Within a method at runtime, is there a way to know if that method has been called via super
in a subclass? E.g.
module SuperDetector
def via_super?
# what goes here?
end
end
class Foo
include SuperDetector
def bar
via_super? ? 'super!' : 'nothing special'
end
end
class Fu < Foo
def bar
super
end
end
Foo.new.bar # => "nothing special"
Fu.new.bar # => "super!"
How could I write via_super?
, or, if necessary, via_super?(:bar)
?
The ultimate mix between my other, @mudasobwa's and @sawa's answers plus recursion support:
module SuperDetector
def self.included(clazz)
unless clazz.instance_methods.include?(:via_super?)
clazz.send(:define_method, :via_super?) do
first_caller_location = caller_locations.first
calling_method = first_caller_location.base_label
same_origin = ->(other_location) do
first_caller_location.lineno == other_location.lineno and
first_caller_location.absolute_path == other_location.absolute_path
end
location_changed = false
same_name_stack = caller_locations.take_while do |location|
should_take = location.base_label == calling_method and !location_changed
location_changed = !same_origin.call(location)
should_take
end
self.kind_of?(clazz) and !same_origin.call(same_name_stack.last)
end
end
end
end
The only case that wont work (AFAIK) is if you have indirect recursion in the base class, but I don't have ideas how to handle it with anything short of parsing the code.