Module: ActiveRecord::VirtualAttributes::VirtualDelegates::ClassMethods

Defined in:
lib/active_record/virtual_attributes/virtual_delegates.rb

Instance Method Summary collapse

Instance Method Details

#virtual_delegate(*methods) ⇒ Object

Definition



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# File 'lib/active_record/virtual_attributes/virtual_delegates.rb', line 22

def virtual_delegate(*methods)
  options = methods.extract_options!
  unless (to = options[:to])
    raise ArgumentError, 'Delegation needs an association. Supply an options hash with a :to key as the last argument (e.g. delegate :hello, to: :greeter).'
  end

  to = to.to_s
  if to.include?(".") && methods.size > 1
    raise ArgumentError, 'Delegation only supports specifying a method name when defining a single virtual method'
  end

  if to.count(".") > 1
    raise ArgumentError, 'Delegation needs a single association. Supply an option hash with a :to key with only 1 period (e.g. delegate :hello, to: "greeter.greeting")'
  end

  allow_nil = options[:allow_nil]
  default = options[:default]

  # put method entry per method name.
  # This better supports reloading of the class and changing the definitions
  methods.each do |method|
    method_prefix = virtual_delegate_name_prefix(options[:prefix], to)
    method_name = "#{method_prefix}#{method}"
    if to.include?(".") # to => "target.method"
      to, method = to.split(".")
      options[:to] = to
    end

    define_delegate(method_name, method, :to => to, :allow_nil => allow_nil, :default => default)

    self.virtual_delegates_to_define =
      virtual_delegates_to_define.merge(method_name => [method, options])
  end
end