『アジャイルソフトウェア開発の奥義』から学ぶテスト駆動開発

社内の勉強会で使用した資料。

Transcript

1. ʰΞδϟΠϧιϑτ΢ΣΞ։ൃͷ
   Ԟٛʱ͔ΒֶͿςετۦಈ։ൃ
   +BOVBSZUI
   5BLFTIJ:POFLVCP
   !UZPOFLVCP
   

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2. ςετϑΝʔετ
   ͱ
   ςετۦಈ։ൃ
   

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3. ςετϑΝʔετ
   ϓϩμΫτίʔυΑΓઌʹ
   ςετίʔυΛॻ͘͜ͱ
   

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4. ςετۦಈ։ൃ
   5FTU%SJWFO%FWFMPQNFOU
   ςετίʔυΛಓ۩ʹ
   

   ͯ͠ɺ։ൃΛճ͢͜ͱ
   

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5. ϨουάϦʔϯϦϑΝΫλϦϯά
   ᶃࣦഊ͢ΔςετΛॻ͘
   ᶄςετ͕௨Δγϯϓϧ
   ͳίʔυΛॻ͘
   ᶅϦϑΝΫλϦϯά͠
   ͯίʔυΛ៉ྷʹ͢Δ
   

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6. ςετϑΝʔετ͕ͩ
   ςετۦಈ։ൃͰͳ͍ྫ
   
   ઌʹ͢΂ͯͷςετίʔυΛॻ͘
   class FooTest
   {
   
   def testFoo1() {
   }
   
   def testFoo2() {
   }
   
   def testFoo3() {
   }
   
   def testFoo4() {
   }
   
   …
   
   }
   class Foo
   {
   
   // ͜Ε͔Β࣮૷
   }
   

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7. ςετϑΝʔετ͕ͩ
   ςετۦಈ։ൃͰͳ͍ྫ
   ໰୊఺
   ᶃࣦഊ͢ΔςετΛॻ͘
   ᶄςετ͕௨Δγϯϓϧ
   ͳίʔυΛॻ͘
   ᶅϦϑΝΫλϦϯά͠
   ͯίʔυΛ៉ྷʹ͢Δ
   ϑΟʔυόοΫͷܽ೗
   

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8. ςετϑΝʔετ͕ͩ
   ςετۦಈ։ൃͰͳ͍ྫ
   
   ࣄલʹઃܭ͠ա͗Δ
   class FooTest
   {
   
   def testDoFoo() {
   }
   
   }
   
   class BarTest
   {
   
   def testDoBar() {
   }
   
   }
   

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9. ςετϑΝʔετ͕ͩ
   ςετۦಈ։ൃͰͳ͍ྫ
   ໰୊఺
   ᶃࣦഊ͢ΔςετΛॻ͘
   ᶄςετ͕௨Δγϯϓϧ
   ͳίʔυΛॻ͘
   ᶅϦϑΝΫλϦϯά͠
   ͯίʔυΛ៉ྷʹ͢Δ
   ϧʔϓ͸ճΔ͕ޮՌ͕ݮΔ
   

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10. #%6'
    ࣄલͷઃܭΛ΍Γա͗Δͱ
    ޡͬͨઃܭ΍ա৒ઃܭΛੜΉ
    #JH%FTJHO6Q'SPOU
    

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11. αϯΫίετ
    ઌʹίετΛ෷ͬͯߦͬͨઃܭ͸
    ࣺͯͮΒ͍ʢଛ੾ΓͰ͖ͳ͍ʣ
    4VOL$PTU
    

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12. 2
    5%%Ͱ͸ࣄલઃܭ͸͠ͳ͍ͷʁ
    

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13. "
    ඞཁͳΒɺखॻ͖ͷϥϑεέον
    ΍$3$ͳͲखܰʹ࡞੒Ͱ͖ࣺͯͯ
    ΍͍͢πʔϧΛ࢖͏
    

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14. ʮͳΜͱͳ͘ཧղ͸Ͱ͖͚ͨͲ
    ۩ମతʹͲ͏΍ͬͯ5%%Λ
    ਐΊ͍͍͔ͯΘ͔Βͳ͍ʯ
    

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15. ͱͯ΋ྑ͍ྫ͕͋Γ·ͨ͠ʂ
    

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16. ʲୈষʳ
    ϓϩάϥϛϯά
    Τϐιʔυ
    

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17. Ϙ΢ϦϯάͷείΞूܭ
    ΞϓϦέʔγϣϯΛ5%%
    Ͱ։ൃ͢Δαϯϓϧ
    4
    5
    1 5
    14
    4
    29
    6 6
    133
    2
    49
    5
    60
    1
    61
    0
    77
    7
    97
    6
    117
    

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18. w ౤ٿॱʹ౗ͨ͠ϐϯ਺Λه࿥͢Δ
    w ࢦఆͨ͠ϑϨʔϜʹ͓͚ΔείΞΛܭࢉ
    Ͱ͖Δ
    w ࠷৽ͷείΞΛܭࢉͰ͖Δʢશͯͷ౤ٿ
    ͕׬͍ྃͯ͠Ε͹ɺ࠷ऴతͳείΞʣ
    4
    5
    1 5
    14
    4
    29
    6 6
    133
    2
    49
    5
    60
    1
    61
    0
    77
    7
    97
    6
    117
    ৼΔ෣͍ʢΞϓϦέʔγϣϯ࢓༷ʣ
    

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19. ࣄલઃܭʢϥϑεέονʣ
    

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20. Ϙϒ͓͡͞Μͱಉ྅͕
    ϖΞϓϩͰḷͬͨಓے
    

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21. w ςετ͢΂͖5ISPXͷৼ෣͍͕ݟ͍ͩͤͣɺ
    'SBNFͷςετ͔Βॻ͖࢝Ίͨɻ
    w ࠷΋୯७ͳςετέʔε͔Β࢝Ίɺ࠷΋୯७ͳ
    ࣮૷ͰςετΛ௨͢ɻ
    ࠷ॳͷςετέʔε
    public class Frame
    {
    
    public int getScore()
    {
    
    return 0
    ;
    
    }
    
    }
    
    class FrameSpec extends Specification
    {
    
    def "ະ౤ٿͷͱ͖ͷείΞ͸0Ͱ͋Δ"()
    {
    
    given
    :
    
    def f = new Frame(
    )
    
    when
    :
    
    def score = f.getScore(
    )
    
    then
    :
    
    score ==
    0
    
    }
    
    }
    
    ˞ॻ੶Ͱ͸+6OJUΛ࢖͍ͬͯΔ
    ͕ɺຊࢿྉͰ͸4QPDLΛ࢖༻
    

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22. w ࣍ʹ୯७ͳςετέʔεΛ௥Ճ͠ɺςετ͕௨
    ΔΑ͏ʹίʔυΛमਖ਼͢Δ
    ࣍ͷςετέʔε
    class FrameSpec extends Specification
    {
    
    ..
    def "1ճ౤ٿͨ͠ͱ͖ʹείΞ͕ਖ਼͍͠"()
    {
    
    given
    :
    
    def f = new Frame(
    )
    
    when
    :
    
    f.add(5
    )
    
    then
    :
    
    f.getScore() ==
    5
    
    }
    
    }
    
    public class Frame
    {
    
    private int itsScore = 0
    ;
    
    public int getScore()
    {
    
    return itsScore
    ;
    
    }
    
    public void add(int pins)
    {
    
    itsScore += pins
    ;
    
    }
    
    }
    
    

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23. ग़ͩ͠͸ॱௐʂ
    

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24. w εϖΞ΍ετϥΠΫΛग़ͨ͠৔߹ɺϑϨʔϜͷ
    είΞܭࢉʹ͸ޙଓͷϑϨʔϜͷ৘ใ͕ඞཁɻ
    w (BNFΦϒδΣΫτ͸'SBNFΛϦϯΫϦετͰ
    ؅ཧ͢΂͖ʁ
    w 'SBNFͷ࡞ۀΛதஅͯ͠ɺ(BNFͷ࡞ۀʹ੾Γ
    ସ͑Δɻ
    ෳ਺ճ౤ٿͨ͠৔߹ʁ
    

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25. (BNFͷ࣮૷Λগͣͭ͠ਐΊΔ
    class GameSpec extends Specification
    {
    
    when
    :
    
    g.add(5
    )
    
    g.add(4
    )
    
    g.add(7
    )
    
    g.add(2
    )
    
    then
    :
    
    g.score() == 1
    8
    
    g.scoreForFrame(1) ==
    9
    
    g.scoreForFrame(2) == 1
    8
    
    }
    
    public class Game
    {
    
    private int itsScore = 0
    ;
    
    private int[] itsThrows = new int[21]
    ;
    
    private int itsCurrentThrow = 0
    ;
    
    public int score()
    {
    
    return itsScore
    ;
    
    }
    
    public void add(int pins)
    {
    
    itsThrows[itsCurrentThrow++] = pins
    ;
    
    itsScore += pins
    ;
    
    }
    
    public int scoreForFrame(int frame)
    {
    
    int score = 0
    ;
    
    for (int ball = 0; frame > 0 && (ball < itsCurrentThrow)
    ;
    
    ball += 2, frame--)
    {
    
    score += itsThrows[ball] + itsThrows[ball + 1]
    ;
    
    }
    
    return score
    ;
    
    }
    
    }
    
    

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26. lίʔυ͕ͦΕΛඞཁͩͱ
    ओு͠ͳ͍ݶΓɺϦϯΫϦετ͸
    ༻ҙͨ͘͠ͳ͍Μͩz
    

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27. w ୯ͳΔ഑ྻͰ༻Λ଍͢ͳΒɺͦΕͰ0,
    w ઃܭ্ͷ൑அΛ஗ΒͤΔ
    γϯϓϧͳઃܭΛબ୒͠Α͏
    public class Game
    {
    
    private int itsScore = 0
    ;
    
    private int[] itsThrows = new int[21]
    ;
    
    private int itsCurrentThrow = 0
    ;
    
    

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28. w ςετ͕͋Δ͔Β҆৺ϦϑΝΫλϦϯά
    ৗʹϦϑΝΫλϦϯά͠Α͏
    public int scoreForFrame(int frame)
    {
    
    int score = 0
    ;
    
    for (int ball = 0; frame > 0 && (ball < itsCurrentThrow)
    ;
    
    ball += 2, frame--)
    {
    
    score += itsThrows[ball] + itsThrows[ball + 1]
    ;
    
    }
    
    return score
    ;
    
    }
    public int scoreForFrame(int theFrame)
    {
    
    int ball = 0
    ;
    
    int score = 0
    ;
    
    for (int currentFrame = 0; currentFrame < theFrame
    ;
    
    currentFrame++)
    {
    
    int firstThrow = itsThrows[ball++]
    ;
    
    int secondThrow = itsThrows[ball++]
    ;
    
    score += firstThrow + secondThrow
    ;
    
    }
    
    return score
    ;
    
    }
    

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29. w εϖΞΛग़ͨ͠ͱ͖
    w ετϥΠΫΛग़ͨ͠ͱ͖
    w ύʔϑΣΫτήʔϜ
    w ϦΞϧͳαϯϓϧ
    w ΤοδέʔεʢύʔϑΣΫτήʔϜະ਱ͳͲʣ
    ઴ਐతʹ(BNFͷ࣮૷ΛਐΊΔ
    4
    5
    1 5
    14
    4
    29
    6 6
    133
    2
    49
    5
    60
    1
    61
    0
    77
    7
    97
    6
    117
    

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30. w શͯͷςετέʔε͕௨ΓɺΞϓϦέʔγϣϯ
    ͷৼΔ෣͍͕׬੒͕ͨ͠ɺϦϑΝΫλϦϯά͸
    ଓ͍͍ͯ͘ɻ
    w 4DPSFSΦϒδΣΫτͷඞཁੑΛ೏Θͤͳ͕
    Βɺͪ͝Ό͍ͭͨίʔυΛ͖Ε͍ʹ͍ͯ͘͠ɻ
    ͞ΒͳΔϦϑΝΫλϦϯά
    

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31. if (strike())
    {
    
    score += 10 + nextTwoBallsForStrike()
    ;
    
    ball++
    ;
    
    } else if (spare())
    {
    
    score += 10 + nextBallForSpare()
    ;
    
    ball+=2
    ;
    
    } else
    {
    
    score += handleSecondThrow()
    ;
    
    }
    l͜ͷTDPSF'PS'SBNFؔ਺Λݟͯ͝ΒΜΑʂ
    ͜Εͦ͜Ϙ΢ϦϯάͷϧʔϧΛ͖ΘΊͯ؆ܿ
    ʹهड़ͨ࢟ͩ͠Αʂz
    

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32. ׬੒ܗ
    l͜ΕͰɺ(BNF͸ϑϨʔϜͷ؅ཧ͚ͩΛͯ͠ɺ
    4DPSFS͸είΞͷܭࢉ͚ͩΛ୲౰͢Δਤࣜʹͳͬ
    ͨͶɻ͜Εͧɺ୯Ұ੹೚ͷݪଇʢ431ʣͩʂz
    

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33. ͲͪΒͷઃܭ͕͙͢Ε͍ͯΔ͔ʁ
    if (strike())
    {
    
    score += 10 + nextTwoBallsForStrike()
    ;
    
    ball++
    ;
    
    } else if (spare())
    {
    
    score += 10 + nextBallForSpare()
    ;
    
    ball+=2
    ;
    
    } else
    {
    
    score += handleSecondThrow()
    ;
    
    }
    ࣄલͷઃܭ 5%%ʹΑΔઃܭ
    

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34. ద੾ͳϞσϦϯά
    ࣮ੈքͷ֓೦ߏ଄Λ஧࣮ʹղܾྖ
    Ҭʹ࠶ݱ͢Δ͜ͱ͕͍ͭ΋ਖ਼͍͠
    ͱ͸ݶΒͳ͍
    

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35. ٙ໰
    4DPSFS͸ςετ͠ͳ͍ͷʁ
    

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36. ϢχοτςετͷʮϢχοτʯ
    lϢχοτͱ͸;Δ·͍ͷ୯
    Ґɺͭ·Γಠཱͨ͠ݕূՄ
    ೳͳ;Δ·͍ͷ͜ͱͩz
    

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37. ৼ෣͍ͷू߹ମΛςετ͢Δ
    l͋ΒΏΔ؍࡯Մೳͳ;Δ·
    ͍͕ɺͦΕʹඥͮ͘ςετ
    Λ࣋ͭ΂͖Ͱ͋Δ͜ͱΛҙ
    ຯ͢Δɻz
    

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38. ৼΔ෣͍ͷू߹ମͷϑΝαʔυͰ
    ͋Δ(BNFΛςετ͢Ε͹0,
    

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39. ࣮ࡍɺΧόϨοδ΋໰୊ͳ͔ͬͨ
    

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40. w 5%%ͷαΠΫϧͰ(BNFͷৼ෣͍Λશ࣮ͯ૷͠
    ͨޙɺϦϑΝΫλϦϯάͰ4DPSFSΛநग़ɻ
    w (BNF4QFDͰৼ෣͍Λݻఆ͢Δ͜ͱͰɺϦ
    ϑΝΫλϦϯάΛߦ͏͜ͱ͕Ͱ͖ͨɻ
    Ϙϒ͓͡͞Μୡ͕ḷͬͨ࿏
    

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41. w ॻ੶ͷதͰϘϒ͓͡͞Μୡ͕ḷͬͨ࿏ΛɺԾʹ
    ηΠόʔϧʔτͱݺͿʢ࣭໰͸ड͚෇͚ͳ͍ʣ
    5%%ͷϧʔτ͸Ұͭͱ͸ݶΒͳ͍
    

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42. w 4DPSFSͷඞཁੑ͕ݟ͑ͨஈ֊Ͱ4DPSFS4QFD
    Λ࡞੒͠ɺ5%%Ͱ4DPSFSΛઌʹ࢓্͛Δɻ
    w ΠϯαΠυΞ΢τʢϘτϜΞοϓʣɻ
    ႒ϧʔτ
    

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43. w 4DPSFSͷඞཁੑ͕ݟ͑ͨΒɺ4DPSFSͷϞοΫ
    Λ࢖ͬͯ(BNFͷ࣮૷ΛਐΊ͍ͯ͘ɻ
    w Ξ΢ταΠυΠϯʢτοϓμ΢ϯʣɻ
    ࡩϧʔτ
    

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44. ϞοΫΛ࢖ͬͨςετ
    private Game
    g
    
    private Scorer
    s
    
    def setup()
    {
    
    s = Mock() // ScorerͷϞοΫ
    g = new Game(s
    )
    
    }
    
    def "2ճ౤ٿͨ͠ͱ͖ͷείΞ͕ਖ਼͍͠"()
    {
    
    when
    :
    
    g.add(5
    )
    
    g.add(4
    )
    
    def score = g.score(
    )
    
    then
    :
    
    score ==
    9
    
    1 * s.addThrow(5
    )
    
    1 * s.addThrow(4
    )
    
    1 * s.scoreForFrame(2) >>
    9
    
    }
    
    ؒ઀ೖྗ
    ؒ઀ग़ྗ
    ʨ
    ૬ޓ࡞༻ͷݕূ
    

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45. w (BNFΛपΓ͔Βಠཱͯ͠ςετͰ͖Δɻ
    w 4DPSFSͷ࣮૷͕ͳ͍࣌఺Ͱɺઌʹ(BNFΛςε
    τͰ͖Δɻ
    w ϞοΫΛܦ༝͠ɺؒ઀ೖྗ΍ؒ઀ग़ྗΛ࢖ͬͯ
    (BNFͷৼ෣͍΍ঢ়ଶΛνΣοΫͰ͖Δɻ
    w (BNFͱ4DPSFSͷ૬ޓ࡞༻ΛδϟετΠϯλΠ
    ϜͰઃܭͰ͖Δɻ
    ϞοΫΞϓϩʔνͷϝϦοτ
    

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46. w ࣮૷ͷৄࡉʹґଘ͢ΔͨΊɺ੬͍ςετͱͳΓ
    ΍͍͢ɻ
    w ॻ͘ͷʹख͕͔͔ؒΔɻ
    w (BNF4DPSFSʢৼ෣͍ͷू߹ମʣʹର͢Δ
    ςετ΋ผ్ॻ͘ඞཁ͕͋Δɻ
    ϞοΫΞϓϩʔνͷσϝϦοτ
    

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47. w ϞοΫΛ࢖ͬͯॻ͍ͨ(BNF4QFD͸͋͘·Ͱ
    ઃܭΛਐΊΔҰ࣌తͳಓ۩ͱߟ͑ɺࣺͯͯΑ͠
    ʢৼ෣͍ͷू߹ମʹର͢Δςετ͕࢒Ε͹Մʣ
    ઃܭͷͨΊ͚ͩͷςετίʔυ
    

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48. ·ͱΊ
    

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49. 5%%ͷຊ࣭͸ɺ
    ϨουάϦʔϯϦϑΝΫλϦϯά
    ͷαΠΫϧͰߦ͏
    δϟετΠϯλΠϜͷઃܭͰ͋Δ
    

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50. Ϣχοτςετͷ୯Ґ͸
    ৼ෣͍ͷू߹ମͱ͠Α͏
    

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51. ʰΞδϟΠϧιϑτ΢ΣΞ։ൃͷ
    ԞٛʱষΛࣸܦͯ͠Έ·͠ΐ͏
    

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52. ʰΞδϟΠϧιϑτ΢ΣΞ։ൃͷԞٛୈ̎൛ʱ
    ϩόʔτɾ$ɾϚʔνϯஶ4#ΫϦΤΠςΟϒץ
    
    ʰϨΨγʔίʔυ͔Βͷ୤٫ʱ
    %BWJE4DPUU#FSOTUFJOஶΦϥΠϦʔɾδϟύϯץ
    
    ࢀߟจݙ
    

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