使用 RSpec 测试破坏

Question

I have this in controllers

   def destroy
        @post = Post.find(params[:id])
        @post.destroy
    end

But I'm lost as to how to actually test if it works. Any pointers would be highly appreciated: I currently have this in my RSpec file:

require 'rails_helper'


RSpec.describe Post, type: :model do
  it "must have a title" do
    post= Post.create
    expect(post.errors[:title]).to_not be_empty
  end 
  it "must have a description" do
    post= Post.create
    expect(post.errors[:description]).to_not be_empty
  end 
  it "must have a location" do
    post= Post.create
    expect(post.errors[:location]).to_not be_empty
  end 
  it "must have an image" do
    post= Post.create
    expect(post.errors[:image]).to_not be_empty
  end 
  it "can be destroyed" do
    post= Post.destroy

  end 
end 

Answer 1

You can check if the count of thing has change by -1, like this:

expect { delete '/things', :thing => { :id => 123'} }.to change(Thing, :count).by(-1)

This means that you want to have one less 'thing' and and is ensuring that something has been deleted.

If you want to ensure that specific "thing" was deleted, you can create one before the test, pass the "thing" id as param, and ensure that this doesn't exists on database, like this:

thing = create(:thing)
delete '/things', :thing => { :id => thing.id'}

expect(Thing.find_by(id: thing.id)).to be_nil

Answer 2

As pointed out, if you use request specs ( see https://relishapp.com/rspec/rspec-rails/v/3-9/docs/request-specs/request-spec ) you can easily call the API that should delete the model, and then do an ActiveRecord query to expect no results.

require "rails_helper"

RSpec.describe "delete thing api" do

  it "deletes thing" do

    // Create a thing with a factory of your choice here

    delete "/things", :thing => {:id => 1}

    expect(Thing.all.count).to be 0
  end
end