Rails 7.0で"DEPRECATION WARNING: image/jpg is not a valid content type"のようなエラーが出た場合

発生した問題

Rails 7.0にバージョンアップしてテストを実行したら以下のようなエラーメッセージが出ました。

DEPRECATION WARNING: image/jpg is not a valid content type, it should not be used when creating a blob, and support for it will be removed in Rails 7.1. If you want to keep supporting this content type past Rails 7.1, add it to `config.active_storage.variable_content_types`. Dismiss this warning by setting `config.active_storage.silence_invalid_content_types_warning = true`. (called from public_send at /Users/jnito/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/factory_bot-6.2.0/lib/factory_bot/attribute_assigner.rb:16)

原因

FactoryBotのコードで書いたContent typeが不正でした（'image/jpg'）。

FactoryBot.define do
  factory :note do
    message { "My important note." }
    association :project
    user { project.owner }

    trait :with_attachment do
      attachment { Rack::Test::UploadedFile.new("#{Rails.root}/spec/files/attachment.jpg", 'image/jpg') }
    end
  end
end

修正方法

Content typeを修正したら直りました（'image/jpeg'）。

 FactoryBot.define do
   factory :note do
     message { "My important note." }
     association :project
     user { project.owner }
 
     trait :with_attachment do
-      attachment { Rack::Test::UploadedFile.new("#{Rails.root}/spec/files/attachment.jpg", 'image/jpg') }
+      attachment { Rack::Test::UploadedFile.new("#{Rails.root}/spec/files/attachment.jpg", 'image/jpeg') }
     end
   end
 end

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