Cucumber factory Show archive.org snapshot supports polymorphic associations out of the box. Just keep in mind that you need to use named associations for this purpose.

class Person < ApplicationModel
  has_many :buildings, inverse_of: :owner
end

class Company < ApplicationModel
  has_many :buildings, inverse_of: :owner
end

class Building < ApplicationModel
  belongs_to :owner, optional: true, polymorphic: true
end

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

Read more Show archive.org snapshot

Works

Given there is a person with the name "Nice person"
  And there is a building with the owner "Nice person"

Does not work

Given there is a person with the name "Nice person"
  And there is a building with the owner above