Snapshot testing (nomadphp)

Transcript

1. A practical intro to
   snapshot testing
   

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2. About me
   Freek Van der Herten
   Partner & developer at SPATIE
   @freekmurze
   https://murze.be
   

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3. About me
   phpantwerp.be
   Dries Vints
   @driesvints
   Frederick Vanbrabant
   @TheEdonian
   

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4. Since 2003
   Websites, applications and webshops
   Team
   4 developers, 1 manager
   Specialization
   Laravel development
   

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5. OPEN SOURCE SOFTWARE
   

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6. ± 120 packages on Packagist
   Laravel, Framework agnostic PHP
   ± 4 000 000 downloads in total, growing ±500 000 a month
   We create a lot of it
   Open source software
   

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7. http://github-awards.com/users?type=world&language=php
   Open source software
   

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8. LET’S TALK SNAPSHOT TESTING
   

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9. A file on disk, let’s call in snapshot
   Test succeeds if output matches snapshot
   If not, test will fail
   What?
   

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10. Old name: characterization testing
    Popularized by Facebook
    Jest
    Testing interfaces
    Where does it come from?
    

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11. https://github.com/spatie/phpunit-snapshot-assertions
    assertMatchesSnapshot
    assertMatchesJsonSnapshot
    assertMatchesXmlSnapshot
    How can we do it in PHP?
    

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12. DEMO
    

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13. WRAPPING UP
    

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14. Advantages
    Very easy to get started with
    Can be used to validate complex output
    Easily update all the tests in one go
    

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15. Disadvantages
    Brittle
    Hard to pinpoint exact point of failure
    Bugs can be easily written in the snapshots
    

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16. https://github.com/spatie/phpunit-snapshot-assertions
    https://sebastiandedeyne.com/posts/2017/a-package-for-snapshot-
    testing-in-phpunit
    https://murze.be/2017/04/practical-introduction-snapshot-testing/
    https://www.sitepoint.com/snapshot-testing-viable-php/
    https://facebook.github.io/jest/docs/snapshot-testing.html
    Interesting links
    

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17. Thank you!
    https://speakerdeck.com/freekmurze/snapshot-testing-nomadphp
    https://spatie.be/opensource
    https://murze.be
    https://murze.be/newsletter/
    

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18. QUESTIONS?
    

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