class Sprockets::SassImporter

compile.
This custom importer that tracks all imported filenames during

def find(*args) 

def find(*args)
  engine = super
  if engine && (filename = engine.options[:filename])
    @imported_filenames << filename
  end
  engine
end

def find_relative(*args) 

def find_relative(*args)
  engine = super
  if engine && (filename = engine.options[:filename])
    @imported_filenames << filename
  end
  engine
end

def initialize(*args) 

def initialize(*args)
  @imported_filenames = []
  super
end