When used with sunspot gem: method_missing_without_enumerated_attribute already exists.

[aisrael]

Scenario:

Use enumerated_attribute on some models, then try to use sunspot gem.

When you declare a model to be searchable using sunspot, then attempt to do rake sunspot:solr:reindex to build your index, you get:

rake aborted!
method_missing_without_enumerated_attribute already exists.  Circular references not permitted.
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/meta_programming-0.2.2/lib/meta_programming/object.rb:43:in `block in safe_alias_method_chain'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/meta_programming-0.2.2/lib/meta_programming/object.rb:39:in `class_eval'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/meta_programming-0.2.2/lib/meta_programming/object.rb:39:in `safe_alias_method_chain'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/meta_programming-0.2.2/lib/meta_programming/object.rb:66:in `define_chained_method'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute/integrations/active_record.rb:107:in `singletonclass'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute/integrations/active_record.rb:94:in `block in define_enumerated_attribute_new_method'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute/integrations/active_record.rb:93:in `class_eval'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute/integrations/active_record.rb:93:in `define_enumerated_attribute_new_method'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute/attribute.rb:45:in `create_enumerated_attribute'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/bundler/gems/enumerated_attribute-84221b872f7f/lib/enumerated_attribute.rb:13:in `enumerated_attribute'
/Users/aisrael/workspaces/rails/likejobs/web/app/models/user.rb:22:in `<class:User>'
/Users/aisrael/workspaces/rails/likejobs/web/app/models/user.rb:1:in `<top (required)>'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:251:in `require'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:251:in `block in require'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:236:in `load_dependency'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:251:in `require'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/sunspot_rails-1.3.3/lib/sunspot/rails/tasks.rb:34:in `block (3 levels) in <top (required)>'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/sunspot_rails-1.3.3/lib/sunspot/rails/tasks.rb:34:in `each'
/Users/aisrael/.rvm/gems/ruby-1.9.3-p327/gems/sunspot_rails-1.3.3/lib/sunspot/rails/tasks.rb:34:in `block (2 levels) in <top (required)>'
Tasks: TOP => sunspot:solr:reindex => sunspot:reindex
(See full trace by running task with --trace)

This happens even if the searchable model itself doesn't declare any enumerated_attributes.

[aisrael]

I just discovered that you don't even need sunspot gem. If you have

class User < ActiveRecord::Base
    enum_attr :test, %w(a b c)

Then it's enough to go

$ rails console
> class User
>   enum_attr :foo, %w(d e f)

And you'll get the same error. From what I can tell, in enumerated_attribute/integrations/active_record.rb the following guard:

unless private_method_defined?(:method_missing_without_enumerated_attribute)

is failing.

[aisrael]

Found it. The check in meta_programming/lib/meta_programming/object.rb:42 checks for both public and private methods:

if (method_defined?(method_name_with_ext) || private_method_defined?(method_name_with_ext))
    raise(MetaProgramming::AliasMethodChainError, "#{method_name_without_ext} already exists.  Circular references not permitted.")

Whereas the guard in enumerated_attribute/integrations/active_record.rb:106 only checks for private methods. It should be changed to:

unless method_defined?(:method_missing_without_enumerated_attribute) || private_method_defined?(:method_missing_without_enumerated_attribute)

Forking, patching, submitting a pull request.