Issue #14626: Large refactoring of functions / parameters in the os module.

Many functions now support "dir_fd" and "follow_symlinks" parameters;
some also support accepting an open file descriptor in place of of a path
string.  Added os.support_* collections as LBYL helpers.  Removed many
functions only previously seen in 3.3 alpha releases (often starting with
"f" or "l", or ending with "at").  Originally suggested by Serhiy Storchaka;
implemented by Larry Hastings.

1 files changed, 85 insertions, 83 deletions

diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index d47c8d3..cc1120f 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -345,40 +345,36 @@ class StatAttributeTests(unittest.TestCase):
             return os.utime(file, ns=times)
         self._test_utime_ns(utime_ns)
 
-    requires_lutimes = unittest.skipUnless(hasattr(os, 'lutimes'),
-                            "os.lutimes required for this test.")
-    requires_futimes = unittest.skipUnless(hasattr(os, 'futimes'),
-                            "os.futimes required for this test.")
-
-    @requires_lutimes
+    requires_utime_dir_fd = unittest.skipUnless(
+                                os.utime in os.supports_dir_fd,
+                                "dir_fd support for utime required for this test.")
+    requires_utime_fd = unittest.skipUnless(
+                                os.utime in os.supports_fd,
+                                "fd support for utime required for this test.")
+    requires_utime_nofollow_symlinks = unittest.skipUnless(
+                                os.utime in os.supports_follow_symlinks,
+                                "follow_symlinks support for utime required for this test.")
+
+    @requires_utime_nofollow_symlinks
     def test_lutimes_ns(self):
         def lutimes_ns(file, times):
-            return os.lutimes(file, ns=times)
+            return os.utime(file, ns=times, follow_symlinks=False)
         self._test_utime_ns(lutimes_ns)
 
-    @requires_futimes
+    @requires_utime_fd
     def test_futimes_ns(self):
         def futimes_ns(file, times):
             with open(file, "wb") as f:
-                os.futimes(f.fileno(), ns=times)
+                os.utime(f.fileno(), ns=times)
         self._test_utime_ns(futimes_ns, test_dir=False)
 
     def _utime_invalid_arguments(self, name, arg):
-        with self.assertRaises(RuntimeError):
+        with self.assertRaises(ValueError):
             getattr(os, name)(arg, (5, 5), ns=(5, 5))
 
     def test_utime_invalid_arguments(self):
         self._utime_invalid_arguments('utime', self.fname)
 
-    @requires_lutimes
-    def test_lutimes_invalid_arguments(self):
-        self._utime_invalid_arguments('lutimes', self.fname)
-
-    @requires_futimes
-    def test_futimes_invalid_arguments(self):
-        with open(self.fname, "wb") as f:
-            self._utime_invalid_arguments('futimes', f.fileno())
-
 
     @unittest.skipUnless(stat_supports_subsecond,
                          "os.stat() doesn't has a subsecond resolution")
@@ -402,64 +398,46 @@ class StatAttributeTests(unittest.TestCase):
             os.utime(filename, (atime, mtime))
         self._test_utime_subsecond(set_time)
 
-    @requires_futimes
+    @requires_utime_fd
     def test_futimes_subsecond(self):
         def set_time(filename, atime, mtime):
             with open(filename, "wb") as f:
-                os.futimes(f.fileno(), (atime, mtime))
+                os.utime(f.fileno(), times=(atime, mtime))
         self._test_utime_subsecond(set_time)
 
-    @unittest.skipUnless(hasattr(os, 'futimens'),
-                         "os.futimens required for this test.")
+    @requires_utime_fd
     def test_futimens_subsecond(self):
         def set_time(filename, atime, mtime):
             with open(filename, "wb") as f:
-                asec, ansec = divmod(atime, 1.0)
-                asec = int(asec)
-                ansec = int(ansec * 1e9)
-                msec, mnsec = divmod(mtime, 1.0)
-                msec = int(msec)
-                mnsec = int(mnsec * 1e9)
-                os.futimens(f.fileno(),
-                           (asec, ansec),
-                           (msec, mnsec))
+                os.utime(f.fileno(), times=(atime, mtime))
         self._test_utime_subsecond(set_time)
 
-    @unittest.skipUnless(hasattr(os, 'futimesat'),
-                         "os.futimesat required for this test.")
+    @requires_utime_dir_fd
     def test_futimesat_subsecond(self):
         def set_time(filename, atime, mtime):
             dirname = os.path.dirname(filename)
             dirfd = os.open(dirname, os.O_RDONLY)
             try:
-                os.futimesat(dirfd, os.path.basename(filename),
-                             (atime, mtime))
+                os.utime(os.path.basename(filename), dir_fd=dirfd,
+                             times=(atime, mtime))
             finally:
                 os.close(dirfd)
         self._test_utime_subsecond(set_time)
 
-    @requires_lutimes
+    @requires_utime_nofollow_symlinks
     def test_lutimes_subsecond(self):
         def set_time(filename, atime, mtime):
-            os.lutimes(filename, (atime, mtime))
+            os.utime(filename, (atime, mtime), follow_symlinks=False)
         self._test_utime_subsecond(set_time)
 
-    @unittest.skipUnless(hasattr(os, 'utimensat'),
-                         "os.utimensat required for this test.")
+    @requires_utime_dir_fd
     def test_utimensat_subsecond(self):
         def set_time(filename, atime, mtime):
             dirname = os.path.dirname(filename)
             dirfd = os.open(dirname, os.O_RDONLY)
             try:
-                asec, ansec = divmod(atime, 1.0)
-                asec = int(asec)
-                ansec = int(ansec * 1e9)
-                msec, mnsec = divmod(mtime, 1.0)
-                msec = int(msec)
-                mnsec = int(mnsec * 1e9)
-                os.utimensat(dirfd, os.path.basename(filename),
-                             (asec, ansec),
-                             (msec, mnsec))
+                os.utime(os.path.basename(filename), dir_fd=dirfd,
+                             times=(atime, mtime))
             finally:
                 os.close(dirfd)
         self._test_utime_subsecond(set_time)
@@ -782,8 +760,10 @@ class FwalkTests(WalkTests):
             for root, dirs, files, rootfd in os.fwalk(*args):
                 # check that the FD is valid
                 os.fstat(rootfd)
-                # check that flistdir() returns consistent information
-                self.assertEqual(set(os.flistdir(rootfd)), set(dirs) | set(files))
+                # redundant check
+                os.stat(rootfd)
+                # check that listdir() returns consistent information
+                self.assertEqual(set(os.listdir(rootfd)), set(dirs) | set(files))
 
     def test_fd_leak(self):
         # Since we're opening a lot of FDs, we must be careful to avoid leaks:
@@ -802,13 +782,10 @@ class FwalkTests(WalkTests):
         # cleanup
         for root, dirs, files, rootfd in os.fwalk(support.TESTFN, topdown=False):
             for name in files:
-                os.unlinkat(rootfd, name)
+                os.unlink(name, dir_fd=rootfd)
             for name in dirs:
-                st = os.fstatat(rootfd, name, os.AT_SYMLINK_NOFOLLOW)
-                if stat.S_ISDIR(st.st_mode):
-                    os.unlinkat(rootfd, name, os.AT_REMOVEDIR)
-                else:
-                    os.unlinkat(rootfd, name)
+                st = os.stat(name, dir_fd=rootfd, follow_symlinks=False)
+                os.unlink(name, dir_fd=rootfd, rmdir=stat.S_ISDIR(st.st_mode))
         os.rmdir(support.TESTFN)
 
 
@@ -1262,6 +1239,13 @@ if sys.platform != 'win32':
             expected = self.unicodefn
             found = set(os.listdir(self.dir))
             self.assertEqual(found, expected)
+            # test listdir without arguments
+            current_directory = os.getcwd()
+            try:
+                os.chdir(os.sep)
+                self.assertEqual(set(os.listdir()), set(os.listdir(os.sep)))
+            finally:
+                os.chdir(current_directory)
 
         def test_open(self):
             for fn in self.unicodefn:
@@ -1846,79 +1830,97 @@ class TestSendfile(unittest.TestCase):
                         raise
 
 
-@support.skip_unless_xattr
+def supports_extended_attributes():
+    if not hasattr(os, "setxattr"):
+        return False
+    try:
+        with open(support.TESTFN, "wb") as fp:
+            try:
+                os.setxattr(fp.fileno(), b"user.test", b"")
+            except OSError:
+                return False
+    finally:
+        support.unlink(support.TESTFN)
+    # Kernels < 2.6.39 don't respect setxattr flags.
+    kernel_version = platform.release()
+    m = re.match("2.6.(\d{1,2})", kernel_version)
+    return m is None or int(m.group(1)) >= 39
+
+
+@unittest.skipUnless(supports_extended_attributes(),
+                     "no non-broken extended attribute support")
 class ExtendedAttributeTests(unittest.TestCase):
 
     def tearDown(self):
         support.unlink(support.TESTFN)
 
-    def _check_xattrs_str(self, s, getxattr, setxattr, removexattr, listxattr):
+    def _check_xattrs_str(self, s, getxattr, setxattr, removexattr, listxattr, **kwargs):
         fn = support.TESTFN
         open(fn, "wb").close()
         with self.assertRaises(OSError) as cm:
-            getxattr(fn, s("user.test"))
+            getxattr(fn, s("user.test"), **kwargs)
         self.assertEqual(cm.exception.errno, errno.ENODATA)
         init_xattr = listxattr(fn)
         self.assertIsInstance(init_xattr, list)
-        setxattr(fn, s("user.test"), b"")
+        setxattr(fn, s("user.test"), b"", **kwargs)
         xattr = set(init_xattr)
         xattr.add("user.test")
         self.assertEqual(set(listxattr(fn)), xattr)
-        self.assertEqual(getxattr(fn, b"user.test"), b"")
-        setxattr(fn, s("user.test"), b"hello", os.XATTR_REPLACE)
-        self.assertEqual(getxattr(fn, b"user.test"), b"hello")
+        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"")
+        setxattr(fn, s("user.test"), b"hello", os.XATTR_REPLACE, **kwargs)
+        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"hello")
         with self.assertRaises(OSError) as cm:
-            setxattr(fn, s("user.test"), b"bye", os.XATTR_CREATE)
+            setxattr(fn, s("user.test"), b"bye", os.XATTR_CREATE, **kwargs)
         self.assertEqual(cm.exception.errno, errno.EEXIST)
         with self.assertRaises(OSError) as cm:
-            setxattr(fn, s("user.test2"), b"bye", os.XATTR_REPLACE)
+            setxattr(fn, s("user.test2"), b"bye", os.XATTR_REPLACE, **kwargs)
         self.assertEqual(cm.exception.errno, errno.ENODATA)
-        setxattr(fn, s("user.test2"), b"foo", os.XATTR_CREATE)
+        setxattr(fn, s("user.test2"), b"foo", os.XATTR_CREATE, **kwargs)
         xattr.add("user.test2")
         self.assertEqual(set(listxattr(fn)), xattr)
-        removexattr(fn, s("user.test"))
+        removexattr(fn, s("user.test"), **kwargs)
         with self.assertRaises(OSError) as cm:
-            getxattr(fn, s("user.test"))
+            getxattr(fn, s("user.test"), **kwargs)
         self.assertEqual(cm.exception.errno, errno.ENODATA)
         xattr.remove("user.test")
         self.assertEqual(set(listxattr(fn)), xattr)
-        self.assertEqual(getxattr(fn, s("user.test2")), b"foo")
-        setxattr(fn, s("user.test"), b"a"*1024)
-        self.assertEqual(getxattr(fn, s("user.test")), b"a"*1024)
-        removexattr(fn, s("user.test"))
+        self.assertEqual(getxattr(fn, s("user.test2"), **kwargs), b"foo")
+        setxattr(fn, s("user.test"), b"a"*1024, **kwargs)
+        self.assertEqual(getxattr(fn, s("user.test"), **kwargs), b"a"*1024)
+        removexattr(fn, s("user.test"), **kwargs)
         many = sorted("user.test{}".format(i) for i in range(100))
         for thing in many:
-            setxattr(fn, thing, b"x")
+            setxattr(fn, thing, b"x", **kwargs)
         self.assertEqual(set(listxattr(fn)), set(init_xattr) | set(many))
 
-    def _check_xattrs(self, *args):
+    def _check_xattrs(self, *args, **kwargs):
         def make_bytes(s):
             return bytes(s, "ascii")
-        self._check_xattrs_str(str, *args)
+        self._check_xattrs_str(str, *args, **kwargs)
         support.unlink(support.TESTFN)
-        self._check_xattrs_str(make_bytes, *args)
+        self._check_xattrs_str(make_bytes, *args, **kwargs)
 
     def test_simple(self):
         self._check_xattrs(os.getxattr, os.setxattr, os.removexattr,
                            os.listxattr)
 
     def test_lpath(self):
-        self._check_xattrs(os.lgetxattr, os.lsetxattr, os.lremovexattr,
-                           os.llistxattr)
+        self._check_xattrs(os.getxattr, os.setxattr, os.removexattr,
+                           os.listxattr, follow_symlinks=False)
 
     def test_fds(self):
         def getxattr(path, *args):
             with open(path, "rb") as fp:
-                return os.fgetxattr(fp.fileno(), *args)
+                return os.getxattr(fp.fileno(), *args)
         def setxattr(path, *args):
             with open(path, "wb") as fp:
-                os.fsetxattr(fp.fileno(), *args)
+                os.setxattr(fp.fileno(), *args)
         def removexattr(path, *args):
             with open(path, "wb") as fp:
-                os.fremovexattr(fp.fileno(), *args)
+                os.removexattr(fp.fileno(), *args)
         def listxattr(path, *args):
             with open(path, "rb") as fp:
-                return os.flistxattr(fp.fileno(), *args)
+                return os.listxattr(fp.fileno(), *args)
         self._check_xattrs(getxattr, setxattr, removexattr, listxattr)