Snapshot Everything

A brief introduction to the magic of "snapshot testing" (it's not just for the front-end)

Given at Brooklyn JS in 2017

Transcript

1. SNAPSHOT
   E V E R Y T H I N G
   

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2. [ BKJS SLIDE TEST ]
   (on the ceiling?)
   (unseeable)
   

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4. We do email stuff.
   

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5. Falun Copper Mine
   Sweden, 1817
   

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10. 2017 SELENIUM SURVEY
    LOVE SELENIUM
    DON’T LOVE SELENIUM
    DON’T NOT LIKE
    SELENIUM
    

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11. We use Selenium.
    We have a fuckton of tests.
    

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13. …the whole point of tests is to gain confidence
    before changing things. And to the extent that
    there are false negatives in the tests, or the
    tests gum up the works, they’re doing the
    opposite of that.
    Tests are one way to gain some confidence
    that a change is safe. But that’s all they are.
    Just one way.
    –Dan McKinley, Former Etsy Engineer
    Source: pushtrain.club
    

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14. The whole point of tests is to gain
    confidence before changing things.
    Tests are one way to gain some
    confidence that a change is safe.
    Source: Dan McKinley’s awesome slide deck at http://pushtrain.club
    

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15. snapshot
    tests!
    

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16. snapshot
    tests?
    

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24. snapshot
    tests!
    

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25. Easy to write
    Run fast
    Fail fast
    With helpful diffs
    

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26. >1200
    functional tests in our various API services
    

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43. @rhodesjason
    ſ rhodesjason
    $ npm install ohsnap
    

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44. Thanks!
    @rhodesjason
    ſ rhodesjason
    $ npm install ohsnap
    

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