Forum: RSpec view_context in specs

I have a presenter class which is instantiated like this:

class Blah

  def initialize(context)
    @context = context
  end

  def do_something_view_related
    @context.render :partial => "/...somewhere"
  end

  def do_something_else_view_related
    @context.content_tag :p, "fancy paragraph"
  end

end

class BlahController < ApplicationController

  def blah
    @blah = Blah.new(view_context)
  end

end

...

I've gotten around this in my specs by doing something like:

describe Blah do

  it "is blaherrific" do
    context = stub(:render => "some content...", :link_to => "<a
href="www.somewhere.com">somewhere</a>)
    blah = Blah.new(context)

    blah.do_someting_view_related.should == "some content..."
  end

end

But I would much rather actually be able to call upon the real view 
context in
my specs so that my tests are more realistic.

Is the best way to get a real-world view context in there to do 
something like:

Blah.new(ActionView::Base.new) ?

Or does RSpec have something magical already setup for this sort of 
thing?

Muchas Gracias.

Patrick J. Collins
http://collinatorstudios.com

On Nov 2, 2011, at 9:46 PM, Patrick J. Collins wrote:

>  end
>    @blah = Blah.new(view_context)
>  it "is blaherrific" do
> my specs so that my tests are more realistic.
>
> Is the best way to get a real-world view context in there to do something like:
>
> Blah.new(ActionView::Base.new) ?
>
> Or does RSpec have something magical already setup for this sort of thing?

Nope. rspec-rails doesn't know that you want to write presenters :)

I'd say just go w/ the real deal.

HTH,
David

On Nov 2, 2011, at 9:52 PM, David Chelimsky wrote:

>> def do_something_view_related
>>
>> describe Blah do
>>
>
> I'd say just go w/ the real deal.

I should qualify that: I'd say just _start_ with the real deal. If it 
turns out painful, then look for alternatives.

> > Is the best way to get a real-world view context in there to do something 
like:
> >
> > Blah.new(ActionView::Base.new) ?
> >
> > Or does RSpec have something magical already setup for this sort of thing?
>
> Nope. rspec-rails doesn't know that you want to write presenters :)
>
> I'd say just go w/ the real deal.

Ok cool, thanks.  It turns out ActionView::Base.new is a bit of a pain 
to try to
use in this case since it lacks configuration of view paths and such. 
So what
appears to be the simplest way to get this functionality is to do:

@context = ActionController::Base.new.view_context

then you can do @context.render, @context.content_tag, etc.

Patrick J. Collins
http://collinatorstudios.com

If you put this on your spec_helper.rb

//If you have your spec in the directory "spec/presenters"
config.include ActionView::TestCase::Behavior, example_group:
{file_path: %r{spec/presenters}}

Then you can use a method, :view, that you can use as the view context
like this

let(:profile) { ProfilePresenter.new(@user, view) }


....... There is a Railscast about it.