simple_form: SystemStack Error when using config.wrappers in initializer (Rails 6.1 / Ruby 3)

Environment

• Ruby 3.0.0
• Rails 6.1.0
• Simple Form 5.0.3

This is a project which works beautifully with Rails 6.0 / Ruby 2.7.2 - we’re upgrading it but having two issue which I think may be related (could be wrong, of course!)

Current behavior

• Starting Rails server or console with SimpleForm config including wrappers config causes a SystemStackError
• Starting Rails server or console with SimpleForm config NOT including wrappers config causes the application to hang on Rails.application.initialize
• Starting Rails server or console WITHOUT SimpleForm: no problems

Here’s the SystemStackError trace:

➜ fanco git:(ruby3) ✗ rails c /Users/terry/.rvm/gems/ruby-3.0.0/gems/simple_form-5.0.3/lib/simple_form/wrappers/builder.rb:51:in use’: stack level too deep (SystemStackError) from /Users/terry/sites/fanco/config/initializers/simple_form.rb:60:in block (2 levels) in <top (required)>' from /Users/terry/.rvm/gems/ruby-3.0.0/gems/simple_form-5.0.3/lib/simple_form.rb:241:in build’ from /Users/terry/.rvm/gems/ruby-3.0.0/gems/simple_form-5.0.3/lib/simple_form.rb:231:in wrappers' from /Users/terry/sites/fanco/config/initializers/simple_form.rb:16:in block in <top (required)>’ from /Users/terry/.rvm/gems/ruby-3.0.0/gems/simple_form-5.0.3/lib/simple_form.rb:289:in setup' from /Users/terry/sites/fanco/config/initializers/simple_form.rb:10:in <top (required)>’ from /Users/terry/.rvm/gems/ruby-3.0.0/gems/activesupport-6.1.0/lib/active_support/dependencies.rb:326:in load' from /Users/terry/.rvm/gems/ruby-3.0.0/gems/activesupport-6.1.0/lib/active_support/dependencies.rb:326:in block in load’ … 42 levels… from /Users/terry/.rvm/gems/ruby-3.0.0/gems/railties-6.1.0/lib/rails/command.rb:50:in invoke' from /Users/terry/.rvm/gems/ruby-3.0.0/gems/railties-6.1.0/lib/rails/commands.rb:18:in <top (required)>’ from bin/rails:4:in require' from bin/rails:4:in <main>'`

Here’s config/initializers/simple_form.rb (with commented lines omitted)

SimpleForm.setup do |config|
  config.wrappers :default,
                  class: :input,
                  hint_class: :field_with_hint,
                  error_class: :field_with_errors,
                  valid_class: :field_without_errors do |b|

    b.use :html5
    b.use :placeholder
    b.optional :maxlength
    b.optional :minlength
    b.optional :pattern
    b.optional :min_max
    b.optional :readonly
    b.use :label_input
    b.use :hint,  wrap_with: { tag: :span, class: :hint }
    b.use :error, wrap_with: { tag: :span, class: :error }
  end

  config.default_wrapper = :default
  config.boolean_style = :nested
  config.button_class = 'btn'
  config.error_notification_tag = :div
  config.error_notification_class = 'error_notification'
  config.browser_validations = false
  config.boolean_label_class = 'checkbox'
end

Here’s my Gemfile:

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

gem 'acts_as_list'
gem 'acts-as-taggable-on', git: 'https://github.com/morsedigital/acts-as-taggable-on'
gem 'after_party'
gem 'ancestry'
gem 'aws-sdk-s3'
gem 'axlsx', git: 'https://github.com/randym/axlsx.git', ref: 'c8ac844'

gem 'better_errors'
gem "binding_of_caller"
gem "browser", ">=2.5.1"
gem 'bullet', group: :development
gem 'byebug', platforms: [:mri, :mingw, :x64_mingw], groups: [:development, :test]

gem 'capistrano'
gem 'capybara', '>= 2.15', groups: [:test]
gem 'caxlsx_rails'
gem 'codacy-coverage', require: false
gem 'coveralls', groups: [:test]

gem 'decent_exposure'
gem 'devise'
gem 'dotenv-rails', require: 'dotenv/rails-now'

gem 'elasticsearch-model'
gem 'elasticsearch-rails'

gem 'faker'
gem 'factory_bot_rails'
gem 'faraday_middleware-aws-sigv4'
gem 'friendly_id'

gem 'google_drive'
gem 'gretel'
gem 'guard-rspec', groups: [:test]
gem 'guard-rubocop', groups: [:test]

gem 'i18n-debug', groups: [:development, :test]
gem 'i18n-tasks', groups: [:development, :test]
gem "iconv"
gem 'image_processing', '~> 1.2'
gem 'instagram'

gem 'jbuilder', '~> 2.5'

gem 'kaminari'

gem 'listen', groups: [:development]
gem "letter_opener", :group => :development

gem 'mini_magick'
gem 'morse_active_record_helpers'
gem 'morse_spec_helpers', '>=4.0.0', groups: [:development]
gem 'mysql2'

gem 'newrelic_rpm'

gem 'overcommit', groups: [:development]
gem 'omniauth'
gem 'omniauth-facebook'
gem 'omniauth-instagram'
gem 'omniauth-google-oauth2', '~> 0.8.0'

gem 'percy-capybara', '~> 4.0.0'
gem 'pry-byebug'
gem 'puma', '~> 3.11'

gem 'rails', '>=6.1'
gem 'rails_real_favicon', groups: [:development]
gem 'ransack'
gem 'recaptcha', require: 'recaptcha/rails'
gem 'record_tag_helper'
gem 'rest-client'
gem 'rollbar'
gem "roo", "~> 2.8.0"
gem 'rspec-rails', groups: [:development, :test]
gem 'rubocop', groups: [:test]
gem 'ruby-graphviz'
gem 'rubyzip', '>= 1.2.1'

gem 'sass-rails', '~> 5.0'
gem 'searchkick'
gem 'serviceworker-rails'
gem 'shoulda-matchers', groups: [:test]
gem 'sidekiq'
gem 'simple_form' 
gem 'simplecov', groups: [:test]
gem 'spring', groups: [:test]
gem 'spring-commands-rspec', groups: [:test]

gem 'turbolinks', '~> 5'
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

gem 'web-console', github: 'rails/web-console', groups: [:development]
gem 'webdrivers', '~>3.0'
gem 'webpacker'
gem 'webpush'
gem 'workflow-activerecord'

Expected behavior

For everything to work with the SimpleForm loveliness that we use in all our projects (including other Ruby 3.0.0 / Rails 6.1 ones)

I’ve tried digging into the SimpleForm code to see if I can figure out what’s making it loop (I think it’s a loop), but not getting anywhere fast. any pointers would be appreciated!