I can across an error in Rails3 today when I was trying to implement a scope.
When trying to run that Scope I’d get
undefined method 'includes_values' for <#Product:rarrarrar> It had me scratching my head since the trace showed me nothing. So I went through the activerecord codebase, and sure enough it was something stupid that I did. The scope should return an ActiveRecord object, and not a result set. So simply removing the .first off my scope resulting in a working scope
Its a simple fix, but googling came up with nothing. So I hope this helps someone else who comes across this error.