ruby-on-rails - rspec assigns 将哈希键转换为字符串

Question

我有一个控制器操作，我将哈希分配给实例变量。在我的 rspec 测试文件中，我使用 assigns 来测试它，实例变量被分配给我期望的值。出于某种原因，assigns 给了我一个带有字符串键的散列。如果我在控制器中打印实例变量，我有符号键

请在下面找到代码。它被简化了。

class TestController < ApplicationController
  def test
    @test_object = {:id => 1, :value => 2, :name => "name"}
  end
end

我的测试文件：

describe TestController do
  it "should assign test_object" do
    get :test
    assigns(:test_object).should == {:id => 1, :value => 2, :name => "name"}
  end
end

上述测试失败并显示错误消息

expected: {:id=>1, :value=>2, :name=>"name"}
     got: {"id"=>1, "value"=>2, "name"=>"name"}

请帮助我理解它为什么这样做。

Answer 1

RSpec 从常规的 Rails 测试/单元助手中借用赋值，它使用 with_indiffer_access 返回请求的实例变量，如assigns(:my_var).

Hash#with_indifferent_access返回哈希的键字符串化版本（深层副本），其副作用是对作为哈希的实例变量的键进行字符串化。

If you try to match the entire hash, it will fail, but it works if you are checking the values of specific keys, whether they're a symbol or a string.

Maybe an example will help clarify:

{:a => {:b => "bravo"}}.with_indifferent_access => {"a"=>{"b"=>"bravo"}} 
{:a => {:b => "bravo"}}.with_indifferent_access[:a][:b] => "bravo"