From: Dark Ambient <sambient@...>
Date: 2006-07-05T20:37:59+09:00
Subject: Re: Pickaxe code error

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

Stuart

On 7/5/06, Dark Ambient <sambient@gmail.com> wrote:
> 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 [](index)
>     @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
>
>