Problem with dynamic attributes in Rails

[daniel-rikowski]

I think I found a new problem in the latest version.

This line fails in Rails (4.0.2)

alias_method :"old_#{attribute}=", :"#{attribute}="

I think it is because Rails creates the methods the first time method_missing is called:

def method_missing(method, *args, &block) # :nodoc:
  unless self.class.attribute_methods_generated?
    self.class.define_attribute_methods
    # More stuff removed
  else
    super
  end
end

Since date_time_attribute is called before method_missing can be called on any instance, the attribute methods don't yet exist.

But I'm not 100% sure that this is the root cause

I'm also not sure how this can be solved, but at least it is easy to reproduce, just put this in any Rails model:

include DateTimeAttribute
date_time_attribute :created_at

You'll get a NameError undefined method `created_at=' as soon as the class is loaded.

[daniel-rikowski]

I just checked, calling define_attribute_methods manually solves the problem, but that feels really hacky :)

define_attribute_methods
include DateTimeAttribute
date_time_attribute :created_at

[einzige]

Thanks Daniel! Gimme a sec, I'll fix that

[RobertGauld]

einzige any idea when you'll release this fix?

[einzige]

@robertgauld , @daniel-rikowski sorry guys, forgot about it. I will do today.

[einzige]

Thanks guys, bundled 0.0.6. @daniel-rikowski you were 100% right, I was able to reproduce it the way you described and fix it the way you proposed.

https://github.com/einzige/date_time_attribute/commit/923f7c2418f4e9f606197151014031bac0a3b658#diff-1e95ae95ab1149cac143cff383f33c7eR1