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[rspec] view testing: testing the content_for results

I normally do not do a lot of view specs, but at least I want to make sure that my view renders without errors. And sometimes I really need to make sure that some link is shown or hidden depending on e.g. the role of the user or linked objects.

For example,

 describe "posts/show.html.haml" do
   context "without any comments" do
     it "displays no comments" do
       @post = Factory(:post)
       rendered.should contain(I18n.t(''))

So we check the rendered result, whether it contains a specific text.

But what happens if your view is rendering different yield regions? Like a body (the default region) and a sidebar.

Let's use a view like this :

  = show_for @post do |p|
    = p.attribute :title 
    = p.attribute :content
  - if @post.comments
    = render :partial => 'comments' 
  - else 
    = t('')
  = content_for :sidebar do
    = link_to 'Edit', edit_post(@post) if is_allowed_to?(:edit)

It renders the attributes using the show_for gem, and then renders inside the sidebar a link if the current user is allowed to edit it.

Now I want to test what is rendered into the sidebar. To my dismay I found that neither content_for or content_for?worked at all inside rspec.

And rendered does not contain the data for the other regions.

So somehow I would want to get to the content for :sidebar.

It appears that the different regions are actually stored inside an instance variable of the view. Once I figured that out, the rest was easy:

  describe "posts/show.html.haml" do
    def rendered_content_for(name)
    context "with enough rights" do
      it "displays a link to edit the post" do
        @post = Factory(:post)
        view.stub(:is_allowed_to?) { true }
        rendered_content_for(:sidebar).should contain('Edit') 
    context "with no rights" do
      it "does not display a link to edit the post" do
        @post = Factory(:post)
        view.stub(:is_allowed_to?) { false }
        render rendered_content_for(:sidebar).should_not contain('Edit')

Hope that this helps somebody. Or did you find a better way?

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Uncategorized view testing rspec2 rails3 rails rspec
rails3 and rspec2 view testing

Testing the view in Rspec is just great. It allows you to test the view in total isolation. It just does the render. Make sure you set up some data that is needed, and then check if all areas are available for instance. Now for Rspec2 a lot of things have changed:

  • have_tag is no longer supported: use have_selector from webrat instead
  • response is deprecated, use rendered instead
  • the assignment has changed, write assign(:events, [stub_model(Event)]) instead of using the old assigns[:events]=[...] notation Let me show you a full example, because that always makes things clearer: [ruby wraplines="false"] require 'spec_helper' DUMMY_NUMBER="dummy number" DUMMY_MESSAGE="dummy message" describe "envelopes/index.html.haml" do before (:each) do envelope = mock_model(Envelope) envelope.should_receive(:destination).and_return(DUMMY_NUMBER) envelope.should_receive(:message).and_return(DUMMY_MESSAGE) assign(:envelopes, [envelope]) render end it ("has a h1") { rendered.should have_selector('h1')} it ("shows the correct title") { rendered.should contain(t('envelopes.list.title')) } it ("have a table-grid") { rendered.should have_selector('.grid') } it ("shows the destination") { rendered.should contain(DUMMY_NUMBER) } it ("shows the message") { rendered.should contain(DUMMY_MESSAGE) } end [/ruby]
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