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Week 8 - TDD and unit testing

Flash Messages

Allows you to send messages back to user like Book was succesfully created. Renders regardless of which page you refresh to.

Two different types of messages

  • :notice - success messages
  • :alert - error messages

Steps

  1. Update spec/features/book_management_spec.rb to test for flash message

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path

    click_link "Books"
    click_link "Add book"

    fill_in "Title", with: "Garfield"
    fill_in "Pages", with: "250"

    click_button "Save"

    expect(page).to have_content "successfully created"
  end
end

  2. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: expect(page).to have_content "successfully created"
       expected to find text "successfully created" in "Books Garfield"
     # ./spec/features/book_management_spec.rb:15:in `block (2 levels) in <top (required)>'

Finished in 0.24735 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 36959

  3. Update the create method app/controllers/books_controller.rb

      def create
    @book = Book.new book_params
    if @book.save
      flash[:notice] = "Book successfully created."
      redirect_to @book
    else
      render "new"
    end
  end

  4. Update the app/views/layouts/application.html.erb to render flash mesages

    <!DOCTYPE html>
<html>
<head>
  <title>Readathon App</title>
  <%= stylesheet_link_tag    "application", media: "all", "data-turbolinks-track" => true %>
  <%= javascript_include_tag "application", "data-turbolinks-track" => true %>
  <%= csrf_meta_tags %>
</head>
<body>
  <%= link_to "Books", books_path %>

  <% flash.each do |name, msg| %>
  <div class="flash <%= name %>"><%= msg %></div>
  <% end %>

<%= yield %>

</body>
</html>

  5. Run the specs

    $ rspec spec/features/book_management_spec.rb
.

Finished in 0.76564 seconds
1 example, 0 failures

Randomized with seed 61984

  6. Commit

    $ git add .
$ git commit -m "Added flash messages"

  7. Fire up the server and check it out

Edit and Delete

  1. Update spec to include edit and delete

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path

    click_link "Books"
    click_link "Add book"

    fill_in "Title", with: "Garfield"
    fill_in "Pages", with: "250"

    click_button "Save"

    expect(page).to have_content "successfully created"

    click_link "Edit"
    fill_in "Title", with: "Calvin and Hobbes"
    click_button "Save"

    expect(page).to have_content "successfully updated"
    expect(page).to have_content "Calvin and Hobbes"

    click_link "Delete"
    expect(page).to have_content "successfully deleted"
  end
end

  2. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Edit"
     Capybara::ElementNotFound:
       Unable to find link "Edit"
     # ./spec/features/book_management_spec.rb:17:in `block (2 levels) in <top (required)>'

Finished in 0.24665 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 48927

  3. Add edit link in app/views/books/show.html.erb

    <%= link_to "Edit", edit_book_path(@book) %>

<h1><%= @book.title %></h1>

  4. Run spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_button "Save"
     ActionView::Template::Error:
       undefined method `edit_book_path' for #<#<Class:0x00000003aa1da8>:0x0000000481d090>
     # ./app/views/books/show.html.erb:1:in `_app_views_books_show_html_erb__4335723529987197110_37835000'
     # ./spec/features/book_management_spec.rb:13:in `block (2 levels) in <top (required)>'

Finished in 0.7835 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 14255

  5. Update config/routes.rb

    Readathon::Application.routes.draw do
  root "pages#index"

  resources :books, only: [:index, :new, :create, :show, :edit]
end

  6. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Edit"
     AbstractController::ActionNotFound:
       The action 'edit' could not be found for BooksController
     # ./spec/features/book_management_spec.rb:17:in `block (2 levels) in <top (required)>'

Finished in 0.26976 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 59630

  7. Add the edit action to the books controller

    class BooksController < ApplicationController
  def index
  end

  def new
    @book = Book.new
  end

  def create
    @book = Book.new book_params
    if @book.save
      flash[:notice] = "Book successfully created."
      redirect_to @book
    else
      render "new"
    end
  end

  def show
    @book = Book.find params[:id]
  end

  def edit
    @book = Book.find params[:id]
  end

  private

  def book_params
    params.require(:book).permit(:title, :pages)
  end
end

  8. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Edit"
     ActionView::MissingTemplate:
       Missing template books/edit, application/edit with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :raw, :ruby, :coffee, :jbuilder]}. Searched in:
         * "/home/action/workspace/readathon/app/views"
     # ./spec/features/book_management_spec.rb:17:in `block (2 levels) in <top (required)>'

Finished in 0.76224 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 46924

  9. Create app/views/books/edit.html.erb

    <%= simple_form_for @book do |f| %>
  <%= f.input :title %>
  <%= f.input :pages %>

  <%= f.submit "Save" %>
<% end %>

  10. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_button "Save"
     ActionController::RoutingError:
       No route matches [PATCH] "/books/8"
     # ./spec/features/book_management_spec.rb:19:in `block (2 levels) in <top (required)>'

Finished in 0.76454 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 13097

  11. Add the update route

    Readathon::Application.routes.draw do
  root "pages#index"

  resources :books, only: [:index, :new, :create, :show, :edit, :update]
end

  12. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_button "Save"
     AbstractController::ActionNotFound:
       The action 'update' could not be found for BooksController
     # ./spec/features/book_management_spec.rb:19:in `block (2 levels) in <top (required)>'

Finished in 0.29706 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 61146

  13. Create update action in app/controllers/books_controller.rb

    class BooksController < ApplicationController
  # Other actions omitted

  def update
    @book = Book.find params[:id]
    if @book.update_attributes book_params
      flash[:notice] = "Book successfully updated."
      redirect_to @book
    else
      render "edit"
    end
  end
end

  14. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Delete"
     Capybara::ElementNotFound:
       Unable to find link "Delete"
     # ./spec/features/book_management_spec.rb:24:in `block (2 levels) in <top (required)>'

Finished in 0.79845 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 15875

  15. Add a delete link to app/views/books/show.html.erb

    <%= link_to "Edit", edit_book_path(@book) %> |
<%= link_to "Delete", @book, method: :delete %>

<h1><%= @book.title %></h1>

  16. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Delete"
     ActionController::RoutingError:
       No route matches [DELETE] "/books/15"
     # ./spec/features/book_management_spec.rb:24:in `block (2 levels) in <top (required)>'

Finished in 0.78999 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 23182

  17. Add the destroy route

    Readathon::Application.routes.draw do
  root "pages#index"

  resources :books, only: [:index, :new, :create, :show, :edit, :update, :destroy]
end

  18. Run the spec

    $ rspec spec/features/book_management_spec.rb
F

Failures:

  1) Book management User manages books
     Failure/Error: click_link "Delete"
     AbstractController::ActionNotFound:
       The action 'destroy' could not be found for BooksController
     # ./spec/features/book_management_spec.rb:24:in `block (2 levels) in <top (required)>'

Finished in 0.3065 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 54552

  19. Add the destroy action

    class BooksController < ApplicationController
  # Other actions omitted...

  def destroy
    @book = Book.find params[:id]
    if @book.destroy
      flash[:notice] = "Book successfully deleted."
    end
    redirect_to books_path
  end
end

  20. Run the spec

    $ rspec spec/features/book_management_spec.rb
.

Finished in 0.80757 seconds
1 example, 0 failures

Randomized with seed 3856

  21. Commit

    $ git add .
$ git commit -m "Finished book crud"

Refactoring

  1. Let's start by making the spec more readable. spec/features/book_management_spec.rb

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path

    click_link "Books"
    click_link "Add book"

    fill_in "Title", with: "Garfield"
    fill_in "Pages", with: "250"

    click_button "Save"

    user_sees_flash_message "successfully created"

    click_link "Edit"
    fill_in "Title", with: "Calvin and Hobbes"
    click_button "Save"

    user_sees_flash_message "successfully updated"
    expect(page).to have_content "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end
end

  2. Run the spec and make sure things still work

    $ rspec spec/features/book_management_spec.rb
.

Finished in 0.81859 seconds
1 example, 0 failures

Randomized with seed 14977

  3. Extract button saving

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path

    click_link "Books"
    click_link "Add book"

    fill_in "Title", with: "Garfield"
    fill_in "Pages", with: "250"
    save

    user_sees_flash_message "successfully created"

    click_link "Edit"
    fill_in "Title", with: "Calvin and Hobbes"
    save

    user_sees_flash_message "successfully updated"
    expect(page).to have_content "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end

  def save
    click_button "Save"
  end
end

  4. Run the spec and make sure things still work

    $ rspec spec/features/book_management_spec.rb
.

Finished in 0.80727 seconds
1 example, 0 failures

Randomized with seed 37814

  5. Extract book adding

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path
    click_link "Books"

    add_book_with_title "Garfield"

    user_sees_flash_message "successfully created"

    click_link "Edit"
    fill_in "Title", with: "Calvin and Hobbes"
    save

    user_sees_flash_message "successfully updated"
    expect(page).to have_content "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def add_book_with_title title
    click_link "Add book"

    fill_in "Title", with: title
    fill_in "Pages", with: "250"
    save
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end

  def save
    click_button "Save"
  end
end

  6. Run the spec and make sure it still works

  7. Extract editing book title

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path
    click_link "Books"

    add_book_with_title "Garfield"

    user_sees_flash_message "successfully created"

    edit_book_title "Calvin and Hobbes"

    user_sees_flash_message "successfully updated"
    expect(page).to have_content "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def add_book_with_title title
    click_link "Add book"

    fill_in "Title", with: title
    fill_in "Pages", with: "250"
    save
  end

  def edit_book_title title
    click_link "Edit"
    fill_in "Title", with: title
    save
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end

  def save
    click_button "Save"
  end
end

  8. Run the spec and make sure things still work

  9. Extract the book title to helper

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path
    click_link "Books"

    add_book_with_title "Garfield"

    user_sees_flash_message "successfully created"

    edit_book_title "Calvin and Hobbes"

    user_sees_flash_message "successfully updated"
    user_sees_book_title "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def add_book_with_title title
    click_link "Add book"

    fill_in "Title", with: title
    fill_in "Pages", with: "250"
    save
  end

  def edit_book_title title
    click_link "Edit"
    fill_in "Title", with: title
    save
  end

  def user_sees_book_title title
    expect(page).to have_content title
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end

  def save
    click_button "Save"
  end
end

  10. Run the spec to make sure it still passes

  11. Commit

    $ git add .
$ git commit -m "Refactored test to help readability"

  12. Extract book loading into before filter in app/controllers/books_controller.rb

    class BooksController < ApplicationController
  before_filter :find_book, only: [ :show, :edit, :update, :destroy]

  def index
  end

  def new
    @book = Book.new
  end

  def create
    @book = Book.new book_params
    if @book.save
      flash[:notice] = "Book successfully created."
      redirect_to @book
    else
      render "new"
    end
  end

  def show
  end

  def edit
  end

  def update
    if @book.update_attributes book_params
      flash[:notice] = "Book successfully updated."
      redirect_to @book
    else
      render "edit"
    end
  end

  def destroy
    if @book.destroy
      flash[:notice] = "Book successfully deleted."
    end
    redirect_to books_path
  end


  private

  def find_book
    @book = Book.find params[:id]
  end

  def book_params
    params.require(:book).permit(:title, :pages)
  end
end

  13. Run your spec and make sure it still works.

  14. Commit

    $ git add .
$ git commit -m "Extracted out book loading into before filter"

  15. Extract new and edit html into app/views/books/_form.html.erb

    <%= simple_form_for @book do |f| %>
  <%= f.input :title %>
  <%= f.input :pages %>

  <%= f.submit "Save" %>
<% end %>

  16. Update app/views/books/edit.html.erb and app/views/books/new.html.erb to use the partial

    <%= render partial: "form" %>

  17. Run the spec and make sure it still works

  18. Commit

    $ git add .
$ git commit -m "Extracted book form into partial"

Matching elements with CSS selectors

  1. Update the form so you don't explicitly name the submit button "Save"

    <%= simple_form_for @book do |f| %>
  <%= f.input :title %>
  <%= f.input :pages %>

  <%= f.submit %>
<% end %>

  2. Run the spec

    Failures:

  1) Book management User manages books
     Failure/Error: click_button "Save"
     Capybara::ElementNotFound:
       Unable to find button "Save"
     # ./spec/features/book_management_spec.rb:44:in `save'
     # ./spec/features/book_management_spec.rb:26:in `add_book_with_title'
     # ./spec/features/book_management_spec.rb:8:in `block (2 levels) in <top (required)>'

Finished in 0.73467 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books

Randomized with seed 40644

  3. Start up the server and see what else you could reference the submit button by

  4. Modify your test to use the css selector "input[type=submit]"

    require "spec_helper"

feature "Book management" do
  scenario "User manages books" do
    visit root_path
    click_link "Books"

    add_book_with_title "Garfield"

    user_sees_flash_message "successfully created"

    edit_book_title "Calvin and Hobbes"

    user_sees_flash_message "successfully updated"
    user_sees_book_title "Calvin and Hobbes"

    click_link "Delete"
    user_sees_flash_message "successfully deleted"
  end

  def add_book_with_title title
    click_link "Add book"

    fill_in "Title", with: title
    fill_in "Pages", with: "250"
    save
  end

  def edit_book_title title
    click_link "Edit"
    fill_in "Title", with: title
    save
  end

  def user_sees_book_title title
    expect(page).to have_content title
  end

  def user_sees_flash_message msg
    expect(page).to have_content msg
  end

  def save
    find("input[type=submit]").click
  end
end

  5. Run the spec to make sure it still works

  6. Commit

    $ git add .
$ git commit -m "Changed submit buttons to use default text"

  7. Update config/routes.rb to just use the resources call, since we are defining all 7 routes

    Readathon::Application.routes.draw do
  root "pages#index"

  resources :books
end

  8. Run rake and make sure everything still works

  9. Commit

    $ git add .
$ git commit -m "Cleaned up routes"

Testing required fields

  1. Create another scenario in spec/features/book_management_spec.rb

      scenario 'user tries to save invalid book' do
    visit new_book_path

    fill_in "Pages", with: "200"
    save

    expect(page).to_not have_content "successfully created"

    fill_in "Title", with: "Star Wars"
    save

    user_sees_flash_message "successfully created"
  end

  2. Run the spec

    $ rspec spec/features/book_management_spec.rb
.F

Failures:

  1) Book management user tries to save invalid book
     Failure/Error: expect(page).to_not have_content "successfully created"
       expected not to find text "successfully created" in "Books Book successfully created. Edit | Delete"
     # ./spec/features/book_management_spec.rb:28:in `block (2 levels) in <top (required)>'

Finished in 0.87525 seconds
2 examples, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:21 # Book management user tries to save invalid book

Randomized with seed 8897

  3. Let's create a unit test to just test the user validation. spec/models/user_spec.rb

    require 'spec_helper'

describe Book, "validations" do
  it "is valid when it has a title attribute" do
    book = Book.new title: "Something"
    expect(book.valid?).to be_true
  end

   it "is not valid when it is missing a title attribute" do
    book = Book.new
    expect(book.valid?).to be_false
  end
end

  4. Run your new spec

    $ rspec spec/models/book_spec.rb
.F

Failures:

  1) Book validations is not valid when it is missing a title attribute
     Failure/Error: expect(book.valid?).to be_false
       expected: false value
            got: true
     # ./spec/models/book_spec.rb:11:in `block (2 levels) in <top (required)>'

Finished in 0.01662 seconds
2 examples, 1 failure

Failed examples:

rspec ./spec/models/book_spec.rb:9 # Book validations is not valid when is missing a title attribute

Randomized with seed 16767

  5. Add validates_presence_of to your book model

    class Book < ActiveRecord::Base
  validates_presence_of :title
end

  6. Run your spec

    $ rspec spec/models/book_spec.rb
..

Finished in 0.02011 seconds
2 examples, 0 failures

Randomized with seed 1631

  7. Now add tests to make sure pages are required

    require 'spec_helper'

describe Book, "validations" do
  it "is valid when it has a title attribute" do
    book = Book.new title: "Something"
    expect(book.valid?).to be_true
  end

   it "is not valid when it is missing a title attribute" do
    book = Book.new
    expect(book.valid?).to be_false
  end

  it "is valid when it has a pages attribute" do
    book = Book.new pages: "Something"
    expect(book.valid?).to be_true
  end

  it "is not valid when it is missing a pages attribute" do
    book = Book.new
    expect(book.valid?).to be_false
  end
end

  8. Run the spec

    $ rspec spec/models/book_spec.rb
.F..

Failures:

  1) Book validations is valid when it has a pages attribute
     Failure/Error: expect(book.valid?).to be_true
       expected: true value
            got: false
     # ./spec/models/book_spec.rb:16:in `block (2 levels) in <top (required)>'

Finished in 0.02594 seconds
4 examples, 1 failure

Failed examples:

rspec ./spec/models/book_spec.rb:14 # Book validations is valid when it has a pages attribute

Randomized with seed 402

  9. Make pages required.

    class Book < ActiveRecord::Base
  validates_presence_of :title, :pages
end

  10. Run the spec.

    $ rspec spec/models/book_spec.rb
F.F.

Failures:

  1) Book validations is valid when it has a pages attribute
     Failure/Error: expect(book.valid?).to be_true
       expected: true value
            got: false
     # ./spec/models/book_spec.rb:16:in `block (2 levels) in <top (required)>'

  2) Book validations is valid when it has a title attribute
     Failure/Error: expect(book.valid?).to be_true
       expected: true value
            got: false
     # ./spec/models/book_spec.rb:6:in `block (2 levels) in <top (required)>'

Finished in 0.06586 seconds
4 examples, 2 failures

Failed examples:

rspec ./spec/models/book_spec.rb:14 # Book validations is valid when it has a pages attribute
rspec ./spec/models/book_spec.rb:4 # Book validations is valid when it has a title attribute

Randomized with seed 4768

  11. What just happened? How can we fix this?

  12. Switch to test by which fields have errors

    require 'spec_helper'

describe Book, "validations" do
  it "is valid when it has a title attribute" do
    book = Book.new title: "Something"
    book.valid?
    expect(book.errors[:title].empty?).to be_true
  end

   it "is not valid when it is missing a title attribute" do
    book = Book.new
    book.valid?
    expect(book.errors[:title].empty?).to_not be_true
  end

  it "is valid when it has a pages attribute" do
    book = Book.new pages: "Something"
    book.valid?
    expect(book.errors[:pages]).to be_empty
  end

  it "is not valid when it is missing a pages attribute" do
    book = Book.new
    book.valid?
    expect(book.errors[:pages]).to_not be_empty
  end
end

  13. Run the spec

    $ rspec spec/models/book_spec.rb
....

Finished in 0.06578 seconds
4 examples, 0 failures

Randomized with seed 53245

  14. Comment out the validates_presence_of line in app/models/book.rb and make sure it fails

  15. Comment that line back in and run the tests again and make sure it passes

  16. Run rake and see if all of the tests pass

    $ rake
/home/action/.rvm/rubies/ruby-2.0.0-p247/bin/ruby -S rspec ./spec/features/book_management_spec.rb ./spec/features/view_homepage_spec.rb ./spec/models/book_spec.rb
.......

Finished in 0.92894 seconds
7 examples, 0 failures

Randomized with seed 7570

  17. Commit

    $ git add .
$ git commit -m "Made book title and pages required"

Refactoring unit tests

Let's clean up the duplication between tests in spec/models/book_spec.rb

  1. Install shoulda-matchers in your test group of your Gemfile.

    group :test do
  gem 'shoulda-matchers'
end

  2. Bundle install

  3. Shoulda matchers allows you to change your tests in spec/models/book_spec.rb to read like this

    require 'spec_helper'

describe Book, "validations" do
  it{should validate_presence_of(:title)}
  it{should validate_presence_of(:pages)}
end

  4. Run your specs

    $ rspec spec/models/book_spec.rb
..

Finished in 0.03258 seconds
2 examples, 0 failures

Randomized with seed 54297

  5. Comment out your validates_presence_of lines in app/models/book.rb, run the tests and make sure it fails

  6. Comment back in those lines and run rake, to make sure everything still passes

  7. Commit

    $ git add .
$ git commit -m "Switched book specs to use shoulda-matchers"

Testing the book index page

  1. Create another scenario in spec/features/book_management_spec.rb

    scenario "user looks for all books" do
  # Create a few books
  # Look at the page
  # Make sure the books show up
end

  2. Add factory girl rails to your gemfile in the development,test group

    # Other gems omitted

group :development, :test do
  gem 'rspec-rails'
  gem 'capybara'
  gem 'factory_girl_rails'
end

  3. Bundle install

  4. Create your book factory spec/factories/books.rb

    FactoryGirl.define do
  factory :book do
    title "My Book"
    pages 250
  end
end

  5. Update the your spec to create some books and make sure they show up

     scenario "user looks for all books" do
    # Create a few books
    FactoryGirl.create_list :book, 3
    # Look at the page
    visit books_path
    # Make sure the books show up
    expect(page).to have_css ".book", count: 3
  end

  6. Run your spec

    $ rspec spec/features/book_management_spec.rb
F..

Failures:

  1) Book management user looks for all books
     Failure/Error: expect(page).to have_css ".book", count: 3
     Capybara::ExpectationNotMet:
       expected to find css ".book" 3 times but there were no matches
     # ./spec/features/book_management_spec.rb:41:in `block (2 levels) in <top (required)>'

Finished in 0.90766 seconds
3 examples, 1 failure

Failed examples:

rspec ./spec/features/book_management_spec.rb:35 # Book management user looks for all books

Randomized with seed 34425

  7. Update app/views/books/index.html

    <% @books.each do |book| %>
<div class="book">
  <%= book.title %>
</div>
<% end %>

  8. Run the spec

    
Failures:

  1) Book management User manages books
     Failure/Error: click_link "Books"
     ActionView::Template::Error:
       undefined method `each' for nil:NilClass
     # ./app/views/books/index.html.erb:3:in `_app_views_books_index_html_erb___3101251044140856188_22759520'
     # ./spec/features/book_management_spec.rb:6:in `block (2 levels) in <top (required)>'

  2) Book management user looks for all books
     Failure/Error: visit books_path
     ActionView::Template::Error:
       undefined method `each' for nil:NilClass
     # ./app/views/books/index.html.erb:3:in `_app_views_books_index_html_erb___3101251044140856188_22759520'
     # ./spec/features/book_management_spec.rb:39:in `block (2 levels) in <top (required)>'

Finished in 0.80397 seconds
3 examples, 2 failures

Failed examples:

rspec ./spec/features/book_management_spec.rb:4 # Book management User manages books
rspec ./spec/features/book_management_spec.rb:35 # Book management user looks for all books

Randomized with seed 19423

  9. Update the controller to assign the @books variable

    class BooksController < ApplicationController
  before_filter :find_book, only: [ :show, :edit, :update, :destroy]

  def index
    @books = Book.all
  end

# Other actions are omitted
end

  10. Run the spec

    $ rspec spec/features/book_management_spec.rb
...

Finished in 0.91608 seconds
3 examples, 0 failures

Randomized with seed 1596

  11. Commit

    $ git add .
$ git commit -m "Book index page"

  12. Refactor app/views/books/index.html.erb to use div_for helper

    <%= link_to "Add book", new_book_path %>

<% @books.each do |book| %>
  <%= div_for book do %>
    <%= book.title %>
  <% end %>
<% end %>

  13. Run specs to make sure it still passes

  14. Commit

    git add .
git commit -m "Refactored to use div_for"