module Sprockets::PathDigestUtils

def file_digest(path)

Returns String digest bytes or nil.

path - String filename or directory path.

Internal: Compute digest for path. 
def file_digest(path)
  if stat = self.stat(path)
    self.stat_digest(path, stat)
  end
end

def files_digest(paths)

Returns String digest bytes.

paths - Array of filename or directory paths.

Internal: Compute digest for a set of paths. 
def files_digest(paths)
  self.digest(paths.map { |path| self.file_digest(path) })
end

def stat_digest(path, stat)

Returns String digest bytes.

stat - File::Stat
path - String filename

Internal: Compute digest for file stat. 
def stat_digest(path, stat)
  if stat.directory?
    # If its a directive, digest the list of filenames
    digest_class.digest(self.entries(path).join(','))
  elsif stat.file?
    # If its a file, digest the contents
    digest_class.file(path.to_s).digest
  else
    raise TypeError, "stat was not a directory or file: #{stat.ftype}"
  end
end