Module: Perfectline::ValidatesExistence::Rails2

Defined in:
lib/rails2.rb

Instance Method Summary collapse

Instance Method Details

#validates_existence_of(*attribute_names) ⇒ Object 



5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
 
# File 'lib/rails2.rb', line 5

def validates_existence_of(*attribute_names)
  options = attribute_names.extract_options!.symbolize_keys
  options[:message] ||= :existence
  options[:both]    = true unless options.key?(:both)

  validates_each(attribute_names, options) do |record, attribute, value|
    normalized  = attribute.to_s.sub(/_id$/, "").to_sym
    association = record.class.reflect_on_association(normalized)

    if association.nil? or !association.belongs_to?
      raise ArgumentError, "Cannot validate existence on #{normalized}, not a :belongs_to association"
    end

    target_class = nil

    # dealing with polymorphic belongs_to
    if association.options.has_key?(:foreign_type)
      foreign_type = record.send(association.options.fetch(:foreign_type))
      target_class = foreign_type.constantize unless foreign_type.nil?
    else
      target_class = association.klass
    end

    if target_class.nil? or !target_class.exists?(value)
      errors = [attribute]

      # add the error on both :relation and :relation_id
      if options[:both]
        errors.push(attribute.to_s.ends_with?("_id") ? normalized : association.primary_key_name)
      end

      errors.each do |error|
        record.errors.add(error, options[:message], :default => "does not exist")
      end
    end
  end
end