Question

When I’m trying to seed my database, I started getting this error:

rake aborted!
undefined method `to_d' for 0:Fixnum

This started after I added this method that strips my decimal columns of commas if their present (2,000.00 < 2000.00):

def cost=(num)
   num.gsub!(',','') if num.is_a?(String)
   self[:cost] = num.to_d
end

I have this same method for each of the columns of my Product model:

create_table :products do |t|
  t.decimal :cost, :precision => 11, :scale => 2
  t.decimal :tax_rate, :precision => 8, :scale => 2
  t.decimal :shipping_cost, :precision => 8, :scale => 2
  t.decimal :cost_per_unit, :precision => 11, :scale => 2
  t.decimal :unit_amount, :precision => 16

Now looking at the trace (at https://gist.github.com/2265580) I think the problem may be my default_to_zero_if_necessary method:

Product.rb

before_validation :default_to_zero_if_necessary, :on => :create

private

  def default_to_zero_if_necessary
    self.tax_rate = 0 if self.tax_rate.blank?
    self.shipping_cost = 0 if self.shipping_cost.blank?
    self.cost = 0 if self.cost.blank?
    self.cost_per_unit = 0 if self.cost_per_unit.blank?
    self.unit_amount = 0 if self.unit_amount.blank?
  end

Maybe I can’t use my default_to_zero_if_necessary method like this anymore? What’s really going on here? I’m not entirely sure.

Answer 1

Would you mind setting cost to 0.0 instead of 0?

self.cost = 0.0 if self.cost.blank?

That should solve your problem.