无法加载活动记录？答案

【问题标题】：Cannot load active record?无法加载活动记录？
【发布时间】：2015-02-19 17:18:50
【问题描述】：

我有一个 gem，我正在尝试在其中测试一些 mixins，这些 mixins 将在模型中用于确定关系并添加辅助函数，我遇到的问题是当我在我的 gem 中测试这些 mixins我得到：uninitialized constant ActiveRecord (NameError)。

在我的rails_helper.rb（rspec 3.1）中，我添加了以下内容：

ActiveRecord::Base.establish_connection(:adapter => 'sqlite3')
load(File.dirname(__FILE__) + "/schema.rb")

然后在我的spec/models/user.rb 中添加：

describe "Test the user model mixin" do

  class User < ActiveRecord::Base
     # This is what I am testing
    include CoreModels::Models::User
  end

  context "Fail to find a user" do
    it "should return nil on a user not existing" do
      User.find_by_first_name('sally').should == nil
    end
  end
end

当我运行时：

$ bin/rspec
/Users/Adam/Documents/Rails-Projects/core_models/spec/models/user_spec.rb:4:in `block in <top (required)>': uninitialized constant ActiveRecord (NameError)
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/example_group.rb:325:in `module_exec'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/example_group.rb:325:in `subclass'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/example_group.rb:219:in `block in define_example_group_method'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/dsl.rb:41:in `block in expose_example_group_alias'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/dsl.rb:79:in `block (2 levels) in expose_example_group_alias_globally'
    from /Users/Adam/Documents/Rails-Projects/core_models/spec/models/user_spec.rb:2:in `<top (required)>'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/configuration.rb:1105:in `load'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/configuration.rb:1105:in `block in load_spec_files'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/configuration.rb:1105:in `each'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/configuration.rb:1105:in `load_spec_files'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/runner.rb:96:in `setup'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/runner.rb:84:in `run'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/runner.rb:69:in `run'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/lib/rspec/core/runner.rb:37:in `invoke'
    from /Users/Adam/Documents/Rails-Projects/core_models/.bundle/gems/gems/rspec-core-3.1.7/exe/rspec:4:in `<top (required)>'
    from bin/rspec:16:in `load'
    from bin/rspec:16:in `<main>'

我需要主动记录吗？

【问题讨论】：

标签： ruby-on-rails ruby activerecord rspec

【解决方案1】：

确保您在 spec/rails_helper.rb 中加载 Rails 环境：

ENV["RAILS_ENV"] ||= 'test'
require 'spec_helper'
require File.expand_path("../../config/environment", __FILE__) # LOADS Rails env
require 'rspec/rails'

如果您想查看干净的spec/rails_helper.rb，请使用提供的生成器重新创建rails_helper 文件：rails generate rspec:install。

【讨论】：