No method error - save from rubystutorial.org

Question

I've been following along Hartl's book at rubystutorial.org and stuck on this error

When I run rspec tests it tells me that the method (save) does not exist for user

Here's my code and test. I can't find what's wrong with it and why the method doesn't exist within @user

user_spec.rb

require 'spec_helper'

describe User do

  before do
    @user = User.new(name: "Example User", email: "[email protected]") 
  end

  subject { @user }

  it { should respond_to(:name) }
  it { should respond_to(:email) }

  it { should be_valid }

  describe "when name is not present" do
    before { @user.name = " " }
    it { should_not be_valid }
  end

  describe "when email is not present" do
    before { @user.email = " " }
    it { should_not be_valid }
  end

  describe "when name is too long" do
    before { @user.name = "a" * 51 }
    it { should_not be_valid } 
  end

  describe "when email format is invalid" do
    it "shoud be invalid" do 
      addresses = %w[user@foo,com user_at_foo.org example.user@foo. foo@bar_baz.com foo@bar+baz.com]
      addresses.each do |invalid_address|
        @user.email = invalid_address
        expect(@user).not_to be_valid
      end
    end
  end

  describe "when email format is valid" do 
    it "should be valid" do 
      addresses = %w[[email protected] [email protected] [email protected] [email protected]]
      addresses.each do |valid_address|
        @user.email = valid_address
        expect(@user).to be_valid
      end
    end
  end

  describe "when email address is already taken" do 
    before do
      user_with_same_email = @user.dup
      user_with_same_email = @user.email.upcase
      user_with_same_email.save
    end

    it { should_not be_valid }
  end

end

And my user.rb

class User < ActiveRecord::Base
    before_save { self.email = email.downcase }
    validates(:name, presence: true, length: { maximum: 50 } )
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
    validates(:email, presence: true, format: { with: VALID_EMAIL_REGEX },
                      uniqueness: { case_sensitive: false } )
end

Exact error is

Failures:

1) User when email address is already taken 

 Failure/Error: user_with_same_email.save
 NoMethodError:
   undefined method `save' for "[email protected]":String
 # ./spec/models/user_spec.rb:55:in `block (3 levels) in <top (required)>'

Finished in 0.411 seconds
24 examples, 1 failure

Failed examples:

rspec ./spec/models/user_spec.rb:58 # User when email address is already take

Answer 1

You are defining a user and then change it on string (email, so email has no save method) in the next lines:

user_with_same_email = @user.dup
user_with_same_email = @user.email.upcase
user_with_same_email.save

You should change it for this:

user_with_same_email = @user.dup
user_with_same_email.email = @user.email.upcase
user_with_same_email.save