JS Software testing for beginners

Transcript

1. Software testing with
   JavaScript_
   a quick guide
   

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2. who am I_
   {twitter, youtube, linkedin…}.lsantos.dev
   software engineer_
   hello@lsantos.dev
   

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3. software testing
   

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4. software tests are
   untested software that
   tests your software
   

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5. why?
   

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6. why automated testing?
   ➔ Improves software quality
   ➔ Prevent errors before they're published
   ➔ Builds trust in the codebase
   ◆ Changes can be published faster
   

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7. tests should be
   ➔ Deterministic
   ➔ Self-contained
   ➔ Predictable
   ➔ Small
   

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8. What to test?
   

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9. Functionality
   

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10. What not to test?
    

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11. Implementation
    

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12. let's hack!
    

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13. test runners_
    giving us an edge on tests
    

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14. let's hack!
    

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15. test doubles_
    

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16. Types of doubles
    ➔ Spies
    ◆ Adds instrumentation to a function/object
    ◆ Actually calls the function but gathers metadata
    ➔ Stubs
    ◆ Replaces a function for a fake implementation
    ◆ Adds instrumentation
    ◆ Returns a fixed value
    ➔ Mocks
    ◆ "Smarter" stubs
    ◆ Have predefined expectations on interactions
    ◆ Focused on the interaction, not on behaviour
    

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17. let's hack!
    

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18. TDD
    Test Driven Development
    

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20. thank you_
    lsantos.dev
    

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