text: # Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
  # Spack Project Developers. See the top-level COPYRIGHT file for details.
  #
  # SPDX-License-Identifier: (Apache-2.0 OR MIT)
  
  import os
  import re
  from itertools import product
  
  from spack.util.executable import which
  
  # Supported archive extensions.
  PRE_EXTS   = ["tar", "TAR"]
  EXTS       = ["gz", "bz2", "xz", "Z"]
  NOTAR_EXTS = ["zip", "tgz", "tbz", "tbz2", "txz"]
  
  # Add PRE_EXTS and EXTS last so that .tar.gz is matched *before* .tar or .gz
  ALLOWED_ARCHIVE_TYPES = [".".join(ext) for ext in product(
      PRE_EXTS, EXTS)] + PRE_EXTS + EXTS + NOTAR_EXTS
  
  
  def allowed_archive(path):
      return any(path.endswith(t) for t in ALLOWED_ARCHIVE_TYPES)
  
  
  def _gunzip(archive_file):
      """Like gunzip, but extracts in the current working directory
      instead of in-place.
  
      Args:
          archive_file (str): absolute path of the file to be decompressed
      """
      import gzip
      decompressed_file = os.path.basename(archive_file.strip('.gz'))
      working_dir = os.getcwd()
      destination_abspath = os.path.join(working_dir, decompressed_file)
      with gzip.open(archive_file, "rb") as f_in:
          with open(destination_abspath, "wb") as f_out:
              f_out.write(f_in.read())
  
  
  def decompressor_for(path, extension=None):
      """Get the appropriate decompressor for a path."""
      if ((extension and re.match(r'\.?zip$', extension)) or
              path.endswith('.zip')):
          unzip = which('unzip', required=True)
          unzip.add_default_arg('-q')
          return unzip
      if extension and re.match(r'gz', extension):
          return _gunzip
      if extension and re.match(r'bz2', extension):
          bunzip2 = which('bunzip2', required=True)
          return bunzip2
      tar = which('tar', required=True)
      tar.add_default_arg('-oxf')
      return tar
  
  
  def strip_extension(path):
      """Get the part of a path that does not include its compressed
         type extension."""
      for type in ALLOWED_ARCHIVE_TYPES:
          suffix = r'\.%s$' % type
          if re.search(suffix, path):
              return re.sub(suffix, "", path)
      return path
  
  
  def extension(path):
      """Get the archive extension for a path."""
      if path is None:
          raise ValueError("Can't call extension() on None")
  
      # Strip sourceforge suffix.
      if re.search(r'((?:sourceforge.net|sf.net)/.*)/download$', path):
          path = os.path.dirname(path)
  
      for t in ALLOWED_ARCHIVE_TYPES:
          suffix = r'\.%s$' % t
          if re.search(suffix, path):
              return t
      return None
  