create_list does not correctly override parameter

Author: GMoliniCreated Oct 24, 2025Updated Jun 3, 2026

Labelsbug

Description

Ive got a factory bot definition like this

FactoryBot.define do
  factory :emails_message, class: 'Emails::Message' do
    subject { Faker::Lorem.sentence }
    thread_subject { Faker::Lorem.sentence }
    from { Faker::Internet.unique.email }
    from_display_name { "#{Faker::Name.name} <#{from}>" }
  end
end

If I create a list like this:

  email_address = "[email protected]"
  emails = create_list(:emails_message, 10, from: email_address)

Its very weird because it uses the correct from in the from_display_name, but is incorrectly saved in the from attribute

If I print the emails: p emails.map { |r| [r.from, r.from_display_name] }

[["[email protected]", "Prof. Trudi Langosh <[email protected]>"], ["[email protected]", "Courtney Becker <[email protected]>"], ["[email protected]", "Ollie Steuber <[email protected]>"], ["[email protected]", "Johnathan Marvin <[email protected]>"], ["[email protected]", "Jacinto O'Reilly <[email protected]>"], ["[email protected]", "Mrs. Thanh Schinner <[email protected]>"], ["[email protected]", "Stevie Larson <[email protected]>"], ["[email protected]", "Alena Abbott MD <[email protected]>"], ["[email protected]", "Lavona Becker Ret. <[email protected]>"], ["[email protected]", "Msgr. Vada Rolfson <[email protected]>"]]

System configuration

factory_bot version: 6.2.1 rails version: 7.0.8 ruby version: 3.2.2

Edit: Ive updated factory_bot to version 6.5.5 and factory_bot_rails to 6.5.1 and it still happens

Source: thoughtbot/factory_bot

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