Wait for Ajax with Capybara Automatically

While writing feature tests involved in Ajax, we have to resolve race condition from time to time. Let's see the following code as an example.

spec/features/admin_deletes_product_spec.rb:

require 'spec_helper.rb'

feature "Admin deletes product category", { js: true} do
  before { page.driver.allow_url("fonts.googleapis.com") }
  after { clear_email }

  scenario "when the action is successful" do
    category = Fabricate(:product_category)
    product = Fabricate(:product, category: category)
    cloud = Fabricate(:admin)

    sign_in(cloud)
    visit admin_products_path
    find("a[id='delete_product_#{product.id}']").click

    # Without this line, there will be a race condition between deleting product and database query
    wait_for_ajax

    expect(Product.count).to eq 0
  end

end

where the function wait_for_ajax is used to make sure the product has been deleted before querying the count of products in database.

spec/support/wait_for_ajax.rb:

module WaitForAjax
  def wait_for_ajax
    Timeout.timeout(Capybara.default_wait_time) do
      loop until finished_all_ajax_requests?
    end
  end

  def finished_all_ajax_requests?
    page.evaluate_script('jQuery.active').zero?
  end
end

More discussion about this issue can be found in Thoughtbot's post.

Comments

Wait for Ajax with Capybara Automatically

Published

Category

Tags