Going beyond the basics, introducing some elegant features and promoting readability.

1. Straight Up RSpec
a neat Ruby BDD tool

2. The Menu
Organization $0
Options $0
Refactoring Exercise $0
Configuration $0
Other Libraries $0

3. Organization

4. .rspec
lib/barkeep.rb
lib/barkeep/martini.rb
spec/spec_helper.rb
spec/support/configure.rb
spec/support/matchers/drink.rb
spec/martini_spec.rb

5. spec_helper
require 'rspec'
require 'barkeep'
Dir["#{File.dirname(__FILE__)}/support/**/*.rb"].
each {|file| require file }
spec_helper.rb

6. Options

7. $ rspec spec -f documentation

8. $ rspec spec/martini_spec.rb -l 16

9. $ rspec spec -t slow

10. Barkeep
github.com/gsterndale/barkeep
a refactoring exercise

11. Martini Spec Draft
describe "Barkeep::Martini" do
before do
@martini = Barkeep::Martini.new
end
it "should have an attribute named booze" do
@martini.should respond_to(:booze)
@martini.should respond_to(:booze=)
end
it "should have an attribute named garnish" do
@martini.should respond_to(:garnish)
@martini.should respond_to(:garnish=)
end
end
martini_spec.rb

12. Custom Matcher
module AttributeMatchers
Spec::Matchers.define :have_attribute do |name|
match do |target|
getter = name.to_sym
setter = (name.to_s + "=").to_sym
target.respond_to?(getter) &&
target.respond_to?(setter)
end
end
end
have_attribute.rb

13. Custom Matcher
describe "Barkeep::Martini" do
include AttributeMatchers
before do
@martini = Barkeep::Martini.new
end
it "should have an attribute named booze" do
@martini.should have_attribute(:booze)
end
it "should have an attribute named garnish" do
@martini.should have_attribute(:garnish)
end
end
martini_spec.rb

14. subject()
describe "Barkeep::Martini" do
include AttributeMatchers
subject { Barkeep::Martini.new }
it "should have an attribute named booze" do
subject.should have_attribute(:booze)
end
it "should have an attribute named garnish" do
subject.should have_attribute(:garnish)
end
end
martini_spec.rb

15. Implicit subject()
describe "Barkeep::Martini" do
include AttributeMatchers
subject { Barkeep::Martini.new }
it "should have an attribute named booze" do
should have_attribute(:booze)
end
it "should have an attribute named garnish" do
should have_attribute(:garnish)
end
end
martini_spec.rb

16. DRY Messages
describe "Barkeep::Martini" do
include AttributeMatchers
subject { Barkeep::Martini.new }
it { should have_attribute(:booze) }
it { should have_attribute(:garnish) }
end
martini_spec.rb

17. Derived subject()
describe Barkeep::Martini do
include AttributeMatchers
it { should have_attribute(:booze) }
it { should have_attribute(:garnish) }
end
martini_spec.rb

18. config.include()
RSpec.configure do |config|
config.include AttributeMatchers
end
support/configure.rb

19. config.include()
describe Barkeep::Martini do
it { should have_attribute(:booze) }
it { should have_attribute(:garnish) }
end
martini_spec.rb

20. Original Draft
describe "Barkeep::Martini" do
before do
@martini = Barkeep::Martini.new
end
it "should have an attribute named booze" do
@martini.should respond_to(:booze)
@martini.should respond_to(:booze=)
end
it "should have an attribute named garnish" do
@martini.should respond_to(:garnish)
@martini.should respond_to(:garnish=)
end
end
martini_spec.rb

21. Whiskey Spec
describe Barkeep::Whiskey do
it { should have_attribute(:booze) }
it { should have_attribute(:glass) }
end
whiskey_spec.rb

22. Martini Spec
describe Barkeep::Martini do
it { should have_attribute(:booze) }
it { should have_attribute(:glass) }
it { should have_attribute(:garnish) }
end
martini_spec.rb

23. Shared Example Group
share_examples_for "a drink" do
it { should have_attribute(:booze) }
it { should have_attribute(:glass) }
end
support/examples/drink.rb

24. Whiskey Spec
describe Barkeep::Whiskey do
it_should_behave_like "a drink"
end
whiskey_spec.rb

25. Martini Spec
describe Barkeep::Martini do
it_should_behave_like "a drink"
it { should have_attribute(:garnish) }
end
martini_spec.rb

26. Whiskey & Martini #ingredients
share_examples_for "a drink" do
it { should have_attribute(:booze) }
it { should have_attribute(:glass) }
it "should have an ingredients Array" do
subject.ingredients.should be_a Array
end
end
support/examples/drink.rb

27. context()
describe Barkeep::Martini do
it_should_behave_like "a drink"
it { should have_attribute(:garnish) }
it { should have_attribute(:mixer) }
context "with a mixer" do
before do
@mixer = 'vermouth'
subject.mixer = @mixer
end
it "should include mixer in ingredients" do
subject.ingredients.should include @mixer
end
end
martini_spec.rb

28. let()
describe Barkeep::Martini do
it_should_behave_like "a drink"
it { should have_attribute(:garnish) }
it { should have_attribute(:mixer) }
context "with a mixer" do
let(:mixer) { 'vermouth' }
before { subject.mixer = mixer }
it "should include mixer in ingredients" do
subject.ingredients.should include mixer
end
end
end
martini_spec.rb

29. its()
describe Barkeep::Martini do
it_should_behave_like "a drink"
it { should have_attribute(:garnish) }
it { should have_attribute(:mixer) }
context "with a mixer" do
let(:mixer) { 'vermouth' }
before { subject.mixer = mixer }
its(:ingredients) { should include mixer }
end
end
martini_spec.rb

30. its()
describe Barkeep::Martini do
it_should_behave_like "a drink"
it { should have_attribute(:garnish) }
it { should have_attribute(:mixer) }
end
describe Barkeep::Martini, ".new with mixer" do
let(:mixer) { 'vermouth' }
subject { Barkeep::Martini.new(:mixer => mixer) }
its(:ingredients) { should include mixer }
end
martini_spec.rb

31. have()
describe Barkeep::Martini, ".new with mixer" do
let(:mixer) { 'vermouth' }
subject { Barkeep::Martini.new(:mixer => mixer) }
its(:ingredients) { should include mixer }
its(:ingredients) { should have(1).items }
end
martini_spec.rb

32. have()
describe Barkeep::Martini, ".new with mixer" do
let(:mixer) { 'vermouth' }
subject { Barkeep::Martini.new(:mixer => mixer) }
its(:ingredients) { should include mixer }
it { should have(1).ingredients }
end
martini_spec.rb

33. expect()
describe Barkeep::Martini do
let(:mixer) { 'vermouth' }
it "should include mixer in ingredients" do
expect { subject.mixer = mixer }.
to change { subject.ingredients }.
from( [] ).
to [ mixer ]
end
end
martini_spec.rb

34. stub()
describe Barkeep::Terminal, "#printer" do
let(:ones) { "1.1.1.1" }
let(:epson) { double("Espon 5000") }
subject { Barkeep::Terminal.new(:ip => ones) }
before do
Printer.stub(:new) { epson }
end
it "should have a printer" do
subject.printer.should eq epson
end
end
terminal_spec.rb

35. should_receive()
describe Barkeep::Terminal, "#printer" do
let(:ones) { "1.1.1.1" }
let(:epson) { double("Espon 5000") }
subject { Barkeep::Terminal.new(:ip => ones) }
it "should have a printer" do
Printer.should_receive(:new).
with(:ip => ones) { epson }
subject.printer
end
end
terminal_spec.rb

36. Configuration

37. RSpec.configure
RSpec.configure do |config|
config.include MyMartiniMatchers
config.include ModelHelpers, :type => :model
end
# spec/model/martini_spec.rb
describe Martini, :type => :model do
…
end
support/configure.rb

38. RSpec.configure
RSpec.configure do |config|
config.before(:all) {} # run once
config.before(:each) {} # run before each example
config.after (:each) {} # run after each example
config.after (:all) {} # run once
# run before each example of type :model
config.before(:each, :type => :model) {}
end
support/configure.rb

39. Inclusion
RSpec.configure do |c|
c.filter_run :focus => true
c.run_all_when_everything_filtered = true
end
# in any spec file
describe "something" do
it "does something", :focus => true do
# ....
end
end
support/configure.rb

40. Exclusion
RSpec.configure do |c|
c.exclusion_filter = { :ruby => lambda {|version|
!(RUBY_VERSION.to_s =~ /^#{version.to_s}/)
}}
end
# in any spec file
describe "something" do
it "does something", :ruby => 1.8 do
# ....
end
it "does something", :ruby => 1.9 do
# ....
support/configure.rb

41. Other Libraries

42. RSpec::Rails

43. response.should redirect_to("some/url")
response.should be_success
response.should have_tag("div", "some text")

44. Shoulda::Matchers

45. describe User do
it { should belong_to(:account) }
it { should have_many(:posts) }
it { should validate_presence_of(:email) }
it { should allow_value("f@b.com").for(:email) }
it { should_not allow_value("test").for(:email) }
end

46. CHEERS

47. let() gotcha
describe User, ".admin_names" do
let(:admin) { User.create!(:admin => true,
:first => "Clark",
:last => "Kent")}
let(:avg_joe) { User.create!(:admin => false,
:first => "Joe",
:last => "Shmo")}
subject { admin_names }
it { should include "Clark Kent" }
it { should_not include "Joe Shmo" }
end
spec/user_spec.rb

48. let() work-around
describe User, ".admin_names" do
let(:admin) { User.create!(:admin => true,
:first => "Clark",
:last => "Kent")}
let(:avg_joe) { User.create!(:admin => false,
:first => "Joe",
:last => "Shmo")}
subject { User.admin_names }
before { admin && avg_joe }
it { should include "Clark Kent" }
it { should_not include "Joe Shmo" }
end
spec/user_spec.rb

49. let!()
describe User, ".admin_names" do
let!(:admin) { User.create!(:admin => true,
:first => "Clark",
:last => "Kent")}
let!(:avg_joe) { User.create!(:admin => false,
:first => "Joe",
:last => "Shmo")}
subject { User.admin_names }
it { should include "Clark Kent" }
it { should_not include "Joe Shmo" }
end
spec/user_spec.rb