Error

› rake spec cucumber
/Users/rpowell93/.rvm/rubies/ruby-1.9.3-p0/bin/ruby -S rspec ./spec/controllers/books_controller_spec.rb ./spec/helpers/books_helper_spec.rb ./spec/models/book_spec.rb ./spec/views/books/new.html.erb_spec.rb
..F

Failures:

  1) books/new.html.erb should render a form to add a new book
     Failure/Error: render
     ActionView::Template::Error:
       No input found for Book_#<RSpec::Core::ExampleGroup::Nested_3:0x007fedfdb83510>
     # ./app/views/books/new.html.erb:4:in `block in _app_views_books_new_html_erb___2832296693760024294_70330069700200'
     # ./app/views/books/new.html.erb:3:in `_app_views_books_new_html_erb___2832296693760024294_70330069700200'
     # ./spec/views/books/new.html.erb_spec.rb:9:in `block (2 levels) in <top (required)>'

Finished in 3.18 seconds
3 examples, 1 failure

Failed examples:

rspec ./spec/views/books/new.html.erb_spec.rb:8 # books/new.html.erb should render a form to add a new book
rake aborted!
ruby /Users/rpowell93/.rvm/rubies/ruby-1.9.3-p0/bin/ruby -S rspec ./spec/controllers/books_controller_spec.rb ./spec/helpers/books_helper_spec.rb ./spec/models/book_spec.rb ./spec/views/books/new.html.erb_spec.rb failed

Tasks: TOP => spec
(See full trace by running task with --trace)

new.html.erb

<h1>Books#new</h1>

<%= simple_form_for @book do |f| %>
  <%= f.input :title %>
  <%= f.input :author %>
  <%= f.button :submit, "Add book" %>
<% end %>

new.html.erb_spec.rb

require 'spec_helper'

describe "books/new.html.erb" do
  before :each do
    @book = mock_model("Book").as_null_object
  end

  it "should render a form to add a new book" do
    render 
    rendered.should have_selector("form[method=post]", :action => books_path)
    rendered.should have_selector("input[type=text]#book_title")
    rendered.should have_selector("input[type=text]#book_author")
    rendered.should have_selector("input[type=submit]")
  end
end