ruby-on-rails – Capybara :: ElementNotFound,但它就在那里

Capybara::ElementNotFound: Unable to find field "username"
./spec/controllers/sessions_controller_spec.rb:10:in `block (3 levels) in <top (required)>'

规格：

require 'spec_helper'

describe SessionsController do
  before :each do
    @user = FactoryGirl.create(:user)
  end
  context 'creating a new session' do
    it 'can set the current_user variable to the logged user' do
      visit '/login'
      fill_in 'username',with: 'gabrielhilal' #I have tried `Username` as well
      fill_in 'password',with: 'secret'
      click_button 'Login'
      current_user.should == @user
      current_user.username.should == 'gabrielhilal'
    end
  end
  context 'destroying existing session' do
    xit 'can destroy the current_user' do
    end
  end
end

但是我的表单中有字段用户名：

<form accept-charset="UTF-8" action="/sessions" method="post"><div style="margin:0;padding:0;display:inline"><input name="utf8" type="hidden" value="&#x2713;" / <input name="authenticity_token" type="hidden" value="x7ORLDIvq1BXr8SOkd/Zla9Pl5R5tBXAtyflCpTGCtY=" /></div>
  <div class="field">
    <label for="username">Username</label>
    <input id="username" name="username" type="text" />
  </div>
  <div class="field">
    <label for="password">Password</label>
    <input id="password" name="password" type="password" />
  </div>
  <div class="actions">
    <input name="commit" type="submit" value="Login" />
  </div>
</form>

我用黄瓜进行了类似的测试,它正在传递,这证实了字段用户名是：When to switch from cucumber to rspec in the BDD cycle for a login procedure

任何的想法？

编辑 – 我添加了save_and_open_page,它给了我一个空白页面.投注“#{page.html.inspect}”也会返回empity.

""

Capybara::ElementNotFound: Unable to find field "username"
./spec/controllers/sessions_controller_spec.rb:12:in `block (3 levels) in <top (required)>'