View.should render_template best practices?

Testing RSpec
1

I’ve been looking for the definitive answer for months now, and the
RSpec book doesn’t touch on it at all:

How do we now handle stubbing out rendering of partials in view specs
in RSpec2?

I have a large (35K+ lines of views and related specs) that I’m trying
to upgrade to Rails3/RSpec2. My views use partials pretty extensively
and this issue is a huge blocker for me.

before do
view.should render_template(“event_list”, :locals => {:calendar =>
@calendar})
end

causes all my related specs fail with:

expecting <“event_list”> but rendering with <"">.
Expected block to return true value.

Any advice?

2

render_template matcher is to be used after the view is rendered.
In your case something like
view.stub!(:render).with(:partial => “event_list”, :locals =>
{:calendar => @calendar})
should do the trick

3

I’m sorry for introducing the confusion, but view.stub!(:render) won’t
work,
I should’ve read the list more attention
http://groups.google.com/group/rspec/browse_thread/thread/1590942f2827f55

4

On Nov 16, 2010, at 8:16 AM, Matt D. wrote:

before do
Any advice?
In rspec-2/rails-3, view.should render_template(“event_list”) is no
longer a message expectation (pre-action), but rather delegates to
Rails’ assert_template method, so it needs to come after the action.
It should work exactly as you have it above, just after the action.

This is documented in the rspec-rails README
(GitHub - rspec/rspec-rails: RSpec for Rails 5+ - see sections on View Specs and
Matchers), though not with an upgrade note pointing out that it changed.
I’ll make that addition shortly.

As for stubbing the template, so that it is not actually rendered, RSpec
doesn’t offer a way to do this in view specs and I don’t think Rails
does either. I added an issue for this
(Need a means of stubbing partials · Issue #263 · rspec/rspec-rails · GitHub), and hopefully
we’ll be able to resolve it soon. In the mean time, the examples will
need to supply any data needed by the template being spec’d and any of
the partials.

Side note: I urge you not to put message expectations (pre “When”) or
state-based expectations (post “When”) in before/after blocks. It makes
examples difficult to understand, and results in specifying the same
things in every example in a group. Rather, have one example that
specifies each individual thing. In this case:

it “renders the event_list with @calendar” do
render
view.should render_template(
“event_list”,
:locals => {:calendar => @calendar}
)
end

HTH,
David

5

On Nov 17, 2010, at 5:37 AM, David C. wrote:

and this issue is a huge blocker for me.

it “renders the event_list with @calendar” do
render
view.should render_template(
“event_list”,
:locals => {:calendar => @calendar}
)
end

FYI - it looks like you can do the following before the action, but
you’d be using an internal method of Rails which is not guaranteed to
work the same way in the future:

view.should_receive(:_render_partial).with(
  :partial => "event_list",
  :locals => { :calendar => @calendar }
)

Do not use this unless you are willing to absorb the risk that it could
change in a future Rails release without any warning.