Net.tutorialplus.com -Rspec tutorial- NoMethodError - ruby-on-rails

Question

I am following Rspec testing tutorial on Net.Tutsplus.com.
I've found problem I couldn't solve. Here the thing.
When I run test:
C:\projekt>rspec spec/library_spec.rb --format nested
I get:
C:/projekt/spec/library_spec.rb:35:in `block (3 levels) in <top (required)>': un
defined method `books' for nil:NilClass (NoMethodError)
library_spec.rb looks like that:
require "spec_helper"
describe "Library Object" do
before :all do
lib_arr = [
Book.new("JavaScript: The Good Parts", "Douglas Crockford", :development),
Book.new("Designing with Web Standarts", "Jeffrey Zeldman", :design),
Book.new("Don't Make me Think", "Steve Krug", :usability),
Book.new("JavaScript Patterns", "Stoyan Sefanov", :development),
Book.new("Responsive Web Design", "Ethan Marcotte", :design)
]
File.open "books.yml", "w" do |f|
f.write YAML::dump lib_arr
end
end
before :each do
#lib = Library.new "books.yml"
end
describe "#new" do
context "with no parameters" do
it "has no books" do
lib = Library.new
lib.books.length.should == 0
end
end
context "with a yaml file name parameters " do
it "has five books"
#lib.books.length.should == 5
end
end
end
Due to tutorial instructions I changed library.rb to:
require 'yaml'
class Library
attr_accessor :books
def initalize lib_file = false
#lib_file = lib_file
#books = #lib_file ? YAML::load(File.read(#lib_file)) : []
end
end
According to tutorial it should solve "books-NoMethodError" problem but it still apper.
Where is the problem?
Thanks for help!

Answer 1

undefined method books for nil:NilClass (NoMethodError) just means that you are calling a method books on something that is nil, in this case #lib.
You need to place the before(:each) hook that defines #lib inside a context or describe block, in your code it is not available in the describe '#new' block.
Also, you were missing a do after defining the it "has five books" spec.
I've corrected these errors below:
describe "#new" do
before :each do
#lib = Library.new "books.yml"
end
context "with no parameters" do
it "has no books" do
lib = Library.new
lib.books.length.should == 0
end
end
context "with a yaml file name parameters " do
it "has five books" do
#lib.books.length.should == 5
end
end
end