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Have you ever tested your tests?

Sponsored · Ship Features Fearlessly Turn features on and off without deploys. Used by thousands of Ruby developers. →
Avatar for Rafael Machado Rafael Machado
November 09, 2019
Programming
120
2

Have you ever tested your tests?

Avatar for Rafael Machado

Rafael Machado

November 09, 2019

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Transcript

  1. HAVE YOU EVER TESTED YOUR TESTS?

  2. Henrique Morbin iOS @ Consumer

  3. Rafael Machado iOS @ Driver

  4. AGENDA 1. SOFTWARE QUALITY & METRICS 2. CODE COVERAGE 3.

    MUTATION TESTING 4.MUTER: AUTOMATED MUTATION TESTING FOR SWIFT

  5. SOFTWARE QUALITY & METRICS

  6. CODE COVERAGE

  7. None

  8. class Tests: XCTestCase { func test_view() { let sut =

    ViewController(presenter: .dummy) XCTAssertNotNil(sut.view) } }

  9. 55% VALIDATION

  10. COVERAGE ISN’T EVERYTHING

  11. ?

  12. MUTATION TESTING

  13. HOW DOES IT WORK?

  14. None
  15. None
  16. None

  17. MUTATION SCORE = Mutants killed Total of mutants

  18. MUTATION OPERATORS

  19. None

  20. C# JAVASCRIPT JAVA PYTHON SWIFT C/C++ OBJECTIVE-C

  21. Muter Automated mutation testing for Swift

  22. DISCOVERY TESTS REPORT

  23. None

  24. $ muter init

  25. !// muter.conf.json { "executable": “/usr/bin/xcodebuild", "arguments": [ "-project", "ExampleApp.xcodeproj", "-scheme",

    "ExampleApp", "-sdk", "iphonesimulator", "-destination", "platform=iOS Simulator,name=iPhone 8", "test" ], "exclude": ["AppDelegate.swift"] }

  26. $ muter

  27. $ muter —output-xcode

  28. None

  29. $ muter —files-to-mutate "/Sources/**/*.swift"

  30. $ muter —files-to-mutate \ $(echo \"$(git diff "--name-only HEAD HEAD~1

    | tr '\n' ‘,')\")

  31. RECAP COVERAGE ISN’T EVERYTHING PAPERS HIGH COST MUTATION SCORE FEW

    OPERATORS ARE ENOUGH

  32. THANK YOU

  33. #VemProiFood