BDD with Cucumber and RSpec. Marcus Ahnve Valtech AB marcus.ahnve@valtech.se @mahnve

BDD with Cucumber and RSpec Marcus Ahnve Valtech AB marcus.ahnve@valtech.se @mahnve

Software Developer Polyglot Programmer About me

Q: How many are using Cucumber

Q: How many have heard of Cucumber

Q: How many are using RSpec

Q: How many have heard of RSpec

Q: How many are doing TDD/BDD?

Q: How many think I am asking too many questions?

My BDD history Java and Ruby developer TestDox, Joe Walnes Dan North Dave Astels, Aslak Hellesøy, David Chelimsky

$ rake Finished in 27.79 seconds 285 examples, 0 failures 152 scenarios (152 passed) 1363 steps (1363 passed) 4m4.505s Finished in 8.06 seconds 77 examples, 0 failures

Why automatic testing? Make sure it works now Make sure it works whenever

Why TDD? Make sure it works now Make sure it works whenever Know when you're done

Method Testing class Klazz def method do_something end end class KlazzTest def setup @klazz = Klazz.new end def test_method result = @klazz.do_something assert_equal("expected", result) end end

The Context Problem class KlazzTest def setup @klazz = Klazz.new end def test_method result = @klazz.do_something assert_equal(:expected, result) end def test_another_context klazz = Klazz.new(:constructor_args) assert_equal(:expected_2, klazz.do_something) end end

Why BDD? Make sure it works now Make sure it works whenever Know when you're done Build just what's needed Design from functionality Documentation - why

What is BDD? "BDD is TDD done right" "TDD means 'write the test first'. BDD takes this idea to a more general level: 'write the client first' (the outside)" - Aslak Hellesøy

The BDD Flow Write a failing feature Implement feature 0.. * Implement spec Write a failing spec

$ rails new blog -T create create README create Rakefile create config.ru create.gitignore create Gemfile create app create app/controllers/application_controller.rb... create vendor/plugins/.gitkeep

source 'http://rubygems.org' gem 'rails', '3.0.0' gem 'sqlite3-ruby', :require => 'sqlite3' group :test do gem 'rspec-rails' gem 'cucumber-rails' gem 'capybara' end

$ bundle install master(mon,apr04) Fetching source index for http://rubygems.org/ Using rake (0.8.7)... Installing rack (1.2.2) Installing rack-mount (0.6.14)... Installing gherkin (2.3.5) with native extensions Installing term-ansicolor (1.0.5) Installing cucumber (0.10.2) Installing cucumber-rails (0.4.0)... Installing rspec (2.5.0) Installing rspec-rails (2.5.0) Using sqlite3 (1.3.3) Using sqlite3-ruby (1.3.3)

$ rake db:migrate

$ rails generate cucumber:install create config/cucumber.yml create script/cucumber chmod script/cucumber create features/step_definitions create features/step_definitions/web_steps.rb create features/support create features/support/paths.rb create features/support/selectors.rb create features/support/env.rb exist lib/tasks create lib/tasks/cucumber.rake gsub config/database.yml gsub config/database.yml force config/database.yml

$ rails generate rspec:install master(mon,apr04) create.rspec create spec create spec/spec_helper.rb

Feature: User writes blog post In order for other people to read brilliant thoughts A user can post a blog post Scenario: Given I am on the new blog post page When I write a blog post And it has the title "My great Idea" And it has the body "Body body body" And I press "Save" Then I should see "My great Idea"

$ rake 1 scenario (1 failed) 6 steps (1 failed, 2 skipped, 3 undefined) 0m1.103s You can implement step definitions for undefined steps with these snippets:

When /^I write a blog post$/ do pending # express the regexp above with the code you wish you had end When /^it has the title "([^"]*)"$/ do arg1 pending # express the regexp above with the code you wish you had end When /^it has the body "([^"]*)"$/ do arg1 pending # express the regexp above with the code you wish you had end

$ rake Given I am on the new blog post page # features/step_definitions/web_steps.rb:44 Can't find mapping from "the new blog post page" to a path. Now, go and add a mapping in /home/mahnve/src/presentations/cucumber/src/blog/features/su

module NavigationHelpers def path_to(page_name) case page_name when /the home\s?page/ '/' when /the new blog post page/ '/blog_posts/new'

$ rake Scenario: # features/user_writes_blogpost.feature:6 Given I am on the new blog post page # features/step_definitions/web_steps.rb:44 No route matches "/blogpost/new" (ActionController::RoutingError)

$ rails generate resource BlogPost title:string body:string invoke active_record create db/migrate/20110404155134_create_blog_posts.rb create app/models/blog_post.rb invoke test_unit create test/unit/blog_post_test.rb create test/fixtures/blog_posts.yml invoke controller create app/controllers/blog_posts_controller.rb invoke erb create app/views/blog_posts invoke test_unit create test/functional/blog_posts_controller_test.rb invoke helper create app/helpers/blog_posts_helper.rb invoke test_unit create test/unit/helpers/blog_posts_helper_test.rb route resources :blog_posts

$ rake (in /home/mahnve/src/presentations/cucumber/src/blog) You have 1 pending migrations: 20110404155134 CreateBlogPosts

class CreateBlogPosts < ActiveRecord::Migration def self.up create_table :blog_posts do t t.string :title t.string :body t.timestamps end end def self.down drop_table :blog_posts end end

$ rake db:migrate (in /home/mahnve/src/presentations/cucumber/src/blog) == CreateBlogPosts: migrating ====================================== -- create_table(:blog_posts) -> 0.0010s == CreateBlogPosts: migrated (0.0010s) ================================

$ rake Given I am on the new blog post page # features/step_definitions/web_steps.rb:44 The action 'new' could not be found for BlogPostsController (AbstractController::ActionNotFound

gem 'inherited_resources'

class BlogPostsController < InheritedResources::Base end

$ rake Missing template blog_posts/new with...

gem 'formtastic' gem 'haml'

- semantic_form_for @blog_post do form = form.inputs = form.buttons

$ rake Given I am on the new blog post page # features/step_definitions/web_steps.rb:44 When I write a blog post # features/step_definitions/blogpost_steps.rb:1 TODO (Cucumber::Pending)./features/step_definitions/blogpost_steps.rb:2:in `/^I write a blog post$/'

Oops Steps where not really optimal

When /^I write a blog post with title "([^"]*)" and the body "([^"]*)"$/ do fill_in 'Title', :with => title fill_in 'Body', :with => body end

Given I am on the new blog post page When I write a blog post with title "My great Idea" and body "Body body body" And I press "Create Blog post" Then I should see "My great Idea"

$ rake... Missing template blog_posts/show

= @blog_post.title

Scenario: Create without title Given I am on the new blog post page When I write a blog post without a title And I press "Create Blog post" Then I should see "can't be blank"

$ rake Then I should see "Required" # features/step_definitions/web_steps.rb:105 expected #has_content?("required") to return true, got false (RSpec::Expectations::Expectatio

require 'spec_helper' describe BlogPost do it {should validate_presence_of :title} end

group :test, :development do gem 'rspec-rails' end group :test do gem 'cucumber-rails' gem 'capybara' gem 'database_cleaner' gem 'shoulda-matchers' end

$ rake 1) BlogPost Failure/Error: it {should validate_presence_of :title} Expected errors to include "can't be blank" when title is set to nil, got no errors

class BlogPost < ActiveRecord::Base validates_presence_of :title end

$ rake. Finished in 0.02658 seconds 1 example, 0 failures 2 scenarios (2 passed) 8 steps (8 passed) 0m1.084s

Java package cukes; import cuke4duke.annotation.i18n.en.given; public class BlogPostSteps { @Given("^I write a blog post with title \\"([^\\"]*)\\" and body \\"([^\\"]*)\\ public void writeblogpost (String title, String body) {... } }

Groovy this.metaclass.mixin(cuke4duke.groovydsl) Given(~/^I write a blog post with title "([^"]*)" and body "([^"]*)"$/) { String title, String body... }

Thank You!