List of defined super methods for a certain class method in ruby

Question

I am working on a system with a some complex class/mixin hierarchy. As there are several numerous layers scattered over many different files, I want to quickly see what the chain of super calls is for a given method.

For example

module AAA
  def to_s
    "AAA " + super()
  end
end

module BBB
  def to_s
    "BBB " + super()
  end
end

class MyArray < Array
  include AAA
  include BBB

  def to_s
    "MyArray " + super()
  end
end

> MyArray.new.to_s
=> "MyArray BBB AAA []"
> method_supers(MyArray,:to_s)
=> ["MyArray#to_s", "BBB#to_s", "AAA#to_s", "Array#to_s", ...]

Answer 1

Perhaps something like this?

class A
  def foo; p :A; end
end

module B
  def foo; p :B; super; end
end

module C; end

class D < A
  include B, C
  def foo; p :D; super; end
end

p D.ancestors.keep_if { |c| c.instance_methods.include? :foo }  # [D, B, A]

If that seems right, you could amend this function accordingly:

def Object.super_methods(method)
  ancestors.keep_if { |c| c.instance_methods.include? method }
end

p D.super_methods(:foo)  # [D, B, A]

Answer 2

def method_supers(child_class,method_name)
  ancestry = child_class.ancestors

  methods = ancestry.map do |ancestor|
    begin
      ancestor.instance_method(method_name)
    rescue
      nil
    end
  end

  methods.reject!(&:nil?)

  methods.map {|m| m.owner.name + "#" + m.name.to_s}
end