Pickaxe code error

Ruby
1

Not sure what’s going on with some code in Programming Ruby, it’s
early on where a SongList container is being created and test units
are run.
I’m receiving this error:

  1. Error:
    test_delete(TestSongList):
    NameError: uninitialized constant TestSongList::Song
    pickaxe_SongListContainer.rb:52:in `test_delete’

the rb:52 won’t be right as I’ve put notes in comments between the
code, which I’m stripping here. Perhaps someone is familiar with
example. I checked errata with no luck…TIA

require ‘test/unit’

class SongList
def initialize
@songs = Array.new
end

def append(song)
#songs.push(song)
self
end

def delete_first
@songs.shift
end

def delete_last
@songs.pop
end

def
@songs[index]
end
end

class TestSongList < Test::Unit::TestCase
def test_delete
list = SongList.new
s1 = Song.new(‘title1’, ‘artist1’, 1)
s2 = Song.new(‘title2’, ‘artist2’, 2)
s3 = Song.new(‘title3’, ‘artist3’, 3)
s4 = Song.new(‘title4’, ‘artist4’, 4)

list.append(s1).append(s2).append(s3).append(s4)

assert_equal(s1, list[0])
assert_equal(s3, list[2])
assert_nil(list[9])

assert_equal(s1,  list.delete_first)
assert_equal(s2,  list.delete_first)
assert_equal(s4,  list.delete_last)
assert_equal(s3,  list.delete_last)
assert_nil(list.delete_last)

end
end

2

Just realized that this needed to be in with the rest of the previous
jukebox code.
Sorry - ignore.

Stuart

3

Back again on this one, still getting a test delete failure.

  1. Failure:
    test_delete(TestSongList) [pickaxe_p23.rb:137]:
    <#<Song:0x28a2d58 @artist=“artist1”, @duration=1, @name=“title1”>>
    expected but was
    .

Not sure what this means exactly?

Anyone else have this issue or remember the section of the book ?

Stuart

1 tests, 1 assertions, 1 failures, 0 errors

4

stuart fellowes wrote:

Back again on this one, still getting a test delete failure.

  1. Failure:
    test_delete(TestSongList) [pickaxe_p23.rb:137]:
    <#<Song:0x28a2d58 @artist=“artist1”, @duration=1, @name=“title1”>>
    expected but was
    .

Not sure what this means exactly?

Anyone else have this issue or remember the section of the book ?

Stuart

1 tests, 1 assertions, 1 failures, 0 errors

you have the following:
def append(song)
#songs.push(song)
self
end

Note that the line to push the song onto the list is commented out.
Looks like you hit # instead of @

cheers

5

Yep, that was the error! Thank you…much obliged!

Stuart