class Shoulda::Matchers::ActiveRecord::HaveDbColumnMatcher

def correct_scale?
  return true unless @options.key?(:scale)
  if matched_column.scale.to_s == @options[:scale].to_s
    true
  else
    @missing = "#{model_class} has a db column named #{@column} " <<
               "of scale #{matched_column.scale}, not #{@options[:scale]}."
    false
  end
end