Rails -- before_save not working?

Question

I am following Michael Hartl's RoR tutorial, and it is covering the basics of password encryption. This is the User model as it currently stands:

class User < ActiveRecord::Base
    attr_accessor :password

    attr_accessible :name, :email,: password, :password_confirmation

    email_regex = /^[A-Za-z0-9._+-]+@[A-Za-z0-9._-]+\.[A-Za-z0-9._-]+[A-Za-z]$/
                                              #tests for valid email addresses.

    validates :name, :presence => true,
                     :length => {:maximum => 50}
    validates :email, :presence => true,
                      :format => {:with => email_regex},
                      :uniqueness => {:case_sensitive => false}
    validates :password, :presence => true,
                         :length => {:maximum => 20, :minimum => 6},
                         :confirmation => true

    before_save :encrypt_password

    private

        def encrypt_password
            @encrypted_password = encrypt(password)
        end

        def encrypt(string)
            string
        end
end

(Obviously this isn't doing any encrypting because the encrypt method isn't really implemented but that's not my question)

I then wrote the following Spec (according to the tutorial):

require 'spec_helper'

describe User do

    before(:each) do
        @attr = { :name => "Example User", :email => "[email protected]",
                  :password => "abc123", :password_confirmation => "abc123"}
    end

    describe "password encryption" do

        before(:each) do
            @user = User.create!(@attr) # we are going to need a valid user in order
                                        # for these tests to run.
        end

        it "should have an encrypted password attribute" do
            @user.should respond_to(:encrypted_password)
        end

        it "should set the encrypted password upon user creation" do
            @user.encrypted_password.should_not be_blank
        end

    end
end

The first of these tests passes, but since @user.encrypted_password is nil, the second test fails. But I don't understand why it's nil since the encrypt_password method should be being called by before_save. I know I must be missing something -- can someone please explain?

Answer 1

The encrypt_password method is incorrect, it should read:

def encrypt_password
  self.encrypted_password = encrypt(password)
end

Note the use of self, which will properly set the attribute for the user object rather than creating an instance variable which is forgotten.