Not create tag for nested method

[sphynx79]

In some case in Ruby i use nested method same this:

# a.rb
class A
  def testInstanceA
    def testSubInstance
    end
  end

  def self.testClassA
  end
end

universal ctags make tag also for my nested method, but ripper-tgas no.
ctags --languages=ruby

A	a.rb	/^class A$/;"	class	line:8	language:Ruby
B	b.rb	/^class B$/;"	class	line:8	language:Ruby
testClassA	a.rb	/^  def self.testClassA$/;"	singletonMethod	line:14	language:Ruby	class:A
testClassB	b.rb	/^  def self.testClassB$/;"	singletonMethod	line:12	language:Ruby	class:B
testInstanceA	a.rb	/^  def testInstanceA$/;"	method	line:9	language:Ruby	class:A
testInstanceB	b.rb	/^  def testInstanceB$/;"	method	line:9	language:Ruby	class:B
testSubInstance	a.rb	/^    def testSubInstance$/;"	method	line:10	language:Ruby	method:A.testInstanceA

ripper-tags -R

A	a.rb	/^class A$/;"	c
B	b.rb	/^class B$/;"	c
testClassA	a.rb	/^  def self.testClassA$/;"	F	class:A
testClassB	b.rb	/^  def self.testClassB$/;"	F	class:B
testInstanceA	a.rb	/^  def testInstanceA$/;"	f	class:A
testInstanceB	b.rb	/^  def testInstanceB$/;"	f	class:B