SessionsController中的NoMethodError #create

Question

我一直在关注Michael Hartl的教程，对于那些熟悉它的人，我正在阅读第10课 - 更新用户。

到目前为止，我已经构建了一个应该允许用户注册，登录和注销的应用。我的应用允许用户注册，但在尝试登录时，我收到以下错误：

SessionsController中的NoMethodError #create

undefined method `-' for nil:NilClass

Rails.root: /Users/user/Sites/rails_projects/sample_app1

app/controllers/sessions_controller.rb:11:in `create'

请求

参数：

{"utf8"=>"✓",
"authenticity_token"=>"/SEaqnrMf5X0pd4FVWbu8uWVAjTNw4LPKiXg+8Hl0PQ=",
"session"=>{"email"=>"Anthonypane@example.com",
"password"=>"[FILTERED]"},
"commit"=>"Sign in"} 

这是我的Session_Controller内容：

class SessionsController < ApplicationController
def new
@title = "Sign in"
end

def create
user = User.authenticate(params[:session][:email],
                        params[:session][:password])
if user.nil?
flash.now[:error] = "Invalid email/password combination."
@title - "Sign In"
render 'new'
else
sign_in user
redirect_to user
end
end   

def destroy
 sign_out
 redirect_to root_path
end
end

Users_Controller内容

class UsersController < ApplicationController

def show
 @user = User.find(params[:id])
 @title = @user.name 
 end

def new
@user = User.new
@title = "Sign up"
end

def create
@user = User.new(params[:user])
if @user.save
sign_in @user
redirect_to @user, :flash =>  {:success => "Welcome to the Fun House!"}
else
@title = "Sign up"
 render 'new'
end
end
end

Sessions_helper内容

module SessionsHelper

 def sign_in(user)
cookies.permanent.signed[:remember_token] = [user.id, user.salt]
current_user = user
end

def current_user=(user)
@current_user = user
end

def current_user
 @current_user ||= user_from_remember_token
end

def signed_in?
 !current_user.nil? 
end

def sign_out
 cookies.delete(:remember_token)
 self.current_user = nil
end 

private

def user_from_remember_token
 User.authenticate_with_salt(*remember_token)
end

def remember_token
 cookies.signed[:remember_token] || [nil, nil]
end

end

最后Users_helper内容：

module UsersHelper
def gravatar_for(user, options = { :size => 50})
gravatar_image_tag(user.email.downcase, :alt => user.name, 
                                        :class => 'gravatar',
                                        :gravatar => options)
end
end

Answer 1

:-)感谢Taryn East解决了问题。

def has_password?(submitted_password)
  encrypted_password == encrypted(submitted_password)
end

应该是

def has_password?(submitted_password)
  encrypted_password == encrypt(submitted_password)
end

Answer 2

问题是，与例外情况一样，您的行@title - "Sign In"：它应该是
@title = "Sign In"。

但是，我会说更大的问题是，当Rails 3.0 version是最新版本时，您现在正在执行教程的Rails 3.2 version。这绝对值得转换。