capybara automatically deals with this by waiting for elements to appear on the page.

You might have some luck increasing the wait time:

Capybara.default_wait_time = 10

If that doesn't help then I would encorage you to contact somebody from the project on GitHub, write to the mailing list or submit an issue report.

回答3:

Even wait_until deleted from Capybara 2.0. Still that's useful and grab code from below:

 def wait_until(delay = 1)   
 seconds_waited = 0   
 while ! yield && seconds_waited < Capybara.default_wait_time     
    sleep delay     
    seconds_waited += 1   
  end   
  raise "Waited for #{Capybara.default_wait_time} seconds but condition did not become true" unless yield 
end