In this presentation I give a practice example of how unit testing your view controllers in Swift can create coupling between your test and implementation - and then proceed to de-couple these components through a live-coding exercise and make the test easier to understand through refactoring. These slides are the introduction to the presentation and were followed by a live-coding session. GitHub Repo: https://github.com/derekleerock/UIButtonDecouple/tree/master

1. Decoupling,
Decluttering
and Demystifying
Your Swift Tests
Tokyo iOS Meetup Nov 2017
derek lee
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2. Why Testing?
Why TDD?
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3. Our Desired Outcome:
We want to "Go Fast Forever"
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4. We want to "Go Fast Forever"
In order to do that, we need:
Clean Code + SOLID/OO Design
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5. We want to "Go Fast Forever"
Clean Code + SOLID/OO Design
The process that helps us get to clean code is:
Refactoring
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6. We want to "Go Fast Forever"
Clean Code + SOLID/OO Design
Refactoring
This gives us:
Confidence
in working software for our users
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7. We want to "Go Fast Forever"
Clean Code + SOLID/OO Design
Refactoring
Confidence
To be able to refactor with confidence, we:
Write Tests
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8. We want to "Go Fast Forever"
Clean Code + SOLID/OO Design
Refactoring
Confidence
And if everything depends on tests...
Write Tests → TDD
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9. We want to "Go Fast Forever"
Clean Code + SOLID/OO Design
Refactoring
Confidence
TDD
"TDD: The Bad Parts"
https://youtu.be/xPL84vvLwXA
Matt Parker, Pivotal Labs Head of Engineering
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10. Why do we write unit tests?
• Act of Design
• Executable Documentation
• Verification (now, and later)
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11. Today's Goal
• De-couple your tests from the implementation details
• Make your tests more readable, comparable to
documentation
• Write easier to understand and more succinct tests
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12. LIVE CODING DEMO
!
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13. What did we cover today?
• Red/Green/Refactor; 3 Laws of TDD; Arrange/Act/Assert
• Refactoring for clarity / readability
• How to easily fold "helper" functions into extensions
• How to write tests that are de-coupled from the impl.
• Example of Dependency Injection using a Spy Test Double
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14. Today's Project on GitHub:
↓
https://github.com/
derekleerock/UIButtonDecouple
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15. Thank You!
@derekleerock
github.com/derekleerock
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