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jacobrale's solution

to Beer Song in the Ruby Track

Published at Aug 29 2020 · 0 comments
Instructions
Test suite
Solution

Recite the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.

Note that not all verses are identical.

99 bottles of beer on the wall, 99 bottles of beer.
Take one down and pass it around, 98 bottles of beer on the wall.

98 bottles of beer on the wall, 98 bottles of beer.
Take one down and pass it around, 97 bottles of beer on the wall.

97 bottles of beer on the wall, 97 bottles of beer.
Take one down and pass it around, 96 bottles of beer on the wall.

96 bottles of beer on the wall, 96 bottles of beer.
Take one down and pass it around, 95 bottles of beer on the wall.

95 bottles of beer on the wall, 95 bottles of beer.
Take one down and pass it around, 94 bottles of beer on the wall.

94 bottles of beer on the wall, 94 bottles of beer.
Take one down and pass it around, 93 bottles of beer on the wall.

93 bottles of beer on the wall, 93 bottles of beer.
Take one down and pass it around, 92 bottles of beer on the wall.

92 bottles of beer on the wall, 92 bottles of beer.
Take one down and pass it around, 91 bottles of beer on the wall.

91 bottles of beer on the wall, 91 bottles of beer.
Take one down and pass it around, 90 bottles of beer on the wall.

90 bottles of beer on the wall, 90 bottles of beer.
Take one down and pass it around, 89 bottles of beer on the wall.

89 bottles of beer on the wall, 89 bottles of beer.
Take one down and pass it around, 88 bottles of beer on the wall.

88 bottles of beer on the wall, 88 bottles of beer.
Take one down and pass it around, 87 bottles of beer on the wall.

87 bottles of beer on the wall, 87 bottles of beer.
Take one down and pass it around, 86 bottles of beer on the wall.

86 bottles of beer on the wall, 86 bottles of beer.
Take one down and pass it around, 85 bottles of beer on the wall.

85 bottles of beer on the wall, 85 bottles of beer.
Take one down and pass it around, 84 bottles of beer on the wall.

84 bottles of beer on the wall, 84 bottles of beer.
Take one down and pass it around, 83 bottles of beer on the wall.

83 bottles of beer on the wall, 83 bottles of beer.
Take one down and pass it around, 82 bottles of beer on the wall.

82 bottles of beer on the wall, 82 bottles of beer.
Take one down and pass it around, 81 bottles of beer on the wall.

81 bottles of beer on the wall, 81 bottles of beer.
Take one down and pass it around, 80 bottles of beer on the wall.

80 bottles of beer on the wall, 80 bottles of beer.
Take one down and pass it around, 79 bottles of beer on the wall.

79 bottles of beer on the wall, 79 bottles of beer.
Take one down and pass it around, 78 bottles of beer on the wall.

78 bottles of beer on the wall, 78 bottles of beer.
Take one down and pass it around, 77 bottles of beer on the wall.

77 bottles of beer on the wall, 77 bottles of beer.
Take one down and pass it around, 76 bottles of beer on the wall.

76 bottles of beer on the wall, 76 bottles of beer.
Take one down and pass it around, 75 bottles of beer on the wall.

75 bottles of beer on the wall, 75 bottles of beer.
Take one down and pass it around, 74 bottles of beer on the wall.

74 bottles of beer on the wall, 74 bottles of beer.
Take one down and pass it around, 73 bottles of beer on the wall.

73 bottles of beer on the wall, 73 bottles of beer.
Take one down and pass it around, 72 bottles of beer on the wall.

72 bottles of beer on the wall, 72 bottles of beer.
Take one down and pass it around, 71 bottles of beer on the wall.

71 bottles of beer on the wall, 71 bottles of beer.
Take one down and pass it around, 70 bottles of beer on the wall.

70 bottles of beer on the wall, 70 bottles of beer.
Take one down and pass it around, 69 bottles of beer on the wall.

69 bottles of beer on the wall, 69 bottles of beer.
Take one down and pass it around, 68 bottles of beer on the wall.

68 bottles of beer on the wall, 68 bottles of beer.
Take one down and pass it around, 67 bottles of beer on the wall.

67 bottles of beer on the wall, 67 bottles of beer.
Take one down and pass it around, 66 bottles of beer on the wall.

66 bottles of beer on the wall, 66 bottles of beer.
Take one down and pass it around, 65 bottles of beer on the wall.

65 bottles of beer on the wall, 65 bottles of beer.
Take one down and pass it around, 64 bottles of beer on the wall.

64 bottles of beer on the wall, 64 bottles of beer.
Take one down and pass it around, 63 bottles of beer on the wall.

63 bottles of beer on the wall, 63 bottles of beer.
Take one down and pass it around, 62 bottles of beer on the wall.

62 bottles of beer on the wall, 62 bottles of beer.
Take one down and pass it around, 61 bottles of beer on the wall.

61 bottles of beer on the wall, 61 bottles of beer.
Take one down and pass it around, 60 bottles of beer on the wall.

60 bottles of beer on the wall, 60 bottles of beer.
Take one down and pass it around, 59 bottles of beer on the wall.

59 bottles of beer on the wall, 59 bottles of beer.
Take one down and pass it around, 58 bottles of beer on the wall.

58 bottles of beer on the wall, 58 bottles of beer.
Take one down and pass it around, 57 bottles of beer on the wall.

57 bottles of beer on the wall, 57 bottles of beer.
Take one down and pass it around, 56 bottles of beer on the wall.

56 bottles of beer on the wall, 56 bottles of beer.
Take one down and pass it around, 55 bottles of beer on the wall.

55 bottles of beer on the wall, 55 bottles of beer.
Take one down and pass it around, 54 bottles of beer on the wall.

54 bottles of beer on the wall, 54 bottles of beer.
Take one down and pass it around, 53 bottles of beer on the wall.

53 bottles of beer on the wall, 53 bottles of beer.
Take one down and pass it around, 52 bottles of beer on the wall.

52 bottles of beer on the wall, 52 bottles of beer.
Take one down and pass it around, 51 bottles of beer on the wall.

51 bottles of beer on the wall, 51 bottles of beer.
Take one down and pass it around, 50 bottles of beer on the wall.

50 bottles of beer on the wall, 50 bottles of beer.
Take one down and pass it around, 49 bottles of beer on the wall.

49 bottles of beer on the wall, 49 bottles of beer.
Take one down and pass it around, 48 bottles of beer on the wall.

48 bottles of beer on the wall, 48 bottles of beer.
Take one down and pass it around, 47 bottles of beer on the wall.

47 bottles of beer on the wall, 47 bottles of beer.
Take one down and pass it around, 46 bottles of beer on the wall.

46 bottles of beer on the wall, 46 bottles of beer.
Take one down and pass it around, 45 bottles of beer on the wall.

45 bottles of beer on the wall, 45 bottles of beer.
Take one down and pass it around, 44 bottles of beer on the wall.

44 bottles of beer on the wall, 44 bottles of beer.
Take one down and pass it around, 43 bottles of beer on the wall.

43 bottles of beer on the wall, 43 bottles of beer.
Take one down and pass it around, 42 bottles of beer on the wall.

42 bottles of beer on the wall, 42 bottles of beer.
Take one down and pass it around, 41 bottles of beer on the wall.

41 bottles of beer on the wall, 41 bottles of beer.
Take one down and pass it around, 40 bottles of beer on the wall.

40 bottles of beer on the wall, 40 bottles of beer.
Take one down and pass it around, 39 bottles of beer on the wall.

39 bottles of beer on the wall, 39 bottles of beer.
Take one down and pass it around, 38 bottles of beer on the wall.

38 bottles of beer on the wall, 38 bottles of beer.
Take one down and pass it around, 37 bottles of beer on the wall.

37 bottles of beer on the wall, 37 bottles of beer.
Take one down and pass it around, 36 bottles of beer on the wall.

36 bottles of beer on the wall, 36 bottles of beer.
Take one down and pass it around, 35 bottles of beer on the wall.

35 bottles of beer on the wall, 35 bottles of beer.
Take one down and pass it around, 34 bottles of beer on the wall.

34 bottles of beer on the wall, 34 bottles of beer.
Take one down and pass it around, 33 bottles of beer on the wall.

33 bottles of beer on the wall, 33 bottles of beer.
Take one down and pass it around, 32 bottles of beer on the wall.

32 bottles of beer on the wall, 32 bottles of beer.
Take one down and pass it around, 31 bottles of beer on the wall.

31 bottles of beer on the wall, 31 bottles of beer.
Take one down and pass it around, 30 bottles of beer on the wall.

30 bottles of beer on the wall, 30 bottles of beer.
Take one down and pass it around, 29 bottles of beer on the wall.

29 bottles of beer on the wall, 29 bottles of beer.
Take one down and pass it around, 28 bottles of beer on the wall.

28 bottles of beer on the wall, 28 bottles of beer.
Take one down and pass it around, 27 bottles of beer on the wall.

27 bottles of beer on the wall, 27 bottles of beer.
Take one down and pass it around, 26 bottles of beer on the wall.

26 bottles of beer on the wall, 26 bottles of beer.
Take one down and pass it around, 25 bottles of beer on the wall.

25 bottles of beer on the wall, 25 bottles of beer.
Take one down and pass it around, 24 bottles of beer on the wall.

24 bottles of beer on the wall, 24 bottles of beer.
Take one down and pass it around, 23 bottles of beer on the wall.

23 bottles of beer on the wall, 23 bottles of beer.
Take one down and pass it around, 22 bottles of beer on the wall.

22 bottles of beer on the wall, 22 bottles of beer.
Take one down and pass it around, 21 bottles of beer on the wall.

21 bottles of beer on the wall, 21 bottles of beer.
Take one down and pass it around, 20 bottles of beer on the wall.

20 bottles of beer on the wall, 20 bottles of beer.
Take one down and pass it around, 19 bottles of beer on the wall.

19 bottles of beer on the wall, 19 bottles of beer.
Take one down and pass it around, 18 bottles of beer on the wall.

18 bottles of beer on the wall, 18 bottles of beer.
Take one down and pass it around, 17 bottles of beer on the wall.

17 bottles of beer on the wall, 17 bottles of beer.
Take one down and pass it around, 16 bottles of beer on the wall.

16 bottles of beer on the wall, 16 bottles of beer.
Take one down and pass it around, 15 bottles of beer on the wall.

15 bottles of beer on the wall, 15 bottles of beer.
Take one down and pass it around, 14 bottles of beer on the wall.

14 bottles of beer on the wall, 14 bottles of beer.
Take one down and pass it around, 13 bottles of beer on the wall.

13 bottles of beer on the wall, 13 bottles of beer.
Take one down and pass it around, 12 bottles of beer on the wall.

12 bottles of beer on the wall, 12 bottles of beer.
Take one down and pass it around, 11 bottles of beer on the wall.

11 bottles of beer on the wall, 11 bottles of beer.
Take one down and pass it around, 10 bottles of beer on the wall.

10 bottles of beer on the wall, 10 bottles of beer.
Take one down and pass it around, 9 bottles of beer on the wall.

9 bottles of beer on the wall, 9 bottles of beer.
Take one down and pass it around, 8 bottles of beer on the wall.

8 bottles of beer on the wall, 8 bottles of beer.
Take one down and pass it around, 7 bottles of beer on the wall.

7 bottles of beer on the wall, 7 bottles of beer.
Take one down and pass it around, 6 bottles of beer on the wall.

6 bottles of beer on the wall, 6 bottles of beer.
Take one down and pass it around, 5 bottles of beer on the wall.

5 bottles of beer on the wall, 5 bottles of beer.
Take one down and pass it around, 4 bottles of beer on the wall.

4 bottles of beer on the wall, 4 bottles of beer.
Take one down and pass it around, 3 bottles of beer on the wall.

3 bottles of beer on the wall, 3 bottles of beer.
Take one down and pass it around, 2 bottles of beer on the wall.

2 bottles of beer on the wall, 2 bottles of beer.
Take one down and pass it around, 1 bottle of beer on the wall.

1 bottle of beer on the wall, 1 bottle of beer.
Take it down and pass it around, no more bottles of beer on the wall.

No more bottles of beer on the wall, no more bottles of beer.
Go to the store and buy some more, 99 bottles of beer on the wall.

For bonus points

Did you get the tests passing and the code clean? If you want to, these are some additional things you could try:

  • Remove as much duplication as you possibly can.
  • Optimize for readability, even if it means introducing duplication.
  • If you've removed all the duplication, do you have a lot of conditionals? Try replacing the conditionals with polymorphism, if it applies in this language. How readable is it?

Then please share your thoughts in a comment on the submission. Did this experiment make the code better? Worse? Did you learn anything from it?


For installation and learning resources, refer to the Ruby resources page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby beer_song_test.rb

To include color from the command line:

ruby -r minitest/pride beer_song_test.rb

Source

Learn to Program by Chris Pine http://pine.fm/LearnToProgram/?Chapter=06

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

beer_song_test.rb

require 'minitest/autorun'
require_relative 'beer_song'

# Common test data version: 2.1.0 87a334d
class BeerSongTest < Minitest::Test
  def test_first_generic_verse
    # skip
    expected = <<~TEXT
    99 bottles of beer on the wall, 99 bottles of beer.
    Take one down and pass it around, 98 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(99, 1)
  end

  def test_last_generic_verse
    skip
    expected = <<~TEXT
    3 bottles of beer on the wall, 3 bottles of beer.
    Take one down and pass it around, 2 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(3, 1)
  end

  def test_verse_with_2_bottles
    skip
    expected = <<~TEXT
    2 bottles of beer on the wall, 2 bottles of beer.
    Take one down and pass it around, 1 bottle of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(2, 1)
  end

  def test_verse_with_1_bottle
    skip
    expected = <<~TEXT
    1 bottle of beer on the wall, 1 bottle of beer.
    Take it down and pass it around, no more bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(1, 1)
  end

  def test_verse_with_0_bottles
    skip
    expected = <<~TEXT
    No more bottles of beer on the wall, no more bottles of beer.
    Go to the store and buy some more, 99 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(0, 1)
  end

  def test_first_two_verses
    skip
    expected = <<~TEXT
    99 bottles of beer on the wall, 99 bottles of beer.
    Take one down and pass it around, 98 bottles of beer on the wall.

    98 bottles of beer on the wall, 98 bottles of beer.
    Take one down and pass it around, 97 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(99, 2)
  end

  def test_last_three_verses
    skip
    expected = <<~TEXT
    2 bottles of beer on the wall, 2 bottles of beer.
    Take one down and pass it around, 1 bottle of beer on the wall.

    1 bottle of beer on the wall, 1 bottle of beer.
    Take it down and pass it around, no more bottles of beer on the wall.

    No more bottles of beer on the wall, no more bottles of beer.
    Go to the store and buy some more, 99 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(2, 3)
  end

  def test_all_verses
    skip
    expected = <<~TEXT
    99 bottles of beer on the wall, 99 bottles of beer.
    Take one down and pass it around, 98 bottles of beer on the wall.

    98 bottles of beer on the wall, 98 bottles of beer.
    Take one down and pass it around, 97 bottles of beer on the wall.

    97 bottles of beer on the wall, 97 bottles of beer.
    Take one down and pass it around, 96 bottles of beer on the wall.

    96 bottles of beer on the wall, 96 bottles of beer.
    Take one down and pass it around, 95 bottles of beer on the wall.

    95 bottles of beer on the wall, 95 bottles of beer.
    Take one down and pass it around, 94 bottles of beer on the wall.

    94 bottles of beer on the wall, 94 bottles of beer.
    Take one down and pass it around, 93 bottles of beer on the wall.

    93 bottles of beer on the wall, 93 bottles of beer.
    Take one down and pass it around, 92 bottles of beer on the wall.

    92 bottles of beer on the wall, 92 bottles of beer.
    Take one down and pass it around, 91 bottles of beer on the wall.

    91 bottles of beer on the wall, 91 bottles of beer.
    Take one down and pass it around, 90 bottles of beer on the wall.

    90 bottles of beer on the wall, 90 bottles of beer.
    Take one down and pass it around, 89 bottles of beer on the wall.

    89 bottles of beer on the wall, 89 bottles of beer.
    Take one down and pass it around, 88 bottles of beer on the wall.

    88 bottles of beer on the wall, 88 bottles of beer.
    Take one down and pass it around, 87 bottles of beer on the wall.

    87 bottles of beer on the wall, 87 bottles of beer.
    Take one down and pass it around, 86 bottles of beer on the wall.

    86 bottles of beer on the wall, 86 bottles of beer.
    Take one down and pass it around, 85 bottles of beer on the wall.

    85 bottles of beer on the wall, 85 bottles of beer.
    Take one down and pass it around, 84 bottles of beer on the wall.

    84 bottles of beer on the wall, 84 bottles of beer.
    Take one down and pass it around, 83 bottles of beer on the wall.

    83 bottles of beer on the wall, 83 bottles of beer.
    Take one down and pass it around, 82 bottles of beer on the wall.

    82 bottles of beer on the wall, 82 bottles of beer.
    Take one down and pass it around, 81 bottles of beer on the wall.

    81 bottles of beer on the wall, 81 bottles of beer.
    Take one down and pass it around, 80 bottles of beer on the wall.

    80 bottles of beer on the wall, 80 bottles of beer.
    Take one down and pass it around, 79 bottles of beer on the wall.

    79 bottles of beer on the wall, 79 bottles of beer.
    Take one down and pass it around, 78 bottles of beer on the wall.

    78 bottles of beer on the wall, 78 bottles of beer.
    Take one down and pass it around, 77 bottles of beer on the wall.

    77 bottles of beer on the wall, 77 bottles of beer.
    Take one down and pass it around, 76 bottles of beer on the wall.

    76 bottles of beer on the wall, 76 bottles of beer.
    Take one down and pass it around, 75 bottles of beer on the wall.

    75 bottles of beer on the wall, 75 bottles of beer.
    Take one down and pass it around, 74 bottles of beer on the wall.

    74 bottles of beer on the wall, 74 bottles of beer.
    Take one down and pass it around, 73 bottles of beer on the wall.

    73 bottles of beer on the wall, 73 bottles of beer.
    Take one down and pass it around, 72 bottles of beer on the wall.

    72 bottles of beer on the wall, 72 bottles of beer.
    Take one down and pass it around, 71 bottles of beer on the wall.

    71 bottles of beer on the wall, 71 bottles of beer.
    Take one down and pass it around, 70 bottles of beer on the wall.

    70 bottles of beer on the wall, 70 bottles of beer.
    Take one down and pass it around, 69 bottles of beer on the wall.

    69 bottles of beer on the wall, 69 bottles of beer.
    Take one down and pass it around, 68 bottles of beer on the wall.

    68 bottles of beer on the wall, 68 bottles of beer.
    Take one down and pass it around, 67 bottles of beer on the wall.

    67 bottles of beer on the wall, 67 bottles of beer.
    Take one down and pass it around, 66 bottles of beer on the wall.

    66 bottles of beer on the wall, 66 bottles of beer.
    Take one down and pass it around, 65 bottles of beer on the wall.

    65 bottles of beer on the wall, 65 bottles of beer.
    Take one down and pass it around, 64 bottles of beer on the wall.

    64 bottles of beer on the wall, 64 bottles of beer.
    Take one down and pass it around, 63 bottles of beer on the wall.

    63 bottles of beer on the wall, 63 bottles of beer.
    Take one down and pass it around, 62 bottles of beer on the wall.

    62 bottles of beer on the wall, 62 bottles of beer.
    Take one down and pass it around, 61 bottles of beer on the wall.

    61 bottles of beer on the wall, 61 bottles of beer.
    Take one down and pass it around, 60 bottles of beer on the wall.

    60 bottles of beer on the wall, 60 bottles of beer.
    Take one down and pass it around, 59 bottles of beer on the wall.

    59 bottles of beer on the wall, 59 bottles of beer.
    Take one down and pass it around, 58 bottles of beer on the wall.

    58 bottles of beer on the wall, 58 bottles of beer.
    Take one down and pass it around, 57 bottles of beer on the wall.

    57 bottles of beer on the wall, 57 bottles of beer.
    Take one down and pass it around, 56 bottles of beer on the wall.

    56 bottles of beer on the wall, 56 bottles of beer.
    Take one down and pass it around, 55 bottles of beer on the wall.

    55 bottles of beer on the wall, 55 bottles of beer.
    Take one down and pass it around, 54 bottles of beer on the wall.

    54 bottles of beer on the wall, 54 bottles of beer.
    Take one down and pass it around, 53 bottles of beer on the wall.

    53 bottles of beer on the wall, 53 bottles of beer.
    Take one down and pass it around, 52 bottles of beer on the wall.

    52 bottles of beer on the wall, 52 bottles of beer.
    Take one down and pass it around, 51 bottles of beer on the wall.

    51 bottles of beer on the wall, 51 bottles of beer.
    Take one down and pass it around, 50 bottles of beer on the wall.

    50 bottles of beer on the wall, 50 bottles of beer.
    Take one down and pass it around, 49 bottles of beer on the wall.

    49 bottles of beer on the wall, 49 bottles of beer.
    Take one down and pass it around, 48 bottles of beer on the wall.

    48 bottles of beer on the wall, 48 bottles of beer.
    Take one down and pass it around, 47 bottles of beer on the wall.

    47 bottles of beer on the wall, 47 bottles of beer.
    Take one down and pass it around, 46 bottles of beer on the wall.

    46 bottles of beer on the wall, 46 bottles of beer.
    Take one down and pass it around, 45 bottles of beer on the wall.

    45 bottles of beer on the wall, 45 bottles of beer.
    Take one down and pass it around, 44 bottles of beer on the wall.

    44 bottles of beer on the wall, 44 bottles of beer.
    Take one down and pass it around, 43 bottles of beer on the wall.

    43 bottles of beer on the wall, 43 bottles of beer.
    Take one down and pass it around, 42 bottles of beer on the wall.

    42 bottles of beer on the wall, 42 bottles of beer.
    Take one down and pass it around, 41 bottles of beer on the wall.

    41 bottles of beer on the wall, 41 bottles of beer.
    Take one down and pass it around, 40 bottles of beer on the wall.

    40 bottles of beer on the wall, 40 bottles of beer.
    Take one down and pass it around, 39 bottles of beer on the wall.

    39 bottles of beer on the wall, 39 bottles of beer.
    Take one down and pass it around, 38 bottles of beer on the wall.

    38 bottles of beer on the wall, 38 bottles of beer.
    Take one down and pass it around, 37 bottles of beer on the wall.

    37 bottles of beer on the wall, 37 bottles of beer.
    Take one down and pass it around, 36 bottles of beer on the wall.

    36 bottles of beer on the wall, 36 bottles of beer.
    Take one down and pass it around, 35 bottles of beer on the wall.

    35 bottles of beer on the wall, 35 bottles of beer.
    Take one down and pass it around, 34 bottles of beer on the wall.

    34 bottles of beer on the wall, 34 bottles of beer.
    Take one down and pass it around, 33 bottles of beer on the wall.

    33 bottles of beer on the wall, 33 bottles of beer.
    Take one down and pass it around, 32 bottles of beer on the wall.

    32 bottles of beer on the wall, 32 bottles of beer.
    Take one down and pass it around, 31 bottles of beer on the wall.

    31 bottles of beer on the wall, 31 bottles of beer.
    Take one down and pass it around, 30 bottles of beer on the wall.

    30 bottles of beer on the wall, 30 bottles of beer.
    Take one down and pass it around, 29 bottles of beer on the wall.

    29 bottles of beer on the wall, 29 bottles of beer.
    Take one down and pass it around, 28 bottles of beer on the wall.

    28 bottles of beer on the wall, 28 bottles of beer.
    Take one down and pass it around, 27 bottles of beer on the wall.

    27 bottles of beer on the wall, 27 bottles of beer.
    Take one down and pass it around, 26 bottles of beer on the wall.

    26 bottles of beer on the wall, 26 bottles of beer.
    Take one down and pass it around, 25 bottles of beer on the wall.

    25 bottles of beer on the wall, 25 bottles of beer.
    Take one down and pass it around, 24 bottles of beer on the wall.

    24 bottles of beer on the wall, 24 bottles of beer.
    Take one down and pass it around, 23 bottles of beer on the wall.

    23 bottles of beer on the wall, 23 bottles of beer.
    Take one down and pass it around, 22 bottles of beer on the wall.

    22 bottles of beer on the wall, 22 bottles of beer.
    Take one down and pass it around, 21 bottles of beer on the wall.

    21 bottles of beer on the wall, 21 bottles of beer.
    Take one down and pass it around, 20 bottles of beer on the wall.

    20 bottles of beer on the wall, 20 bottles of beer.
    Take one down and pass it around, 19 bottles of beer on the wall.

    19 bottles of beer on the wall, 19 bottles of beer.
    Take one down and pass it around, 18 bottles of beer on the wall.

    18 bottles of beer on the wall, 18 bottles of beer.
    Take one down and pass it around, 17 bottles of beer on the wall.

    17 bottles of beer on the wall, 17 bottles of beer.
    Take one down and pass it around, 16 bottles of beer on the wall.

    16 bottles of beer on the wall, 16 bottles of beer.
    Take one down and pass it around, 15 bottles of beer on the wall.

    15 bottles of beer on the wall, 15 bottles of beer.
    Take one down and pass it around, 14 bottles of beer on the wall.

    14 bottles of beer on the wall, 14 bottles of beer.
    Take one down and pass it around, 13 bottles of beer on the wall.

    13 bottles of beer on the wall, 13 bottles of beer.
    Take one down and pass it around, 12 bottles of beer on the wall.

    12 bottles of beer on the wall, 12 bottles of beer.
    Take one down and pass it around, 11 bottles of beer on the wall.

    11 bottles of beer on the wall, 11 bottles of beer.
    Take one down and pass it around, 10 bottles of beer on the wall.

    10 bottles of beer on the wall, 10 bottles of beer.
    Take one down and pass it around, 9 bottles of beer on the wall.

    9 bottles of beer on the wall, 9 bottles of beer.
    Take one down and pass it around, 8 bottles of beer on the wall.

    8 bottles of beer on the wall, 8 bottles of beer.
    Take one down and pass it around, 7 bottles of beer on the wall.

    7 bottles of beer on the wall, 7 bottles of beer.
    Take one down and pass it around, 6 bottles of beer on the wall.

    6 bottles of beer on the wall, 6 bottles of beer.
    Take one down and pass it around, 5 bottles of beer on the wall.

    5 bottles of beer on the wall, 5 bottles of beer.
    Take one down and pass it around, 4 bottles of beer on the wall.

    4 bottles of beer on the wall, 4 bottles of beer.
    Take one down and pass it around, 3 bottles of beer on the wall.

    3 bottles of beer on the wall, 3 bottles of beer.
    Take one down and pass it around, 2 bottles of beer on the wall.

    2 bottles of beer on the wall, 2 bottles of beer.
    Take one down and pass it around, 1 bottle of beer on the wall.

    1 bottle of beer on the wall, 1 bottle of beer.
    Take it down and pass it around, no more bottles of beer on the wall.

    No more bottles of beer on the wall, no more bottles of beer.
    Go to the store and buy some more, 99 bottles of beer on the wall.
    TEXT
    assert_equal expected, BeerSong.recite(99, 100)
  end
end
# frozen_string_literal: true

=begin
Write your code for the 'Beer Song' exercise in this file. Make the tests in
`beer_song_test.rb` pass.

To get started with TDD, see the `README.md` file in your
`ruby/beer-song` directory.
=end

BEVERAGE = 'beer'
CONTAINER = 'bottle'
TOTAL_CONTAINERS = 999 # Not really need only used in one place
STORAGE_PHRASE = 'on the wall'
BEV_PLUS_STORAGE = "#{BEVERAGE} #{STORAGE_PHRASE}"

# CountdownSong
class CountdownSong
  attr_accessor :verse_template, :min, :max  # why do we need these?  They're setup in the initialzer, not going to need to read them.

  def initialize(verse_template: BottleVerse, max: TOTAL_CONTAINERS, min: 0 )
    @max, @min = max, min
    @verse_template = verse_template
  end

  def verses(*range_of_bottles)
    range_of_bottles[0].downto(range_of_bottles[1]).collect { |i| verse(i) }.join("\n")
  end

  def verse(count)
    @verse_template.lyrics(count)
  end

  def song
    verses(max, min)
  end
end

# A class that will know about the number of bottles
class BottleNumber
  attr_accessor :bottle_number

  class <<self
    attr_accessor :registry
  end

  def self.for(number)
    @registry.find { |candidate| candidate.handles?(number) }.new(number)
  end

  def for1(number)
    registry.find { |candidate| candidate.handles?(number) }.new(number)
  end

  def self.registry
    @registry ||= [BottleNumber]
  end

  def self.register(candidate)
    registry.prepend(candidate)
  end

  def self.inherited(subclass)
    # self.register(subclass)
    register(subclass)
  end

  def self.handles?(number)
    # Need the same method signature.
    true
  end

  def initialize(bottle_number)
    @bottle_number = bottle_number
  end

  def to_s
    # A bit of a sham, but on the other hand, maybe not.  It's telling it two main characterizes: what it is and which quantity it is.
    quantity_and_container
  end

  def successor
    BottleNumber.for(bottle_number - 1)
    # BottleNumber.new(bottle_number - 1)
  end

  def quantity
    bottle_number.to_s
  end

  def container
    CONTAINER + 's'
  end

  def quantity_and_container
    quantity + ' ' + container
  end

  def action
    # Note the 'it' when count is 1, hence the pronoun function.
    "Take #{pronoun} down and pass it around,"
  end

  def pronoun
    'one'
  end
end

# BottleNumber0 class
class BottleNumber0 < BottleNumber
  def self.handles?(number)
    number.zero?
  end

  def action
    'Go to the store and buy some more,'
  end

  def quantity
    'no more'
  end

  def successor
    # new(99)
    BottleNumber.new(99)
  end
end

# BottleNumber1 class
class BottleNumber1 < BottleNumber
  def self.handles?(number)
    number == 1
  end

  def pronoun
    'it'
  end

  def container
    CONTAINER
  end
end

# BottleNumber6 class
class BottleNumber6 < BottleNumber
  def self.handles?(number)
    # number == 6  # Removed the song doesn't have a six-pack option. 
    false
  end

  def quantity
    # 'no more'
    1.to_s
  end

  def container
    # CONTAINER
    'six-pack'
  end
end

# BottleVerse class
class BottleVerse
  def initialize(bottle_number)
    @bottle_number = bottle_number
    # @number = bottle_number
  end

  attr_accessor :number

  def self.lyrics(count)
    # new(BottleNumber.for(count)).lyrics
    new(count).lyrics
  end

  def to_s
    # bottle_number = for(number)
    bottle_number = BottleNumber.for(@bottle_number)
    # bottle_number = BottleNumber.for(@number)

    "#{bottle_number} ".capitalize + "of #{BEV_PLUS_STORAGE}, #{bottle_number} of #{BEVERAGE}.\n"\
      "#{bottle_number.action} #{bottle_number.successor} of #{BEV_PLUS_STORAGE}.\n"
  end

  alias lyrics to_s
end

class BeerSong < CountdownSong
  def self.recite(first, number)
    BeerSong.new(verse_template: BottleVerse, max: first, min: 0 ).verses(first, first+1-number)
  end
end

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