如何访问实例变量来测试spec中的`receive`？

class ExampleClass
  attr_accessor :instance_variable

  def initialize
    @instance_variable = "Hello"
  end

  def example_method
    # 代码逻辑
  end
end

# 创建实例对象
example_object = ExampleClass.new

RSpec.describe ExampleClass do
  describe "#example_method" do
    it "should receive a message" do
      expect(example_object).to receive(:example_method)
      example_object.example_method
    end
  end
end