Count instances correctly

[dacastror]

hi all, I would like to know how to count the number of instances of a definition, the "Entity Info" window appears correctly but definition.count_instances do not, is there anything in the API or somewhere to get this information? attached skp file with which I am doing tests

instances.skp
thank you very much in advance for the help
(google translator)

[Dan Rathbun]

See how I did it in this plugin I wrote for Ash Scott:
[Plugin] Multiple Component Edit Warning

[dacastror]

Thanks Dan, this can give me a hint, I'm testing with the definition given there, but in my testing model (instances.skp) gives me a wrong number of instances, sometimes less or sometimes more, I do not know if I'm misapplying the definition count_instances ()

# you must have a selected instance
def count_instances()
  num = 0
  if @editpath.size == 1
    i = @editpath.last
  else
    revpath = @editpath.reverse
    i = revpath.shift
  end
  if i.is_a?(Sketchup;;ComponentInstance)
    num = i.definition.instances.size
  elsif i.is_a?(Sketchup;;Group)
    num = i.entities.parent.instances.size
  end
  if @editpath.size > 1
    revpath.each {|i|
      if i.is_a?(Sketchup;;ComponentInstance)
        num = num * i.definition.instances.size
      elsif i.is_a?(Sketchup;;Group)
        num = num * i.entities.parent.instances.size
      end
    }
  end
  return num
end

mod = Sketchup.active_model 
sel = mod.selection

ruta = mod.active_path
(ruta) ? (ruta[ruta.size] = sel[0]) ; (ruta = []; ruta[0] = sel[0])
@editpath = ruta
count_instances()