Unit testing

Talk about Unit Testing: Pet / Cin / Universidade Federal de Pernambuco.
https://www.facebook.com/events/372202459624692/

Cloning and running tests on senna https://asciinema.org/a/14458

Transcript

1. Unit testing Henrique Vicente

   henvic.github.io
   

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3. Why
   • Legacy code = code without tests
   • Safety net = fewer defects
   • Test cases = free and up-to-date docs
   • Prove that your code works
   • Ensure changes don’t break a thing
   

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4. Test-Driven Development
   • Programming technique
   • Part of Agile methodologies, including XP
   

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5. Write failing
   test case
   Verify all
   tests pass
   Change
   code
   

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7. Challenges
   • Lack of company culture
   • Legacy code
   • Code coverage
   • Experimenting
   • Dependencies
   • Data providers
   • Nondeterministic algorithms
   

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8. Unit tests
   • Independent from each other
   • Runs damn fast (ms to seconds)
   • Essential if you decide to use TDD
   • Don’t test private methods, cover it indirectly
   

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9. Mocks
   • Isolate dependencies by mocking
   • Dependency injection / inversion of control to the
   rescue!
   

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10. Data provider
    • Mock your data
    • Unit tests shouldn’t talk with SQL databases,
    remote procedures, and so on.
    

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11. www.mockaroo.com
    

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12. Integration testing
    • Testing of your unit tests in conjunction
    • Testing several production code
    

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13. Continuous Integration
    • Not to be confused with integration testing
    • Useful for integration testing
    • Let your developers know the status of your
    software builds
    

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14. build status
    

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20. Java HelloWorldTest
    

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23. Run the unit test here!
    

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29. It’ll ask you to
    accept license and,
    once installed, to
    restart Eclipse.
    

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30. Run the coverage!
    http://www.eclemma.org/faq.html
    

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31. Bad loop, but covered
    

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32. Why are JUnit4 test cases with
    expected exceptions shown as
    not covered?
    http://www.eclemma.org/faq.html
    

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33. KISS
    Keep ignoring.
    Refactor!
    

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36. JUnit tests annotations
    • @Test
    • @Before
    • @After
    • @BeforeClass
    • @AfterClass
    • @Ignore
    

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37. JUnit asserts
    • void assertEquals(boolean expected, boolean actual)
    • void assertTrue(boolean expected, boolean actual)
    • void assertFalse(boolean condition)
    • void assertNotNull(Object object)
    • void assertNull(Object object)
    • void assertSame(boolean condition)
    • void assertNotSame(boolean condition)
    • void assertArrayEquals(expectedArray, resultArray);
    

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38. http://docs.travis-ci.com/user/languages/java/
    

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39. https://github.com/mplacona/java-junit-template-project
    

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40. JavaScript helloWorld()
    • Client? Server?
    • Mocha
    • Karma
    • many others
    

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41. Continuous Integration
    • Travis
    • Jenkins
    • others
    

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42. • pre-commit to abort commits
    without —no-verify
    • post-commit to give you an
    opportunity to —amend before
    pushing to a remote.
    

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46. https://travis-ci.org/eduardolundgren/senna/builds/40133436
    

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50. https://github.com/caolan/nodeunit
    

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52. http://karma-runner.github.io/
    

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54. https://asciinema.org/a/14458
    

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55. • A Virtual Conference for Developers http://hacksummit.org/
    • http://en.wikipedia.org/wiki/File:Wistar_rat.jpg
    • OMG PONIES!!! (AKA HUMANITY: EPIC FAIL)

    http://codeblog.jonskeet.uk/2009/11/02/omg-ponies-aka-humanity-epic-fail/ or Jon Skeet’s
    video at hack.summit
    • http://en.wikipedia.org/wiki/File:Test-driven_development.PNG
    • http://www.zyracuze.com/for-your-information/kiss-keep-it-simple-stupid/
    • Watch Uncle Bob (Robert Martin) videos, read his Code Clean and Coder Clean books, and
    if you have to deal with legacy code, try Working Effectively with Legacy Code.
    

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