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Property-based testing: The lazy programmer's g...

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Avatar for Pierre GOUDJO Pierre GOUDJO
January 20, 2022
Programming
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Property-based testing: The lazy programmer's guide to writing thousands of tests

Avatar for Pierre GOUDJO

Pierre GOUDJO

January 20, 2022

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Transcript

  1. Pierre Goudjo Property-based testing The lazy programmer's guide to writing

    thousands of tests

  2. “Real-life” Scenario

  3. None
  4. None
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  7. None
  8. None
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  11. None
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  25. None

  26. Solution

  27. What’s an addition?

  28. None
  29. None

  30. Properties Addition • Associativity: x+(y+z) = (x+y)+z • Commutativity: x

    + y = y + x • Identity Element: x+0 = x

  31. This is property-based testing

  32. for any (x, y, …) such as precondition(x, y, …)

    holds property(x, y, …) is true

  33. Let’s implement this!!!!

  34. Is it useful?

  35. Avg • for any number (a and b ) •

    such a <= b • a <= avg(a, b) and avg(a, b) <= b • for any number (a and b ) • such a <= b • avg(a, b) == avg(a, b)

  36. Zip/Unzip • for any string (x) • such as x

    not “” • unzip(zip(x)) == x is true