TDD / BDDIntroducing with Objective-C using XCTest

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Agenda4 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)© kaneshin, 2014 2

What is TDD?

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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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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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TDD life-cycle

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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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1. Write a test and confirm failure

2. Write code to pass all tests

3. Clean up code

Repeat

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For exampleJust Adding Calculator

Add A to B

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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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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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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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Refine the code

@implementation Calc- (double)add:(double)a to:(double)b { return a + b;}@end

4 Run all tests.

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Got it?

4 Memorize the figure

4 Test-First

4 Should be failed

4 Refactor, Refactor, Refactor

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How to play TDD?Demo (Japanese)

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Wizard Role-Play魔法使いのロールプレイ

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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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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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What is BDD?

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BDD means Behavior-Driven Development.

4 Basically, it is based on TDD.

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What is the difference between BDD and TDD?

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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.© kaneshin, 2014 22

How to manipulate BDD?Demo (Japanese)

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Thanks

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