Rspec不查找类方法

Question

我正在为我的后端工作编写一些测试，而rspec没有找到我的方法，我遇到了一个奇怪的问题。

我编写了一个简单的类&测试来说明这个问题：

app/interactors/tmp_test.rb：

class TmpTest
  def call
    a = 10
    b = 5
    b.substract_two
    return a + b
  end

  def substract_two
    c = self - 2
    return c
  end
end

spec/interactors/tmp_test.rb：

require 'rails_helper'

describe TmpTest do
  context 'when doing the substraction' do
    it 'return the correct number' do
      expect(described_class.call).to eq(13)
    end
  end
end

产出：

TmpTest
  when doing the substraction
    return the correct number (FAILED - 1)

Failures:

  1) TmpTest when doing the substraction return the correct number
     Failure/Error: expect(described_class.call).to eq(13)

     NoMethodError:
       undefined method `call' for TmpTest:Class
     # ./spec/interactors/tmp_test.rb:6:in `block (3 levels) in <top (required)>'

Finished in 0.00177 seconds (files took 1.93 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./spec/interactors/tmp_test.rb:5 # TmpTest when doing the substraction return the correct number

Answer 1

它不是一个类方法，而是一个实例方法。您的测试应该如下所示：

describe TmpTest do
  subject(:instance) { described_class.new }

  context 'when doing the subtraction' do
    it 'returns the correct number' do
      expect(instance.call).to eq(13)
    end
  end
end

Answer 2

这真是一团糟。更正后的版本，并附有评论：

class TmpTest
  def call
    a = 10
    b = 5
    # b.substract_two # why do you call method of this class on b?!
    a + subtract_two(b)
  end

  def substract_two(from)
    from - 2
  end
end

另外:不要在方法的最后一行中使用return。