FactoryGirl: ActiveRecord::AssociationTypeMismatch: User expected, got #<Class:0x007>

Question

I have a simple User model with a has_many :photos association. When I try to FactoryGirl.create(:user) I get the error below. Any idea?

# user.rb
has_many :photos, dependent: :destroy

# photo.rb
belongs_to :user


FactoryGirl.define do
  factory :user do
    email '[email protected]'
    after_build do |user|
      user.photos << FactoryGirl.build(:photo, user: user)
    end
  end

  factory :photo do
    photo File.new(File.join(::Rails.root.to_s, "/factories/images", "avatar1.jpg"), 'rb')
  end

Error output.

ruby-1.9.2-p290 :015 > b = FactoryGirl.create(:user)
ActiveRecord::AssociationTypeMismatch: User(#70183166983920) expected, got #    <Class:0x007fa995612538>(#70183166186140)
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activerecord-3.2.8/lib/active_record/associations/association.rb:204:in `raise_on_type_mismatch'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activerecord-3.2.8/lib/active_record/associations/belongs_to_association.rb:6:in `replace'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activerecord-3.2.8/lib/active_record/associations/singular_association.rb:17:in `writer'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activerecord-3.2.8/lib/active_record/associations/builder/association.rb:51:in `block in define_writers'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:16:in `block (2 levels) in object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:15:in `each'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:15:in `block in object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:14:in `tap'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:14:in `object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/evaluation.rb:12:in `object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/strategy/build.rb:9:in `result'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory.rb:42:in `run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory_runner.rb:23:in `block in run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activesupport-3.2.8/lib/active_support/notifications.rb:125:in `instrument'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory_runner.rb:22:in `run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/strategy_syntax_method_registrar.rb:19:in `block in define_singular_strategy_method'
    ... 8 levels...
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:15:in `block in object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:14:in `tap'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/attribute_assigner.rb:14:in `object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/evaluation.rb:12:in `object'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/strategy/create.rb:9:in `result'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory.rb:42:in `run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory_runner.rb:23:in `block in run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/activesupport-3.2.8/lib/active_support/notifications.rb:125:in `instrument'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/factory_runner.rb:22:in `run'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/factory_girl-4.1.0/lib/factory_girl/strategy_syntax_method_registrar.rb:19:in `block in define_singular_strategy_method'
    from (irb):15
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/railties-3.2.8/lib/rails/commands/console.rb:47:in `start'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/railties-3.2.8/lib/rails/commands/console.rb:8:in `start'
    from /Users/user/.rvm/gems/ruby-1.9.2-p290@site/gems/railties-3.2.8/lib/rails/commands.rb:41:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'ruby-1.9.2-p290 :016 > #<Class:0x007fa995612538>

Answer 1

Solved. I should have used newer after(:create) instead of older after_build.

Answer 2

I was having a similar problem and here's the code block I used to solve it:

after(:create) do |user|
  user.photos << FactoryGirl.create :photo, user: user
end