ruby-on-rails - Rspec:如何测试私有(private)方法中引发的异常？

Question

在私有(private)方法中测试异常时出错。如何测试从公共(public)方法调用的私有(private)方法引发的异常？

公开

def public_method
    private_method
end

私有(private)

  def private_method
    tries = 0
    begin
      raise Product::StaleObjectError.new("Product is changed while you were editing") if stale_object?
      // Do some work
      raise Exception.new("Total amount used is greater than approved") if total_approved < 0

      // Save Product
    rescue Product::StaleObjectError => e
      if tries < MAX_RETRIES
        tries += 1
        sleep(1 + tries)
        reload
        retry
      else
        raise Product::StaleObjectError("Product is changed while you were editing")
      end
    end
    attributes
  end

测试用例:

  before(:each) do
    @prod_v1 = Product.new
  end
  it 'if product stale, then an exception should raise' do
    Product.any_instance.stub(:stale_object?).and_return(true)
    expect_any_instance_of(Product).to receive(:private_method).and_raise(Product::StaleObjectError.new("Product is changed while you were editing"), nil)
    @prod_v1.public_method
  end

测试用例出现以下错误

 Failure/Error: @product_v1.private_method
 Product::StaleObjectError:
   Product is changed while you were editing
 # ./app/models/product.rb:10:in `private_method'
 # ./spec/models/product_spec.rb:67:in `block (4 levels) in <top (required)>'

我尝试更改测试用例的结构，但仍然出错。

  it 'if product stale, then an exception should raise' do
   Product.any_instance.stub(:stale_object?).and_return(true)
    expect_any_instance_of(Product).to receive(:private_method).and_raise(Product::StaleObjectError.new(nil, nil))
    @prod_v1.public_method
  end

错误

    Failure/Error: expect_any_instance_of(Product).to receive(:private_method).and_raise(Product::StaleObjectError.new(nil, nil))
 ArgumentError:
   wrong number of arguments (2 for 0..1)

Answer 1

尝试 and_raise(Product::StaleObjectError.new(nil, nil))

看到这个问题我问了一会儿关于同一个问题:

Rspec - wrong number of arguments when raising error