Ruby File.combine_relative_paths

gistfile1.txt

# Note: there is also  URI::join(base_path, relative_path) for URI paths
#

File.class_eval do
  # combines "some/path/here" and "../there/something?asdf=qwerty" to be:
  #      "/some/path/there/something?asdf=qwerty"
  #
  # usage: File.combine_relative_path(base_path, relative_path)
  #
  def self.combine_relative_paths(base_path, relative_path)
    base_path_parts = base_path.split("/")
    relative_path_parts = relative_path.split("/")
    doubledots_count = relative_path.scan(/\.\.\//).size
    doubledots_count.times do
      # remove base path parts from the back and relative parts from the front
      base_path_parts.pop 
      relative_path_parts.shift
    end
    (base_path_parts + relative_path_parts).join("/")
  end

end