模拟Rspec中的多个方法，其中第一个方法接受参数

class Calculator
  def add(a, b)
    a + b
  end

  def subtract(a, b)
    a - b
  end

  def multiply(a, b)
    a * b
  end
end

require 'rspec'

RSpec.describe Calculator do
  let(:calculator) { Calculator.new }

  it 'should add two numbers' do
    # 模拟第一个方法接受参数
    allow(calculator).to receive(:add).with(3, 4).and_return(7)

    expect(calculator.add(3, 4)).to eq(7)
  end

  it 'should subtract two numbers' do
    expect(calculator.subtract(5, 2)).to eq(3)
  end

  it 'should multiply two numbers' do
    expect(calculator.multiply(2, 3)).to eq(6)
  end
end