Enough Coverage To Beat The Band

The lights cut out. The crowd roars. It’s time. The band takes the stage. They’ve practiced the songs, particularly the covers. They’ve sound checked the coverage of the speakers. They know the lighting rig has the proper colored gels covering the lamps. They’re nervous, but they’ve got it all covered.

Similarly, code coverage can give you confidence before your app performs on production and also tell you how live code is used (or not used). We’ll cover how to leverage ruby’s different coverage measurement techniques in concert to assist your crew and delight your audience.

Transcript

1. Kevin Murphy
   Enough Coverage
   To Beat The Band
   

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2. Nine Inch Nails
   CC BY-NC-SA 2.0
   

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3. View Slide

4. Nine Inch Nails
   CC BY-NC-SA 2.0
   

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5. @kevin_j_m
   concert = Concert.new("RubyConf 2020")
   

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6. Coverage
   

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7. @kevin_j_m
   Kevin Murphy
   

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8. Test Coverage
   

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9. @kevin_j_m
   setlist.add_song(TheLineBeginsToBlur.new)
   

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10. @kevin_j_m
    setlist.add_song(TheLineBeginsToBlur.new)
    setlist.add_song(OneShotWayToGetThere.new)
    

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11. @kevin_j_m
    setlist.add_song(TheLineBeginsToBlur.new)
    setlist.add_song(OneShotWayToGetThere.new)
    setlist.add_song(VariousMethodsOfEscape.new)
    

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12. @kevin_j_m
    setlist.add_song(TheLineBeginsToBlur.new)
    setlist.add_song(OneShotWayToGetThere.new)
    setlist.add_song(VariousMethodsOfEscape.new)
    setlist.add_song(BranchesBones.new)
    

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13. @kevin_j_m
    setlist.add_song(TheLineBeginsToBlur.new)
    setlist.add_song(OneShotWayToGetThere.new)
    setlist.add_song(VariousMethodsOfEscape.new)
    setlist.add_song(BranchesBones.new)
    concert.setlist = setlist
    

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14. @kevin_j_m
    concert.perform
    

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15. @kevin_j_m
    setlist.songs
    [
    TheLineBeginsToBlur.new,
    OneShotWayToGetThere.new,
    VariousMethodsOfEscape.new,
    BranchesBones.new,
    ]
    

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16. The Line Begins To Blur
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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17. @kevin_j_m
    The Line Begins To Blur
    class String
    def pluck(fret:)
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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18. @kevin_j_m
    The Line Begins To Blur
    class String
    def pluck(fret:)
    if exhausted?
    break_string
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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19. @kevin_j_m
    The Line Begins To Blur
    class String
    def pluck(fret:)
    if exhausted?
    break_string
    else
    @tension -= 1
    play_note(fret)
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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20. @kevin_j_m
    The Line Begins To Blur
    class String
    def exhausted?
    @tension.negative?
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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21. @kevin_j_m
    The Line Begins To Blur
    class String
    def exhausted?
    @tension.negative? || rand(1..1000) == 3
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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22. @kevin_j_m
    The Line Begins To Blur
    class String
    def break_string
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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23. @kevin_j_m
    The Line Begins To Blur
    class String
    def break_string
    @broken = true
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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24. @kevin_j_m
    The Line Begins To Blur
    class String
    def break_string
    @broken = true
    BrokenStringSound.new
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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25. @kevin_j_m
    The Line Begins To Blur
    # lib/tour_leg_1.rb
    10.times do
    end
    

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26. @kevin_j_m
    The Line Begins To Blur
    # lib/tour_leg_1.rb
    10.times do
    concert.perform
    end
    

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27. @kevin_j_m
    The Line Begins To Blur
    require "coverage"
    

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28. @kevin_j_m
    The Line Begins To Blur
    require "coverage"
    Coverage.start(lines: true)
    

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29. @kevin_j_m
    The Line Begins To Blur
    require "coverage"
    Coverage.start(lines: true)
    load "lib/tour_leg_1.rb"
    

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30. @kevin_j_m
    The Line Begins To Blur
    require "coverage"
    Coverage.start(lines: true)
    load "lib/tour_leg_1.rb"
    result = Coverage.result
    

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31. @kevin_j_m
    The Line Begins To Blur
    {
    "lib/tour_leg_1.rb"=> {:lines => […]},
    …
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    …
    }
    

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32. @kevin_j_m
    The Line Begins To Blur
    {
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    }
    

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33. @kevin_j_m
    The Line Begins To Blur
    {
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    }
    File
    

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34. @kevin_j_m
    The Line Begins To Blur
    {
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    }
    File
    Mode
    

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35. @kevin_j_m
    The Line Begins To Blur
    {
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    }
    File
    Mode
    Line 1 Count
    

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36. @kevin_j_m
    The Line Begins To Blur
    {
    "…guitar/string.rb" => {:lines => [1, 1, 1, 1, 1, 1, nil,…]},
    }
    File
    Mode
    Line 1 Count
    Irrelevant Line 7
    

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37. @kevin_j_m
    The Line Begins To Blur
    class String
    attr_reader :tension
    attr_reader :tuning_note
    def initialize(number:, tuning_note:)
    end
    4
    5
    6
    7
    8
    Nine Inch Nails CC BY-NC-SA 2.0
    

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38. @kevin_j_m
    The Line Begins To Blur
    string_lines = result["…guitar/string.rb"][:lines]
    

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39. @kevin_j_m
    The Line Begins To Blur
    class String
    def break_string
    @broken = true
    BrokenStringSound.new
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    53
    54
    55
    56
    

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40. @kevin_j_m
    The Line Begins To Blur
    class String
    def break_string
    @broken = true
    BrokenStringSound.new
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    53
    54
    55
    56
    

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41. @kevin_j_m
    The Line Begins To Blur
    string_lines = result["…guitar/string.rb"][:lines]
    

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42. @kevin_j_m
    The Line Begins To Blur
    string_lines = result["…guitar/string.rb"][:lines]
    "Number of broken strings: #{string_lines[53]}"
    

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43. @kevin_j_m
    The Line Begins To Blur
    string_lines = result["…guitar/string.rb"][:lines]
    "Number of broken strings: #{string_lines[53]}"
    => Number of broken strings: 16
    

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44. Nine Inch Nails
    CC BY-NC-SA 2.0
    

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45. @kevin_j_m
    setlist.songs
    [
    TheLineBeginsToBlur.new,
    OneShotWayToGetThere.new,
    VariousMethodsOfEscape.new,
    BranchesBones.new,
    ]
    

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46. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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47. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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48. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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49. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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50. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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51. One(Shot) Way To Get There
    Nine Inch Nails
    CC BY-NC-SA 2.0
    drummer
    

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52. @kevin_j_m
    One(Shot) Way To Get There
    class Patch
    attr_reader :sound
    attr_reader :effect
    attr_reader :filter
    attr_reader :oscillator
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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53. @kevin_j_m
    One(Shot) Way To Get There
    class Synthesizer
    def program(note)
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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54. @kevin_j_m
    One(Shot) Way To Get There
    class Synthesizer
    def program(note)
    set_patch(note.synth_sound.patch)
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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55. @kevin_j_m
    One(Shot) Way To Get There
    class Synthesizer
    def program(note)
    set_patch(note.synth_sound.patch)
    play_key(
    key: note.synth_sound.key,
    duration: note.duration,
    )
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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56. @kevin_j_m
    One(Shot) Way To Get There
    class MoogPatchMemory
    def read(location)
    case location
    …
    end
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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57. @kevin_j_m
    One(Shot) Way To Get There
    class MoogPatchMemory
    def read(location)
    case location
    …
    end
    end
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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58. @kevin_j_m
    One(Shot) Way To Get There
    case location
    Nine Inch Nails CC BY-NC-SA 2.0
    

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59. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    Nine Inch Nails CC BY-NC-SA 2.0
    

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60. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    when :a2
    @memory[1]
    Nine Inch Nails CC BY-NC-SA 2.0
    

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61. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    when :a2
    @memory[1]
    when :b1
    @memory[2]
    Nine Inch Nails CC BY-NC-SA 2.0
    

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62. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    when :a2
    @memory[1]
    when :b1
    @memory[2]
    when :b2
    @memory[3]
    Nine Inch Nails CC BY-NC-SA 2.0
    

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63. @kevin_j_m
    # lib/festival_setlist.rb
    moog = Synthesizer.new(brand: :moog)
    One(Shot) Way To Get There
    

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64. @kevin_j_m
    # lib/festival_setlist.rb
    moog = Synthesizer.new(brand: :moog)
    moog.save_patch(location: :a1, patch: beep)
    One(Shot) Way To Get There
    

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65. @kevin_j_m
    # lib/festival_setlist.rb
    moog = Synthesizer.new(brand: :moog)
    moog.save_patch(location: :a1, patch: beep)
    moog.save_patch(location: :a2, patch: boop)
    One(Shot) Way To Get There
    

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66. @kevin_j_m
    # lib/festival_setlist.rb
    moog = Synthesizer.new(brand: :moog)
    moog.save_patch(location: :a1, patch: beep)
    moog.save_patch(location: :a2, patch: boop)
    moog.save_patch(location: :b1, patch: moog_buzz)
    One(Shot) Way To Get There
    

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67. @kevin_j_m
    # lib/festival_setlist.rb
    moog = Synthesizer.new(brand: :moog)
    moog.save_patch(location: :a1, patch: beep)
    moog.save_patch(location: :a2, patch: boop)
    moog.save_patch(location: :b1, patch: moog_buzz)
    moog.save_patch(location: :b2, patch: whirr)
    One(Shot) Way To Get There
    

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68. @kevin_j_m
    # lib/festival_setlist.rb
    concert.perform
    One(Shot) Way To Get There
    

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69. @kevin_j_m
    require "coverage"
    One(Shot) Way To Get There
    

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70. @kevin_j_m
    require "coverage"
    Coverage.start(oneshot_lines: true)
    One(Shot) Way To Get There
    

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71. @kevin_j_m
    require "coverage"
    Coverage.start(oneshot_lines: true)
    load "lib/festival_setlist.rb"
    One(Shot) Way To Get There
    

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72. @kevin_j_m
    require "coverage"
    Coverage.start(oneshot_lines: true)
    load "lib/festival_setlist.rb"
    result = Coverage.result
    One(Shot) Way To Get There
    

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73. @kevin_j_m
    {
    "lib/festival_setlist.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    "moog_patch_memory.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    }
    One(Shot) Way To Get There
    

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74. @kevin_j_m
    {
    "moog_patch_memory.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    }
    One(Shot) Way To Get There
    

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75. @kevin_j_m
    {
    "moog_patch_memory.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    }
    File
    One(Shot) Way To Get There
    

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76. @kevin_j_m
    {
    "moog_patch_memory.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    }
    File
    Mode
    One(Shot) Way To Get There
    

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77. @kevin_j_m
    {
    "moog_patch_memory.rb"=>{:oneshot_lines=>[1, 2, 3…]},
    }
    File
    Mode
    executed line numbers
    One(Shot) Way To Get There
    

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78. @kevin_j_m
    moog = result["moog_patch_memory.rb"][:oneshot_lines]
    One(Shot) Way To Get There
    

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79. @kevin_j_m
    moog = result["moog_patch_memory.rb"][:oneshot_lines]
    => [1, 2, 3, 4, 5, 7, 11, 15, 28, 41, 43, 8, 29, 31, 33, 35, 37, 12, 44, 46, 16,
    18, 20, 24]
    One(Shot) Way To Get There
    

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80. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    when :a2
    @memory[1]
    when :b1
    @memory[2]
    when :b2
    @memory[3]
    Nine Inch Nails CC BY-NC-SA 2.0
    16
    17
    18
    19
    20
    21
    22
    23
    24
    

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81. @kevin_j_m
    One(Shot) Way To Get There
    case location
    when :a1
    @memory[0]
    when :a2
    @memory[1]
    when :b1
    @memory[2]
    when :b2
    @memory[3]
    Nine Inch Nails CC BY-NC-SA 2.0
    16
    17
    18
    19
    20
    21
    22
    23
    24
    

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82. @kevin_j_m
    puts "Moog Keyboard"
    puts "=============="
    One(Shot) Way To Get There
    

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83. @kevin_j_m
    puts "Moog Keyboard"
    puts "=============="
    puts "Location A1: #{moog.include?(18) ? 'Y' : 'N'}"
    One(Shot) Way To Get There
    

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84. @kevin_j_m
    puts "Moog Keyboard"
    puts "=============="
    puts "Location A1: #{moog.include?(18) ? 'Y' : 'N'}"
    puts "Location A2: #{moog.include?(20) ? 'Y' : 'N'}"
    One(Shot) Way To Get There
    

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85. @kevin_j_m
    puts "Moog Keyboard"
    puts "=============="
    puts "Location A1: #{moog.include?(18) ? 'Y' : 'N'}"
    puts "Location A2: #{moog.include?(20) ? 'Y' : 'N'}"
    puts "Location B1: #{moog.include?(22) ? 'Y' : 'N'}"
    One(Shot) Way To Get There
    

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86. @kevin_j_m
    puts "Moog Keyboard"
    puts "=============="
    puts "Location A1: #{moog.include?(18) ? 'Y' : 'N'}"
    puts "Location A2: #{moog.include?(20) ? 'Y' : 'N'}"
    puts "Location B1: #{moog.include?(22) ? 'Y' : 'N'}"
    puts "Location B2: #{moog.include?(24) ? 'Y' : 'N'}"
    One(Shot) Way To Get There
    

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87. @kevin_j_m
    Moog Keyboard
    =============
    Location A1: Y
    Location A2: Y
    Location B1: N
    Location B2: Y
    One(Shot) Way To Get There
    

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88. @kevin_j_m
    Moog Keyboard
    =============
    Location A1: Y
    Location A2: Y
    Location B1: N
    Location B2: Y
    One(Shot) Way To Get There
    Nord Keyboard
    =============
    Location A1: Y
    Location A2: N
    Location B1: N
    Location B2: N
    

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89. @kevin_j_m
    Moog Keyboard
    =============
    Location A1: Y
    Location A2: Y
    Location B1: Y
    Location B2: Y
    One(Shot) Way To Get There
    Nord Keyboard
    =============
    Location A1: Y
    Location A2: N
    Location B1: N
    Location B2: N
    

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90. @kevin_j_m
    Moog Keyboard
    =============
    Location A1: Y
    Location A2: Y
    Location B1: Y
    Location B2: Y
    One(Shot) Way To Get There
    Nord Keyboard
    =============
    Location A1: Y
    Location A2: N
    Location B1: N
    Location B2: N
    

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91. Nine Inch Nails
    CC BY-NC-SA 2.0
    

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92. @kevin_j_m
    setlist.songs
    [
    TheLineBeginsToBlur.new,
    OneShotWayToGetThere.new,
    VariousMethodsOfEscape.new,
    BranchesBones.new,
    ]
    

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93. Various Methods Of Escape
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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95. Various Methods Of Escape
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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96. Various Methods Of Escape
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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97. Various Methods Of Escape
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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98. Various Methods Of Escape
    Nine Inch Nails
    CC BY-NC-SA 2.0
    

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99. @kevin_j_m
    Various Methods Of Escape
    class LightingController
    def trigger(note)
    end
    Nine Inch Nails CC BY-NC-SA 2.0
    

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100. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def trigger(note)
     composition = note.lighting
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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101. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def trigger(note)
     composition = note.lighting
     @powered_lights[composition.light].trigger(
     color: composition.color,
     effect: composition.effect,
     )
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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102. @kevin_j_m
     Various Methods Of Escape
     class BeamProjector
     def trigger(color:, effect:)
     end
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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103. @kevin_j_m
     Various Methods Of Escape
     class CanLight
     def trigger(color:, effect:)
     end
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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104. @kevin_j_m
     Various Methods Of Escape
     class MovingLight
     def trigger(color:, effect:)
     end
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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105. @kevin_j_m
     Various Methods Of Escape
     class Spotlight
     def trigger(color:, effect:)
     end
     end
     Nine Inch Nails CC BY-NC-SA 2.0
     

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106. @kevin_j_m
     Various Methods Of Escape
     # lib/lighting_inspection.rb
     controller = LightingController.new
     setlist.lighting = controller
     

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107. @kevin_j_m
     Various Methods Of Escape
     # lib/lighting_inspection.rb
     controller = LightingController.new
     setlist.lighting = controller
     concert.set_up
     

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108. @kevin_j_m
     Various Methods Of Escape
     # lib/lighting_inspection.rb
     controller = LightingController.new
     setlist.lighting = controller
     concert.set_up
     concert.perform
     

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109. @kevin_j_m
     Various Methods Of Escape
     # lib/lighting_inspection.rb
     controller = LightingController.new
     setlist.lighting = controller
     concert.set_up
     concert.perform
     concert.load_out
     

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110. @kevin_j_m
     Various Methods Of Escape
     require "coverage"
     

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111. @kevin_j_m
     Various Methods Of Escape
     require "coverage"
     Coverage.start(methods: true)
     

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112. @kevin_j_m
     Various Methods Of Escape
     require "coverage"
     Coverage.start(methods: true)
     load "lib/lighting_inspection.rb"
     

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113. @kevin_j_m
     Various Methods Of Escape
     require "coverage"
     Coverage.start(methods: true)
     load "lib/lighting_inspection.rb"
     result = Coverage.result
     

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114. @kevin_j_m
     Various Methods Of Escape
     "spotlight.rb"=>
     {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     "beam_projector.rb"=>
     {:methods=>{[BeamProjector, :trigger, 4, 6, 6, 9]=>0}},
     "can_light.rb"=>
     {:methods=>{[CanLight, :trigger, 4, 6, 6, 9]=>2}},
     "moving_light.rb"=>
     {:methods=>{[MovingLight, :trigger, 4, 6, 6, 9]=>6}},
     

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115. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     Various Methods Of Escape
     

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116. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     File
     Various Methods Of Escape
     

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117. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     File
     Mode
     Various Methods Of Escape
     

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118. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     File
     Mode
     Various Methods Of Escape
     method
     

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119. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     File
     Mode
     Various Methods Of Escape
     method
     count
     

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120. @kevin_j_m
     {
     "spotlight.rb"=> {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     }
     File
     Mode
     Various Methods Of Escape
     method
     count
     

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121. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     

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122. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     count
     

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123. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     class count
     

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124. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     method
     class count
     

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125. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     method
     class start line count
     

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126. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     method
     class start line
     start column
     count
     

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127. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     method
     class start line
     start column
     end line
     count
     

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128. @kevin_j_m
     [Spotlight, :trigger, 4, 6, 6, 9] => 2
     Various Methods Of Escape
     method
     class start line
     start column
     end line
     end column
     count
     

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129. @kevin_j_m
     Various Methods Of Escape
     "spotlight.rb"=>
     {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     "beam_projector.rb"=>
     {:methods=>{[BeamProjector, :trigger, 4, 6, 6, 9]=>0}},
     "can_light.rb"=>
     {:methods=>{[CanLight, :trigger, 4, 6, 6, 9]=>2}},
     "moving_light.rb"=>
     {:methods=>{[MovingLight, :trigger, 4, 6, 6, 9]=>6}},
     

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130. @kevin_j_m
     Various Methods Of Escape
     "spotlight.rb"=>
     {:methods=>{[Spotlight, :trigger, 4, 6, 6, 9]=>2}},
     "beam_projector.rb"=>
     {:methods=>{[BeamProjector, :trigger, 4, 6, 6, 9]=>0}},
     "can_light.rb"=>
     {:methods=>{[CanLight, :trigger, 4, 6, 6, 9]=>2}},
     "moving_light.rb"=>
     {:methods=>{[MovingLight, :trigger, 4, 6, 6, 9]=>6}},
     

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131. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def turn_on_lights
     @powered_lights[:beam_projector] = BeamProjector.new
     @powered_lights[:can] = CanLight.new
     @powered_lights[:moving_light] = MovingLight.new
     @powered_lights[:spotlight] = Spotlight.new
     end
     end
     

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132. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def turn_on_lights
     @powered_lights[:beam_projector] = BeamProjector.new
     @powered_lights[:can] = CanLight.new
     @powered_lights[:moving_light] = MovingLight.new
     @powered_lights[:spotlight] = Spotlight.new
     end
     end
     

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133. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def turn_on_lights
     @powered_lights[:beam_projector] = BeamProjector.new
     @powered_lights[:can] = CanLight.new
     @powered_lights[:moving_light] = MovingLight.new
     @powered_lights[:spotlight] = Spotlight.new
     end
     end
     

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134. @kevin_j_m
     Various Methods Of Escape
     class LightingController
     def turn_on_lights
     @powered_lights[:can] = CanLight.new
     @powered_lights[:moving_light] = MovingLight.new
     @powered_lights[:spotlight] = Spotlight.new
     end
     end
     

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135. Nine Inch Nails
     CC BY-NC-SA 2.0
     

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136. @kevin_j_m
     setlist.songs
     [
     TheLineBeginsToBlur.new,
     OneShotWayToGetThere.new,
     VariousMethodsOfEscape.new,
     BranchesBones.new,
     ]
     

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137. Nine Inch Nails
     CC BY-NC-SA 2.0
     

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138. Nine Inch Nails
     CC BY-NC-SA 2.0
     Nine Inch Nails
     CC BY-NC-SA 2.0
     Nine Inch Nails
     CC BY-NC-SA 2.0
     Nine Inch Nails
     CC BY-NC-SA 2.0
     Nine Inch Nails
     CC BY-NC-SA 2.0
     

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139. @kevin_j_m
     Branches/Bones
     # lib/rehearsal.rb
     song = BranchesBones.new
     

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140. @kevin_j_m
     Branches/Bones
     # lib/rehearsal.rb
     song = BranchesBones.new
     song.performers = band
     

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141. @kevin_j_m
     Branches/Bones
     # lib/rehearsal.rb
     song = BranchesBones.new
     song.performers = band
     song.play
     

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142. @kevin_j_m
     Branches/Bones
     require "coverage"
     

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143. @kevin_j_m
     Branches/Bones
     require "coverage"
     Coverage.start(:all)
     

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144. @kevin_j_m
     Branches/Bones
     require "coverage"
     Coverage.start(:all)
     load "lib/rehearsal.rb"
     

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145. @kevin_j_m
     Branches/Bones
     require "coverage"
     Coverage.start(:all)
     load "lib/rehearsal.rb"
     result = Coverage.result
     

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146. @kevin_j_m
     Branches/Bones
     "branches_bones.rb"=>{
     :lines=>[1, 1, 1, 1, 1, nil, nil, nil, nil, nil, 1, nil, 1, nil, 1, nil, nil, nil, 1, nil, 1, nil, nil, nil, 1, nil,
     1, nil, nil, nil, nil, nil, 1, 2, nil, nil, 2, nil, nil, nil, nil, 2, nil, 2, 8, nil, nil, nil, nil, nil],
     :branches=>{[:if, 0, 34, 25, 34, 67]=>{[:then, 1, 34, 60, 34, 62]=>0, [:else, 2, 34, 65, 34,
     67]=>2}, [:if, 3, 42, 18, 42, 99]=>{[:then, 4, 42, 41, 42, 75]=>0, [:else, 5, 42, 78, 42, 99]=>2}},
     :methods=>{
     [RubyCoverBand::Songs::BranchesBones, :chorus, 33, 6, 47, 9]=>2
     [RubyCoverBand::Songs::BranchesBones, :outro, 25, 6, 29, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :verse_2, 19, 6, 23, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :verse_1, 13, 6, 17, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :initialize, 4, 6, 9, 9]=>1}},
     

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147. @kevin_j_m
     Branches/Bones
     "branches_bones.rb"=>{
     :lines=>[1, 1, 1, 1, 1, nil, nil, nil, nil, nil, 1, nil, 1, nil, 1, nil, nil, nil, 1, nil, 1, nil, nil, nil, 1, nil,
     1, nil, nil, nil, nil, nil, 1, 2, nil, nil, 2, nil, nil, nil, nil, 2, nil, 2, 8, nil, nil, nil, nil, nil],
     :branches=>{[:if, 0, 34, 25, 34, 67]=>{[:then, 1, 34, 60, 34, 62]=>0, [:else, 2, 34, 65, 34,
     67]=>2}, [:if, 3, 42, 18, 42, 99]=>{[:then, 4, 42, 41, 42, 75]=>0, [:else, 5, 42, 78, 42, 99]=>2}},
     :methods=>{
     [RubyCoverBand::Songs::BranchesBones, :chorus, 33, 6, 47, 9]=>2
     [RubyCoverBand::Songs::BranchesBones, :outro, 25, 6, 29, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :verse_2, 19, 6, 23, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :verse_1, 13, 6, 17, 9]=>1,
     [RubyCoverBand::Songs::BranchesBones, :initialize, 4, 6, 9, 9]=>1}},
     

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148. @kevin_j_m
     Branches/Bones
     song_coverage = result["branches_bones.rb"]
     song_coverage.keys
     

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149. @kevin_j_m
     Branches/Bones
     song_coverage = result["branches_bones.rb"]
     song_coverage.keys
     => [:lines, :methods, :branches]
     

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150. @kevin_j_m
     Branches/Bones
     song_coverage[:lines].include?(0)
     => false
     

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151. @kevin_j_m
     Branches/Bones
     song_coverage[:methods].values.include?(0)
     => false
     

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152. @kevin_j_m
     Branches/Bones
     song_coverage[:branches]
     => {[:if, 0, 34, 25, 34, 67]=>{
     [:then, 1, 34, 60, 34, 62]=>0,
     [:else, 2, 34, 65, 34, 67]=>2,
     }}
     

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153. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     

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154. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File
     

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155. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File mode
     

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156. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File mode
     conditional
     

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157. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File mode
     conditional
     branch
     

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158. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File mode
     conditional
     branch
     branch
     

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159. @kevin_j_m
     Branches/Bones
     {
     "branches_bones.rb" => { :branches =>
     {[:if, 0, 34, 25, 34, 67] => {
     [:then, 1, 34, 60, 34, 62] => 0,
     [:else, 2, 34, 65, 34, 67] => 2,
     }}
     }
     }
     File mode
     conditional
     branch
     branch
     

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160. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     

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161. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     count
     

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162. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch count
     

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163. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch count
     id
     

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164. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch start line count
     id
     

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165. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch start line
     start column
     count
     id
     

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166. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch start line
     start column
     end line
     count
     id
     

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167. @kevin_j_m
     Branches/Bones
     [:then, 1, 34, 60, 34, 62] => 0
     branch start line
     start column
     end line
     end column
     count
     id
     

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168. @kevin_j_m
     Branches/Bones
     class BranchesBones < Song
     def chorus(number)
     echo_intensity = number.positive? && number.even? ? 10 : 30
     …
     Lyric.new(line: line, effect: :echo, effect_level: echo_intensity)
     32
     33
     34
     35
     60
     62
     

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169. @kevin_j_m
     Branches/Bones
     class BranchesBones < Song
     def initialize
     notes = verse_1 + chorus(0) + verse_2 + chorus(1) + outro
     end
     def chorus(number)
     echo_intensity = number.positive? && number.even? ? 10 : 30
     end
     

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170. @kevin_j_m
     Branches/Bones
     class BranchesBones < Song
     def initialize
     notes = verse_1 + chorus(0) + verse_2 + chorus(1) + outro
     end
     def chorus(number)
     echo_intensity = number.positive? && number.even? ? 10 : 30
     end
     

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171. @kevin_j_m
     Branches/Bones
     class BranchesBones < Song
     def initialize
     notes = verse_1 + chorus(1) + verse_2 + chorus(2) + outro
     end
     def chorus(number)
     echo_intensity = number.positive? && number.even? ? 10 : 30
     end
     

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172. @kevin_j_m
     Branches/Bones
     song_coverage[:branches]
     => {[:if, 0, 34, 25, 34, 67]=>{
     [:then, 1, 34, 60, 34, 62]=>1,
     [:else, 2, 34, 65, 34, 67]=>1,
     }}
     

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173. Branches/Bones
     Nine Inch Nails
     CC BY-NC-SA 2.0
     

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174. encore
     

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175. @kevin_j_m
     {
     }
     coverage.summary
     

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176. @kevin_j_m
     {
     lines: "how many times was each line executed?",
     }
     coverage.summary
     

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177. @kevin_j_m
     {
     lines: "how many times was each line executed?",
     oneshot_lines: "which lines were executed?",
     }
     coverage.summary
     

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178. @kevin_j_m
     {
     lines: "how many times was each line executed?",
     oneshot_lines: "which lines were executed?",
     methods: "how many times was each method executed?",
     }
     coverage.summary
     

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179. @kevin_j_m
     {
     lines: "how many times was each line executed?",
     oneshot_lines: "which lines were executed?",
     methods: "how many times was each method executed?",
     branches: "how many times was each branch executed?",
     }
     coverage.summary
     

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180. @kevin_j_m
     Supporting Instruments
     Nine Inch Nails CC BY-NC-SA 2.0
     SimpleCov
     Coverband
     

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181. @kevin_j_m
     https://kevin-j-m.github.io/coverage
     #_rc_talk-enough-coverage-to-beat-the-band
     Nine Inch Nails CC BY-NC-SA 2.0
     

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