With actions such as `:show` and `:edit`, I can just http GET them. But since the `:update` action has no template, I can't issue a GET without it complaining about the missing template. That makes sense, so I tried to directly call `@controller.update` in my test, but I get an error on the `respond_to` block:

```
NoMethodError: undefined method `parameters' for nil:NilClass

```

How do I specify the requested format to be `:html`? I am passing in a parameter hash for the model's attributes, FWIW. Thanks for any advice.

Edit:
I since tried invoking @controller.update (after setting params[]) in the console and that error quoted above bubbled up from here: /actionpack-2.3.8/lib/action\_controller/mime\_responds.rb

I also tried PUT instead of GET, but still got "Missing Template update.erb". 

Also, I managed to find out that this error of missing template is caused by having anything other than a redirect or render in the code block marked HERE:

```
respond_to do |format|
  if @model.update_attributes(params[:model])
     flash[:notice] = 'note!'
     format.html { **HERE** }
     ...

```

I have a method call there that is just a conditional to redirect to the proper place. I can, in principle, understand why it might look for a template to render since it may not be aware that there is a redirect further downstream, but what I don't understand is how come my web application doesn't run into the same error as my functional test.