class Sass::Plugin::Compiler

def remove_redundant_directories(directories)
  dedupped = []
  directories.each do |new_directory|
    # no need to add a directory that is already watched.
    next if dedupped.any? do |existing_directory|
      child_of_directory?(existing_directory, new_directory)
    end
    # get rid of any sub directories of this new directory
    dedupped.reject! do |existing_directory|
      child_of_directory?(new_directory, existing_directory)
    end
    dedupped << new_directory
  end
  dedupped
end