ruby - Rails——before_save 不工作？

Question

我正在学习 Michael Hartl 的 RoR 教程，它涵盖了密码加密的基础知识。这是当前的用户模型:

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

(显然这没有进行任何加密，因为加密方法并未真正实现，但这不是我的问题)

然后我写了下面的规范(根据教程):

require 'spec_helper'

describe User do

    before(:each) do
        @attr = { :name => "Example User", :email => "user@example.com",
                  :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

这些测试中的第一个通过，但由于 @user.encrypted_pa​​ssword 为 nil，因此第二个测试失败。但我不明白为什么它是 nil，因为 encrypt_password 方法应该由 before_save 调用。我知道我一定遗漏了什么 - 有人可以解释一下吗？

Answer 1

encrypt_password 方法不正确，应该是:

def encrypt_password
  self.encrypted_password = encrypt(password)
end

注意 self 的使用，它将正确设置用户对象的属性，而不是创建一个被遗忘的实例变量。