move root checks to test.support

Author: kulikjak

Lib/test/support/__init__.py

@@ -71,7 +71,7 @@
     "BrokenIter",
     "in_systemd_nspawn_sync_suppressed",
     "run_no_yield_async_fn", "run_yielding_async_fn", "async_yield",
-    "reset_code", "on_github_actions"
+    "reset_code", "on_github_actions", "requires_root", "requires_non_root",
     ]
 
 
@@ -3317,3 +3317,8 @@ def control_characters_c0() -> list[str]:
     C0 control characters defined as the byte range 0x00-0x1F, and 0x7F.
     """
     return [chr(c) for c in range(0x00, 0x20)] + ["\x7F"]
+
+
+_ROOT_IN_POSIX = hasattr(os, 'geteuid') and os.geteuid() == 0
+requires_root = unittest.skipUnless(_ROOT_IN_POSIX, "test needs root privilege")
+requires_non_root = unittest.skipIf(_ROOT_IN_POSIX, "test needs non-root account")

Lib/test/test_mailbox.py

@@ -11,6 +11,7 @@
 from test.support import import_helper, warnings_helper
 from test.support import os_helper
 from test.support import refleak_helper
+from test.support import requires_root
 from test.support import socket_helper
 import unittest
 import textwrap
@@ -1086,6 +1087,7 @@ def test_permissions_after_flush(self):
 
         self.assertEqual(os.stat(self._path).st_mode, mode)
 
+    @requires_root
     @unittest.skipUnless(hasattr(os, 'chown'), 'requires os.chown')
     def test_ownership_after_flush(self):
         # See issue gh-117467
@@ -1108,10 +1110,7 @@ def test_ownership_after_flush(self):
         else:
             self.skipTest("test needs more than one group")
 
-        try:
-            os.chown(self._path, other_uid, other_gid)
-        except OSError:
-            self.skipTest('test needs root privilege')
+        os.chown(self._path, other_uid, other_gid)
         # Change permissions as in test_permissions_after_flush.
         mode = st.st_mode | 0o666
         os.chmod(self._path, mode)

Lib/test/test_os/test_os.py

@@ -33,6 +33,8 @@
 from test.support import os_helper
 from test.support import socket_helper
 from test.support import infinite_recursion
+from test.support import requires_root
+from test.support import requires_non_root
 from test.support import warnings_helper
 from platform import win32_is_iot
 from .utils import create_file
@@ -67,10 +69,6 @@
 from test.support.os_helper import FakePath
 
 
-root_in_posix = False
-if hasattr(os, 'geteuid'):
-    root_in_posix = (os.geteuid() == 0)
-
 # Detect whether we're on a Linux system that uses the (now outdated
 # and unmaintained) linuxthreads threading library.  There's an issue
 # when combining linuxthreads with a failed execv call: see
@@ -2257,8 +2255,8 @@ def test_chown_gid(self):
         gid = os.stat(os_helper.TESTFN).st_gid
         self.assertEqual(gid, gid_2)
 
-    @unittest.skipUnless(root_in_posix and len(all_users) > 1,
-                         "test needs root privilege and more than one user")
+    @requires_root
+    @unittest.skipUnless(len(all_users) > 1, "test needs more than one user")
     def test_chown_with_root(self):
         uid_1, uid_2 = all_users[:2]
         gid = os.stat(os_helper.TESTFN).st_gid
@@ -2269,8 +2267,8 @@ def test_chown_with_root(self):
         uid = os.stat(os_helper.TESTFN).st_uid
         self.assertEqual(uid, uid_2)
 
-    @unittest.skipUnless(not root_in_posix and len(all_users) > 1,
-                         "test needs non-root account and more than one user")
+    @requires_non_root
+    @unittest.skipUnless(len(all_users) > 1, "test needs and more than one user")
     def test_chown_without_permission(self):
         uid_1, uid_2 = all_users[:2]
         gid = os.stat(os_helper.TESTFN).st_gid

Lib/test/test_pathlib/test_pathlib.py

@@ -20,6 +20,7 @@
 from test.support import is_emscripten, is_wasi, is_wasm32
 from test.support import infinite_recursion
 from test.support import os_helper
+from test.support import requires_root
 from test.support.os_helper import TESTFN, FS_NONASCII, FakePath
 try:
     import fcntl
@@ -35,11 +36,6 @@
     posix = None
 
 
-root_in_posix = False
-if hasattr(os, 'geteuid'):
-    root_in_posix = (os.geteuid() == 0)
-
-
 def patch_replace(old_test):
     def new_replace(self, target):
         raise OSError(errno.EXDEV, "Cross-device link", self, target)
@@ -1554,7 +1550,7 @@ def raiser(*args, **kwargs):
             self.assertRaises(FileNotFoundError, source.copy, target)
 
     @unittest.skipIf(sys.platform == "win32" or sys.platform == "wasi", "directories are always readable on Windows and WASI")
-    @unittest.skipIf(root_in_posix, "test fails with root privilege")
+    @requires_root
     def test_copy_dir_no_read_permission(self):
         base = self.cls(self.base)
         source = base / 'dirE'
@@ -2027,7 +2023,7 @@ def test_owner(self):
         self.assertEqual(expected_name, p.owner())
 
     @unittest.skipUnless(pwd, "the pwd module is needed for this test")
-    @unittest.skipUnless(root_in_posix, "test needs root privilege")
+    @requires_root
     def test_owner_no_follow_symlinks(self):
         all_users = [u.pw_uid for u in pwd.getpwall()]
         if len(all_users) < 2:
@@ -2062,7 +2058,7 @@ def test_group(self):
         self.assertEqual(expected_name, p.group())
 
     @unittest.skipUnless(grp, "the grp module is needed for this test")
-    @unittest.skipUnless(root_in_posix, "test needs root privilege")
+    @requires_root
     def test_group_no_follow_symlinks(self):
         all_groups = [g.gr_gid for g in grp.getgrall()]
         if len(all_groups) < 2:
@@ -3216,15 +3212,14 @@ def test_touch_mode(self):
         st = os.stat(self.parser.join(self.base, 'masked_new_file'))
         self.assertEqual(stat.S_IMODE(st.st_mode), 0o750)
 
+    @unittest.skipUnless(pwd, "the pwd module is needed for this test")
     @unittest.skipUnless(hasattr(pwd, 'getpwall'),
                          'pwd module does not expose getpwall()')
     @unittest.skipIf(sys.platform == "vxworks",
                      "no home directory on VxWorks")
     @needs_posix
     def test_expanduser_posix(self):
         P = self.cls
-        import_helper.import_module('pwd')
-        import pwd
         pwdent = pwd.getpwuid(os.getuid())
         username = pwdent.pw_name
         userhome = pwdent.pw_dir.rstrip('/') or '/'