fix validation on parent for Rails 5

[pacMakaveli]

This ( temporarily ) fixes the issue for Rails 5. I'm running out of time and I don't have time to test for Rails 4 right now, but will do tomorrow. I will also find a way to support both in case this fails on Rails 4 ( maybe because required is an unknown key for belongs_to on Rails 4 )

[pacMakaveli]

Also, this fixes #195

[mceachen]

Thanks, but we'll need to make it conditional. Rails 3 and 4 are still supported.

[jayfredlund]

@mcheachen -- not sure if you have a preferred option here, but I'm building something out so I can continue using this with a new project of mine, and was thinking I could build it in a way that you'd potentially use:

Options (in no particular order of preference):

belongs_to_options = { class_name: _ct.model_class.to_s,
                       foreign_key: _ct.parent_column_name,
                       inverse_of: :children,
                       touch: _ct.options[:touch],
                       optional: true }
begin
  belongs_to :parent, belongs_to_options
rescue ArgumentError => e
  belongs_to :parent, belongs_to_options.except(:optional)
end

belongs_to_options = { class_name: _ct.model_class.to_s,
                       foreign_key: _ct.parent_column_name,
                       inverse_of: :children,
                       touch: _ct.options[:touch] }

if ActiveRecord::Associations::Builder::BelongsTo.valid_options([]).include?(:optional)
  belongs_to_options.merge({optional: true})
end

belongs_to :parent, belongs_to_options

belongs_to_options = { class_name: _ct.model_class.to_s,
                       foreign_key: _ct.parent_column_name,
                       inverse_of: :children,
                       touch: _ct.options[:touch] }

if Rails.version.to_i >= 5
  belongs_to_options.merge({optional: true})
end

belongs_to :parent, belongs_to_options

Similar to what you've done in other examples with the has_many ordering, it'd probably be good to do something similar and move all of the conditional logic into the support file:

# model.rb
belongs_to :parent, belongs_to_opts({ class_name: _ct.model_class.to_s,
                                      foreign_key: _ct.parent_column_name,
                                      inverse_of: :children,
                                      touch: _ct.options[:touch] })

# support.rb
def belongs_to_opts(opts)
   # add the "optional" key and logic checks
end 

Any thoughts?

[mceachen]

Thanks! I'd prefer the approach that's going to be easiest to grok, test, and support in the future. The prior approach want particularly elegant, but expedient. What do you prefer?

[jayfredlund]

@mceachen I've created PR #204 to handle this. I decided to simply be consistent with the existing support methods -- that way, reading the belongs_to in the model.rb code shows everything being added, and the support method will just rip out the optional tag if the ActiveRecord version is < 5 (belongs_to being optional is default behavior in versions prior to 5).

The edge tests are obviously failing on Travis still, since the version of rspec-rails we're using does not support ActiveRecord > 4.3.