Issue #5411: Added support for the "xztar" format in the shutil module.

Doc/library/shutil.rst

@@ -469,7 +469,8 @@ provided.  They rely on the :mod:`zipfile` and :mod:`tarfile` modules.
 
    *base_name* is the name of the file to create, including the path, minus
    any format-specific extension. *format* is the archive format: one of
-   "zip", "tar", "bztar" (if the :mod:`bz2` module is available) or "gztar".
+   "zip", "tar", "bztar" (if the :mod:`bz2` module is available), "xztar"
+   (if the :mod:`lzma` module is available) or "gztar".
 
    *root_dir* is a directory that will be the root directory of the
    archive; for example, we typically chdir into *root_dir* before creating the
@@ -487,6 +488,9 @@ provided.  They rely on the :mod:`zipfile` and :mod:`tarfile` modules.
    *logger* must be an object compatible with :pep:`282`, usually an instance of
    :class:`logging.Logger`.
 
+   .. versionchanged:: 3.4
+   Added support for the *xztar* format.
+
 
 .. function:: get_archive_formats()
 
@@ -497,6 +501,7 @@ provided.  They rely on the :mod:`zipfile` and :mod:`tarfile` modules.
 
    - *gztar*: gzip'ed tar-file
    - *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available.)
+   - *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available.)
    - *tar*: uncompressed tar file
    - *zip*: ZIP file
 
@@ -567,6 +572,7 @@ provided.  They rely on the :mod:`zipfile` and :mod:`tarfile` modules.
 
    - *gztar*: gzip'ed tar-file
    - *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available.)
+   - *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available.)
    - *tar*: uncompressed tar file
    - *zip*: ZIP file
 

Lib/shutil.py

@@ -20,6 +20,13 @@ try:
 except ImportError:
     _BZ2_SUPPORTED = False
 
+try:
+    import lzma
+    del lzma
+    _LZMA_SUPPORTED = True
+except ImportError:
+    _LZMA_SUPPORTED = False
+
 try:
     from pwd import getpwnam
 except ImportError:
@@ -580,14 +587,14 @@ def _make_tarball(base_name, base_dir, compress="gzip", verbose=0, dry_run=0,
     """Create a (possibly compressed) tar file from all the files under
     'base_dir'.
 
-    'compress' must be "gzip" (the default), "bzip2", or None.
+    'compress' must be "gzip" (the default), "bzip2", "xz", or None.
 
     'owner' and 'group' can be used to define an owner and a group for the
     archive that is being built. If not provided, the current owner and group
     will be used.
 
     The output tar file will be named 'base_name' +  ".tar", possibly plus
-    the appropriate compression extension (".gz", or ".bz2").
+    the appropriate compression extension (".gz", ".bz2", or ".xz").
 
     Returns the output filename.
     """
@@ -598,6 +605,10 @@ def _make_tarball(base_name, base_dir, compress="gzip", verbose=0, dry_run=0,
         tar_compression['bzip2'] = 'bz2'
         compress_ext['bzip2'] = '.bz2'
 
+    if _LZMA_SUPPORTED:
+        tar_compression['xz'] = 'xz'
+        compress_ext['xz'] = '.xz'
+
     # flags for compression program, each element of list will be an argument
     if compress is not None and compress not in compress_ext:
         raise ValueError("bad value for 'compress', or compression format not "
@@ -684,6 +695,10 @@ if _BZ2_SUPPORTED:
     _ARCHIVE_FORMATS['bztar'] = (_make_tarball, [('compress', 'bzip2')],
                                 "bzip2'ed tar-file")
 
+if _LZMA_SUPPORTED:
+    _ARCHIVE_FORMATS['xztar'] = (_make_tarball, [('compress', 'xz')],
+                                "xz'ed tar-file")
+
 def get_archive_formats():
     """Returns a list of supported formats for archiving and unarchiving.
 
@@ -872,7 +887,7 @@ def _unpack_zipfile(filename, extract_dir):
         zip.close()
 
 def _unpack_tarfile(filename, extract_dir):
-    """Unpack tar/tar.gz/tar.bz2 `filename` to `extract_dir`
+    """Unpack tar/tar.gz/tar.bz2/tar.xz `filename` to `extract_dir`
     """
     try:
         tarobj = tarfile.open(filename)
@@ -891,9 +906,13 @@ _UNPACK_FORMATS = {
     }
 
 if _BZ2_SUPPORTED:
-    _UNPACK_FORMATS['bztar'] = (['.bz2'], _unpack_tarfile, [],
+    _UNPACK_FORMATS['bztar'] = (['.tar.bz2', '.tbz2'], _unpack_tarfile, [],
                                 "bzip2'ed tar-file")
 
+if _LZMA_SUPPORTED:
+    _UNPACK_FORMATS['xztar'] = (['.tar.xz', '.txz'], _unpack_tarfile, [],
+                                "xz'ed tar-file")
+
 def _find_unpack_format(filename):
     for name, info in _UNPACK_FORMATS.items():
         for extension in info[0]:

Lib/test/test_shutil.py

@@ -32,6 +32,12 @@ try:
 except ImportError:
     BZ2_SUPPORTED = False
 
+try:
+    import lzma
+    LZMA_SUPPORTED = True
+except ImportError:
+    LZMA_SUPPORTED = False
+
 TESTFN2 = TESTFN + "2"
 
 try:
@@ -1156,6 +1162,8 @@ class TestShutil(unittest.TestCase):
         formats = ['tar', 'gztar', 'zip']
         if BZ2_SUPPORTED:
             formats.append('bztar')
+        if LZMA_SUPPORTED:
+            formats.append('xztar')
 
         for format in formats:
             tmpdir = self.mkdtemp()

Misc/NEWS

@@ -112,6 +112,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #5411: Added support for the "xztar" format in the shutil module.
+
 - Issue #21975: Fixed crash when using uninitialized sqlite3.Row (in particular
   when unpickling pickled sqlite3.Row).  sqlite3.Row is now initialized in the
   __new__() method.