[RAILS] Memorandum (task: model test code)

I forgot the model test code with the image file, so I will output it.

Create an images directory in the public directory to place test images in your application files

Place images in the created images directory Example: (public/images/test image file)

class Item < ApplicationRecord
  belongs_to :user
  has_one_attached :image

abridgement
  validates :image, presence: true
end

validates seemed to be good with presence: true.

Write a description to open the image in the corresponding factories directory

after method

A specified process can be executed after any process By doing after (: build), you can execute the specified process after the instance is built.

FactoryBot.define do
  factory :item do
    
abridgement

    after(:build) do |item|
      item.image.attach(io: File.open('public/images/Test image file'), filename: 'Test image file')
    end
  end
end

# io: File.File with the path set by open (public/images/test_image.png), test_image.Save as png file name

How to write in the file that describes the test code (item_spec.rb file this time)

abridgement
      it 'Cannot be saved if name is empty' do
        @item.name = ''
        @item.valid?
        expect(@item.errors.full_messages).to include("Name can't be blank")
      end
      it 'Cannot be saved without the product image' do
        @item.image = nil #← When using Active Storage""If so, an error will occur, so use nil to create a blank.
        @item.valid?
        expect(@item.errors.full_messages).to include("Image can't be blank")
      end

abridgement

Until now, it was unified with "", but I learned from this test code. I think there are other ways to apply validation and write test code, but for the time being, the test code has turned green, so it seems to be working.