require "test_helper" class UuidFormatTest < ActiveSupport::TestCase test "valid matches canonical UUID values" do uuid = SecureRandom.uuid assert UuidFormat.valid?(uuid) assert UuidFormat.valid?(uuid.upcase) end test "valid rejects non UUID values" do refute UuidFormat.valid?(nil) refute UuidFormat.valid?("") refute UuidFormat.valid?("not-a-uuid") refute UuidFormat.valid?("#{SecureRandom.uuid}-extra") end end