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ingemar's solution

to Beer Song in the Objective-C Track

Published at Jul 17 2019 · 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?

Setup

There are two different methods of getting set up to run the tests with Objective-C:

  • Create an Xcode project with a test target which will run the tests.
  • Use the ruby gem objc as a test runner utility.

Both are described in more detail here: http://exercism.io/languages/objective-c

Submitting Exercises

When submitting an exercise, make sure your solution file is in the same directory as the test code.

The submit command will look something like:

exercism submit <path-to-exercism-workspace>/objective-c/beer-song/BeerSong.m

You can find the Exercism workspace by running exercism debug and looking for the line beginning with Workspace.

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.

BeerSongTest.m

#import <XCTest/XCTest.h>

#if __has_include("BeerSongExample.h")
# import "BeerSongExample.h"
# else
# import "BeerSong.h"
#endif

@interface BeerSongTest : XCTestCase

@end

@implementation BeerSongTest

- (void)testVerseForZeroBeerBottles {
    
    BeerSongExample *songExample = [[BeerSongExample alloc]initWithNumberOfBeerBottles:0];
    NSString* expectedVerse = @"No more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall.";
    XCTAssertEqualObjects(expectedVerse, [songExample singBeerSong]);
    
}

-(void)testVersesForOneBeerBottle{
    BeerSongExample *songExample = [[BeerSongExample alloc]initWithNumberOfBeerBottles:1];
    NSString* expectedVerses = @"1 bottle of beer on the wall, 1 bottle of beer.\nTake one down and pass it around, no more bottles of beer on the wall.\n\nNo more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall."; //!OCLint
    XCTAssertEqualObjects(expectedVerses, [songExample singBeerSong]);
    
}

-(void)testVersesForTwoBeerBottles{
    
    BeerSongExample *songExample = [[BeerSongExample alloc]initWithNumberOfBeerBottles:2];
    NSString* expectedVerses = @"2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, 1 bottle of beer on the wall.\n\n1 bottle of beer on the wall, 1 bottle of beer.\nTake one down and pass it around, no more bottles of beer on the wall.\n\nNo more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall."; //!OCLint
    XCTAssertEqualObjects(expectedVerses, [songExample singBeerSong]);
}

-(void)testVersesForSeventyFiveBeerBottles{
    
    BeerSongExample *songExample = [[BeerSongExample alloc]initWithNumberOfBeerBottles:75];
    NSString* expectedVerses = @"75 bottles of beer on the wall, 75 bottles of beer.\nTake one down and pass it around, 74 bottles of beer on the wall.\n\n74 bottles of beer on the wall, 74 bottles of beer.\nTake one down and pass it around, 73 bottles of beer on the wall.\n\n73 bottles of beer on the wall, 73 bottles of beer.\nTake one down and pass it around, 72 bottles of beer on the wall.\n\n72 bottles of beer on the wall, 72 bottles of beer.\nTake one down and pass it around, 71 bottles of beer on the wall.\n\n71 bottles of beer on the wall, 71 bottles of beer.\nTake one down and pass it around, 70 bottles of beer on the wall.\n\n70 bottles of beer on the wall, 70 bottles of beer.\nTake one down and pass it around, 69 bottles of beer on the wall.\n\n69 bottles of beer on the wall, 69 bottles of beer.\nTake one down and pass it around, 68 bottles of beer on the wall.\n\n68 bottles of beer on the wall, 68 bottles of beer.\nTake one down and pass it around, 67 bottles of beer on the wall.\n\n67 bottles of beer on the wall, 67 bottles of beer.\nTake one down and pass it around, 66 bottles of beer on the wall.\n\n66 bottles of beer on the wall, 66 bottles of beer.\nTake one down and pass it around, 65 bottles of beer on the wall.\n\n65 bottles of beer on the wall, 65 bottles of beer.\nTake one down and pass it around, 64 bottles of beer on the wall.\n\n64 bottles of beer on the wall, 64 bottles of beer.\nTake one down and pass it around, 63 bottles of beer on the wall.\n\n63 bottles of beer on the wall, 63 bottles of beer.\nTake one down and pass it around, 62 bottles of beer on the wall.\n\n62 bottles of beer on the wall, 62 bottles of beer.\nTake one down and pass it around, 61 bottles of beer on the wall.\n\n61 bottles of beer on the wall, 61 bottles of beer.\nTake one down and pass it around, 60 bottles of beer on the wall.\n\n60 bottles of beer on the wall, 60 bottles of beer.\nTake one down and pass it around, 59 bottles of beer on the wall.\n\n59 bottles of beer on the wall, 59 bottles of beer.\nTake one down and pass it around, 58 bottles of beer on the wall.\n\n58 bottles of beer on the wall, 58 bottles of beer.\nTake one down and pass it around, 57 bottles of beer on the wall.\n\n57 bottles of beer on the wall, 57 bottles of beer.\nTake one down and pass it around, 56 bottles of beer on the wall.\n\n56 bottles of beer on the wall, 56 bottles of beer.\nTake one down and pass it around, 55 bottles of beer on the wall.\n\n55 bottles of beer on the wall, 55 bottles of beer.\nTake one down and pass it around, 54 bottles of beer on the wall.\n\n54 bottles of beer on the wall, 54 bottles of beer.\nTake one down and pass it around, 53 bottles of beer on the wall.\n\n53 bottles of beer on the wall, 53 bottles of beer.\nTake one down and pass it around, 52 bottles of beer on the wall.\n\n52 bottles of beer on the wall, 52 bottles of beer.\nTake one down and pass it around, 51 bottles of beer on the wall.\n\n51 bottles of beer on the wall, 51 bottles of beer.\nTake one down and pass it around, 50 bottles of beer on the wall.\n\n50 bottles of beer on the wall, 50 bottles of beer.\nTake one down and pass it around, 49 bottles of beer on the wall.\n\n49 bottles of beer on the wall, 49 bottles of beer.\nTake one down and pass it around, 48 bottles of beer on the wall.\n\n48 bottles of beer on the wall, 48 bottles of beer.\nTake one down and pass it around, 47 bottles of beer on the wall.\n\n47 bottles of beer on the wall, 47 bottles of beer.\nTake one down and pass it around, 46 bottles of beer on the wall.\n\n46 bottles of beer on the wall, 46 bottles of beer.\nTake one down and pass it around, 45 bottles of beer on the wall.\n\n45 bottles of beer on the wall, 45 bottles of beer.\nTake one down and pass it around, 44 bottles of beer on the wall.\n\n44 bottles of beer on the wall, 44 bottles of beer.\nTake one down and pass it around, 43 bottles of beer on the wall.\n\n43 bottles of beer on the wall, 43 bottles of beer.\nTake one down and pass it around, 42 bottles of beer on the wall.\n\n42 bottles of beer on the wall, 42 bottles of beer.\nTake one down and pass it around, 41 bottles of beer on the wall.\n\n41 bottles of beer on the wall, 41 bottles of beer.\nTake one down and pass it around, 40 bottles of beer on the wall.\n\n40 bottles of beer on the wall, 40 bottles of beer.\nTake one down and pass it around, 39 bottles of beer on the wall.\n\n39 bottles of beer on the wall, 39 bottles of beer.\nTake one down and pass it around, 38 bottles of beer on the wall.\n\n38 bottles of beer on the wall, 38 bottles of beer.\nTake one down and pass it around, 37 bottles of beer on the wall.\n\n37 bottles of beer on the wall, 37 bottles of beer.\nTake one down and pass it around, 36 bottles of beer on the wall.\n\n36 bottles of beer on the wall, 36 bottles of beer.\nTake one down and pass it around, 35 bottles of beer on the wall.\n\n35 bottles of beer on the wall, 35 bottles of beer.\nTake one down and pass it around, 34 bottles of beer on the wall.\n\n34 bottles of beer on the wall, 34 bottles of beer.\nTake one down and pass it around, 33 bottles of beer on the wall.\n\n33 bottles of beer on the wall, 33 bottles of beer.\nTake one down and pass it around, 32 bottles of beer on the wall.\n\n32 bottles of beer on the wall, 32 bottles of beer.\nTake one down and pass it around, 31 bottles of beer on the wall.\n\n31 bottles of beer on the wall, 31 bottles of beer.\nTake one down and pass it around, 30 bottles of beer on the wall.\n\n30 bottles of beer on the wall, 30 bottles of beer.\nTake one down and pass it around, 29 bottles of beer on the wall.\n\n29 bottles of beer on the wall, 29 bottles of beer.\nTake one down and pass it around, 28 bottles of beer on the wall.\n\n28 bottles of beer on the wall, 28 bottles of beer.\nTake one down and pass it around, 27 bottles of beer on the wall.\n\n27 bottles of beer on the wall, 27 bottles of beer.\nTake one down and pass it around, 26 bottles of beer on the wall.\n\n26 bottles of beer on the wall, 26 bottles of beer.\nTake one down and pass it around, 25 bottles of beer on the wall.\n\n25 bottles of beer on the wall, 25 bottles of beer.\nTake one down and pass it around, 24 bottles of beer on the wall.\n\n24 bottles of beer on the wall, 24 bottles of beer.\nTake one down and pass it around, 23 bottles of beer on the wall.\n\n23 bottles of beer on the wall, 23 bottles of beer.\nTake one down and pass it around, 22 bottles of beer on the wall.\n\n22 bottles of beer on the wall, 22 bottles of beer.\nTake one down and pass it around, 21 bottles of beer on the wall.\n\n21 bottles of beer on the wall, 21 bottles of beer.\nTake one down and pass it around, 20 bottles of beer on the wall.\n\n20 bottles of beer on the wall, 20 bottles of beer.\nTake one down and pass it around, 19 bottles of beer on the wall.\n\n19 bottles of beer on the wall, 19 bottles of beer.\nTake one down and pass it around, 18 bottles of beer on the wall.\n\n18 bottles of beer on the wall, 18 bottles of beer.\nTake one down and pass it around, 17 bottles of beer on the wall.\n\n17 bottles of beer on the wall, 17 bottles of beer.\nTake one down and pass it around, 16 bottles of beer on the wall.\n\n16 bottles of beer on the wall, 16 bottles of beer.\nTake one down and pass it around, 15 bottles of beer on the wall.\n\n15 bottles of beer on the wall, 15 bottles of beer.\nTake one down and pass it around, 14 bottles of beer on the wall.\n\n14 bottles of beer on the wall, 14 bottles of beer.\nTake one down and pass it around, 13 bottles of beer on the wall.\n\n13 bottles of beer on the wall, 13 bottles of beer.\nTake one down and pass it around, 12 bottles of beer on the wall.\n\n12 bottles of beer on the wall, 12 bottles of beer.\nTake one down and pass it around, 11 bottles of beer on the wall.\n\n11 bottles of beer on the wall, 11 bottles of beer.\nTake one down and pass it around, 10 bottles of beer on the wall.\n\n10 bottles of beer on the wall, 10 bottles of beer.\nTake one down and pass it around, 9 bottles of beer on the wall.\n\n9 bottles of beer on the wall, 9 bottles of beer.\nTake one down and pass it around, 8 bottles of beer on the wall.\n\n8 bottles of beer on the wall, 8 bottles of beer.\nTake one down and pass it around, 7 bottles of beer on the wall.\n\n7 bottles of beer on the wall, 7 bottles of beer.\nTake one down and pass it around, 6 bottles of beer on the wall.\n\n6 bottles of beer on the wall, 6 bottles of beer.\nTake one down and pass it around, 5 bottles of beer on the wall.\n\n5 bottles of beer on the wall, 5 bottles of beer.\nTake one down and pass it around, 4 bottles of beer on the wall.\n\n4 bottles of beer on the wall, 4 bottles of beer.\nTake one down and pass it around, 3 bottles of beer on the wall.\n\n3 bottles of beer on the wall, 3 bottles of beer.\nTake one down and pass it around, 2 bottles of beer on the wall.\n\n2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, 1 bottle of beer on the wall.\n\n1 bottle of beer on the wall, 1 bottle of beer.\nTake one down and pass it around, no more bottles of beer on the wall.\n\nNo more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall."; //!OCLint
    XCTAssertEqualObjects(expectedVerses, [songExample singBeerSong]);
}

-(void)testAllVersesOfBeerSong{
    
    BeerSongExample *songExample = [[BeerSongExample alloc]initWithNumberOfBeerBottles:99];
    NSString* expectedVerses = @"99 bottles of beer on the wall, 99 bottles of beer.\nTake one down and pass it around, 98 bottles of beer on the wall.\n\n98 bottles of beer on the wall, 98 bottles of beer.\nTake one down and pass it around, 97 bottles of beer on the wall.\n\n97 bottles of beer on the wall, 97 bottles of beer.\nTake one down and pass it around, 96 bottles of beer on the wall.\n\n96 bottles of beer on the wall, 96 bottles of beer.\nTake one down and pass it around, 95 bottles of beer on the wall.\n\n95 bottles of beer on the wall, 95 bottles of beer.\nTake one down and pass it around, 94 bottles of beer on the wall.\n\n94 bottles of beer on the wall, 94 bottles of beer.\nTake one down and pass it around, 93 bottles of beer on the wall.\n\n93 bottles of beer on the wall, 93 bottles of beer.\nTake one down and pass it around, 92 bottles of beer on the wall.\n\n92 bottles of beer on the wall, 92 bottles of beer.\nTake one down and pass it around, 91 bottles of beer on the wall.\n\n91 bottles of beer on the wall, 91 bottles of beer.\nTake one down and pass it around, 90 bottles of beer on the wall.\n\n90 bottles of beer on the wall, 90 bottles of beer.\nTake one down and pass it around, 89 bottles of beer on the wall.\n\n89 bottles of beer on the wall, 89 bottles of beer.\nTake one down and pass it around, 88 bottles of beer on the wall.\n\n88 bottles of beer on the wall, 88 bottles of beer.\nTake one down and pass it around, 87 bottles of beer on the wall.\n\n87 bottles of beer on the wall, 87 bottles of beer.\nTake one down and pass it around, 86 bottles of beer on the wall.\n\n86 bottles of beer on the wall, 86 bottles of beer.\nTake one down and pass it around, 85 bottles of beer on the wall.\n\n85 bottles of beer on the wall, 85 bottles of beer.\nTake one down and pass it around, 84 bottles of beer on the wall.\n\n84 bottles of beer on the wall, 84 bottles of beer.\nTake one down and pass it around, 83 bottles of beer on the wall.\n\n83 bottles of beer on the wall, 83 bottles of beer.\nTake one down and pass it around, 82 bottles of beer on the wall.\n\n82 bottles of beer on the wall, 82 bottles of beer.\nTake one down and pass it around, 81 bottles of beer on the wall.\n\n81 bottles of beer on the wall, 81 bottles of beer.\nTake one down and pass it around, 80 bottles of beer on the wall.\n\n80 bottles of beer on the wall, 80 bottles of beer.\nTake one down and pass it around, 79 bottles of beer on the wall.\n\n79 bottles of beer on the wall, 79 bottles of beer.\nTake one down and pass it around, 78 bottles of beer on the wall.\n\n78 bottles of beer on the wall, 78 bottles of beer.\nTake one down and pass it around, 77 bottles of beer on the wall.\n\n77 bottles of beer on the wall, 77 bottles of beer.\nTake one down and pass it around, 76 bottles of beer on the wall.\n\n76 bottles of beer on the wall, 76 bottles of beer.\nTake one down and pass it around, 75 bottles of beer on the wall.\n\n75 bottles of beer on the wall, 75 bottles of beer.\nTake one down and pass it around, 74 bottles of beer on the wall.\n\n74 bottles of beer on the wall, 74 bottles of beer.\nTake one down and pass it around, 73 bottles of beer on the wall.\n\n73 bottles of beer on the wall, 73 bottles of beer.\nTake one down and pass it around, 72 bottles of beer on the wall.\n\n72 bottles of beer on the wall, 72 bottles of beer.\nTake one down and pass it around, 71 bottles of beer on the wall.\n\n71 bottles of beer on the wall, 71 bottles of beer.\nTake one down and pass it around, 70 bottles of beer on the wall.\n\n70 bottles of beer on the wall, 70 bottles of beer.\nTake one down and pass it around, 69 bottles of beer on the wall.\n\n69 bottles of beer on the wall, 69 bottles of beer.\nTake one down and pass it around, 68 bottles of beer on the wall.\n\n68 bottles of beer on the wall, 68 bottles of beer.\nTake one down and pass it around, 67 bottles of beer on the wall.\n\n67 bottles of beer on the wall, 67 bottles of beer.\nTake one down and pass it around, 66 bottles of beer on the wall.\n\n66 bottles of beer on the wall, 66 bottles of beer.\nTake one down and pass it around, 65 bottles of beer on the wall.\n\n65 bottles of beer on the wall, 65 bottles of beer.\nTake one down and pass it around, 64 bottles of beer on the wall.\n\n64 bottles of beer on the wall, 64 bottles of beer.\nTake one down and pass it around, 63 bottles of beer on the wall.\n\n63 bottles of beer on the wall, 63 bottles of beer.\nTake one down and pass it around, 62 bottles of beer on the wall.\n\n62 bottles of beer on the wall, 62 bottles of beer.\nTake one down and pass it around, 61 bottles of beer on the wall.\n\n61 bottles of beer on the wall, 61 bottles of beer.\nTake one down and pass it around, 60 bottles of beer on the wall.\n\n60 bottles of beer on the wall, 60 bottles of beer.\nTake one down and pass it around, 59 bottles of beer on the wall.\n\n59 bottles of beer on the wall, 59 bottles of beer.\nTake one down and pass it around, 58 bottles of beer on the wall.\n\n58 bottles of beer on the wall, 58 bottles of beer.\nTake one down and pass it around, 57 bottles of beer on the wall.\n\n57 bottles of beer on the wall, 57 bottles of beer.\nTake one down and pass it around, 56 bottles of beer on the wall.\n\n56 bottles of beer on the wall, 56 bottles of beer.\nTake one down and pass it around, 55 bottles of beer on the wall.\n\n55 bottles of beer on the wall, 55 bottles of beer.\nTake one down and pass it around, 54 bottles of beer on the wall.\n\n54 bottles of beer on the wall, 54 bottles of beer.\nTake one down and pass it around, 53 bottles of beer on the wall.\n\n53 bottles of beer on the wall, 53 bottles of beer.\nTake one down and pass it around, 52 bottles of beer on the wall.\n\n52 bottles of beer on the wall, 52 bottles of beer.\nTake one down and pass it around, 51 bottles of beer on the wall.\n\n51 bottles of beer on the wall, 51 bottles of beer.\nTake one down and pass it around, 50 bottles of beer on the wall.\n\n50 bottles of beer on the wall, 50 bottles of beer.\nTake one down and pass it around, 49 bottles of beer on the wall.\n\n49 bottles of beer on the wall, 49 bottles of beer.\nTake one down and pass it around, 48 bottles of beer on the wall.\n\n48 bottles of beer on the wall, 48 bottles of beer.\nTake one down and pass it around, 47 bottles of beer on the wall.\n\n47 bottles of beer on the wall, 47 bottles of beer.\nTake one down and pass it around, 46 bottles of beer on the wall.\n\n46 bottles of beer on the wall, 46 bottles of beer.\nTake one down and pass it around, 45 bottles of beer on the wall.\n\n45 bottles of beer on the wall, 45 bottles of beer.\nTake one down and pass it around, 44 bottles of beer on the wall.\n\n44 bottles of beer on the wall, 44 bottles of beer.\nTake one down and pass it around, 43 bottles of beer on the wall.\n\n43 bottles of beer on the wall, 43 bottles of beer.\nTake one down and pass it around, 42 bottles of beer on the wall.\n\n42 bottles of beer on the wall, 42 bottles of beer.\nTake one down and pass it around, 41 bottles of beer on the wall.\n\n41 bottles of beer on the wall, 41 bottles of beer.\nTake one down and pass it around, 40 bottles of beer on the wall.\n\n40 bottles of beer on the wall, 40 bottles of beer.\nTake one down and pass it around, 39 bottles of beer on the wall.\n\n39 bottles of beer on the wall, 39 bottles of beer.\nTake one down and pass it around, 38 bottles of beer on the wall.\n\n38 bottles of beer on the wall, 38 bottles of beer.\nTake one down and pass it around, 37 bottles of beer on the wall.\n\n37 bottles of beer on the wall, 37 bottles of beer.\nTake one down and pass it around, 36 bottles of beer on the wall.\n\n36 bottles of beer on the wall, 36 bottles of beer.\nTake one down and pass it around, 35 bottles of beer on the wall.\n\n35 bottles of beer on the wall, 35 bottles of beer.\nTake one down and pass it around, 34 bottles of beer on the wall.\n\n34 bottles of beer on the wall, 34 bottles of beer.\nTake one down and pass it around, 33 bottles of beer on the wall.\n\n33 bottles of beer on the wall, 33 bottles of beer.\nTake one down and pass it around, 32 bottles of beer on the wall.\n\n32 bottles of beer on the wall, 32 bottles of beer.\nTake one down and pass it around, 31 bottles of beer on the wall.\n\n31 bottles of beer on the wall, 31 bottles of beer.\nTake one down and pass it around, 30 bottles of beer on the wall.\n\n30 bottles of beer on the wall, 30 bottles of beer.\nTake one down and pass it around, 29 bottles of beer on the wall.\n\n29 bottles of beer on the wall, 29 bottles of beer.\nTake one down and pass it around, 28 bottles of beer on the wall.\n\n28 bottles of beer on the wall, 28 bottles of beer.\nTake one down and pass it around, 27 bottles of beer on the wall.\n\n27 bottles of beer on the wall, 27 bottles of beer.\nTake one down and pass it around, 26 bottles of beer on the wall.\n\n26 bottles of beer on the wall, 26 bottles of beer.\nTake one down and pass it around, 25 bottles of beer on the wall.\n\n25 bottles of beer on the wall, 25 bottles of beer.\nTake one down and pass it around, 24 bottles of beer on the wall.\n\n24 bottles of beer on the wall, 24 bottles of beer.\nTake one down and pass it around, 23 bottles of beer on the wall.\n\n23 bottles of beer on the wall, 23 bottles of beer.\nTake one down and pass it around, 22 bottles of beer on the wall.\n\n22 bottles of beer on the wall, 22 bottles of beer.\nTake one down and pass it around, 21 bottles of beer on the wall.\n\n21 bottles of beer on the wall, 21 bottles of beer.\nTake one down and pass it around, 20 bottles of beer on the wall.\n\n20 bottles of beer on the wall, 20 bottles of beer.\nTake one down and pass it around, 19 bottles of beer on the wall.\n\n19 bottles of beer on the wall, 19 bottles of beer.\nTake one down and pass it around, 18 bottles of beer on the wall.\n\n18 bottles of beer on the wall, 18 bottles of beer.\nTake one down and pass it around, 17 bottles of beer on the wall.\n\n17 bottles of beer on the wall, 17 bottles of beer.\nTake one down and pass it around, 16 bottles of beer on the wall.\n\n16 bottles of beer on the wall, 16 bottles of beer.\nTake one down and pass it around, 15 bottles of beer on the wall.\n\n15 bottles of beer on the wall, 15 bottles of beer.\nTake one down and pass it around, 14 bottles of beer on the wall.\n\n14 bottles of beer on the wall, 14 bottles of beer.\nTake one down and pass it around, 13 bottles of beer on the wall.\n\n13 bottles of beer on the wall, 13 bottles of beer.\nTake one down and pass it around, 12 bottles of beer on the wall.\n\n12 bottles of beer on the wall, 12 bottles of beer.\nTake one down and pass it around, 11 bottles of beer on the wall.\n\n11 bottles of beer on the wall, 11 bottles of beer.\nTake one down and pass it around, 10 bottles of beer on the wall.\n\n10 bottles of beer on the wall, 10 bottles of beer.\nTake one down and pass it around, 9 bottles of beer on the wall.\n\n9 bottles of beer on the wall, 9 bottles of beer.\nTake one down and pass it around, 8 bottles of beer on the wall.\n\n8 bottles of beer on the wall, 8 bottles of beer.\nTake one down and pass it around, 7 bottles of beer on the wall.\n\n7 bottles of beer on the wall, 7 bottles of beer.\nTake one down and pass it around, 6 bottles of beer on the wall.\n\n6 bottles of beer on the wall, 6 bottles of beer.\nTake one down and pass it around, 5 bottles of beer on the wall.\n\n5 bottles of beer on the wall, 5 bottles of beer.\nTake one down and pass it around, 4 bottles of beer on the wall.\n\n4 bottles of beer on the wall, 4 bottles of beer.\nTake one down and pass it around, 3 bottles of beer on the wall.\n\n3 bottles of beer on the wall, 3 bottles of beer.\nTake one down and pass it around, 2 bottles of beer on the wall.\n\n2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, 1 bottle of beer on the wall.\n\n1 bottle of beer on the wall, 1 bottle of beer.\nTake one down and pass it around, no more bottles of beer on the wall.\n\nNo more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall."; //!OCLint
    XCTAssertEqualObjects(expectedVerses, [songExample singBeerSong]);
}

@end

beer-song-tests/BeerSong.h

//
//  BeerSong.h
//  beer-song-tests
//
//  Created by Ingemar Pertl on 16.07.19.
//  Copyright © 2019 Ingemar Pertl. All rights reserved.
//

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

@interface BeerSongExample : NSObject

-(instancetype)initWithNumberOfBeerBottles:(int)number;

-(NSString*)singBeerSong;

@end

NS_ASSUME_NONNULL_END

beer-song-tests/BeerSong.m

//
//  BeerSong.m
//  beer-song-tests
//
//  Created by Ingemar Pertl on 16.07.19.
//  Copyright © 2019 Ingemar Pertl. All rights reserved.
//

#import "BeerSong.h"

@implementation BeerSongExample {
    int numberOfBeerBottles;
}

-(instancetype)initWithNumberOfBeerBottles:(int)number {
    self = [super init];

    numberOfBeerBottles = number;
    
    return self;
}

-(NSString*)singBeerSong {
    NSString *beerSong = [NSString new];
    int counter = numberOfBeerBottles;
    
    while(counter > 0) {
        if(counter < numberOfBeerBottles)
            beerSong = [beerSong stringByAppendingString:@"\n"];
        
        if(counter == 1)
            beerSong = [beerSong stringByAppendingString:@"1 bottle of beer on the wall, 1 bottle of beer.\n"];
        else
            beerSong = [beerSong stringByAppendingFormat:@"%i bottles of beer on the wall, %i bottles of beer.\n", counter, counter];
        
        counter--;
        
        NSString *bottlesCountTemplate = [NSString stringWithFormat:@"%i bottles of beer on the wall.\n", counter];
        
        if(counter == 0)
            bottlesCountTemplate = @"no more bottles of beer on the wall.\n\n";
        else if(counter == 1)
            bottlesCountTemplate = @"1 bottle of beer on the wall.\n";
        
        beerSong = [beerSong stringByAppendingFormat:@"Take one down and pass it around, %@", bottlesCountTemplate];
    }
    
    beerSong = [beerSong stringByAppendingFormat:@"No more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall."];
    
    return beerSong;
}

@end

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