"wrong number of arguments (1 for 0)" error loading file input field with Rails 4, Formtastic and Paperclip

Question

I'm trying to create a simple upload form for images using Paperclip and Formtastic in Rails 4. I'm getting this error message on loading the form's view:

wrong number of arguments (1 for 0) 

Here's my _form.html.erb:

<%= semantic_form_for @image, :html => { :multipart => true } do |f| %>
    <%= f.input :attachment, :as => :file %>
    <%= f.submit %>
<% end %>

It works fine when I use the regular rails file_field helper instead like so:

<%= f.file_field :attachment %>

Here's my model:

class Image < ActiveRecord::Base
  has_attached_file :attachment, :styles => { :medium => "300x300>", :thumb => "100x100>" }, :default_url => "/images/:style/missing.png"
  validates_attachment_content_type :attachment, :content_type => /\Aimage\/.*\Z/
end

Here's part of my gemfile:

ruby "2.1.0"
gem 'rails', '4.0.2'
gem "formtastic", github: "justinfrench/formtastic"
gem "paperclip", github: "thoughtbot/paperclip"

Here's the full trace:

paperclip (4.1.1) lib/paperclip/has_attached_file.rb:83:in `block in add_required_validations'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:39:in `call'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:39:in `validator_relevant?'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:27:in `block in validations'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:26:in `select'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:26:in `validations'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:129:in `validations?'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/validations.rb:136:in `required?'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/labelling.rb:25:in `requirement_text_or_proc'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/labelling.rb:29:in `requirement_text'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/labelling.rb:20:in `label_text'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/labelling.rb:9:in `label_html'
formtastic (2.3.0.rc2) lib/formtastic/inputs/file_input.rb:36:in `block in to_html'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:38:in `block in capture'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:200:in `with_output_buffer'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:38:in `capture'
formtastic (2.3.0.rc2) lib/formtastic/inputs/base/wrapping.rb:11:in `input_wrapping'
formtastic (2.3.0.rc2) lib/formtastic/inputs/file_input.rb:35:in `to_html'
formtastic (2.3.0.rc2) lib/formtastic/helpers/input_helper.rb:241:in `input'
app/views/images/_form.html.erb:4:in `block in _app_views_images__form_html_erb__2391314292381568206_2160118960'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:38:in `block in capture'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:200:in `with_output_buffer'
actionpack (4.0.2) lib/action_view/helpers/capture_helper.rb:38:in `capture'
actionpack (4.0.2) lib/action_view/helpers/form_helper.rb:435:in `form_for'
formtastic (2.3.0.rc2) lib/formtastic/helpers/form_helper.rb:167:in `block in semantic_form_for'
formtastic (2.3.0.rc2) lib/formtastic/helpers/form_helper.rb:190:in `with_custom_field_error_proc'
formtastic (2.3.0.rc2) lib/formtastic/helpers/form_helper.rb:166:in `semantic_form_for'
app/views/images/_form.html.erb:2:in `_app_views_images__form_html_erb__2391314292381568206_2160118960'
actionpack (4.0.2) lib/action_view/template.rb:143:in `block in render'
activesupport (4.0.2) lib/active_support/notifications.rb:161:in `instrument'
actionpack (4.0.2) lib/action_view/template.rb:141:in `render'
actionpack (4.0.2) lib/action_view/renderer/partial_renderer.rb:306:in `render_partial'
actionpack (4.0.2) lib/action_view/renderer/partial_renderer.rb:279:in `block in render'
actionpack (4.0.2) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.0.2) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.0.2) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'
actionpack (4.0.2) lib/action_view/renderer/partial_renderer.rb:278:in `render'
actionpack (4.0.2) lib/action_view/renderer/renderer.rb:47:in `render_partial'
actionpack (4.0.2) lib/action_view/helpers/rendering_helper.rb:27:in `render'
app/views/images/new.html.erb:3:in `_app_views_images_new_html_erb__3497169186049415334_2160262000'
actionpack (4.0.2) lib/action_view/template.rb:143:in `block in render'
activesupport (4.0.2) lib/active_support/notifications.rb:161:in `instrument'
actionpack (4.0.2) lib/action_view/template.rb:141:in `render'
actionpack (4.0.2) lib/action_view/renderer/template_renderer.rb:49:in `block (2 levels) in render_template'
actionpack (4.0.2) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.0.2) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.0.2) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'
actionpack (4.0.2) lib/action_view/renderer/template_renderer.rb:48:in `block in render_template'
actionpack (4.0.2) lib/action_view/renderer/template_renderer.rb:56:in `render_with_layout'
actionpack (4.0.2) lib/action_view/renderer/template_renderer.rb:47:in `render_template'
actionpack (4.0.2) lib/action_view/renderer/template_renderer.rb:17:in `render'
actionpack (4.0.2) lib/action_view/renderer/renderer.rb:42:in `render_template'
actionpack (4.0.2) lib/action_view/renderer/renderer.rb:23:in `render'
actionpack (4.0.2) lib/abstract_controller/rendering.rb:127:in `_render_template'
actionpack (4.0.2) lib/action_controller/metal/streaming.rb:219:in `_render_template'
actionpack (4.0.2) lib/abstract_controller/rendering.rb:120:in `render_to_body'
actionpack (4.0.2) lib/action_controller/metal/rendering.rb:33:in `render_to_body'
actionpack (4.0.2) lib/action_controller/metal/renderers.rb:26:in `render_to_body'
actionpack (4.0.2) lib/abstract_controller/rendering.rb:97:in `render'
actionpack (4.0.2) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:41:in `block (2 levels) in render'
activesupport (4.0.2) lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
/Users/Sebastian/.rvm/rubies/ruby-2.1.0/lib/ruby/2.1.0/benchmark.rb:294:in `realtime'
activesupport (4.0.2) lib/active_support/core_ext/benchmark.rb:12:in `ms'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:41:in `block in render'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:84:in `cleanup_view_runtime'
activerecord (4.0.2) lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:40:in `render'
actionpack (4.0.2) lib/action_controller/metal/implicit_render.rb:10:in `default_render'
actionpack (4.0.2) lib/action_controller/metal/implicit_render.rb:5:in `send_action'
actionpack (4.0.2) lib/abstract_controller/base.rb:189:in `process_action'
actionpack (4.0.2) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.0.2) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (4.0.2) lib/active_support/callbacks.rb:413:in `_run__1520582927916815285__process_action__callbacks'
activesupport (4.0.2) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.2) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (4.0.2) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.0.2) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.0.2) lib/action_controller/metal/params_wrapper.rb:245:in `process_action'
activerecord (4.0.2) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.0.2) lib/abstract_controller/base.rb:136:in `process'
actionpack (4.0.2) lib/abstract_controller/rendering.rb:44:in `process'
actionpack (4.0.2) lib/action_controller/metal.rb:195:in `dispatch'
actionpack (4.0.2) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.0.2) lib/action_controller/metal.rb:231:in `block in action'
actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:80:in `call'
actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:80:in `dispatch'
actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:48:in `call'
actionpack (4.0.2) lib/action_dispatch/journey/router.rb:71:in `block in call'
actionpack (4.0.2) lib/action_dispatch/journey/router.rb:59:in `each'
actionpack (4.0.2) lib/action_dispatch/journey/router.rb:59:in `call'
actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:680:in `call'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `catch'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
rack (1.5.2) lib/rack/etag.rb:23:in `call'
rack (1.5.2) lib/rack/conditionalget.rb:25:in `call'
rack (1.5.2) lib/rack/head.rb:11:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/flash.rb:241:in `call'
rack (1.5.2) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.5.2) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/cookies.rb:486:in `call'
activerecord (4.0.2) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.0.2) lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in `call'
activerecord (4.0.2) lib/active_record/migration.rb:369:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.0.2) lib/active_support/callbacks.rb:373:in `_run__4230588509163931695__call__callbacks'
activesupport (4.0.2) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.2) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/reloader.rb:64:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.0.2) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.0.2) lib/rails/rack/logger.rb:20:in `block in call'
activesupport (4.0.2) lib/active_support/tagged_logging.rb:67:in `block in tagged'
activesupport (4.0.2) lib/active_support/tagged_logging.rb:25:in `tagged'
activesupport (4.0.2) lib/active_support/tagged_logging.rb:67:in `tagged'
railties (4.0.2) lib/rails/rack/logger.rb:20:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
rack (1.5.2) lib/rack/runtime.rb:17:in `call'
activesupport (4.0.2) lib/active_support/cache/strategy/local_cache.rb:83:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
actionpack (4.0.2) lib/action_dispatch/middleware/static.rb:64:in `call'
rack (1.5.2) lib/rack/sendfile.rb:112:in `call'
railties (4.0.2) lib/rails/engine.rb:511:in `call'
railties (4.0.2) lib/rails/application.rb:97:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
rack (1.5.2) lib/rack/content_length.rb:14:in `call'
rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service'
/Users/Sebastian/.rvm/rubies/ruby-2.1.0/lib/ruby/2.1.0/webrick/httpserver.rb:138:in `service'
/Users/Sebastian/.rvm/rubies/ruby-2.1.0/lib/ruby/2.1.0/webrick/httpserver.rb:94:in `run'
/Users/Sebastian/.rvm/rubies/ruby-2.1.0/lib/ruby/2.1.0/webrick/server.rb:295:in `block in start_thread'

Am I missing something obvious or are some of the gem versions not compatible?

Any help appreciated!

Answer 1

It seems like any paperclip version greater than 4.0 doesn't play well with formtastic. I experienced this problem with I tried updating the paperclip version '>= 4.1', I have to rollback to '~> 3.5' get it working again.

Have you tried using older paperclip version?

Answer 2

You can also workaround this issue by adding the :required parameter to the formtastic call. So, for example, this:

f.input :image, :as => :file

becomes this:

f.input :image, :as => :file, :required => false

The bug report on the Formtastic project is here: bug #999