bpo-39901: Move pathlib.Path.owner() and group() implementations into the path accessor

Lib/pathlib.py

@@ -447,6 +447,20 @@ def symlink(a, b, target_is_directory):
  def readlink(self, path):
  return os.readlink(path)
 
+ def owner(self, path):
+ try:
+ import pwd
+ return pwd.getpwuid(self.stat(path).st_uid).pw_name
+ except ImportError:
+ raise NotImplementedError("Path.owner() is unsupported on this system")
+
+ def group(self, path):
+ try:
+ import grp
+ return grp.getgrgid(self.stat(path).st_gid).gr_name
+ except ImportError:
+ raise NotImplementedError("Path.group() is unsupported on this system")
+
 
 _normal_accessor = _NormalAccessor()
 
@@ -1209,15 +1223,13 @@ def owner(self):
  """
  Return the login name of the file owner.
  """
- import pwd
- return pwd.getpwuid(self.stat().st_uid).pw_name
+ return self._accessor.owner(self)
 
  def group(self):
  """
  Return the group name of the file gid.
  """
- import grp
- return grp.getgrgid(self.stat().st_gid).gr_name
+ return self._accessor.group(self)
 
  def open(self, mode='r', buffering=-1, encoding=None,
  errors=None, newline=None):
@@ -1575,11 +1587,5 @@ class WindowsPath(Path, PureWindowsPath):
  """
  __slots__ = ()
 
- def owner(self):
- raise NotImplementedError("Path.owner() is unsupported on this system")
-
- def group(self):
- raise NotImplementedError("Path.group() is unsupported on this system")
-
  def is_mount(self):
  raise NotImplementedError("Path.is_mount() is unsupported on this system")