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

1. Straight Up RSpec 3
a neat Ruby BDD tool

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

3. Organization

4. .rspec
lib/…
spec/spec_helper.rb
spec/support/matchers/drink.rb
spec/martini_spec.rb

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

6. Running Specs

7. .rspec
--color
--warnings
--require spec_helper
.rspec

8. .rspec-local
—-format documentation
--backtrace
.rspec-local

9. $ rspec spec/martini_spec.rb:15:22

10. $ rspec --format documentation

11. $ rspec --fail-fast

12. $ rspec --tag js:true

13. $ rspec --profile
…
!
Top 10 slowest examples (0.00226 seconds, 57.2% of total time):
Martini with a mixer #ingredients should include "vermouth"
0.00058 seconds ./spec/martini_spec.rb:15
InitializeWithAttrsSpec with attributes #pages should eq 123
0.00052 seconds ./spec/initialize_with_attrs_spec.rb:16
…

14. $ rspec --order random
…
Randomized with seed 63958

15. $ rspec --order random:63958

16. martini_spec.rb
describe "Martini" do
…
it "should have ingredients", :focus do
expect(martini).to respond_to(:ingredients)
end
…
end
:focus

17. martini_spec.rb
describe "Martini" do
…
fit "should have ingredients" do
expect(martini).to respond_to(:ingredients)
end
…
end
fit

18. martini_spec.rb
describe "Martini" do
…
it "should have ingredients", :skip do
expect(martini).to respond_to(:ingredients)
end
…
end
:skip

19. martini_spec.rb
describe "Martini" do
…
xit "should have ingredients" do
expect(martini).to respond_to(:ingredients)
end
…
end
xit

20. martini_spec.rb
describe "Martini" do
…
pending "should have price" do
expect(@martini).to be_pricey
end
…
end
pending

21. Configuration

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

23. support/configure.rb
RSpec.configure do |c|
c.before(:suite) {} # once
c.before(:context) {} # once before each group
c.before(:example) {} # once before each example
!
c.after(:example) {} # once after each example
c.after(:context) {} # once after each group
c.after(:suite) {} # once
!
# run before each example of type :model
config.before(:example, :type => :model) {}
end
RSpec.configure

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

25. support/configure.rb
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 => 2.1 do
# ....
Exclusion

26. Barkeep
github.com/gsterndale/barkeep
an upgrade & refactoring exercise

27. martini_spec.rb
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
Original Martini 2.X Spec

28. martini_spec.rb
describe "Barkeep::Martini" do
before do
@martini = Barkeep::Martini.new
end
it "should have an attribute named booze" do
expect(@martini).to respond_to(:booze)
expect(@martini).to respond_to(:booze=)
end
it "should have an attribute named garnish" do
expect(@martini).to respond_to(:garnish)
expect(@martini).to respond_to(:garnish=)
end
end
Martini Spec 3.0

29. have_attribute.rb
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
Custom Matcher

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

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

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

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

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

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

36. have_attribute.rb
module AttributeMatchers
…
end
!
RSpec.configure do |config|
config.include AttributeMatchers
end
config.include()

37. martini_spec.rb
describe Barkeep::Martini do
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:garnish) }
end
config.include()

38. martini_spec.rb
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
Original Martini 2.X Spec

39. martini_spec.rb
describe Barkeep::Martini do
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:garnish) }
end
Refactored Martini 3.0 Spec

40. whiskey_spec.rb
describe Barkeep::Whiskey do
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:glass) }
end
New Whiskey Spec

41. martini_spec.rb
describe Barkeep::Martini do
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:glass) }
it { is_expected.to have_attribute(:garnish) }
end
Additions to Martini Spec

42. support/examples/drink.rb
shared_examples_for "a drink" do
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:glass) }
end
Shared Example Group

43. whiskey_spec.rb
describe Barkeep::Whiskey do
it_behaves_like "a drink"
end
Whiskey Spec

44. whiskey_spec.rb
describe Barkeep::Whiskey do
include_examples "a drink"
end
Whiskey Spec

45. martini_spec.rb
describe Barkeep::Martini do
it_behaves_like "a drink"
it { is_expected.to have_attribute(:garnish) }
end
Martini Spec

46. support/examples/drink.rb
shared_examples_for "a drink" do |ingredients|
it { is_expected.to have_attribute(:booze) }
it { is_expected.to have_attribute(:glass) }
!
describe "#ingredients" do
subject { super().ingredients }
it { is_expected.to be_a Array }
it { is_expected to include *ingredients }
end
end
Whiskey & Martini #ingredients

47. martini_spec.rb
describe Barkeep::Martini do
it_behaves_like "a drink", "vodka"
it { is_expected.to have_attribute(:garnish) }
end
Martini Spec

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

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

50. martini_spec.rb
describe Barkeep::Martini do
it_behaves_like "a drink"
it { is_expected.to have_attribute(:garnish) }
it { is_expected.to have_attribute(:mixer) }
context "with a mixer" do
let(:mixer) { 'vermouth' }
before { subject.mixer = mixer }
!
its(:ingredients) { is_expected.to
include mixer }
end
end
its()

51. martini_spec.rb
describe Barkeep::Martini do
it_behaves_like "a drink"
it { is_expected.to have_attribute(:garnish) }
it { is_expected.to have_attribute(:mixer) }
end
!
describe Barkeep::Martini, ".new with mixer" do
let(:mixer) { 'vermouth' }
subject { Barkeep::Martini.new(mixer: mixer) }
its(:ingredients) { is_expected.to include mixer }
end
its()

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

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

54. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to include
'juice', 'vodka', 'olives', 'vermouth' }
!
it { is_expected.to contain_exactly
'vodka', 'vermouth', 'juice', 'olives' }
end
Array Matchers

55. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to start_with 'vodka' }
it { is_expected.to end_with 'olives' }
end
Array Matchers

56. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to all be_a(String) }
it { is_expected.to all start_with(/^w/) }
end
Array Matchers

57. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to all
be_a(String) & start_with(/^w/) }
end
Compound Matchers

58. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to match [
start_with(/^w/),
match(/olives?/)
] }
end
Composable Matchers

59. martini_spec.rb
describe Barkeep::Martini, ".dirty" do
let(:martini) { Barkeep::Martini.dirty }
subject { martini.ingredients }
!
it { is_expected.to match [
a_string_starting_with(/^w/),
a_string_matching(/olives?/)
] }
end
Composable Matchers

60. terminal_spec.rb
describe Terminal, "#printer" do
let(:epson) { stub "Espon 5000" }
let(:terminal) { Terminal.new(:ip => "1.1.1.1") }
subject { terminal.printer }
!
before do
Printer.stub(:by_ip).and_return(epson)
end
!
it { should eq epson }
end
RSpec 2.X doubles

61. terminal_spec.rb
describe Terminal, "#printer" do
let(:epson) { double "Espon 5000" }
let(:terminal) { Terminal.new(:ip => "1.1.1.1") }
subject { terminal.printer }
!
before do
allow(Printer).to receive_messages(by_ip: epson)
end
!
it { is_expected.to eq epson }
end
RSpec 3.0 doubles

62. terminal_spec.rb
describe Terminal, "#printer" do
let(:epson) { double "Espon 5000" }
let(:terminal) { Terminal.new(:ip => "1.1.1.1") }
subject { terminal.printer }
!
before do
allow(Printer).to receive_messages(by_ID: epson)
end
!
it { is_expected.to eq epson }
end
Double checking™

63. terminal_spec.rb
describe Terminal, "#printer" do
let(:epson) { stub "Espon 5000" }
let(:terminal) { Terminal.new(:ip => "1.1.1.1") }
subject { terminal.printer }
!
before do
Printer.should_receive(:by_ip)
.with("1.1.1.1").and_return(epson)
end
!
it { should eq epson }
end
RSpec 2.X message expectation

64. terminal_spec.rb
describe Terminal, "#printer" do
let(:epson) { double "Espon 5000" }
let(:terminal) { Terminal.new(:ip => "1.1.1.1") }
before do
allow(Printer).to receive_messages(by_ip: epson)
end
subject! { terminal.printer }
!
it { is_expected.to eq epson }
it "finds printer by IP" do
expect(Printer).to
have_received(:by_ip).with("1.1.1.1")
end
RSpec 3.0 message expectation

65. Links

66. support/configure.rb
Its:
github.com/rspec/rspec-its
!
Collection Matchers:
github.com/rspec/rspec-collection_matchers
!
RSpec Rails:
github.com/rspec/rspec-rails
!
ActiveModel mocks:
github.com/rspec/rspec-activemodel-mocks
Libraries

67. support/configure.rb
Step-by-step upgrade instructions:
relishapp.com/rspec/docs/upgrade
!
RDoc:
rubydoc.info/github/rspec/rspec-expectations
!
Features as documentation:
relishapp.com/rspec
Documentation

68. support/configure.rb
Transpec, the RSpec syntax conversion tool:
yujinakayama.me/transpec/
!
Myron Marston’s blog:
myronmars.to
Resources

69. CHEERS

70. spec/user_spec.rb
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
let() gotcha

71. spec/user_spec.rb
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
let() work-around

72. spec/user_spec.rb
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
let!()