JSON :: ParserError：757：意外令牌

Question

我正在使用rspec测试控制器，我收到此错误 测试： quizes_controller_spec.rb：

 require 'rails_helper'
    require 'spec_helper'

RSpec.describe Api::QuizzesController, :type => :controller do
    before (:each) do
        @instructor = create(:instructor)
    end
describe "instructor_index method" do
        it "returns all quizzes of the current instructor" do
            sign_in @instructor
            @quiz = create(:quiz)
            @instructor.quizzes << @quiz
            get :instructor_index
            quiz_response = json(response.body)
            expect(response.status).to eq(200)
            expect(quiz_response[:success]).to eql(true)
            expect((quiz_response[:data][:quizzes]).first[:name]).to eql(@quiz.name)
        end
    end
end

在索引方法中，它正在渲染教师的测验： quizzes_controller.rb：

def instructor_index
            quizzes = current_instructor.quizzes
            render json: { success:true, data:{:quizzes => quizzes},info:{} }, status: 200
        end

aftur runnig rspec出现此错误：

  

Api :: QuizzesController instructor_index方法返回当前教师的所有测验        失败/错误：quiz_response = json（response.body）        JSON :: ParserError：          757：意外令牌在＆＃39;你正在redirected。＆＃39;        ＃./spec/rails_helper.rb:9:in json' # ./spec/controllers/quizzes_controller_spec.rb:60:in阻止（3级）＆＃39;

rails_helper.rb：

def json(body)  
  JSON.parse(body, symbolize_names: true) 
end