Simple Ruby backtrace filtering

backtrace.rb

# Hook it up to your favorite testing framework:
#
# module MiniTest
#   def self.filter_backtrace(bt)
#     Backtrace.filter(bt)
#   end
# end
 
module Backtrace
  NOISE = Gem.path + $LOAD_PATH
 
  def self.filter(bt)
    return [] if bt.nil? || bt.empty?
 
    bt.select do |line|
      useful?(line)
    end
  end
 
  def self.useful?(line)
    NOISE.none? { |path| line.start_with?(path) }
  end
end