This document discusses test-driven development (TDD) and behavior-driven development (BDD). It defines TDD as a process of writing tests before code to ensure requirements are met. The TDD cycle is outlined as writing a failing test, implementing code to pass the test, then refactoring. BDD is based on TDD but focuses more on validating user behaviors and scenarios. A demo is provided to illustrate TDD and BDD techniques using a wizard role-playing game example.

1. TDD / BDD
Introducing with Objective-C using XCTest
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2. Agenda
4 What is TDD?
4 TDD life-cycle
4 How to play TDD? (Demo)
4 What is BDD?
4 What is the difference between BDD and TDD?
4 How to manipulate BDD? (Demo)
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3. What is TDD?
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4. TDD means Test-Driven Development.
4 Ensure your source code.
4 Understand the feature's specification/s and
requirement/s.
4 Easily to adopt Agile for your project.
4 ...
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5. TDD is NOT about testing.
4 TDD is about Development.
4 It's all about expressing intent.
4 Specifically, improving your project.
4 Covering unit tests powerfully.
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6. TDD life-cycle
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7. 1. Write a test (Test-First)
2. Run the test (Should be FAILED)
3. Write code (Make the test pass)
4. Run all tests
5. Refactor (Clean up code)
Repeat
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8. 1. Write a test and confirm failure
2. Write code to pass all tests
3. Clean up code
Repeat
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9. For example
Just Adding Calculator
Add A to B
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10. Write a test.
- (void)testAdd3To4 {
Calc *calc = [Calc new];
XCTAssertEqualWithAccuracy(
[calc add:3 to:4], 7, .001
);
}
4 Should be failed on build because there is no
implementation.
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11. Write code
@interface Calc : NSObject
- (double)add:(double)a to:(double)b;
@end
@implementation Calc
- (double)add:(double)a to:(double)b {
return 0.;
}
@end
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12. Make the test pass
@implementation Calc
- (double)add:(double)a to:(double)b {
return 7.;
}
@end
4 Just enough code to pass.
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13. Refine the code
@implementation Calc
- (double)add:(double)a to:(double)b {
return a + b;
}
@end
4 Run all tests.
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14. Got it?
4 Memorize the figure
4 Test-First
4 Should be failed
4 Refactor, Refactor, Refactor
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15. How to play TDD?
Demo (Japanese)
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16. Wizard Role-Play
魔法使いのロールプレイ
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17. Wizard Spec (魔法使い)
4 Level 1 : 通常攻撃ができる (Attack: 1 Damage)
4 Level 3 : ギラが使える (Sizz: 2 Damage)
4 Level 5 : メラミが使える (Frizzle: 2 Damage)
4 Level up にはExp 30が一律で必要 (簡便のため)
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18. Slime Spec (スライム)
4 Life: 2, Exp: 10
Goblin Spec (ゴブリン)
4 Life: 5, Exp: 30
※モンスターは一度経験値を取得されるとExpは0となる
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19. What is BDD?
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20. BDD means Behavior-Driven Development.
4 Basically, it is based on TDD.
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21. What is the difference between
BDD and TDD?
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22. The difference between BDD and TDD?
4 TDD is focused How on code.
4 Just satisfied spec/s and requirement/s.
4 We wanna confirm a state transition.
4 A State is transitioning every-time.
4 Test-suites might have scenes on conditions.
4 BDD can check the validity of scenes.
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23. How to manipulate BDD?
Demo (Japanese)
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24. Thanks
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