How to properly do model testing with ActiveStorage in rails?

Question

I have just switched to using ActiveStorage on rails 5.1.4 and I am new to TDD and struggling to figure out how to test a model that has_one_attached :avatar

Answer 1

Here is how I solved it

# model
class Report < ApplicationRecord
  has_one_attached :file
end

# factory
FactoryBot.define do
  factory :report, class: Report do 
    any_extra_field { 'its value' }
  end
end

# spec
require 'rails_helper'
RSpec.describe Report, type: :model do
  context "with a valid file" do
    before(:each) do
      @report = create(:report)
    end

    it "is attached" do
      @report.file.attach(
        io: File.open(Rails.root.join('spec', 'fixtures', 'file_name.xlsx')),
        filename: 'filename.xlsx',
        content_type: 'application/xlsx'
      )
      expect(@report.file).to be_attached
    end
  end
end

I hope it help you