RSpec：如何正确模拟#destroy失败

Question

我很难在控制器中模拟destroy方法的失败。

我的控制器的销毁看起来像这样：

def destroy
   project = Project.find(params[:id])
   project.destroy

  if project.destroyed?
    render json: {
      project: nil,
      message: "The project was successfully deleted"
    }
  else
    render json: {
      message: "Could not delete project",
    }, status: :unprocessable_entity
  end
end

我正在尝试在测试中的else块中呈现json，但无法完成。 到目前为止，特定测试如下所示：

describe "DELETE #destroy" do

 let!(:project) { create(:project, :open) }

  context "when invalid" do

   it "returns an error if the project was not deleted" do
     expect(Project).to receive(:find).with(project.id.to_s).and_call_original
     expect(project).to receive(:destroy).and_return(false)
     delete :destroy, id: project
   end

 end
end

测试要么返回“幸福的道路”，要么给我错误。 在这一刻：

 Failure/Error: expect(project).to receive(:destroy).and_return(false)

       (#<Project:0x007f87cf5d46a8>).destroy(*(any args))
           expected: 1 time with any arguments
           received: 0 times with any arguments

如果有人能指出正确的方向并说明如何模拟422，我将不胜感激！

Answer 1

您希望一开始就允许，而不是期望。 期望是断言的一部分。

it "returns an error if the project was not deleted" do
  allow(Project).to receive(:find).with(project.id.to_s).and_call_original
  allow(project).to receive(:destroy).and_return(false)

  delete :destroy, id: project

  expect(Project).to have_received(:find)
  expect(project).to have_received(:destroy)
end

我假设你是对的

allow(Project).to receive(:find).with(project.id.to_s).and_call_original

但我从未见过，我通常会

allow(Project).to receive(:find).with(project.id.to_s).and_return(project)