Inheritable Attributes nil check?

[MichaelBolton]

After upgrading from Ruby 2.7 to Ruby 3.2, I started getting crash on this bit of code, somewhere around line 40 of module_inheritable_attributes.rb.

When @mattr_inheritable_attrs is nil, the iterator bombs out (which is a bit of a surprise to me; I'd assume it would simply do nothing and go along.

 def inherited(subclass)
    super
      @mattr_inheritable_attrs.each do |inheritable_attribute|
        ivar = :"@#{inheritable_attribute}"
        subclass.instance_variable_set(ivar, instance_variable_get(ivar).clone)

        if instance_variable_get(ivar).respond_to?(:merge)
          method = <<-EOM
            def self.#{inheritable_attribute}
              duplicate = ModuleInheritableAttributes.hash_deep_dup(#{ivar})
              #{ivar} = superclass.#{inheritable_attribute}.merge(duplicate)
            end
          EOM

          subclass.class_eval method
        end
    end
  end 

In my case, I worked around the issue by checking whether it's nil, and if so, skipping the iterator. Would that be the right fix?