The document discusses behaviour-driven development (BDD) and automated testing. It covers test-driven development (TDD), state-based testing, interaction-based testing, using matchers to write more descriptive tests, mock objects, and integration testing. Key aspects of BDD include writing tests before code, testing at multiple levels including unit, integration and acceptance, and testing functionality from the outside-in based on specifications.

1. Behaviour-Driven Development Kerry Buckley

2. Evolution

3. Dirty Hacking

4. Automated Testing

5. Automated Testing class Adder def add a, b a + b end end class AdderTest < Test::Unit::TestCase def test_adder adder = Adder . new assert_equal 4 , adder.add( 2 , 2 ) assert_equal 2 , adder.add( 4 , - 2 ) end end

6. Are You Really Testing Your Code? class Adder def add a, b a + b end end class AdderTest < Test::Unit::TestCase def test_adder assert_equal 4 , 2 + 2 end end

7. Test-First Development

8. Test-First Development Failing tests Start Done Write code Write tests

9. Test-Driven Development

10. Test-Driven Development Failing test Clean code All tests pass Refactor

11. State-Based class DongleTest < Test::Unit::TestCase def test_wibble # Set up test inputs dongle = Dongle . new dongle.addString( &quot;foo&quot; ) dongle.addRemoteResource( &quot; http://foo.com/bar &quot; ) # Exercise functionality under test dongle.wibble! # Verify results are as expected dongle.answer.should == 42 end end

12. Bottom-Up

13. Behaviour-Driven Development

14. Behaviour-Driven Development Verification Specification State-based Interaction-based Bottom-up Outside-in Testing tool Design tool Invention Discovery

15. More Descriptive Test Names class AdderTest < Test::Unit::TestCase def test_should_add_two_positive_numbers assert_equal 4 , Adder . new .add( 2 , 2 ) end def test_should_add_a_positive_and_a_negative_number assert_equal 2 , Adder . new .add( 4 , - 2 ) end end

16. Matchers describe &quot;An adder&quot; do it &quot;should add two positive numbers&quot; do Adder . new .add( 2 , 2 ).should == 4 end it &quot;should add a positive and a negative number&quot; do Adder . new .add( 4 , - 2 ).should == 2 end end

17. Generated Documentation $ spec -f s adder_spec.rb An adder - should add two positive numbers - should add a positive and a negative number Finished in 0.005493 seconds 2 examples, 0 failures

18. More Matcher Examples @string .should == &quot;foo&quot; @array .should_not be_empty @hash .should have_key( :foo ) @object .should be_an_instance_of String lambda { @stack .pop }.should raise_error( StackUnderflowError )

19. Top-Down

20. Interaction-Based

21. Mock Objects Stand-ins for collaborating objects Mock the interface, not a specific object Verify that expected calls are made Not stubs! For your code only!

22. Classicists v Mockists

23. Mock Objects Mock Mock

24. Boundary Objects

25. Integration Testing

26. Further Reading Introducing BDD (Dan North) http: //dannorth . net/introducing-bdd BDD Introduction http: //behaviour-driven .org/Introduction Mock Roles, Not Objects (Freeman, Mackinnon, Pryce, Walnes) http://www. jmock .org/oopsla2004. pdf BDD in Ruby (Dave Astels) http: //blog . daveastels . com/files/BDD_Intro . pdf