1. RSpec
documentation
http://relishapp.com/rspec

2. components
RSpec Core
RSpec Expectations
RSpec Mocks
RSpec Rails

3. run specs
rake spec
rake spec:models
rspec spec/models/order_spec.rb
rspec spec/models/order_spec.rb:19

4. "be" matchers
describe 0 do
it { subject.zero?.should == true }
# vs.
it { should be_zero } # 0.zero? == true
end

5. have(n).items matcher
collection.should have(x).items
collection.should have_at_least(x).items
collection.should have_at_most(x).items
it { should have(5).line_items }

6. subject

7. implicit subject
describe Comment do
subject { Comment.new }
end

8. explicit subject
describe Order do
subject { Factory.build(:order) }
end

9. implicit receiver
it { subject.should be_valid }
# vs.
it { should be_valid }

10. its
its(:status_name) { should == :draft }
its('line_items.count') { should == 5 }

11. let
before do
@order = Factory.create(:shipped_order)
end
# vs.
let(:order) do
Factory.create(:shipped_order)
end

12. context vs. describe
alias :context :describe
describe is for methods
context is for contexts

13. class & instance methods
describe '#title' do # instance method
...
end
describe '.title' do # class method
...
end

14. context
context 'when quantity is negative' do
before { subject.quantity = -1 }
...
end

15. model validations
it { should be_invalid }
its(:errors) { should be_present }
it { should have(1).errors_on(:quantity) }

16. shoulda-matchers
it 'should validate email and quantity' do
subject.email = 'test@example.com'
subject.quantity = -1
subject.valid?
should have(:no).errors_on(:email)
should have_at_least(1).error_on(:quantity)
end
# vs.
it { should allow_value('test@example.com').for(:email) }
it { should_not allow_value(-1).for(:quantity) }

17. mocks
fake objects and methods
don't touch database
faster specs

18. rails model mocks
mock_model is a test double that acts like an
ActiveModel
stub_model is a instance of a real
ActiveModel with some methods stubbed

19. using mocks
let(:email_template) do
stub_model(EmailTemplate,
:name => 'test_email', ...)
end
before do
...
EmailTemplate.stub(:find_by_name).
with('test_email').
and_return(email_template)
end

20. message expectation
def should_deliver_mail(method)
Mailer.should_receive(method).
with(subject).
and_return(double(:deliver => nil))
end

21. questions?