Clean Test Code Revised

Rails Developer Meetup 2019での発表資料です！可読性の高いテストコードを書くためのコツについて話しました

Transcript

1. Clean Test Code
   Revised
   @willnet
   

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2. Έͳ͞Μ
   ςετॻ͍ͯ·͔͢ʁ
   

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3. ͜͜Ͱશһख্͕͕
   Δ༧ఆ✋
   
   

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4. ςετॻ͘ͷָ͍͠
   ਓʁ
   

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5. ͜͜Ͱશһ͕໨Λ෬
   ͤΔ༧ఆ
   
   

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6. Ͳ͏͍͏ͱ͖ʹͭΒ͍ʁ
   w ͨ·ʹ$*͚ͩͰίέΔςετ
   w ͳʹΛͲ͏ςετͯ͠Δͷ͔Θ͔Βͳ͍ςετίʔυͷղ
   ಡ
   w ςετͷఆٛΛҰͭมߋͨ͠Βେྔͷ
   

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7. Ͳ͏͍͏ͱ͖ʹͭΒ͍ʁ
   w ͨ·ʹ$*͚ͩͰίέΔςετ
   w ͳʹΛͲ͏ςετͯ͠Δͷ͔Θ͔Βͳ͍ςετίʔυͷղ
   ಡ
   w ςετͷఆٛΛҰͭมߋͨ͠Βେྔͷ
   طଘͷςετίʔυ
   मਖ਼͕ͭΒ͍
   

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8. Ͳ͏͍͏ͱ͖ʹͭΒ͍ʁ
   w ͨ·ʹ$*͚ͩͰίέΔςετ
   w ͳʹΛͲ͏ςετͯ͠Δͷ͔Θ͔Βͳ͍ςετίʔυ
   w ఆٛΛҰͭมߋͨ͠Βେྔͷ
   A
   ࠓ೔࿩͢͜ͱ
   

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9. Մಡੑͷߴ͍ίʔυΛ
   मਖ਼͢ΔͳΒਏ͘ͳ͍͸ͣʜ
   

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10. 8F`SFOPUIJSJOH
    ҎલɺՄಡੑͷߴ͍
    ςετίʔυͷॻ͖ํ
    ʹ͍ͭͯ࿩͠·ͨ͠
    https://speakerdeck.com/willnet/clean-test-code
    

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11. 3BJMT%FWFMPQFST
    .FFUVQ
    ӫ͑͋ΔୈҰճ໨ʂ
    

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12. ൃද͔Β೥ܦͪ
    ಄͕੔ཧ͞Ε͖ͯͨͷͰ΋ͬ
    ͱ͍͍ײ͡ͷઆ໌͕Ͱ͖ͦ͏
    

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13. ͔͜͜Βຊ୊
    

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14. ࠓ೔͸$MFBO5FTU
    $PEF Մಡੑͷߴ͍ς
    ετίʔυ
    ʹ͍ͭͯ
    ࿩͠·͢
    

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15. Ͳ͏͍͏ঢ়ଶͩͱ
    ʮՄಡੑͷߴ͍ςετ
    ίʔυʯͱݴ͑Δͷ͔
    
    

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16. ཧ૝ͷ͕࢟Θ͔Βͳ͍
    ͱमਖ਼͠Α͏͕ͳ͍ʜ
    

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17. ೴ʹෛ୲Λ͔͚ͳ͍
    ςετίʔυ͸Մಡੑ
    ͕ߴ͍
    

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18. ๻ͨͪ͸ςετίʔυ
    ΛಡΉͱ͖ɺςετͷ
    ಺༰Λ೴಺ϝϞϦʹల
    ։͍ͯ͠Δ
    

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19. ೴಺ϝϞϦʹల։͍ͯ͠Δ
    ཁૉ
    w ςετͷ֓ཁ
    w ςετͷࣄલ৚݅
    w खଓ͖
    w ظ଴͍ͯ͠Δ݁Ռ
    

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20. αϯϓϧίʔυ
    

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21. ֓ཁ
    6TFSGVMMOBNF͕੏ͱ໊Λ͋Θͤͨ΋ͷΛ
    ฦ͢͜ͱΛςετ͍ͯ͠Δ
    

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22. લఏ৚݅
    pSTUOBNF͕`ਅҰ` MBTUOBNF͕`લౡ`ͷ
    6TFSΦϒδΣΫτΛੜ੒͠ɺVTFSͰࢀরͰ͖ΔΑ͏ʹ͍ͯ͠Δ
    

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23. खଓ͖
    VTFSGVMMOBNFΛ࣮ߦ͢Δ
    

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24. ظ଴͢Δ݁Ռ
    bલౡਅҰ`͕໭Γ஋ͱͯ͠ฦΔ
    

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25. ςετίʔυ͔Β
    ΁ͷϚοϐϯά
    

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26. ͜ΕΒΛ͢ΜͳΓల։͞
    ͤͳ͍ཁૉ͕ଘࡏ͢Δ
    

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27. ೴ʹෛ୲Λ͔͚Δཁૉ
    Λഉআͨ͠ςετίʔ
    υ͸Մಡੑ͕ߴ͍
    

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28. ೴ʹෛ୲Λ͔͚Δཁૉ
    ͱ͸
    

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29. ೴ʹෛ୲Λ͔͚Δཁૉ
    w આ໌ෆ଍
    w είʔϓʹϊΠζ͕͍ࠞͬͯ͟Δ
    w είʔϓͷඈͼ஍
    w ҉໧తͳґଘ͕͋Δ
    w ఆٛΛ్தͰมߋ͢Δ
    

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30. આ໌ෆ଍
    

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31. આ໌ෆ଍
    w EFTDSJCF DPOUFYU JUͷઆ໌͕ࡶɺ΋͘͠͸આ໌͕ͳ͍
    w ςετͷ֓ཁ͕͙͢ʹ͔ͭΊͣɺ೴ͷϦιʔεΛফඅ͢Δ
    

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32. View Slide

33. EFTDSJCF΍DPOUFYU͕୯ޠ͚ͩ
    JUͷઆ໌͕লུ
    ͳʹΛͲ͏ςετ͍ͯ͠Δͷ͔͙͢ʹ͸Θ͔Βͳ͍
    

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34. View Slide

35. จষΛಡΉ͚ͩͰ
    ֓ཁ͕͙͢ʹΘ͔Δʂ
    

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36. ཧ૝͸EFTDSJCF
    DPOUFYU JUΛಡΊ͹ςε
    τͷྲྀΕΛཧղͰ͖Δ͜ͱ
    

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37. ݱ৔ͷςετίʔυͰ͸
    JUͷઆ໌͕লུ͞Ε͕ͪ
    

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38. ॻ͍ͨຊਓʹͱͬͯ͸ࣗ
    ໌͔΋͠Εͳ͍͚Ͳɺ
    ޙੈͷਓ͕ͭΒ͍ͷͰ
    ৄ͘͠ॻ͖·͠ΐ͏
    

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39. JUͷઆ໌Λলུͯ͠Α͍ͷ͸ɺϫϯϥΠφʔܗ
    ࣜͰ͔ͭTVCKFDUͱϚονϟ͕୯७ͳ΋ͷ͚ͩ
    

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40. ·ͱΊ
    ςετ͸આ໌͗͢͠
    ͘Β͍Ͱͪΐ͏ͲΑ͍
    

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41. είʔϓʹϊΠζ͕ࠞ
    ͍ͬͯ͟Δ
    

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42. ͜͜Ͱ͍͏είʔϓͱ͸
    ֘౰͢Δςετʹؔ܎͢Δ
    ϒϩοΫͷ͜ͱͰ͢
    

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43. ͷείʔϓ
    

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44. ͷείʔϓ
    

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45. ྫCͱDͰ͚ͩ࢖͏
    ఆ͕ٛ͋Δ
    

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46. %3:ʹ͢ΔͨΊʹ
    Ұ্ͭʹҠಈ
    

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47. %3:ʹ͢ΔͨΊʹ
    Ұ্ͭʹҠಈ
    (
    

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48. %3:ʹ͢ΔͨΊʹ
    Ұ্ͭʹҠಈ
    ͜ͷఆٛ͸ࠓݟ͍ͯΔε
    ίʔϓͰ࢖ΘΕ͍ͯΔͷ
    ͔ʁ࢖ΘΕ͍ͯͳ͍ͷ
    ͔ʁͱ͍͏൑அ͕ඞཁʹ
    ͳΓ೴ͷϦιʔεΛফඅ
    ͢Δ
    

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49. MFUΛMFUʹ͢Δͱ஗ԆධՁͰ`B`ͷίϯς
    ΩετͰ͸࣮ߦ͞Εͳ͍͔ΒΑ͍ͷͰ͸ʁ
    

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50. MFUΛMFUʹ͢Δͱ஗ԆධՁͰ`B`ͷίϯς
    ΩετͰ͸࣮ߦ͞Εͳ͍͔ΒΑ͍ͷͰ͸ʁ
    (
    

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51. MFUΛMFUʹ͢Δͱ஗ԆධՁͰ`B`ͷίϯς
    ΩετͰ͸࣮ߦ͞Εͳ͍͔ΒΑ͍ͷͰ͸ʁ
    MFUͷ஗Ԇ࣮ߦʹΑͬͯϚ
    γϯ্Ͱ࣮ߦ͞Εͳͯ͘
    ΋೴ͷϝϞϦ͸ফඅ͞Ε
    Δ
    

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52. MFUͱMFUͲͪΒͰ΋
    ྑ͍৔߹͸MFU
    

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53. ·ͱΊ
    είʔϓʹ͸࢖͏΋ͷ
    ͚ͩΛఆٛ͢Δ
    

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54. είʔϓͷඈͼ஍
    

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55. View Slide

56. ΤσΟλΛεΫϩʔϧ
    ͍ͯ͠Δؒʹ೴಺ϝϞ
    Ϧ͕شൃ͕ͪ͠
    

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57. ͜ͷྫ͸͏·͍
    ղܾࡦ͕ͳ͍ʼʻ
    ͋Μ·ΓͭΒ͍Α͏ͳΒ
    ωετΛ΍ΊΔͷ͕Αͦ͞͏
    

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59. ผϑΝΠϧͷఆٛΛߦͬͨΓ
    དྷͨΓ͍ͯ͠Δؒʹ೴಺ϝϞ
    Ϧ͕شൃ͕ͪ͠
    

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60. ϑΝΠϧதͰ͔͠࢖͍ͬͯͳ͍
    ϔϧύϝιουͳΒ͜͏͍ͨ͠
    

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61. ·ͱΊ
    είʔϓͷඈͼ஍ΛͰ͖Δݶ
    ΓݮΒ͢ɻ΍ΉΛಘͳ͍ͱ͖
    ΋ͳΔ΂ۙ͘͘ʹ഑ஔ͢Δ
    

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62. ҉໧తͳґଘ
    

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63. TUBUVT͸SFBEZEPJOHEPOFͷҰํ޲͔͠ભҠͰ͖ͳ͍
    ͦΕҎ֎ͷભҠΛ͠Α͏ͱͨ͠ΒΤϥʔͱ͍͏࢓༷
    

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65. TUBUVTͷσϑΥϧτ͕SFBEZͰ͋Δ͜ͱʹґଘ͍ͯ͠Δ͕ɺ
    ςετίʔυ୯ମΛΈ͚ͨͩͰ͸ؾ͚ͮͳ͍
    

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66. TUBUVTͷσϑΥϧτ͕SFBEZͰ͋Δ͜ͱʹґଘ͍ͯ͠Δ͕ɺ
    ςετίʔυ୯ମΛΈ͚ͨͩͰ͸ؾ͚ͮͳ͍
    ΋ͪΖΜςετέʔε͕଍Γͳ͍
    ͱ͍͏ͷ΋͋Δ͚ͲͦΕ͸ஔ͍͓͍͍ͯͯͩ͘͞
    
    

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67. ςετίʔυதʹॻ͔Ε
    ͍ͯͳ͍҉໧తͳ৚݅
    FYGBDUPSZ@CPUͷσ
    ϑΥϧτ஋
    ʹґଘͨ͠
    ίʔυΛॻ͘ͱɺࣄલ৚
    ݅ͷ೺Ѳ͕೉͘͠ͳΔ
    

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68. ࣄલ৚݅Λਖ਼͘͠೺ѲͰ͖
    ͳ͍ঢ়ଶͰςετίʔυΛ
    ॻ͘ͱɺಡΈͮΒ͍ෆ҆ఆ
    ͳςετίʔυʹͳΔ
    

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69. ΋ͪΖΜσϑΥϧτ஋Λ
    มߋͨ͠Βͱ͍͏ͷ΋͋Δ
    

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70. ඞཁͷͳ͍ϊΠζ
    

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71. ͋Δ΂͖࢟
    

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72. ͖ͬ͞΋ݴ͚ͬͨͲ
    େࣄͳ͜ͱͳͷͰ
    ΋͏Ұ౓
    

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73. ςετʹؔ܎͍ͯ͠Δ
    ஋Λɺςετίʔυ֎
    ʹॻ͘ͱͭΒ͍
    

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74. ͭΒ͍
    

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75. ςετʹؔ܎͍ͯ͠Δ
    ஋Λɺςετίʔυ্
    Ͱաෆ଍ͳ͘໌ࣔతʹ
    ࢦఆ͢ΔͱಡΈ΍͍͢
    

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76. ͜ͷதʹ͢΂ͯΛॻ͍͍ͯͩ͘͞ʂ
    

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77. ͱ͸͍͑ɺ
    'BDUPSZ#PUͷσϑΥ
    ϧτ஋ʹґଘͨ͠ίʔ
    υ͸ॻ͍ͯ͠·͍͕ͪ
    

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78. ਪ঑ϓϥΫςΟε
    ʮσϑΥϧτ஋Λϥϯ
    μϜʹ͢Δʯ
    

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79. ඞཁͳ஋ͷઃఆʹෆ଍͕͋Δͱ
    ͱ͖Ͳ͖ςετ͕ίέΔΑ͏ʹͳΔ
    

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80. 2ϥϯμϜʹ͢Δͱ
    ςετ͕ίέͨͱ͖ʹ
    ࠶ݱͰ͖ͳ͘ͳ͍ʁ
    

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81. "ςετ͕ίέͨͱ͖
    ͸ASTQFDŠTFFE
    AͷΑ͏ʹTFFE
    ஋Λࢦఆ͢Δͱ࠶ݱͰ
    ͖Δ
    

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82. ·ͱΊ
    ςετʹؔ࿈͍ͯ͠Δ஋
    ΛͳΔ΂͘ςετίʔυ
    ಺ʹدͤͯදݱ͢Δɻա
    ෆ଍͕ͳ͍Α͏ʹ͢Δ
    

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83. ఆٛΛ్தͰมߋ͢Δ
    

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84. View Slide

85. ҉໧ͷґଘ
    

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86. ͜Εʹґଘͨ͠ςετίʔυ͕͢Ͱʹଘࡏ͢Δͱ
    ͜ͷఆٛΛมߋ͠ʹ͘͘ͳΔ
    

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87. ґଘΛͦͷ··࢖ͬͯ
    ແཧ΍ΓςετΛॻ͍ͨྫ
    

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88. σϑΥϧτ஋͕໌ࣔతͰͳ͍
    ͷͰɺGBDUPSZͷϑΝΠϧͱ
    ςετͷϑΝΠϧΛߦͬͨΓདྷͨΓ
    ͢Δඞཁ͕͋Δ
    

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89. ಈతʹσϑΥϧτ஋Λ
    ม͑Δͱ࠷ऴతͳ஋͕
    ෼͔ΓͮΒ͘ͳΔ
    

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90. USBJUΛ࢖͍ɺσϑΥϧτͰ͸
    QPTU͕࡞ΒΕͳ͍Α͏ʹมߋ
    

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91. ґଘ͍ͯ͠Δ΋ͷΛ໌ࣔతʹͯ͠
    ςετίʔυຊମʹॻ͘͜ͱ͕Ͱ͖ͨ
    

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92. ྫΛ΋͏গ͠
    

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94. ֎ଆͷείʔϓͰఆٛͨ͠QPTUΛVQEBUF͍ͯ͠ΔͷͰɺ
    ೴಺NFSHF͕ඞཁ
    

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95. ͦΕͧΕͷείʔϓͰ໌ࣔతʹQPTUΛఆٛͨ͠΄͏͕
    Θ͔Γ΍͍͢
    

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97. ֎ଆͷMFUͰఆٛͨ͠QVCMJTI@BUΛ্ॻ͖ͨ͠Γ
    ͍ͯ͠ͳ͔ͬͨΓ͢ΔͷͰɺ೴಺ϑΟϧλϦϯά͕ඞཁ
    

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98. σϑΥϧτͷMFUΛ΍Ίͯ
    ͦΕͧΕͷDPOUFYUͰ໌ࣔతʹఆٛ͢Δͱ
    ೴಺ϑΟϧλϦϯά͕ෆཁʹͳΔ
    

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99. ֎ଆͷείʔϓͰఆٛ
    ͨ͠΋ͷΛ಺ଆͷε
    ίʔϓͰߋ৽͢Δͱ೴
    ʹෛ୲͕͔͔Δ
    

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100. ·ͱΊ
     ςετͷલఏ৚݅Λ্
     ॻ͖ͨ͠Γमਖ਼ͨ͠Γ
     ͠ͳ͍
     

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101. ೴ʹෛ୲Λ͔͚Δཁૉ
     ʹ͍ͭͯҰ௨Γ࿩ͨ͠
     

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102. ೴ʹෛ୲Λ͔͚Δཁૉ ࠶ܝ
     
     w આ໌ෆ଍
     w είʔϓʹϊΠζ͕͍ࠞͬͯ͟Δ
     w είʔϓͷඈͼ஍
     w ҉໧తͳґଘ͕͋Δ
     w ఆٛΛ్தͰมߋ͢Δ
     

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103. ೴ʹෛ୲Λ͔͚Δཁૉ
     Λෳ਺ؚΈ͕ͪͳ΋ͷ
     ͕͋Δ
     

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104. ͦΕ͸ʜ
     

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105. TIBSFE@DPOUFYU
     TIBSFE@FYBNQMFT
     

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106. ͜ΕͰۤ͠ΜͩPS
     ۤ͠ΜͰ͍Δਓ✋
     

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107. %3:ʹ͍ͨ͠ཉٻ͕
     TIBSFE଒Λঌש͢Δ
     

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108. TIBSFE଒Λ࢖͏ͳ
     Βɺ͜Ε·Ͱ࿩ͨ͠ϓ
     ϥΫςΟεΛͰ͖Δ͔
     ͗Γ੝ΓࠐΈ·͠ΐ͏
     

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110. આ໌͕଍Γͳ͍
     

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111. Ṗͷґଘؔ܎
     

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112. TIBSFE@FYBNQMFTͷఆٛͱ
     ςετίʔυΛߦͬͨΓདྷͨ
     Γͯ͠ɺ೴಺Ͱ
     ʮTIBSFE@FYBNQMFTΛ࢖Θ
     ͳ͔ͬͨͱ͖ͷίʔυʯʹม
     ׵͠ͳ͍ͱͳʹ΋Θ͔Βͳ͍
     

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113. मਖ਼Ҋ
     

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114. આ໌Λৄͯ͘͠͠
     ςετίʔυ಺͚ͩͰ֓ཁΛ͔ͭΊΔΑ͏ʹͨ͠
     

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115. ͔͠͠Ҿ਺ʹظ଴͢Δ݁ՌΛ౉ͯ͠ಈతʹJUͷ಺༰Λมߋ͢Δ
     ͱ͍͏͜ͱࣗମ͕ՄಡੑΛଛͶ͍ͯΔ
     ݁ہఆٛΛಡΜͰ೴಺Ϛʔδͷඞཁ͕͋Δ
     
     

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116. ΂ͨॻ͖ʹͯ͠Έͨ
     

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117. ݟ΍͘͢ͳ͕ͬͨ
     ιʔείʔυߦ਺͸૿͑ͨ
     

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118. όϥϯεΛ
     ߟ͑·͠ΐ͏
     

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119. Լखʹ෼͚Δ͘Β͍ͳ
     ΒίϐϖͰ΂ͨॻ͖ͷ
     ΄͏͕ίετ௿͍Ͱ͢
     

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120. શମͷ·ͱΊ
     w Մಡੑͷߴ͍ςετͷॻ͖ํʹ͍ͭͯઆ໌͠·ͨ͠
     w ςετίʔυ͸ΞϓϦέʔγϣϯίʔυͱͪΐͬͱ͚͓ͩ
     ࡞๏͕ҧ͏
     w ΞϓϦέʔγϣϯίʔυ΄ͲՄಡੑ͕ߟྀ͞Ε͍ͯͳ͍ง
     ғؾ
     w ςετίʔυ΋ΞϓϦέʔγϣϯΛߏ੒͢ΔίʔυͷҰ෦
     ͳͷͰɺಡΈ΍͍͢ίʔυʹ͍͖ͯ͠·͠ΐ͏Ͷ
     

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