Quid Est Testing?

What are the basics of testing? How do we test?

Given to the RIT Society of Software Engineers in 2009. http://sse.se.rit.edu/

Transcript

1. quid est testing?
   nick quaranto
   

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2. 5th year SE & CS major
   ruby fanatic
   bills fan
   @qrush
   litanyagainstfear.com
   

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3. http://quid.heroku.com
   

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4. what is testing?
   

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7. not:
   refreshing
   compiling
   for someone else to do
   

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8. empirical investigation conducted to provide
   stakeholders with information about the
   quality of the product or service under test
   wikipedia
   

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9. tl;dr
   

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10. the process of executing a program or system
    with the intent of finding errors
    the art of software testing
    

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11. closer...
    

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12. clean code that works
    

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13. acceptance testing
    integration testing
    functional testing
    unit testing
    

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14. acceptance testing
    integration testing
    functional testing
    unit testing
    

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15. what is a unit?
    

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16. programmer tests
    

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17. define what it means for the code to
    work
    

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18. why should I test?
    

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19. predictability
    have a process
    know you are finished
    

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20. tighter feedback loops
    running code informs decisions
    learn lessons faster
    

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21. dependability
    build trust
    know immediately when you break something
    

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22. loose coupling
    easy to test
    not just a buzzword
    

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23. how do you test?
    

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24. setup
    exercise
    verification
    teardown
    

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25. same process for any language
    test methods run in isolation
    let's do some ruby
    

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26. require 'test/unit'
    class BillsPlayerTest < Test::Unit::TestCase
    def test_to_is_a_tad_bit_hyped
    end
    end
    

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27. setup
    terrell_owens = BillsPlayer.new
    

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28. exercise
    terrell_owens.overpaid?
    

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29. verification
    assert
    

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30. other assertions
    assert_equal "wide receiver",
    terrell_owens.position
    assert_not_nil terrell_owens.number
    assert_raises InterceptionError do
    terrell_owens.miss_route!
    end
    

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31. class BillsPlayerTest < Test::Unit::TestCase
    def test_to_is_a_tad_bit_hyped
    terrell_owens = BillsPlayer.new
    assert terrell_owens.overpaid?
    end
    end
    

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32. class BillsPlayerTest < Test::Unit::TestCase
    def setup
    @terrell_owens = BillsPlayer.new
    end
    def test_to_is_a_tad_bit_hyped
    assert @terrell_owens.overpaid?
    end
    def teardown
    # bills lose, again :[
    end
    end
    

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33. so what?
    production errors due to uncomprehensive tests
    often done after the code is written
    if not automated, not preformed frequently
    and so on...
    

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34. test driven development
    

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35. you, the developer, write the tests!
    write tests before implementation
    new code only when an automated test fails
    take small steps
    

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36. the process
    write a test
    watch it fail
    write just enough code to make it pass
    

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37. let's do this
    

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38. feedback loop
    red
    green
    refactor
    

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39. refactor
    eliminate duplication
    rename
    single responsibility
    and so on...
    

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40. tdd is about design
    design is a process, not a phase
    think about the interface before
    implementation
    

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41. when do I test?
    

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42. TATFT
    

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43. the drawbacks
    

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44. all walk, no talk
    easier with a pair
    team buy-in
    

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45. some thoughts...
    

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46. it's ok not to test!
    

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47. testing vs. spiking
    

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48. dependencies
    fakes
    stubs
    mocks
    

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49. find a coop (or job) that helps you
    test
    

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50. ask about policies on testing
    

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51. TATFT
    

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