cpython/Lib/test/test_pathlib.py

import collections.abc
import io
import os
import sys
import errno
import pathlib
import pickle
import posixpath
import socket
import stat
import tempfile
import unittest
from unittest import mock

from test.support import import_helper
from test.support import set_recursion_limit
from test.support import is_emscripten, is_wasi
from test.support import os_helper
from test.support.os_helper import TESTFN, FakePath

try:
    import grp, pwd
except ImportError:
    grp = pwd = None


class UnsupportedOperationTest(unittest.TestCase):
    def test_is_notimplemented(self):
        self.assertTrue(issubclass(pathlib.UnsupportedOperation, NotImplementedError))
        self.assertTrue(isinstance(pathlib.UnsupportedOperation(), NotImplementedError))


# Make sure any symbolic links in the base test path are resolved.
BASE = os.path.realpath(TESTFN)
join = lambda *x: os.path.join(BASE, *x)
rel_join = lambda *x: os.path.join(TESTFN, *x)

only_nt = unittest.skipIf(os.name != 'nt',
                          'test requires a Windows-compatible system')
only_posix = unittest.skipIf(os.name == 'nt',
                             'test requires a POSIX-compatible system')


#
# Tests for the pure classes.
#

class PurePathTest(unittest.TestCase):
    cls = pathlib.PurePath

    # Keys are canonical paths, values are list of tuples of arguments
    # supposed to produce equal paths.
    equivalences = {
        'a/b': [
            ('a', 'b'), ('a/', 'b'), ('a', 'b/'), ('a/', 'b/'),
            ('a/b/',), ('a//b',), ('a//b//',),
            # Empty components get removed.
            ('', 'a', 'b'), ('a', '', 'b'), ('a', 'b', ''),
            ],
        '/b/c/d': [
            ('a', '/b/c', 'd'), ('/a', '/b/c', 'd'),
            # Empty components get removed.
            ('/', 'b', '', 'c/d'), ('/', '', 'b/c/d'), ('', '/b/c/d'),
            ],
    }

    def setUp(self):
        p = self.cls('a')
        self.flavour = p._flavour
        self.sep = self.flavour.sep
        self.altsep = self.flavour.altsep

    def test_constructor_common(self):
        P = self.cls
        p = P('a')
        self.assertIsInstance(p, P)
        P('a', 'b', 'c')
        P('/a', 'b', 'c')
        P('a/b/c')
        P('/a/b/c')
        P(FakePath("a/b/c"))
        self.assertEqual(P(P('a')), P('a'))
        self.assertEqual(P(P('a'), 'b'), P('a/b'))
        self.assertEqual(P(P('a'), P('b')), P('a/b'))
        self.assertEqual(P(P('a'), P('b'), P('c')), P(FakePath("a/b/c")))
        self.assertEqual(P(P('./a:b')), P('./a:b'))

    def test_concrete_class(self):
        if self.cls is pathlib.PurePath:
            expected = pathlib.PureWindowsPath if os.name == 'nt' else pathlib.PurePosixPath
        else:
            expected = self.cls
        p = self.cls('a')
        self.assertIs(type(p), expected)

    def test_different_flavours_unequal(self):
        p = self.cls('a')
        if p._flavour is posixpath:
            q = pathlib.PureWindowsPath('a')
        else:
            q = pathlib.PurePosixPath('a')
        self.assertNotEqual(p, q)

    def test_different_flavours_unordered(self):
        p = self.cls('a')
        if p._flavour is posixpath:
            q = pathlib.PureWindowsPath('a')
        else:
            q = pathlib.PurePosixPath('a')
        with self.assertRaises(TypeError):
            p < q
        with self.assertRaises(TypeError):
            p <= q
        with self.assertRaises(TypeError):
            p > q
        with self.assertRaises(TypeError):
            p >= q

    def test_bytes(self):
        P = self.cls
        message = (r"argument should be a str or an os\.PathLike object "
                   r"where __fspath__ returns a str, not 'bytes'")
        with self.assertRaisesRegex(TypeError, message):
            P(b'a')
        with self.assertRaisesRegex(TypeError, message):
            P(b'a', 'b')
        with self.assertRaisesRegex(TypeError, message):
            P('a', b'b')
        with self.assertRaises(TypeError):
            P('a').joinpath(b'b')
        with self.assertRaises(TypeError):
            P('a') / b'b'
        with self.assertRaises(TypeError):
            b'a' / P('b')
        with self.assertRaises(TypeError):
            P('a').match(b'b')
        with self.assertRaises(TypeError):
            P('a').relative_to(b'b')
        with self.assertRaises(TypeError):
            P('a').with_name(b'b')
        with self.assertRaises(TypeError):
            P('a').with_stem(b'b')
        with self.assertRaises(TypeError):
            P('a').with_suffix(b'b')

    def _check_str_subclass(self, *args):
        # Issue #21127: it should be possible to construct a PurePath object
        # from a str subclass instance, and it then gets converted to
        # a pure str object.
        class StrSubclass(str):
            pass
        P = self.cls
        p = P(*(StrSubclass(x) for x in args))
        self.assertEqual(p, P(*args))
        for part in p.parts:
            self.assertIs(type(part), str)

    def test_str_subclass_common(self):
        self._check_str_subclass('')
        self._check_str_subclass('.')
        self._check_str_subclass('a')
        self._check_str_subclass('a/b.txt')
        self._check_str_subclass('/a/b.txt')

    def test_with_segments_common(self):
        class P(self.cls):
            def __init__(self, *pathsegments, session_id):
                super().__init__(*pathsegments)
                self.session_id = session_id

            def with_segments(self, *pathsegments):
                return type(self)(*pathsegments, session_id=self.session_id)
        p = P('foo', 'bar', session_id=42)
        self.assertEqual(42, (p / 'foo').session_id)
        self.assertEqual(42, ('foo' / p).session_id)
        self.assertEqual(42, p.joinpath('foo').session_id)
        self.assertEqual(42, p.with_name('foo').session_id)
        self.assertEqual(42, p.with_stem('foo').session_id)
        self.assertEqual(42, p.with_suffix('.foo').session_id)
        self.assertEqual(42, p.with_segments('foo').session_id)
        self.assertEqual(42, p.relative_to('foo').session_id)
        self.assertEqual(42, p.parent.session_id)
        for parent in p.parents:
            self.assertEqual(42, parent.session_id)

    def _get_drive_root_parts(self, parts):
        path = self.cls(*parts)
        return path.drive, path.root, path.parts

    def _check_drive_root_parts(self, arg, *expected):
        sep = self.flavour.sep
        actual = self._get_drive_root_parts([x.replace('/', sep) for x in arg])
        self.assertEqual(actual, expected)
        if altsep := self.flavour.altsep:
            actual = self._get_drive_root_parts([x.replace('/', altsep) for x in arg])
            self.assertEqual(actual, expected)

    def test_drive_root_parts_common(self):
        check = self._check_drive_root_parts
        sep = self.flavour.sep
        # Unanchored parts.
        check((),                   '', '', ())
        check(('a',),               '', '', ('a',))
        check(('a/',),              '', '', ('a',))
        check(('a', 'b'),           '', '', ('a', 'b'))
        # Expansion.
        check(('a/b',),             '', '', ('a', 'b'))
        check(('a/b/',),            '', '', ('a', 'b'))
        check(('a', 'b/c', 'd'),    '', '', ('a', 'b', 'c', 'd'))
        # Collapsing and stripping excess slashes.
        check(('a', 'b//c', 'd'),   '', '', ('a', 'b', 'c', 'd'))
        check(('a', 'b/c/', 'd'),   '', '', ('a', 'b', 'c', 'd'))
        # Eliminating standalone dots.
        check(('.',),               '', '', ())
        check(('.', '.', 'b'),      '', '', ('b',))
        check(('a', '.', 'b'),      '', '', ('a', 'b'))
        check(('a', '.', '.'),      '', '', ('a',))
        # The first part is anchored.
        check(('/a/b',),            '', sep, (sep, 'a', 'b'))
        check(('/a', 'b'),          '', sep, (sep, 'a', 'b'))
        check(('/a/', 'b'),         '', sep, (sep, 'a', 'b'))
        # Ignoring parts before an anchored part.
        check(('a', '/b', 'c'),     '', sep, (sep, 'b', 'c'))
        check(('a', '/b', '/c'),    '', sep, (sep, 'c'))

    def test_join_common(self):
        P = self.cls
        p = P('a/b')
        pp = p.joinpath('c')
        self.assertEqual(pp, P('a/b/c'))
        self.assertIs(type(pp), type(p))
        pp = p.joinpath('c', 'd')
        self.assertEqual(pp, P('a/b/c/d'))
        pp = p.joinpath(P('c'))
        self.assertEqual(pp, P('a/b/c'))
        pp = p.joinpath('/c')
        self.assertEqual(pp, P('/c'))

    def test_div_common(self):
        # Basically the same as joinpath().
        P = self.cls
        p = P('a/b')
        pp = p / 'c'
        self.assertEqual(pp, P('a/b/c'))
        self.assertIs(type(pp), type(p))
        pp = p / 'c/d'
        self.assertEqual(pp, P('a/b/c/d'))
        pp = p / 'c' / 'd'
        self.assertEqual(pp, P('a/b/c/d'))
        pp = 'c' / p / 'd'
        self.assertEqual(pp, P('c/a/b/d'))
        pp = p / P('c')
        self.assertEqual(pp, P('a/b/c'))
        pp = p/ '/c'
        self.assertEqual(pp, P('/c'))

    def _check_str(self, expected, args):
        p = self.cls(*args)
        self.assertEqual(str(p), expected.replace('/', self.sep))

    def test_str_common(self):
        # Canonicalized paths roundtrip.
        for pathstr in ('a', 'a/b', 'a/b/c', '/', '/a/b', '/a/b/c'):
            self._check_str(pathstr, (pathstr,))
        # Special case for the empty path.
        self._check_str('.', ('',))
        # Other tests for str() are in test_equivalences().

    def test_as_posix_common(self):
        P = self.cls
        for pathstr in ('a', 'a/b', 'a/b/c', '/', '/a/b', '/a/b/c'):
            self.assertEqual(P(pathstr).as_posix(), pathstr)
        # Other tests for as_posix() are in test_equivalences().

    def test_as_bytes_common(self):
        sep = os.fsencode(self.sep)
        P = self.cls
        self.assertEqual(bytes(P('a/b')), b'a' + sep + b'b')

    def test_as_uri_common(self):
        P = self.cls
        with self.assertRaises(ValueError):
            P('a').as_uri()
        with self.assertRaises(ValueError):
            P().as_uri()

    def test_repr_common(self):
        for pathstr in ('a', 'a/b', 'a/b/c', '/', '/a/b', '/a/b/c'):
            with self.subTest(pathstr=pathstr):
                p = self.cls(pathstr)
                clsname = p.__class__.__name__
                r = repr(p)
                # The repr() is in the form ClassName("forward-slashes path").
                self.assertTrue(r.startswith(clsname + '('), r)
                self.assertTrue(r.endswith(')'), r)
                inner = r[len(clsname) + 1 : -1]
                self.assertEqual(eval(inner), p.as_posix())

    def test_repr_roundtrips(self):
        for pathstr in ('a', 'a/b', 'a/b/c', '/', '/a/b', '/a/b/c'):
            with self.subTest(pathstr=pathstr):
                p = self.cls(pathstr)
                r = repr(p)
                # The repr() roundtrips.
                q = eval(r, pathlib.__dict__)
                self.assertIs(q.__class__, p.__class__)
                self.assertEqual(q, p)
                self.assertEqual(repr(q), r)

    def test_eq_common(self):
        P = self.cls
        self.assertEqual(P('a/b'), P('a/b'))
        self.assertEqual(P('a/b'), P('a', 'b'))
        self.assertNotEqual(P('a/b'), P('a'))
        self.assertNotEqual(P('a/b'), P('/a/b'))
        self.assertNotEqual(P('a/b'), P())
        self.assertNotEqual(P('/a/b'), P('/'))
        self.assertNotEqual(P(), P('/'))
        self.assertNotEqual(P(), "")
        self.assertNotEqual(P(), {})
        self.assertNotEqual(P(), int)

    def test_match_common(self):
        P = self.cls
        self.assertRaises(ValueError, P('a').match, '')
        self.assertRaises(ValueError, P('a').match, '.')
        # Simple relative pattern.
        self.assertTrue(P('b.py').match('b.py'))
        self.assertTrue(P('a/b.py').match('b.py'))
        self.assertTrue(P('/a/b.py').match('b.py'))
        self.assertFalse(P('a.py').match('b.py'))
        self.assertFalse(P('b/py').match('b.py'))
        self.assertFalse(P('/a.py').match('b.py'))
        self.assertFalse(P('b.py/c').match('b.py'))
        # Wildcard relative pattern.
        self.assertTrue(P('b.py').match('*.py'))
        self.assertTrue(P('a/b.py').match('*.py'))
        self.assertTrue(P('/a/b.py').match('*.py'))
        self.assertFalse(P('b.pyc').match('*.py'))
        self.assertFalse(P('b./py').match('*.py'))
        self.assertFalse(P('b.py/c').match('*.py'))
        # Multi-part relative pattern.
        self.assertTrue(P('ab/c.py').match('a*/*.py'))
        self.assertTrue(P('/d/ab/c.py').match('a*/*.py'))
        self.assertFalse(P('a.py').match('a*/*.py'))
        self.assertFalse(P('/dab/c.py').match('a*/*.py'))
        self.assertFalse(P('ab/c.py/d').match('a*/*.py'))
        # Absolute pattern.
        self.assertTrue(P('/b.py').match('/*.py'))
        self.assertFalse(P('b.py').match('/*.py'))
        self.assertFalse(P('a/b.py').match('/*.py'))
        self.assertFalse(P('/a/b.py').match('/*.py'))
        # Multi-part absolute pattern.
        self.assertTrue(P('/a/b.py').match('/a/*.py'))
        self.assertFalse(P('/ab.py').match('/a/*.py'))
        self.assertFalse(P('/a/b/c.py').match('/a/*.py'))
        # Multi-part glob-style pattern.
        self.assertTrue(P('a').match('**'))
        self.assertTrue(P('c.py').match('**'))
        self.assertTrue(P('a/b/c.py').match('**'))
        self.assertTrue(P('/a/b/c.py').match('**'))
        self.assertTrue(P('/a/b/c.py').match('/**'))
        self.assertTrue(P('/a/b/c.py').match('**/'))
        self.assertTrue(P('/a/b/c.py').match('/a/**'))
        self.assertTrue(P('/a/b/c.py').match('**/*.py'))
        self.assertTrue(P('/a/b/c.py').match('/**/*.py'))
        self.assertTrue(P('/a/b/c.py').match('/a/**/*.py'))
        self.assertTrue(P('/a/b/c.py').match('/a/b/**/*.py'))
        self.assertTrue(P('/a/b/c.py').match('/**/**/**/**/*.py'))
        self.assertFalse(P('c.py').match('**/a.py'))
        self.assertFalse(P('c.py').match('c/**'))
        self.assertFalse(P('a/b/c.py').match('**/a'))
        self.assertFalse(P('a/b/c.py').match('**/a/b'))
        self.assertFalse(P('a/b/c.py').match('**/a/b/c'))
        self.assertFalse(P('a/b/c.py').match('**/a/b/c.'))
        self.assertFalse(P('a/b/c.py').match('**/a/b/c./**'))
        self.assertFalse(P('a/b/c.py').match('**/a/b/c./**'))
        self.assertFalse(P('a/b/c.py').match('/a/b/c.py/**'))
        self.assertFalse(P('a/b/c.py').match('/**/a/b/c.py'))
        self.assertRaises(ValueError, P('a').match, '**a/b/c')
        self.assertRaises(ValueError, P('a').match, 'a/b/c**')
        # Case-sensitive flag
        self.assertFalse(P('A.py').match('a.PY', case_sensitive=True))
        self.assertTrue(P('A.py').match('a.PY', case_sensitive=False))
        self.assertFalse(P('c:/a/B.Py').match('C:/A/*.pY', case_sensitive=True))
        self.assertTrue(P('/a/b/c.py').match('/A/*/*.Py', case_sensitive=False))
        # Matching against empty path
        self.assertFalse(P().match('*'))
        self.assertTrue(P().match('**'))
        self.assertFalse(P().match('**/*'))

    def test_ordering_common(self):
        # Ordering is tuple-alike.
        def assertLess(a, b):
            self.assertLess(a, b)
            self.assertGreater(b, a)
        P = self.cls
        a = P('a')
        b = P('a/b')
        c = P('abc')
        d = P('b')
        assertLess(a, b)
        assertLess(a, c)
        assertLess(a, d)
        assertLess(b, c)
        assertLess(c, d)
        P = self.cls
        a = P('/a')
        b = P('/a/b')
        c = P('/abc')
        d = P('/b')
        assertLess(a, b)
        assertLess(a, c)
        assertLess(a, d)
        assertLess(b, c)
        assertLess(c, d)
        with self.assertRaises(TypeError):
            P() < {}

    def test_parts_common(self):
        # `parts` returns a tuple.
        sep = self.sep
        P = self.cls
        p = P('a/b')
        parts = p.parts
        self.assertEqual(parts, ('a', 'b'))
        # When the path is absolute, the anchor is a separate part.
        p = P('/a/b')
        parts = p.parts
        self.assertEqual(parts, (sep, 'a', 'b'))

    def test_fspath_common(self):
        P = self.cls
        p = P('a/b')
        self._check_str(p.__fspath__(), ('a/b',))
        self._check_str(os.fspath(p), ('a/b',))

    def test_equivalences(self):
        for k, tuples in self.equivalences.items():
            canon = k.replace('/', self.sep)
            posix = k.replace(self.sep, '/')
            if canon != posix:
                tuples = tuples + [
                    tuple(part.replace('/', self.sep) for part in t)
                    for t in tuples
                    ]
                tuples.append((posix, ))
            pcanon = self.cls(canon)
            for t in tuples:
                p = self.cls(*t)
                self.assertEqual(p, pcanon, "failed with args {}".format(t))
                self.assertEqual(hash(p), hash(pcanon))
                self.assertEqual(str(p), canon)
                self.assertEqual(p.as_posix(), posix)

    def test_parent_common(self):
        # Relative
        P = self.cls
        p = P('a/b/c')
        self.assertEqual(p.parent, P('a/b'))
        self.assertEqual(p.parent.parent, P('a'))
        self.assertEqual(p.parent.parent.parent, P())
        self.assertEqual(p.parent.parent.parent.parent, P())
        # Anchored
        p = P('/a/b/c')
        self.assertEqual(p.parent, P('/a/b'))
        self.assertEqual(p.parent.parent, P('/a'))
        self.assertEqual(p.parent.parent.parent, P('/'))
        self.assertEqual(p.parent.parent.parent.parent, P('/'))

    def test_parents_common(self):
        # Relative
        P = self.cls
        p = P('a/b/c')
        par = p.parents
        self.assertEqual(len(par), 3)
        self.assertEqual(par[0], P('a/b'))
        self.assertEqual(par[1], P('a'))
        self.assertEqual(par[2], P('.'))
        self.assertEqual(par[-1], P('.'))
        self.assertEqual(par[-2], P('a'))
        self.assertEqual(par[-3], P('a/b'))
        self.assertEqual(par[0:1], (P('a/b'),))
        self.assertEqual(par[:2], (P('a/b'), P('a')))
        self.assertEqual(par[:-1], (P('a/b'), P('a')))
        self.assertEqual(par[1:], (P('a'), P('.')))
        self.assertEqual(par[::2], (P('a/b'), P('.')))
        self.assertEqual(par[::-1], (P('.'), P('a'), P('a/b')))
        self.assertEqual(list(par), [P('a/b'), P('a'), P('.')])
        with self.assertRaises(IndexError):
            par[-4]
        with self.assertRaises(IndexError):
            par[3]
        with self.assertRaises(TypeError):
            par[0] = p
        # Anchored
        p = P('/a/b/c')
        par = p.parents
        self.assertEqual(len(par), 3)
        self.assertEqual(par[0], P('/a/b'))
        self.assertEqual(par[1], P('/a'))
        self.assertEqual(par[2], P('/'))
        self.assertEqual(par[-1], P('/'))
        self.assertEqual(par[-2], P('/a'))
        self.assertEqual(par[-3], P('/a/b'))
        self.assertEqual(par[0:1], (P('/a/b'),))
        self.assertEqual(par[:2], (P('/a/b'), P('/a')))
        self.assertEqual(par[:-1], (P('/a/b'), P('/a')))
        self.assertEqual(par[1:], (P('/a'), P('/')))
        self.assertEqual(par[::2], (P('/a/b'), P('/')))
        self.assertEqual(par[::-1], (P('/'), P('/a'), P('/a/b')))
        self.assertEqual(list(par), [P('/a/b'), P('/a'), P('/')])
        with self.assertRaises(IndexError):
            par[-4]
        with self.assertRaises(IndexError):
            par[3]

    def test_drive_common(self):
        P = self.cls
        self.assertEqual(P('a/b').drive, '')
        self.assertEqual(P('/a/b').drive, '')
        self.assertEqual(P('').drive, '')

    def test_root_common(self):
        P = self.cls
        sep = self.sep
        self.assertEqual(P('').root, '')
        self.assertEqual(P('a/b').root, '')
        self.assertEqual(P('/').root, sep)
        self.assertEqual(P('/a/b').root, sep)

    def test_anchor_common(self):
        P = self.cls
        sep = self.sep
        self.assertEqual(P('').anchor, '')
        self.assertEqual(P('a/b').anchor, '')
        self.assertEqual(P('/').anchor, sep)
        self.assertEqual(P('/a/b').anchor, sep)

    def test_name_common(self):
        P = self.cls
        self.assertEqual(P('').name, '')
        self.assertEqual(P('.').name, '')
        self.assertEqual(P('/').name, '')
        self.assertEqual(P('a/b').name, 'b')
        self.assertEqual(P('/a/b').name, 'b')
        self.assertEqual(P('/a/b/.').name, 'b')
        self.assertEqual(P('a/b.py').name, 'b.py')
        self.assertEqual(P('/a/b.py').name, 'b.py')

    def test_suffix_common(self):
        P = self.cls
        self.assertEqual(P('').suffix, '')
        self.assertEqual(P('.').suffix, '')
        self.assertEqual(P('..').suffix, '')
        self.assertEqual(P('/').suffix, '')
        self.assertEqual(P('a/b').suffix, '')
        self.assertEqual(P('/a/b').suffix, '')
        self.assertEqual(P('/a/b/.').suffix, '')
        self.assertEqual(P('a/b.py').suffix, '.py')
        self.assertEqual(P('/a/b.py').suffix, '.py')
        self.assertEqual(P('a/.hgrc').suffix, '')
        self.assertEqual(P('/a/.hgrc').suffix, '')
        self.assertEqual(P('a/.hg.rc').suffix, '.rc')
        self.assertEqual(P('/a/.hg.rc').suffix, '.rc')
        self.assertEqual(P('a/b.tar.gz').suffix, '.gz')
        self.assertEqual(P('/a/b.tar.gz').suffix, '.gz')
        self.assertEqual(P('a/Some name. Ending with a dot.').suffix, '')
        self.assertEqual(P('/a/Some name. Ending with a dot.').suffix, '')

    def test_suffixes_common(self):
        P = self.cls
        self.assertEqual(P('').suffixes, [])
        self.assertEqual(P('.').suffixes, [])
        self.assertEqual(P('/').suffixes, [])
        self.assertEqual(P('a/b').suffixes, [])
        self.assertEqual(P('/a/b').suffixes, [])
        self.assertEqual(P('/a/b/.').suffixes, [])
        self.assertEqual(P('a/b.py').suffixes, ['.py'])
        self.assertEqual(P('/a/b.py').suffixes, ['.py'])
        self.assertEqual(P('a/.hgrc').suffixes, [])
        self.assertEqual(P('/a/.hgrc').suffixes, [])
        self.assertEqual(P('a/.hg.rc').suffixes, ['.rc'])
        self.assertEqual(P('/a/.hg.rc').suffixes, ['.rc'])
        self.assertEqual(P('a/b.tar.gz').suffixes, ['.tar', '.gz'])
        self.assertEqual(P('/a/b.tar.gz').suffixes, ['.tar', '.gz'])
        self.assertEqual(P('a/Some name. Ending with a dot.').suffixes, [])
        self.assertEqual(P('/a/Some name. Ending with a dot.').suffixes, [])

    def test_stem_common(self):
        P = self.cls
        self.assertEqual(P('').stem, '')
        self.assertEqual(P('.').stem, '')
        self.assertEqual(P('..').stem, '..')
        self.assertEqual(P('/').stem, '')
        self.assertEqual(P('a/b').stem, 'b')
        self.assertEqual(P('a/b.py').stem, 'b')
        self.assertEqual(P('a/.hgrc').stem, '.hgrc')
        self.assertEqual(P('a/.hg.rc').stem, '.hg')
        self.assertEqual(P('a/b.tar.gz').stem, 'b.tar')
        self.assertEqual(P('a/Some name. Ending with a dot.').stem,
                         'Some name. Ending with a dot.')

    def test_with_name_common(self):
        P = self.cls
        self.assertEqual(P('a/b').with_name('d.xml'), P('a/d.xml'))
        self.assertEqual(P('/a/b').with_name('d.xml'), P('/a/d.xml'))
        self.assertEqual(P('a/b.py').with_name('d.xml'), P('a/d.xml'))
        self.assertEqual(P('/a/b.py').with_name('d.xml'), P('/a/d.xml'))
        self.assertEqual(P('a/Dot ending.').with_name('d.xml'), P('a/d.xml'))
        self.assertEqual(P('/a/Dot ending.').with_name('d.xml'), P('/a/d.xml'))
        self.assertRaises(ValueError, P('').with_name, 'd.xml')
        self.assertRaises(ValueError, P('.').with_name, 'd.xml')
        self.assertRaises(ValueError, P('/').with_name, 'd.xml')
        self.assertRaises(ValueError, P('a/b').with_name, '')
        self.assertRaises(ValueError, P('a/b').with_name, '/c')
        self.assertRaises(ValueError, P('a/b').with_name, 'c/')
        self.assertRaises(ValueError, P('a/b').with_name, 'c/d')

    def test_with_stem_common(self):
        P = self.cls
        self.assertEqual(P('a/b').with_stem('d'), P('a/d'))
        self.assertEqual(P('/a/b').with_stem('d'), P('/a/d'))
        self.assertEqual(P('a/b.py').with_stem('d'), P('a/d.py'))
        self.assertEqual(P('/a/b.py').with_stem('d'), P('/a/d.py'))
        self.assertEqual(P('/a/b.tar.gz').with_stem('d'), P('/a/d.gz'))
        self.assertEqual(P('a/Dot ending.').with_stem('d'), P('a/d'))
        self.assertEqual(P('/a/Dot ending.').with_stem('d'), P('/a/d'))
        self.assertRaises(ValueError, P('').with_stem, 'd')
        self.assertRaises(ValueError, P('.').with_stem, 'd')
        self.assertRaises(ValueError, P('/').with_stem, 'd')
        self.assertRaises(ValueError, P('a/b').with_stem, '')
        self.assertRaises(ValueError, P('a/b').with_stem, '/c')
        self.assertRaises(ValueError, P('a/b').with_stem, 'c/')
        self.assertRaises(ValueError, P('a/b').with_stem, 'c/d')

    def test_with_suffix_common(self):
        P = self.cls
        self.assertEqual(P('a/b').with_suffix('.gz'), P('a/b.gz'))
        self.assertEqual(P('/a/b').with_suffix('.gz'), P('/a/b.gz'))
        self.assertEqual(P('a/b.py').with_suffix('.gz'), P('a/b.gz'))
        self.assertEqual(P('/a/b.py').with_suffix('.gz'), P('/a/b.gz'))
        # Stripping suffix.
        self.assertEqual(P('a/b.py').with_suffix(''), P('a/b'))
        self.assertEqual(P('/a/b').with_suffix(''), P('/a/b'))
        # Path doesn't have a "filename" component.
        self.assertRaises(ValueError, P('').with_suffix, '.gz')
        self.assertRaises(ValueError, P('.').with_suffix, '.gz')
        self.assertRaises(ValueError, P('/').with_suffix, '.gz')
        # Invalid suffix.
        self.assertRaises(ValueError, P('a/b').with_suffix, 'gz')
        self.assertRaises(ValueError, P('a/b').with_suffix, '/')
        self.assertRaises(ValueError, P('a/b').with_suffix, '.')
        self.assertRaises(ValueError, P('a/b').with_suffix, '/.gz')
        self.assertRaises(ValueError, P('a/b').with_suffix, 'c/d')
        self.assertRaises(ValueError, P('a/b').with_suffix, '.c/.d')
        self.assertRaises(ValueError, P('a/b').with_suffix, './.d')
        self.assertRaises(ValueError, P('a/b').with_suffix, '.d/.')
        self.assertRaises(ValueError, P('a/b').with_suffix,
                          (self.flavour.sep, 'd'))

    def test_relative_to_common(self):
        P = self.cls
        p = P('a/b')
        self.assertRaises(TypeError, p.relative_to)
        self.assertRaises(TypeError, p.relative_to, b'a')
        self.assertEqual(p.relative_to(P()), P('a/b'))
        self.assertEqual(p.relative_to(''), P('a/b'))
        self.assertEqual(p.relative_to(P('a')), P('b'))
        self.assertEqual(p.relative_to('a'), P('b'))
        self.assertEqual(p.relative_to('a/'), P('b'))
        self.assertEqual(p.relative_to(P('a/b')), P())
        self.assertEqual(p.relative_to('a/b'), P())
        self.assertEqual(p.relative_to(P(), walk_up=True), P('a/b'))
        self.assertEqual(p.relative_to('', walk_up=True), P('a/b'))
        self.assertEqual(p.relative_to(P('a'), walk_up=True), P('b'))
        self.assertEqual(p.relative_to('a', walk_up=True), P('b'))
        self.assertEqual(p.relative_to('a/', walk_up=True), P('b'))
        self.assertEqual(p.relative_to(P('a/b'), walk_up=True), P())
        self.assertEqual(p.relative_to('a/b', walk_up=True), P())
        self.assertEqual(p.relative_to(P('a/c'), walk_up=True), P('../b'))
        self.assertEqual(p.relative_to('a/c', walk_up=True), P('../b'))
        self.assertEqual(p.relative_to(P('a/b/c'), walk_up=True), P('..'))
        self.assertEqual(p.relative_to('a/b/c', walk_up=True), P('..'))
        self.assertEqual(p.relative_to(P('c'), walk_up=True), P('../a/b'))
        self.assertEqual(p.relative_to('c', walk_up=True), P('../a/b'))
        # With several args.
        with self.assertWarns(DeprecationWarning):
            p.relative_to('a', 'b')
            p.relative_to('a', 'b', walk_up=True)
        # Unrelated paths.
        self.assertRaises(ValueError, p.relative_to, P('c'))
        self.assertRaises(ValueError, p.relative_to, P('a/b/c'))
        self.assertRaises(ValueError, p.relative_to, P('a/c'))
        self.assertRaises(ValueError, p.relative_to, P('/a'))
        self.assertRaises(ValueError, p.relative_to, P('/'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('/a'), walk_up=True)
        p = P('/a/b')
        self.assertEqual(p.relative_to(P('/')), P('a/b'))
        self.assertEqual(p.relative_to('/'), P('a/b'))
        self.assertEqual(p.relative_to(P('/a')), P('b'))
        self.assertEqual(p.relative_to('/a'), P('b'))
        self.assertEqual(p.relative_to('/a/'), P('b'))
        self.assertEqual(p.relative_to(P('/a/b')), P())
        self.assertEqual(p.relative_to('/a/b'), P())
        self.assertEqual(p.relative_to(P('/'), walk_up=True), P('a/b'))
        self.assertEqual(p.relative_to('/', walk_up=True), P('a/b'))
        self.assertEqual(p.relative_to(P('/a'), walk_up=True), P('b'))
        self.assertEqual(p.relative_to('/a', walk_up=True), P('b'))
        self.assertEqual(p.relative_to('/a/', walk_up=True), P('b'))
        self.assertEqual(p.relative_to(P('/a/b'), walk_up=True), P())
        self.assertEqual(p.relative_to('/a/b', walk_up=True), P())
        self.assertEqual(p.relative_to(P('/a/c'), walk_up=True), P('../b'))
        self.assertEqual(p.relative_to('/a/c', walk_up=True), P('../b'))
        self.assertEqual(p.relative_to(P('/a/b/c'), walk_up=True), P('..'))
        self.assertEqual(p.relative_to('/a/b/c', walk_up=True), P('..'))
        self.assertEqual(p.relative_to(P('/c'), walk_up=True), P('../a/b'))
        self.assertEqual(p.relative_to('/c', walk_up=True), P('../a/b'))
        # Unrelated paths.
        self.assertRaises(ValueError, p.relative_to, P('/c'))
        self.assertRaises(ValueError, p.relative_to, P('/a/b/c'))
        self.assertRaises(ValueError, p.relative_to, P('/a/c'))
        self.assertRaises(ValueError, p.relative_to, P())
        self.assertRaises(ValueError, p.relative_to, '')
        self.assertRaises(ValueError, p.relative_to, P('a'))
        self.assertRaises(ValueError, p.relative_to, P(''), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('a'), walk_up=True)

    def test_is_relative_to_common(self):
        P = self.cls
        p = P('a/b')
        self.assertRaises(TypeError, p.is_relative_to)
        self.assertRaises(TypeError, p.is_relative_to, b'a')
        self.assertTrue(p.is_relative_to(P()))
        self.assertTrue(p.is_relative_to(''))
        self.assertTrue(p.is_relative_to(P('a')))
        self.assertTrue(p.is_relative_to('a/'))
        self.assertTrue(p.is_relative_to(P('a/b')))
        self.assertTrue(p.is_relative_to('a/b'))
        # With several args.
        with self.assertWarns(DeprecationWarning):
            p.is_relative_to('a', 'b')
        # Unrelated paths.
        self.assertFalse(p.is_relative_to(P('c')))
        self.assertFalse(p.is_relative_to(P('a/b/c')))
        self.assertFalse(p.is_relative_to(P('a/c')))
        self.assertFalse(p.is_relative_to(P('/a')))
        p = P('/a/b')
        self.assertTrue(p.is_relative_to(P('/')))
        self.assertTrue(p.is_relative_to('/'))
        self.assertTrue(p.is_relative_to(P('/a')))
        self.assertTrue(p.is_relative_to('/a'))
        self.assertTrue(p.is_relative_to('/a/'))
        self.assertTrue(p.is_relative_to(P('/a/b')))
        self.assertTrue(p.is_relative_to('/a/b'))
        # Unrelated paths.
        self.assertFalse(p.is_relative_to(P('/c')))
        self.assertFalse(p.is_relative_to(P('/a/b/c')))
        self.assertFalse(p.is_relative_to(P('/a/c')))
        self.assertFalse(p.is_relative_to(P()))
        self.assertFalse(p.is_relative_to(''))
        self.assertFalse(p.is_relative_to(P('a')))

    def test_pickling_common(self):
        P = self.cls
        p = P('/a/b')
        for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
            dumped = pickle.dumps(p, proto)
            pp = pickle.loads(dumped)
            self.assertIs(pp.__class__, p.__class__)
            self.assertEqual(pp, p)
            self.assertEqual(hash(pp), hash(p))
            self.assertEqual(str(pp), str(p))


class PurePosixPathTest(PurePathTest):
    cls = pathlib.PurePosixPath

    def test_drive_root_parts(self):
        check = self._check_drive_root_parts
        # Collapsing of excess leading slashes, except for the double-slash
        # special case.
        check(('//a', 'b'),             '', '//', ('//', 'a', 'b'))
        check(('///a', 'b'),            '', '/', ('/', 'a', 'b'))
        check(('////a', 'b'),           '', '/', ('/', 'a', 'b'))
        # Paths which look like NT paths aren't treated specially.
        check(('c:a',),                 '', '', ('c:a',))
        check(('c:\\a',),               '', '', ('c:\\a',))
        check(('\\a',),                 '', '', ('\\a',))

    def test_root(self):
        P = self.cls
        self.assertEqual(P('/a/b').root, '/')
        self.assertEqual(P('///a/b').root, '/')
        # POSIX special case for two leading slashes.
        self.assertEqual(P('//a/b').root, '//')

    def test_eq(self):
        P = self.cls
        self.assertNotEqual(P('a/b'), P('A/b'))
        self.assertEqual(P('/a'), P('///a'))
        self.assertNotEqual(P('/a'), P('//a'))

    def test_as_uri(self):
        P = self.cls
        self.assertEqual(P('/').as_uri(), 'file:///')
        self.assertEqual(P('/a/b.c').as_uri(), 'file:///a/b.c')
        self.assertEqual(P('/a/b%#c').as_uri(), 'file:///a/b%25%23c')

    def test_as_uri_non_ascii(self):
        from urllib.parse import quote_from_bytes
        P = self.cls
        try:
            os.fsencode('\xe9')
        except UnicodeEncodeError:
            self.skipTest("\\xe9 cannot be encoded to the filesystem encoding")
        self.assertEqual(P('/a/b\xe9').as_uri(),
                         'file:///a/b' + quote_from_bytes(os.fsencode('\xe9')))

    def test_match(self):
        P = self.cls
        self.assertFalse(P('A.py').match('a.PY'))

    def test_is_absolute(self):
        P = self.cls
        self.assertFalse(P().is_absolute())
        self.assertFalse(P('a').is_absolute())
        self.assertFalse(P('a/b/').is_absolute())
        self.assertTrue(P('/').is_absolute())
        self.assertTrue(P('/a').is_absolute())
        self.assertTrue(P('/a/b/').is_absolute())
        self.assertTrue(P('//a').is_absolute())
        self.assertTrue(P('//a/b').is_absolute())

    def test_is_reserved(self):
        P = self.cls
        self.assertIs(False, P('').is_reserved())
        self.assertIs(False, P('/').is_reserved())
        self.assertIs(False, P('/foo/bar').is_reserved())
        self.assertIs(False, P('/dev/con/PRN/NUL').is_reserved())

    def test_join(self):
        P = self.cls
        p = P('//a')
        pp = p.joinpath('b')
        self.assertEqual(pp, P('//a/b'))
        pp = P('/a').joinpath('//c')
        self.assertEqual(pp, P('//c'))
        pp = P('//a').joinpath('/c')
        self.assertEqual(pp, P('/c'))

    def test_div(self):
        # Basically the same as joinpath().
        P = self.cls
        p = P('//a')
        pp = p / 'b'
        self.assertEqual(pp, P('//a/b'))
        pp = P('/a') / '//c'
        self.assertEqual(pp, P('//c'))
        pp = P('//a') / '/c'
        self.assertEqual(pp, P('/c'))

    def test_parse_windows_path(self):
        P = self.cls
        p = P('c:', 'a', 'b')
        pp = P(pathlib.PureWindowsPath('c:\\a\\b'))
        self.assertEqual(p, pp)


class PureWindowsPathTest(PurePathTest):
    cls = pathlib.PureWindowsPath

    equivalences = PurePathTest.equivalences.copy()
    equivalences.update({
        './a:b': [ ('./a:b',) ],
        'c:a': [ ('c:', 'a'), ('c:', 'a/'), ('.', 'c:', 'a') ],
        'c:/a': [
            ('c:/', 'a'), ('c:', '/', 'a'), ('c:', '/a'),
            ('/z', 'c:/', 'a'), ('//x/y', 'c:/', 'a'),
            ],
        '//a/b/': [ ('//a/b',) ],
        '//a/b/c': [
            ('//a/b', 'c'), ('//a/b/', 'c'),
            ],
    })

    def test_drive_root_parts(self):
        check = self._check_drive_root_parts
        # First part is anchored.
        check(('c:',),                  'c:', '', ('c:',))
        check(('c:/',),                 'c:', '\\', ('c:\\',))
        check(('/',),                   '', '\\', ('\\',))
        check(('c:a',),                 'c:', '', ('c:', 'a'))
        check(('c:/a',),                'c:', '\\', ('c:\\', 'a'))
        check(('/a',),                  '', '\\', ('\\', 'a'))
        # UNC paths.
        check(('//',),                  '\\\\', '', ('\\\\',))
        check(('//a',),                 '\\\\a', '', ('\\\\a',))
        check(('//a/',),                '\\\\a\\', '', ('\\\\a\\',))
        check(('//a/b',),               '\\\\a\\b', '\\', ('\\\\a\\b\\',))
        check(('//a/b/',),              '\\\\a\\b', '\\', ('\\\\a\\b\\',))
        check(('//a/b/c',),             '\\\\a\\b', '\\', ('\\\\a\\b\\', 'c'))
        # Second part is anchored, so that the first part is ignored.
        check(('a', 'Z:b', 'c'),        'Z:', '', ('Z:', 'b', 'c'))
        check(('a', 'Z:/b', 'c'),       'Z:', '\\', ('Z:\\', 'b', 'c'))
        # UNC paths.
        check(('a', '//b/c', 'd'),      '\\\\b\\c', '\\', ('\\\\b\\c\\', 'd'))
        # Collapsing and stripping excess slashes.
        check(('a', 'Z://b//c/', 'd/'), 'Z:', '\\', ('Z:\\', 'b', 'c', 'd'))
        # UNC paths.
        check(('a', '//b/c//', 'd'),    '\\\\b\\c', '\\', ('\\\\b\\c\\', 'd'))
        # Extended paths.
        check(('//./c:',),              '\\\\.\\c:', '', ('\\\\.\\c:',))
        check(('//?/c:/',),             '\\\\?\\c:', '\\', ('\\\\?\\c:\\',))
        check(('//?/c:/a',),            '\\\\?\\c:', '\\', ('\\\\?\\c:\\', 'a'))
        check(('//?/c:/a', '/b'),       '\\\\?\\c:', '\\', ('\\\\?\\c:\\', 'b'))
        # Extended UNC paths (format is "\\?\UNC\server\share").
        check(('//?',),                 '\\\\?', '', ('\\\\?',))
        check(('//?/',),                '\\\\?\\', '', ('\\\\?\\',))
        check(('//?/UNC',),             '\\\\?\\UNC', '', ('\\\\?\\UNC',))
        check(('//?/UNC/',),            '\\\\?\\UNC\\', '', ('\\\\?\\UNC\\',))
        check(('//?/UNC/b',),           '\\\\?\\UNC\\b', '', ('\\\\?\\UNC\\b',))
        check(('//?/UNC/b/',),          '\\\\?\\UNC\\b\\', '', ('\\\\?\\UNC\\b\\',))
        check(('//?/UNC/b/c',),         '\\\\?\\UNC\\b\\c', '\\', ('\\\\?\\UNC\\b\\c\\',))
        check(('//?/UNC/b/c/',),        '\\\\?\\UNC\\b\\c', '\\', ('\\\\?\\UNC\\b\\c\\',))
        check(('//?/UNC/b/c/d',),       '\\\\?\\UNC\\b\\c', '\\', ('\\\\?\\UNC\\b\\c\\', 'd'))
        # UNC device paths
        check(('//./BootPartition/',),   '\\\\.\\BootPartition', '\\', ('\\\\.\\BootPartition\\',))
        check(('//?/BootPartition/',),   '\\\\?\\BootPartition', '\\', ('\\\\?\\BootPartition\\',))
        check(('//./PhysicalDrive0',),   '\\\\.\\PhysicalDrive0', '', ('\\\\.\\PhysicalDrive0',))
        check(('//?/Volume{}/',),        '\\\\?\\Volume{}', '\\', ('\\\\?\\Volume{}\\',))
        check(('//./nul',),              '\\\\.\\nul', '', ('\\\\.\\nul',))
        # Second part has a root but not drive.
        check(('a', '/b', 'c'),         '', '\\', ('\\', 'b', 'c'))
        check(('Z:/a', '/b', 'c'),      'Z:', '\\', ('Z:\\', 'b', 'c'))
        check(('//?/Z:/a', '/b', 'c'),  '\\\\?\\Z:', '\\', ('\\\\?\\Z:\\', 'b', 'c'))
        # Joining with the same drive => the first path is appended to if
        # the second path is relative.
        check(('c:/a/b', 'c:x/y'),      'c:', '\\', ('c:\\', 'a', 'b', 'x', 'y'))
        check(('c:/a/b', 'c:/x/y'),     'c:', '\\', ('c:\\', 'x', 'y'))
        # Paths to files with NTFS alternate data streams
        check(('./c:s',),               '', '', ('c:s',))
        check(('cc:s',),                '', '', ('cc:s',))
        check(('C:c:s',),               'C:', '', ('C:', 'c:s'))
        check(('C:/c:s',),              'C:', '\\', ('C:\\', 'c:s'))
        check(('D:a', './c:b'),         'D:', '', ('D:', 'a', 'c:b'))
        check(('D:/a', './c:b'),        'D:', '\\', ('D:\\', 'a', 'c:b'))

    def test_str(self):
        p = self.cls('a/b/c')
        self.assertEqual(str(p), 'a\\b\\c')
        p = self.cls('c:/a/b/c')
        self.assertEqual(str(p), 'c:\\a\\b\\c')
        p = self.cls('//a/b')
        self.assertEqual(str(p), '\\\\a\\b\\')
        p = self.cls('//a/b/c')
        self.assertEqual(str(p), '\\\\a\\b\\c')
        p = self.cls('//a/b/c/d')
        self.assertEqual(str(p), '\\\\a\\b\\c\\d')

    def test_str_subclass(self):
        self._check_str_subclass('.\\a:b')
        self._check_str_subclass('c:')
        self._check_str_subclass('c:a')
        self._check_str_subclass('c:a\\b.txt')
        self._check_str_subclass('c:\\')
        self._check_str_subclass('c:\\a')
        self._check_str_subclass('c:\\a\\b.txt')
        self._check_str_subclass('\\\\some\\share')
        self._check_str_subclass('\\\\some\\share\\a')
        self._check_str_subclass('\\\\some\\share\\a\\b.txt')

    def test_eq(self):
        P = self.cls
        self.assertEqual(P('c:a/b'), P('c:a/b'))
        self.assertEqual(P('c:a/b'), P('c:', 'a', 'b'))
        self.assertNotEqual(P('c:a/b'), P('d:a/b'))
        self.assertNotEqual(P('c:a/b'), P('c:/a/b'))
        self.assertNotEqual(P('/a/b'), P('c:/a/b'))
        # Case-insensitivity.
        self.assertEqual(P('a/B'), P('A/b'))
        self.assertEqual(P('C:a/B'), P('c:A/b'))
        self.assertEqual(P('//Some/SHARE/a/B'), P('//somE/share/A/b'))
        self.assertEqual(P('\u0130'), P('i\u0307'))

    def test_as_uri(self):
        P = self.cls
        with self.assertRaises(ValueError):
            P('/a/b').as_uri()
        with self.assertRaises(ValueError):
            P('c:a/b').as_uri()
        self.assertEqual(P('c:/').as_uri(), 'file:///c:/')
        self.assertEqual(P('c:/a/b.c').as_uri(), 'file:///c:/a/b.c')
        self.assertEqual(P('c:/a/b%#c').as_uri(), 'file:///c:/a/b%25%23c')
        self.assertEqual(P('c:/a/b\xe9').as_uri(), 'file:///c:/a/b%C3%A9')
        self.assertEqual(P('//some/share/').as_uri(), 'file://some/share/')
        self.assertEqual(P('//some/share/a/b.c').as_uri(),
                         'file://some/share/a/b.c')
        self.assertEqual(P('//some/share/a/b%#c\xe9').as_uri(),
                         'file://some/share/a/b%25%23c%C3%A9')

    def test_match(self):
        P = self.cls
        # Absolute patterns.
        self.assertTrue(P('c:/b.py').match('*:/*.py'))
        self.assertTrue(P('c:/b.py').match('c:/*.py'))
        self.assertFalse(P('d:/b.py').match('c:/*.py'))  # wrong drive
        self.assertFalse(P('b.py').match('/*.py'))
        self.assertFalse(P('b.py').match('c:*.py'))
        self.assertFalse(P('b.py').match('c:/*.py'))
        self.assertFalse(P('c:b.py').match('/*.py'))
        self.assertFalse(P('c:b.py').match('c:/*.py'))
        self.assertFalse(P('/b.py').match('c:*.py'))
        self.assertFalse(P('/b.py').match('c:/*.py'))
        # UNC patterns.
        self.assertTrue(P('//some/share/a.py').match('//*/*/*.py'))
        self.assertTrue(P('//some/share/a.py').match('//some/share/*.py'))
        self.assertFalse(P('//other/share/a.py').match('//some/share/*.py'))
        self.assertFalse(P('//some/share/a/b.py').match('//some/share/*.py'))
        # Case-insensitivity.
        self.assertTrue(P('B.py').match('b.PY'))
        self.assertTrue(P('c:/a/B.Py').match('C:/A/*.pY'))
        self.assertTrue(P('//Some/Share/B.Py').match('//somE/sharE/*.pY'))
        # Path anchor doesn't match pattern anchor
        self.assertFalse(P('c:/b.py').match('/*.py'))  # 'c:/' vs '/'
        self.assertFalse(P('c:/b.py').match('c:*.py'))  # 'c:/' vs 'c:'
        self.assertFalse(P('//some/share/a.py').match('/*.py'))  # '//some/share/' vs '/'

    def test_ordering_common(self):
        # Case-insensitivity.
        def assertOrderedEqual(a, b):
            self.assertLessEqual(a, b)
            self.assertGreaterEqual(b, a)
        P = self.cls
        p = P('c:A/b')
        q = P('C:a/B')
        assertOrderedEqual(p, q)
        self.assertFalse(p < q)
        self.assertFalse(p > q)
        p = P('//some/Share/A/b')
        q = P('//Some/SHARE/a/B')
        assertOrderedEqual(p, q)
        self.assertFalse(p < q)
        self.assertFalse(p > q)

    def test_parts(self):
        P = self.cls
        p = P('c:a/b')
        parts = p.parts
        self.assertEqual(parts, ('c:', 'a', 'b'))
        p = P('c:/a/b')
        parts = p.parts
        self.assertEqual(parts, ('c:\\', 'a', 'b'))
        p = P('//a/b/c/d')
        parts = p.parts
        self.assertEqual(parts, ('\\\\a\\b\\', 'c', 'd'))

    def test_parent(self):
        # Anchored
        P = self.cls
        p = P('z:a/b/c')
        self.assertEqual(p.parent, P('z:a/b'))
        self.assertEqual(p.parent.parent, P('z:a'))
        self.assertEqual(p.parent.parent.parent, P('z:'))
        self.assertEqual(p.parent.parent.parent.parent, P('z:'))
        p = P('z:/a/b/c')
        self.assertEqual(p.parent, P('z:/a/b'))
        self.assertEqual(p.parent.parent, P('z:/a'))
        self.assertEqual(p.parent.parent.parent, P('z:/'))
        self.assertEqual(p.parent.parent.parent.parent, P('z:/'))
        p = P('//a/b/c/d')
        self.assertEqual(p.parent, P('//a/b/c'))
        self.assertEqual(p.parent.parent, P('//a/b'))
        self.assertEqual(p.parent.parent.parent, P('//a/b'))

    def test_parents(self):
        # Anchored
        P = self.cls
        p = P('z:a/b/')
        par = p.parents
        self.assertEqual(len(par), 2)
        self.assertEqual(par[0], P('z:a'))
        self.assertEqual(par[1], P('z:'))
        self.assertEqual(par[0:1], (P('z:a'),))
        self.assertEqual(par[:-1], (P('z:a'),))
        self.assertEqual(par[:2], (P('z:a'), P('z:')))
        self.assertEqual(par[1:], (P('z:'),))
        self.assertEqual(par[::2], (P('z:a'),))
        self.assertEqual(par[::-1], (P('z:'), P('z:a')))
        self.assertEqual(list(par), [P('z:a'), P('z:')])
        with self.assertRaises(IndexError):
            par[2]
        p = P('z:/a/b/')
        par = p.parents
        self.assertEqual(len(par), 2)
        self.assertEqual(par[0], P('z:/a'))
        self.assertEqual(par[1], P('z:/'))
        self.assertEqual(par[0:1], (P('z:/a'),))
        self.assertEqual(par[0:-1], (P('z:/a'),))
        self.assertEqual(par[:2], (P('z:/a'), P('z:/')))
        self.assertEqual(par[1:], (P('z:/'),))
        self.assertEqual(par[::2], (P('z:/a'),))
        self.assertEqual(par[::-1], (P('z:/'), P('z:/a'),))
        self.assertEqual(list(par), [P('z:/a'), P('z:/')])
        with self.assertRaises(IndexError):
            par[2]
        p = P('//a/b/c/d')
        par = p.parents
        self.assertEqual(len(par), 2)
        self.assertEqual(par[0], P('//a/b/c'))
        self.assertEqual(par[1], P('//a/b'))
        self.assertEqual(par[0:1], (P('//a/b/c'),))
        self.assertEqual(par[0:-1], (P('//a/b/c'),))
        self.assertEqual(par[:2], (P('//a/b/c'), P('//a/b')))
        self.assertEqual(par[1:], (P('//a/b'),))
        self.assertEqual(par[::2], (P('//a/b/c'),))
        self.assertEqual(par[::-1], (P('//a/b'), P('//a/b/c')))
        self.assertEqual(list(par), [P('//a/b/c'), P('//a/b')])
        with self.assertRaises(IndexError):
            par[2]

    def test_drive(self):
        P = self.cls
        self.assertEqual(P('c:').drive, 'c:')
        self.assertEqual(P('c:a/b').drive, 'c:')
        self.assertEqual(P('c:/').drive, 'c:')
        self.assertEqual(P('c:/a/b/').drive, 'c:')
        self.assertEqual(P('//a/b').drive, '\\\\a\\b')
        self.assertEqual(P('//a/b/').drive, '\\\\a\\b')
        self.assertEqual(P('//a/b/c/d').drive, '\\\\a\\b')
        self.assertEqual(P('./c:a').drive, '')

    def test_root(self):
        P = self.cls
        self.assertEqual(P('c:').root, '')
        self.assertEqual(P('c:a/b').root, '')
        self.assertEqual(P('c:/').root, '\\')
        self.assertEqual(P('c:/a/b/').root, '\\')
        self.assertEqual(P('//a/b').root, '\\')
        self.assertEqual(P('//a/b/').root, '\\')
        self.assertEqual(P('//a/b/c/d').root, '\\')

    def test_anchor(self):
        P = self.cls
        self.assertEqual(P('c:').anchor, 'c:')
        self.assertEqual(P('c:a/b').anchor, 'c:')
        self.assertEqual(P('c:/').anchor, 'c:\\')
        self.assertEqual(P('c:/a/b/').anchor, 'c:\\')
        self.assertEqual(P('//a/b').anchor, '\\\\a\\b\\')
        self.assertEqual(P('//a/b/').anchor, '\\\\a\\b\\')
        self.assertEqual(P('//a/b/c/d').anchor, '\\\\a\\b\\')

    def test_name(self):
        P = self.cls
        self.assertEqual(P('c:').name, '')
        self.assertEqual(P('c:/').name, '')
        self.assertEqual(P('c:a/b').name, 'b')
        self.assertEqual(P('c:/a/b').name, 'b')
        self.assertEqual(P('c:a/b.py').name, 'b.py')
        self.assertEqual(P('c:/a/b.py').name, 'b.py')
        self.assertEqual(P('//My.py/Share.php').name, '')
        self.assertEqual(P('//My.py/Share.php/a/b').name, 'b')

    def test_suffix(self):
        P = self.cls
        self.assertEqual(P('c:').suffix, '')
        self.assertEqual(P('c:/').suffix, '')
        self.assertEqual(P('c:a/b').suffix, '')
        self.assertEqual(P('c:/a/b').suffix, '')
        self.assertEqual(P('c:a/b.py').suffix, '.py')
        self.assertEqual(P('c:/a/b.py').suffix, '.py')
        self.assertEqual(P('c:a/.hgrc').suffix, '')
        self.assertEqual(P('c:/a/.hgrc').suffix, '')
        self.assertEqual(P('c:a/.hg.rc').suffix, '.rc')
        self.assertEqual(P('c:/a/.hg.rc').suffix, '.rc')
        self.assertEqual(P('c:a/b.tar.gz').suffix, '.gz')
        self.assertEqual(P('c:/a/b.tar.gz').suffix, '.gz')
        self.assertEqual(P('c:a/Some name. Ending with a dot.').suffix, '')
        self.assertEqual(P('c:/a/Some name. Ending with a dot.').suffix, '')
        self.assertEqual(P('//My.py/Share.php').suffix, '')
        self.assertEqual(P('//My.py/Share.php/a/b').suffix, '')

    def test_suffixes(self):
        P = self.cls
        self.assertEqual(P('c:').suffixes, [])
        self.assertEqual(P('c:/').suffixes, [])
        self.assertEqual(P('c:a/b').suffixes, [])
        self.assertEqual(P('c:/a/b').suffixes, [])
        self.assertEqual(P('c:a/b.py').suffixes, ['.py'])
        self.assertEqual(P('c:/a/b.py').suffixes, ['.py'])
        self.assertEqual(P('c:a/.hgrc').suffixes, [])
        self.assertEqual(P('c:/a/.hgrc').suffixes, [])
        self.assertEqual(P('c:a/.hg.rc').suffixes, ['.rc'])
        self.assertEqual(P('c:/a/.hg.rc').suffixes, ['.rc'])
        self.assertEqual(P('c:a/b.tar.gz').suffixes, ['.tar', '.gz'])
        self.assertEqual(P('c:/a/b.tar.gz').suffixes, ['.tar', '.gz'])
        self.assertEqual(P('//My.py/Share.php').suffixes, [])
        self.assertEqual(P('//My.py/Share.php/a/b').suffixes, [])
        self.assertEqual(P('c:a/Some name. Ending with a dot.').suffixes, [])
        self.assertEqual(P('c:/a/Some name. Ending with a dot.').suffixes, [])

    def test_stem(self):
        P = self.cls
        self.assertEqual(P('c:').stem, '')
        self.assertEqual(P('c:.').stem, '')
        self.assertEqual(P('c:..').stem, '..')
        self.assertEqual(P('c:/').stem, '')
        self.assertEqual(P('c:a/b').stem, 'b')
        self.assertEqual(P('c:a/b.py').stem, 'b')
        self.assertEqual(P('c:a/.hgrc').stem, '.hgrc')
        self.assertEqual(P('c:a/.hg.rc').stem, '.hg')
        self.assertEqual(P('c:a/b.tar.gz').stem, 'b.tar')
        self.assertEqual(P('c:a/Some name. Ending with a dot.').stem,
                         'Some name. Ending with a dot.')

    def test_with_name(self):
        P = self.cls
        self.assertEqual(P('c:a/b').with_name('d.xml'), P('c:a/d.xml'))
        self.assertEqual(P('c:/a/b').with_name('d.xml'), P('c:/a/d.xml'))
        self.assertEqual(P('c:a/Dot ending.').with_name('d.xml'), P('c:a/d.xml'))
        self.assertEqual(P('c:/a/Dot ending.').with_name('d.xml'), P('c:/a/d.xml'))
        self.assertRaises(ValueError, P('c:').with_name, 'd.xml')
        self.assertRaises(ValueError, P('c:/').with_name, 'd.xml')
        self.assertRaises(ValueError, P('//My/Share').with_name, 'd.xml')
        self.assertRaises(ValueError, P('c:a/b').with_name, 'd:')
        self.assertRaises(ValueError, P('c:a/b').with_name, 'd:e')
        self.assertRaises(ValueError, P('c:a/b').with_name, 'd:/e')
        self.assertRaises(ValueError, P('c:a/b').with_name, '//My/Share')

    def test_with_stem(self):
        P = self.cls
        self.assertEqual(P('c:a/b').with_stem('d'), P('c:a/d'))
        self.assertEqual(P('c:/a/b').with_stem('d'), P('c:/a/d'))
        self.assertEqual(P('c:a/Dot ending.').with_stem('d'), P('c:a/d'))
        self.assertEqual(P('c:/a/Dot ending.').with_stem('d'), P('c:/a/d'))
        self.assertRaises(ValueError, P('c:').with_stem, 'd')
        self.assertRaises(ValueError, P('c:/').with_stem, 'd')
        self.assertRaises(ValueError, P('//My/Share').with_stem, 'd')
        self.assertRaises(ValueError, P('c:a/b').with_stem, 'd:')
        self.assertRaises(ValueError, P('c:a/b').with_stem, 'd:e')
        self.assertRaises(ValueError, P('c:a/b').with_stem, 'd:/e')
        self.assertRaises(ValueError, P('c:a/b').with_stem, '//My/Share')

    def test_with_suffix(self):
        P = self.cls
        self.assertEqual(P('c:a/b').with_suffix('.gz'), P('c:a/b.gz'))
        self.assertEqual(P('c:/a/b').with_suffix('.gz'), P('c:/a/b.gz'))
        self.assertEqual(P('c:a/b.py').with_suffix('.gz'), P('c:a/b.gz'))
        self.assertEqual(P('c:/a/b.py').with_suffix('.gz'), P('c:/a/b.gz'))
        # Path doesn't have a "filename" component.
        self.assertRaises(ValueError, P('').with_suffix, '.gz')
        self.assertRaises(ValueError, P('.').with_suffix, '.gz')
        self.assertRaises(ValueError, P('/').with_suffix, '.gz')
        self.assertRaises(ValueError, P('//My/Share').with_suffix, '.gz')
        # Invalid suffix.
        self.assertRaises(ValueError, P('c:a/b').with_suffix, 'gz')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '/')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '\\')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, 'c:')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '/.gz')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '\\.gz')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, 'c:.gz')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, 'c/d')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, 'c\\d')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '.c/d')
        self.assertRaises(ValueError, P('c:a/b').with_suffix, '.c\\d')

    def test_relative_to(self):
        P = self.cls
        p = P('C:Foo/Bar')
        self.assertEqual(p.relative_to(P('c:')), P('Foo/Bar'))
        self.assertEqual(p.relative_to('c:'), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('c:foO')), P('Bar'))
        self.assertEqual(p.relative_to('c:foO'), P('Bar'))
        self.assertEqual(p.relative_to('c:foO/'), P('Bar'))
        self.assertEqual(p.relative_to(P('c:foO/baR')), P())
        self.assertEqual(p.relative_to('c:foO/baR'), P())
        self.assertEqual(p.relative_to(P('c:'), walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to('c:', walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('c:foO'), walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('c:foO', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('c:foO/', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to(P('c:foO/baR'), walk_up=True), P())
        self.assertEqual(p.relative_to('c:foO/baR', walk_up=True), P())
        self.assertEqual(p.relative_to(P('C:Foo/Bar/Baz'), walk_up=True), P('..'))
        self.assertEqual(p.relative_to(P('C:Foo/Baz'), walk_up=True), P('../Bar'))
        self.assertEqual(p.relative_to(P('C:Baz/Bar'), walk_up=True), P('../../Foo/Bar'))
        # Unrelated paths.
        self.assertRaises(ValueError, p.relative_to, P())
        self.assertRaises(ValueError, p.relative_to, '')
        self.assertRaises(ValueError, p.relative_to, P('d:'))
        self.assertRaises(ValueError, p.relative_to, P('/'))
        self.assertRaises(ValueError, p.relative_to, P('Foo'))
        self.assertRaises(ValueError, p.relative_to, P('/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('C:/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('C:Foo/Bar/Baz'))
        self.assertRaises(ValueError, p.relative_to, P('C:Foo/Baz'))
        self.assertRaises(ValueError, p.relative_to, P(), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, '', walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('d:'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('/'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('/Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('C:/Foo'), walk_up=True)
        p = P('C:/Foo/Bar')
        self.assertEqual(p.relative_to(P('c:/')), P('Foo/Bar'))
        self.assertEqual(p.relative_to('c:/'), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('c:/foO')), P('Bar'))
        self.assertEqual(p.relative_to('c:/foO'), P('Bar'))
        self.assertEqual(p.relative_to('c:/foO/'), P('Bar'))
        self.assertEqual(p.relative_to(P('c:/foO/baR')), P())
        self.assertEqual(p.relative_to('c:/foO/baR'), P())
        self.assertEqual(p.relative_to(P('c:/'), walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to('c:/', walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('c:/foO'), walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('c:/foO', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('c:/foO/', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to(P('c:/foO/baR'), walk_up=True), P())
        self.assertEqual(p.relative_to('c:/foO/baR', walk_up=True), P())
        self.assertEqual(p.relative_to('C:/Baz', walk_up=True), P('../Foo/Bar'))
        self.assertEqual(p.relative_to('C:/Foo/Bar/Baz', walk_up=True), P('..'))
        self.assertEqual(p.relative_to('C:/Foo/Baz', walk_up=True), P('../Bar'))
        # Unrelated paths.
        self.assertRaises(ValueError, p.relative_to, 'c:')
        self.assertRaises(ValueError, p.relative_to, P('c:'))
        self.assertRaises(ValueError, p.relative_to, P('C:/Baz'))
        self.assertRaises(ValueError, p.relative_to, P('C:/Foo/Bar/Baz'))
        self.assertRaises(ValueError, p.relative_to, P('C:/Foo/Baz'))
        self.assertRaises(ValueError, p.relative_to, P('C:Foo'))
        self.assertRaises(ValueError, p.relative_to, P('d:'))
        self.assertRaises(ValueError, p.relative_to, P('d:/'))
        self.assertRaises(ValueError, p.relative_to, P('/'))
        self.assertRaises(ValueError, p.relative_to, P('/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('//C/Foo'))
        self.assertRaises(ValueError, p.relative_to, 'c:', walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('c:'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('C:Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('d:'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('d:/'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('/'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('/Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('//C/Foo'), walk_up=True)
        # UNC paths.
        p = P('//Server/Share/Foo/Bar')
        self.assertEqual(p.relative_to(P('//sErver/sHare')), P('Foo/Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare'), P('Foo/Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/'), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('//sErver/sHare/Foo')), P('Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/Foo'), P('Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/Foo/'), P('Bar'))
        self.assertEqual(p.relative_to(P('//sErver/sHare/Foo/Bar')), P())
        self.assertEqual(p.relative_to('//sErver/sHare/Foo/Bar'), P())
        self.assertEqual(p.relative_to(P('//sErver/sHare'), walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare', walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/', walk_up=True), P('Foo/Bar'))
        self.assertEqual(p.relative_to(P('//sErver/sHare/Foo'), walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/Foo', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/Foo/', walk_up=True), P('Bar'))
        self.assertEqual(p.relative_to(P('//sErver/sHare/Foo/Bar'), walk_up=True), P())
        self.assertEqual(p.relative_to('//sErver/sHare/Foo/Bar', walk_up=True), P())
        self.assertEqual(p.relative_to(P('//sErver/sHare/bar'), walk_up=True), P('../Foo/Bar'))
        self.assertEqual(p.relative_to('//sErver/sHare/bar', walk_up=True), P('../Foo/Bar'))
        # Unrelated paths.
        self.assertRaises(ValueError, p.relative_to, P('/Server/Share/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('c:/Server/Share/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('//z/Share/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('//Server/z/Foo'))
        self.assertRaises(ValueError, p.relative_to, P('/Server/Share/Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('c:/Server/Share/Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('//z/Share/Foo'), walk_up=True)
        self.assertRaises(ValueError, p.relative_to, P('//Server/z/Foo'), walk_up=True)

    def test_is_relative_to(self):
        P = self.cls
        p = P('C:Foo/Bar')
        self.assertTrue(p.is_relative_to(P('c:')))
        self.assertTrue(p.is_relative_to('c:'))
        self.assertTrue(p.is_relative_to(P('c:foO')))
        self.assertTrue(p.is_relative_to('c:foO'))
        self.assertTrue(p.is_relative_to('c:foO/'))
        self.assertTrue(p.is_relative_to(P('c:foO/baR')))
        self.assertTrue(p.is_relative_to('c:foO/baR'))
        # Unrelated paths.
        self.assertFalse(p.is_relative_to(P()))
        self.assertFalse(p.is_relative_to(''))
        self.assertFalse(p.is_relative_to(P('d:')))
        self.assertFalse(p.is_relative_to(P('/')))
        self.assertFalse(p.is_relative_to(P('Foo')))
        self.assertFalse(p.is_relative_to(P('/Foo')))
        self.assertFalse(p.is_relative_to(P('C:/Foo')))
        self.assertFalse(p.is_relative_to(P('C:Foo/Bar/Baz')))
        self.assertFalse(p.is_relative_to(P('C:Foo/Baz')))
        p = P('C:/Foo/Bar')
        self.assertTrue(p.is_relative_to(P('c:/')))
        self.assertTrue(p.is_relative_to(P('c:/foO')))
        self.assertTrue(p.is_relative_to('c:/foO/'))
        self.assertTrue(p.is_relative_to(P('c:/foO/baR')))
        self.assertTrue(p.is_relative_to('c:/foO/baR'))
        # Unrelated paths.
        self.assertFalse(p.is_relative_to('c:'))
        self.assertFalse(p.is_relative_to(P('C:/Baz')))
        self.assertFalse(p.is_relative_to(P('C:/Foo/Bar/Baz')))
        self.assertFalse(p.is_relative_to(P('C:/Foo/Baz')))
        self.assertFalse(p.is_relative_to(P('C:Foo')))
        self.assertFalse(p.is_relative_to(P('d:')))
        self.assertFalse(p.is_relative_to(P('d:/')))
        self.assertFalse(p.is_relative_to(P('/')))
        self.assertFalse(p.is_relative_to(P('/Foo')))
        self.assertFalse(p.is_relative_to(P('//C/Foo')))
        # UNC paths.
        p = P('//Server/Share/Foo/Bar')
        self.assertTrue(p.is_relative_to(P('//sErver/sHare')))
        self.assertTrue(p.is_relative_to('//sErver/sHare'))
        self.assertTrue(p.is_relative_to('//sErver/sHare/'))
        self.assertTrue(p.is_relative_to(P('//sErver/sHare/Foo')))
        self.assertTrue(p.is_relative_to('//sErver/sHare/Foo'))
        self.assertTrue(p.is_relative_to('//sErver/sHare/Foo/'))
        self.assertTrue(p.is_relative_to(P('//sErver/sHare/Foo/Bar')))
        self.assertTrue(p.is_relative_to('//sErver/sHare/Foo/Bar'))
        # Unrelated paths.
        self.assertFalse(p.is_relative_to(P('/Server/Share/Foo')))
        self.assertFalse(p.is_relative_to(P('c:/Server/Share/Foo')))
        self.assertFalse(p.is_relative_to(P('//z/Share/Foo')))
        self.assertFalse(p.is_relative_to(P('//Server/z/Foo')))

    def test_is_absolute(self):
        P = self.cls
        # Under NT, only paths with both a drive and a root are absolute.
        self.assertFalse(P().is_absolute())
        self.assertFalse(P('a').is_absolute())
        self.assertFalse(P('a/b/').is_absolute())
        self.assertFalse(P('/').is_absolute())
        self.assertFalse(P('/a').is_absolute())
        self.assertFalse(P('/a/b/').is_absolute())
        self.assertFalse(P('c:').is_absolute())
        self.assertFalse(P('c:a').is_absolute())
        self.assertFalse(P('c:a/b/').is_absolute())
        self.assertTrue(P('c:/').is_absolute())
        self.assertTrue(P('c:/a').is_absolute())
        self.assertTrue(P('c:/a/b/').is_absolute())
        # UNC paths are absolute by definition.
        self.assertTrue(P('//a/b').is_absolute())
        self.assertTrue(P('//a/b/').is_absolute())
        self.assertTrue(P('//a/b/c').is_absolute())
        self.assertTrue(P('//a/b/c/d').is_absolute())

    def test_join(self):
        P = self.cls
        p = P('C:/a/b')
        pp = p.joinpath('x/y')
        self.assertEqual(pp, P('C:/a/b/x/y'))
        pp = p.joinpath('/x/y')
        self.assertEqual(pp, P('C:/x/y'))
        # Joining with a different drive => the first path is ignored, even
        # if the second path is relative.
        pp = p.joinpath('D:x/y')
        self.assertEqual(pp, P('D:x/y'))
        pp = p.joinpath('D:/x/y')
        self.assertEqual(pp, P('D:/x/y'))
        pp = p.joinpath('//host/share/x/y')
        self.assertEqual(pp, P('//host/share/x/y'))
        # Joining with the same drive => the first path is appended to if
        # the second path is relative.
        pp = p.joinpath('c:x/y')
        self.assertEqual(pp, P('C:/a/b/x/y'))
        pp = p.joinpath('c:/x/y')
        self.assertEqual(pp, P('C:/x/y'))
        # Joining with files with NTFS data streams => the filename should
        # not be parsed as a drive letter
        pp = p.joinpath(P('./d:s'))
        self.assertEqual(pp, P('C:/a/b/d:s'))
        pp = p.joinpath(P('./dd:s'))
        self.assertEqual(pp, P('C:/a/b/dd:s'))
        pp = p.joinpath(P('E:d:s'))
        self.assertEqual(pp, P('E:d:s'))
        # Joining onto a UNC path with no root
        pp = P('//').joinpath('server')
        self.assertEqual(pp, P('//server'))
        pp = P('//server').joinpath('share')
        self.assertEqual(pp, P('//server/share'))
        pp = P('//./BootPartition').joinpath('Windows')
        self.assertEqual(pp, P('//./BootPartition/Windows'))

    def test_div(self):
        # Basically the same as joinpath().
        P = self.cls
        p = P('C:/a/b')
        self.assertEqual(p / 'x/y', P('C:/a/b/x/y'))
        self.assertEqual(p / 'x' / 'y', P('C:/a/b/x/y'))
        self.assertEqual(p / '/x/y', P('C:/x/y'))
        self.assertEqual(p / '/x' / 'y', P('C:/x/y'))
        # Joining with a different drive => the first path is ignored, even
        # if the second path is relative.
        self.assertEqual(p / 'D:x/y', P('D:x/y'))
        self.assertEqual(p / 'D:' / 'x/y', P('D:x/y'))
        self.assertEqual(p / 'D:/x/y', P('D:/x/y'))
        self.assertEqual(p / 'D:' / '/x/y', P('D:/x/y'))
        self.assertEqual(p / '//host/share/x/y', P('//host/share/x/y'))
        # Joining with the same drive => the first path is appended to if
        # the second path is relative.
        self.assertEqual(p / 'c:x/y', P('C:/a/b/x/y'))
        self.assertEqual(p / 'c:/x/y', P('C:/x/y'))
        # Joining with files with NTFS data streams => the filename should
        # not be parsed as a drive letter
        self.assertEqual(p / P('./d:s'), P('C:/a/b/d:s'))
        self.assertEqual(p / P('./dd:s'), P('C:/a/b/dd:s'))
        self.assertEqual(p / P('E:d:s'), P('E:d:s'))

    def test_is_reserved(self):
        P = self.cls
        self.assertIs(False, P('').is_reserved())
        self.assertIs(False, P('/').is_reserved())
        self.assertIs(False, P('/foo/bar').is_reserved())
        # UNC paths are never reserved.
        self.assertIs(False, P('//my/share/nul/con/aux').is_reserved())
        # Case-insensitive DOS-device names are reserved.
        self.assertIs(True, P('nul').is_reserved())
        self.assertIs(True, P('aux').is_reserved())
        self.assertIs(True, P('prn').is_reserved())
        self.assertIs(True, P('con').is_reserved())
        self.assertIs(True, P('conin$').is_reserved())
        self.assertIs(True, P('conout$').is_reserved())
        # COM/LPT + 1-9 or + superscript 1-3 are reserved.
        self.assertIs(True, P('COM1').is_reserved())
        self.assertIs(True, P('LPT9').is_reserved())
        self.assertIs(True, P('com\xb9').is_reserved())
        self.assertIs(True, P('com\xb2').is_reserved())
        self.assertIs(True, P('lpt\xb3').is_reserved())
        # DOS-device name mataching ignores characters after a dot or
        # a colon and also ignores trailing spaces.
        self.assertIs(True, P('NUL.txt').is_reserved())
        self.assertIs(True, P('PRN  ').is_reserved())
        self.assertIs(True, P('AUX  .txt').is_reserved())
        self.assertIs(True, P('COM1:bar').is_reserved())
        self.assertIs(True, P('LPT9   :bar').is_reserved())
        # DOS-device names are only matched at the beginning
        # of a path component.
        self.assertIs(False, P('bar.com9').is_reserved())
        self.assertIs(False, P('bar.lpt9').is_reserved())
        # Only the last path component matters.
        self.assertIs(True, P('c:/baz/con/NUL').is_reserved())
        self.assertIs(False, P('c:/NUL/con/baz').is_reserved())


class PurePathSubclassTest(PurePathTest):
    class cls(pathlib.PurePath):
        pass

    # repr() roundtripping is not supported in custom subclass.
    test_repr_roundtrips = None


@only_posix
class PosixPathAsPureTest(PurePosixPathTest):
    cls = pathlib.PosixPath

@only_nt
class WindowsPathAsPureTest(PureWindowsPathTest):
    cls = pathlib.WindowsPath

    def test_owner(self):
        P = self.cls
        with self.assertRaises(pathlib.UnsupportedOperation):
            P('c:/').owner()

    def test_group(self):
        P = self.cls
        with self.assertRaises(pathlib.UnsupportedOperation):
            P('c:/').group()


#
# Tests for the concrete classes.
#

class PathTest(unittest.TestCase):
    """Tests for the FS-accessing functionalities of the Path classes."""

    cls = pathlib.Path
    can_symlink = os_helper.can_symlink()

    # (BASE)
    #  |
    #  |-- brokenLink -> non-existing
    #  |-- dirA
    #  |   `-- linkC -> ../dirB
    #  |-- dirB
    #  |   |-- fileB
    #  |   `-- linkD -> ../dirB
    #  |-- dirC
    #  |   |-- dirD
    #  |   |   `-- fileD
    #  |   `-- fileC
    #  |   `-- novel.txt
    #  |-- dirE  # No permissions
    #  |-- fileA
    #  |-- linkA -> fileA
    #  |-- linkB -> dirB
    #  `-- brokenLinkLoop -> brokenLinkLoop
    #

    def setUp(self):
        def cleanup():
            os.chmod(join('dirE'), 0o777)
            os_helper.rmtree(BASE)
        self.addCleanup(cleanup)
        os.mkdir(BASE)
        os.mkdir(join('dirA'))
        os.mkdir(join('dirB'))
        os.mkdir(join('dirC'))
        os.mkdir(join('dirC', 'dirD'))
        os.mkdir(join('dirE'))
        with open(join('fileA'), 'wb') as f:
            f.write(b"this is file A\n")
        with open(join('dirB', 'fileB'), 'wb') as f:
            f.write(b"this is file B\n")
        with open(join('dirC', 'fileC'), 'wb') as f:
            f.write(b"this is file C\n")
        with open(join('dirC', 'novel.txt'), 'wb') as f:
            f.write(b"this is a novel\n")
        with open(join('dirC', 'dirD', 'fileD'), 'wb') as f:
            f.write(b"this is file D\n")
        os.chmod(join('dirE'), 0)
        if self.can_symlink:
            # Relative symlinks.
            os.symlink('fileA', join('linkA'))
            os.symlink('non-existing', join('brokenLink'))
            os.symlink('dirB', join('linkB'), target_is_directory=True)
            os.symlink(os.path.join('..', 'dirB'), join('dirA', 'linkC'), target_is_directory=True)
            # This one goes upwards, creating a loop.
            os.symlink(os.path.join('..', 'dirB'), join('dirB', 'linkD'), target_is_directory=True)
            # Broken symlink (pointing to itself).
            os.symlink('brokenLinkLoop',  join('brokenLinkLoop'))

    def assertFileNotFound(self, func, *args, **kwargs):
        with self.assertRaises(FileNotFoundError) as cm:
            func(*args, **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENOENT)

    def assertEqualNormCase(self, path_a, path_b):
        self.assertEqual(os.path.normcase(path_a), os.path.normcase(path_b))

    def test_samefile(self):
        fileA_path = os.path.join(BASE, 'fileA')
        fileB_path = os.path.join(BASE, 'dirB', 'fileB')
        p = self.cls(fileA_path)
        pp = self.cls(fileA_path)
        q = self.cls(fileB_path)
        self.assertTrue(p.samefile(fileA_path))
        self.assertTrue(p.samefile(pp))
        self.assertFalse(p.samefile(fileB_path))
        self.assertFalse(p.samefile(q))
        # Test the non-existent file case
        non_existent = os.path.join(BASE, 'foo')
        r = self.cls(non_existent)
        self.assertRaises(FileNotFoundError, p.samefile, r)
        self.assertRaises(FileNotFoundError, p.samefile, non_existent)
        self.assertRaises(FileNotFoundError, r.samefile, p)
        self.assertRaises(FileNotFoundError, r.samefile, non_existent)
        self.assertRaises(FileNotFoundError, r.samefile, r)
        self.assertRaises(FileNotFoundError, r.samefile, non_existent)

    def test_empty_path(self):
        # The empty path points to '.'
        p = self.cls('')
        self.assertEqual(str(p), '.')

    def test_exists(self):
        P = self.cls
        p = P(BASE)
        self.assertIs(True, p.exists())
        self.assertIs(True, (p / 'dirA').exists())
        self.assertIs(True, (p / 'fileA').exists())
        self.assertIs(False, (p / 'fileA' / 'bah').exists())
        if self.can_symlink:
            self.assertIs(True, (p / 'linkA').exists())
            self.assertIs(True, (p / 'linkB').exists())
            self.assertIs(True, (p / 'linkB' / 'fileB').exists())
            self.assertIs(False, (p / 'linkA' / 'bah').exists())
            self.assertIs(False, (p / 'brokenLink').exists())
            self.assertIs(True, (p / 'brokenLink').exists(follow_symlinks=False))
        self.assertIs(False, (p / 'foo').exists())
        self.assertIs(False, P('/xyzzy').exists())
        self.assertIs(False, P(BASE + '\udfff').exists())
        self.assertIs(False, P(BASE + '\x00').exists())

    def test_open_common(self):
        p = self.cls(BASE)
        with (p / 'fileA').open('r') as f:
            self.assertIsInstance(f, io.TextIOBase)
            self.assertEqual(f.read(), "this is file A\n")
        with (p / 'fileA').open('rb') as f:
            self.assertIsInstance(f, io.BufferedIOBase)
            self.assertEqual(f.read().strip(), b"this is file A")

    def test_read_write_bytes(self):
        p = self.cls(BASE)
        (p / 'fileA').write_bytes(b'abcdefg')
        self.assertEqual((p / 'fileA').read_bytes(), b'abcdefg')
        # Check that trying to write str does not truncate the file.
        self.assertRaises(TypeError, (p / 'fileA').write_bytes, 'somestr')
        self.assertEqual((p / 'fileA').read_bytes(), b'abcdefg')

    def test_read_write_text(self):
        p = self.cls(BASE)
        (p / 'fileA').write_text('äbcdefg', encoding='latin-1')
        self.assertEqual((p / 'fileA').read_text(
            encoding='utf-8', errors='ignore'), 'bcdefg')
        # Check that trying to write bytes does not truncate the file.
        self.assertRaises(TypeError, (p / 'fileA').write_text, b'somebytes')
        self.assertEqual((p / 'fileA').read_text(encoding='latin-1'), 'äbcdefg')

    def test_write_text_with_newlines(self):
        p = self.cls(BASE)
        # Check that `\n` character change nothing
        (p / 'fileA').write_text('abcde\r\nfghlk\n\rmnopq', newline='\n')
        self.assertEqual((p / 'fileA').read_bytes(),
                         b'abcde\r\nfghlk\n\rmnopq')
        # Check that `\r` character replaces `\n`
        (p / 'fileA').write_text('abcde\r\nfghlk\n\rmnopq', newline='\r')
        self.assertEqual((p / 'fileA').read_bytes(),
                         b'abcde\r\rfghlk\r\rmnopq')
        # Check that `\r\n` character replaces `\n`
        (p / 'fileA').write_text('abcde\r\nfghlk\n\rmnopq', newline='\r\n')
        self.assertEqual((p / 'fileA').read_bytes(),
                         b'abcde\r\r\nfghlk\r\n\rmnopq')
        # Check that no argument passed will change `\n` to `os.linesep`
        os_linesep_byte = bytes(os.linesep, encoding='ascii')
        (p / 'fileA').write_text('abcde\nfghlk\n\rmnopq')
        self.assertEqual((p / 'fileA').read_bytes(),
                          b'abcde' + os_linesep_byte + b'fghlk' + os_linesep_byte + b'\rmnopq')

    def test_iterdir(self):
        P = self.cls
        p = P(BASE)
        it = p.iterdir()
        paths = set(it)
        expected = ['dirA', 'dirB', 'dirC', 'dirE', 'fileA']
        if self.can_symlink:
            expected += ['linkA', 'linkB', 'brokenLink', 'brokenLinkLoop']
        self.assertEqual(paths, { P(BASE, q) for q in expected })

    def test_iterdir_symlink(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        # __iter__ on a symlink to a directory.
        P = self.cls
        p = P(BASE, 'linkB')
        paths = set(p.iterdir())
        expected = { P(BASE, 'linkB', q) for q in ['fileB', 'linkD'] }
        self.assertEqual(paths, expected)

    def test_iterdir_nodir(self):
        # __iter__ on something that is not a directory.
        p = self.cls(BASE, 'fileA')
        with self.assertRaises(OSError) as cm:
            next(p.iterdir())
        # ENOENT or EINVAL under Windows, ENOTDIR otherwise
        # (see issue #12802).
        self.assertIn(cm.exception.errno, (errno.ENOTDIR,
                                           errno.ENOENT, errno.EINVAL))

    def test_glob_common(self):
        def _check(glob, expected):
            self.assertEqual(set(glob), { P(BASE, q) for q in expected })
        P = self.cls
        p = P(BASE)
        it = p.glob("fileA")
        self.assertIsInstance(it, collections.abc.Iterator)
        _check(it, ["fileA"])
        _check(p.glob("fileB"), [])
        _check(p.glob("dir*/file*"), ["dirB/fileB", "dirC/fileC"])
        if not self.can_symlink:
            _check(p.glob("*A"), ['dirA', 'fileA'])
        else:
            _check(p.glob("*A"), ['dirA', 'fileA', 'linkA'])
        if not self.can_symlink:
            _check(p.glob("*B/*"), ['dirB/fileB'])
        else:
            _check(p.glob("*B/*"), ['dirB/fileB', 'dirB/linkD',
                                    'linkB/fileB', 'linkB/linkD'])
        if not self.can_symlink:
            _check(p.glob("*/fileB"), ['dirB/fileB'])
        else:
            _check(p.glob("*/fileB"), ['dirB/fileB', 'linkB/fileB'])
        if self.can_symlink:
            _check(p.glob("brokenLink"), ['brokenLink'])

        if not self.can_symlink:
            _check(p.glob("*/"), ["dirA", "dirB", "dirC", "dirE"])
        else:
            _check(p.glob("*/"), ["dirA", "dirB", "dirC", "dirE", "linkB"])

    def test_glob_empty_pattern(self):
        p = self.cls()
        with self.assertRaisesRegex(ValueError, 'Unacceptable pattern'):
            list(p.glob(''))

    def test_glob_case_sensitive(self):
        P = self.cls
        def _check(path, pattern, case_sensitive, expected):
            actual = {str(q) for q in path.glob(pattern, case_sensitive=case_sensitive)}
            expected = {str(P(BASE, q)) for q in expected}
            self.assertEqual(actual, expected)
        path = P(BASE)
        _check(path, "DIRB/FILE*", True, [])
        _check(path, "DIRB/FILE*", False, ["dirB/fileB"])
        _check(path, "dirb/file*", True, [])
        _check(path, "dirb/file*", False, ["dirB/fileB"])

    def test_glob_follow_symlinks_common(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        def _check(path, glob, expected):
            actual = {path for path in path.glob(glob, follow_symlinks=True)
                      if "linkD" not in path.parent.parts}  # exclude symlink loop.
            self.assertEqual(actual, { P(BASE, q) for q in expected })
        P = self.cls
        p = P(BASE)
        _check(p, "fileB", [])
        _check(p, "dir*/file*", ["dirB/fileB", "dirC/fileC"])
        _check(p, "*A", ["dirA", "fileA", "linkA"])
        _check(p, "*B/*", ["dirB/fileB", "dirB/linkD", "linkB/fileB", "linkB/linkD"])
        _check(p, "*/fileB", ["dirB/fileB", "linkB/fileB"])
        _check(p, "*/", ["dirA", "dirB", "dirC", "dirE", "linkB"])
        _check(p, "dir*/*/..", ["dirC/dirD/..", "dirA/linkC/.."])
        _check(p, "dir*/**/", ["dirA", "dirA/linkC", "dirA/linkC/linkD", "dirB", "dirB/linkD",
                                 "dirC", "dirC/dirD", "dirE"])
        _check(p, "dir*/**/..", ["dirA/..", "dirA/linkC/..", "dirB/..",
                                 "dirC/..", "dirC/dirD/..", "dirE/.."])
        _check(p, "dir*/*/**/", ["dirA/linkC", "dirA/linkC/linkD", "dirB/linkD", "dirC/dirD"])
        _check(p, "dir*/*/**/..", ["dirA/linkC/..", "dirC/dirD/.."])
        _check(p, "dir*/**/fileC", ["dirC/fileC"])
        _check(p, "dir*/*/../dirD/**/", ["dirC/dirD/../dirD"])
        _check(p, "*/dirD/**/", ["dirC/dirD"])

    def test_glob_no_follow_symlinks_common(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        def _check(path, glob, expected):
            actual = {path for path in path.glob(glob, follow_symlinks=False)}
            self.assertEqual(actual, { P(BASE, q) for q in expected })
        P = self.cls
        p = P(BASE)
        _check(p, "fileB", [])
        _check(p, "dir*/file*", ["dirB/fileB", "dirC/fileC"])
        _check(p, "*A", ["dirA", "fileA", "linkA"])
        _check(p, "*B/*", ["dirB/fileB", "dirB/linkD"])
        _check(p, "*/fileB", ["dirB/fileB"])
        _check(p, "*/", ["dirA", "dirB", "dirC", "dirE"])
        _check(p, "dir*/*/..", ["dirC/dirD/.."])
        _check(p, "dir*/**/", ["dirA", "dirB", "dirC", "dirC/dirD", "dirE"])
        _check(p, "dir*/**/..", ["dirA/..", "dirB/..", "dirC/..", "dirC/dirD/..", "dirE/.."])
        _check(p, "dir*/*/**/", ["dirC/dirD"])
        _check(p, "dir*/*/**/..", ["dirC/dirD/.."])
        _check(p, "dir*/**/fileC", ["dirC/fileC"])
        _check(p, "dir*/*/../dirD/**/", ["dirC/dirD/../dirD"])
        _check(p, "*/dirD/**/", ["dirC/dirD"])

    def test_rglob_common(self):
        def _check(glob, expected):
            self.assertEqual(sorted(glob), sorted(P(BASE, q) for q in expected))
        P = self.cls
        p = P(BASE)
        it = p.rglob("fileA")
        self.assertIsInstance(it, collections.abc.Iterator)
        _check(it, ["fileA"])
        _check(p.rglob("fileB"), ["dirB/fileB"])
        _check(p.rglob("**/fileB"), ["dirB/fileB"])
        _check(p.rglob("*/fileA"), [])
        if not self.can_symlink:
            _check(p.rglob("*/fileB"), ["dirB/fileB"])
        else:
            _check(p.rglob("*/fileB"), ["dirB/fileB", "dirB/linkD/fileB",
                                        "linkB/fileB", "dirA/linkC/fileB"])
        _check(p.rglob("file*"), ["fileA", "dirB/fileB",
                                  "dirC/fileC", "dirC/dirD/fileD"])
        if not self.can_symlink:
            _check(p.rglob("*/"), [
                "dirA", "dirB", "dirC", "dirC/dirD", "dirE",
            ])
        else:
            _check(p.rglob("*/"), [
                "dirA", "dirA/linkC", "dirB", "dirB/linkD", "dirC",
                "dirC/dirD", "dirE", "linkB",
            ])
        _check(p.rglob(""), ["", "dirA", "dirB", "dirC", "dirE", "dirC/dirD"])

        p = P(BASE, "dirC")
        _check(p.rglob("*"), ["dirC/fileC", "dirC/novel.txt",
                              "dirC/dirD", "dirC/dirD/fileD"])
        _check(p.rglob("file*"), ["dirC/fileC", "dirC/dirD/fileD"])
        _check(p.rglob("**/file*"), ["dirC/fileC", "dirC/dirD/fileD"])
        _check(p.rglob("dir*/**"), ["dirC/dirD"])
        _check(p.rglob("*/*"), ["dirC/dirD/fileD"])
        _check(p.rglob("*/"), ["dirC/dirD"])
        _check(p.rglob(""), ["dirC", "dirC/dirD"])
        _check(p.rglob("**"), ["dirC", "dirC/dirD"])
        # gh-91616, a re module regression
        _check(p.rglob("*.txt"), ["dirC/novel.txt"])
        _check(p.rglob("*.*"), ["dirC/novel.txt"])

    def test_rglob_follow_symlinks_common(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        def _check(path, glob, expected):
            actual = {path for path in path.rglob(glob, follow_symlinks=True)
                      if 'linkD' not in path.parent.parts}  # exclude symlink loop.
            self.assertEqual(actual, { P(BASE, q) for q in expected })
        P = self.cls
        p = P(BASE)
        _check(p, "fileB", ["dirB/fileB", "dirA/linkC/fileB", "linkB/fileB"])
        _check(p, "*/fileA", [])
        _check(p, "*/fileB", ["dirB/fileB", "dirA/linkC/fileB", "linkB/fileB"])
        _check(p, "file*", ["fileA", "dirA/linkC/fileB", "dirB/fileB",
                            "dirC/fileC", "dirC/dirD/fileD", "linkB/fileB"])
        _check(p, "*/", ["dirA", "dirA/linkC", "dirA/linkC/linkD", "dirB", "dirB/linkD",
                         "dirC", "dirC/dirD", "dirE", "linkB", "linkB/linkD"])
        _check(p, "", ["", "dirA", "dirA/linkC", "dirA/linkC/linkD", "dirB", "dirB/linkD",
                       "dirC", "dirE", "dirC/dirD", "linkB", "linkB/linkD"])

        p = P(BASE, "dirC")
        _check(p, "*", ["dirC/fileC", "dirC/novel.txt",
                        "dirC/dirD", "dirC/dirD/fileD"])
        _check(p, "file*", ["dirC/fileC", "dirC/dirD/fileD"])
        _check(p, "*/*", ["dirC/dirD/fileD"])
        _check(p, "*/", ["dirC/dirD"])
        _check(p, "", ["dirC", "dirC/dirD"])
        # gh-91616, a re module regression
        _check(p, "*.txt", ["dirC/novel.txt"])
        _check(p, "*.*", ["dirC/novel.txt"])

    def test_rglob_no_follow_symlinks_common(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        def _check(path, glob, expected):
            actual = {path for path in path.rglob(glob, follow_symlinks=False)}
            self.assertEqual(actual, { P(BASE, q) for q in expected })
        P = self.cls
        p = P(BASE)
        _check(p, "fileB", ["dirB/fileB"])
        _check(p, "*/fileA", [])
        _check(p, "*/fileB", ["dirB/fileB"])
        _check(p, "file*", ["fileA", "dirB/fileB", "dirC/fileC", "dirC/dirD/fileD", ])
        _check(p, "*/", ["dirA", "dirB", "dirC", "dirC/dirD", "dirE"])
        _check(p, "", ["", "dirA", "dirB", "dirC", "dirE", "dirC/dirD"])

        p = P(BASE, "dirC")
        _check(p, "*", ["dirC/fileC", "dirC/novel.txt",
                        "dirC/dirD", "dirC/dirD/fileD"])
        _check(p, "file*", ["dirC/fileC", "dirC/dirD/fileD"])
        _check(p, "*/*", ["dirC/dirD/fileD"])
        _check(p, "*/", ["dirC/dirD"])
        _check(p, "", ["dirC", "dirC/dirD"])
        # gh-91616, a re module regression
        _check(p, "*.txt", ["dirC/novel.txt"])
        _check(p, "*.*", ["dirC/novel.txt"])

    def test_rglob_symlink_loop(self):
        # Don't get fooled by symlink loops (Issue #26012).
        if not self.can_symlink:
            self.skipTest("symlinks required")
        P = self.cls
        p = P(BASE)
        given = set(p.rglob('*'))
        expect = {'brokenLink',
                  'dirA', 'dirA/linkC',
                  'dirB', 'dirB/fileB', 'dirB/linkD',
                  'dirC', 'dirC/dirD', 'dirC/dirD/fileD',
                  'dirC/fileC', 'dirC/novel.txt',
                  'dirE',
                  'fileA',
                  'linkA',
                  'linkB',
                  'brokenLinkLoop',
                  }
        self.assertEqual(given, {p / x for x in expect})

    def test_glob_many_open_files(self):
        depth = 30
        P = self.cls
        base = P(BASE) / 'deep'
        p = P(base, *(['d']*depth))
        p.mkdir(parents=True)
        pattern = '/'.join(['*'] * depth)
        iters = [base.glob(pattern) for j in range(100)]
        for it in iters:
            self.assertEqual(next(it), p)
        iters = [base.rglob('d') for j in range(100)]
        p = base
        for i in range(depth):
            p = p / 'd'
            for it in iters:
                self.assertEqual(next(it), p)

    def test_glob_dotdot(self):
        # ".." is not special in globs.
        P = self.cls
        p = P(BASE)
        self.assertEqual(set(p.glob("..")), { P(BASE, "..") })
        self.assertEqual(set(p.glob("../..")), { P(BASE, "..", "..") })
        self.assertEqual(set(p.glob("dirA/..")), { P(BASE, "dirA", "..") })
        self.assertEqual(set(p.glob("dirA/../file*")), { P(BASE, "dirA/../fileA") })
        self.assertEqual(set(p.glob("dirA/../file*/..")), set())
        self.assertEqual(set(p.glob("../xyzzy")), set())
        self.assertEqual(set(p.glob("xyzzy/..")), set())
        self.assertEqual(set(p.glob("/".join([".."] * 50))), { P(BASE, *[".."] * 50)})

    def test_glob_permissions(self):
        # See bpo-38894
        if not self.can_symlink:
            self.skipTest("symlinks required")
        P = self.cls
        base = P(BASE) / 'permissions'
        base.mkdir()

        for i in range(100):
            link = base / f"link{i}"
            if i % 2:
                link.symlink_to(P(BASE, "dirE", "nonexistent"))
            else:
                link.symlink_to(P(BASE, "dirC"))

        self.assertEqual(len(set(base.glob("*"))), 100)
        self.assertEqual(len(set(base.glob("*/"))), 50)
        self.assertEqual(len(set(base.glob("*/fileC"))), 50)
        self.assertEqual(len(set(base.glob("*/file*"))), 50)

    def test_glob_long_symlink(self):
        # See gh-87695
        if not self.can_symlink:
            self.skipTest("symlinks required")
        base = self.cls(BASE) / 'long_symlink'
        base.mkdir()
        bad_link = base / 'bad_link'
        bad_link.symlink_to("bad" * 200)
        self.assertEqual(sorted(base.glob('**/*')), [bad_link])

    def test_glob_above_recursion_limit(self):
        recursion_limit = 50
        # directory_depth > recursion_limit
        directory_depth = recursion_limit + 10
        base = self.cls(BASE, 'deep')
        path = self.cls(base, *(['d'] * directory_depth))
        path.mkdir(parents=True)

        with set_recursion_limit(recursion_limit):
            list(base.glob('**'))

    def test_readlink(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        P = self.cls(BASE)
        self.assertEqual((P / 'linkA').readlink(), self.cls('fileA'))
        self.assertEqual((P / 'brokenLink').readlink(),
                         self.cls('non-existing'))
        self.assertEqual((P / 'linkB').readlink(), self.cls('dirB'))
        with self.assertRaises(OSError):
            (P / 'fileA').readlink()

    @unittest.skipIf(hasattr(os, "readlink"), "os.readlink() is present")
    def test_readlink_unsupported(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        with self.assertRaises(pathlib.UnsupportedOperation):
            q.readlink(p)

    def _check_resolve(self, p, expected, strict=True):
        q = p.resolve(strict)
        self.assertEqual(q, expected)

    # This can be used to check both relative and absolute resolutions.
    _check_resolve_relative = _check_resolve_absolute = _check_resolve

    def test_resolve_common(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        P = self.cls
        p = P(BASE, 'foo')
        with self.assertRaises(OSError) as cm:
            p.resolve(strict=True)
        self.assertEqual(cm.exception.errno, errno.ENOENT)
        # Non-strict
        self.assertEqualNormCase(str(p.resolve(strict=False)),
                                 os.path.join(BASE, 'foo'))
        p = P(BASE, 'foo', 'in', 'spam')
        self.assertEqualNormCase(str(p.resolve(strict=False)),
                                 os.path.join(BASE, 'foo', 'in', 'spam'))
        p = P(BASE, '..', 'foo', 'in', 'spam')
        self.assertEqualNormCase(str(p.resolve(strict=False)),
                                 os.path.abspath(os.path.join('foo', 'in', 'spam')))
        # These are all relative symlinks.
        p = P(BASE, 'dirB', 'fileB')
        self._check_resolve_relative(p, p)
        p = P(BASE, 'linkA')
        self._check_resolve_relative(p, P(BASE, 'fileA'))
        p = P(BASE, 'dirA', 'linkC', 'fileB')
        self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB'))
        p = P(BASE, 'dirB', 'linkD', 'fileB')
        self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB'))
        # Non-strict
        p = P(BASE, 'dirA', 'linkC', 'fileB', 'foo', 'in', 'spam')
        self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB', 'foo', 'in',
                                          'spam'), False)
        p = P(BASE, 'dirA', 'linkC', '..', 'foo', 'in', 'spam')
        if os.name == 'nt':
            # In Windows, if linkY points to dirB, 'dirA\linkY\..'
            # resolves to 'dirA' without resolving linkY first.
            self._check_resolve_relative(p, P(BASE, 'dirA', 'foo', 'in',
                                              'spam'), False)
        else:
            # In Posix, if linkY points to dirB, 'dirA/linkY/..'
            # resolves to 'dirB/..' first before resolving to parent of dirB.
            self._check_resolve_relative(p, P(BASE, 'foo', 'in', 'spam'), False)
        # Now create absolute symlinks.
        d = os_helper._longpath(tempfile.mkdtemp(suffix='-dirD',
                                                 dir=os.getcwd()))
        self.addCleanup(os_helper.rmtree, d)
        P(BASE, 'dirA', 'linkX').symlink_to(d)
        P(BASE, str(d), 'linkY').symlink_to(join('dirB'))
        p = P(BASE, 'dirA', 'linkX', 'linkY', 'fileB')
        self._check_resolve_absolute(p, P(BASE, 'dirB', 'fileB'))
        # Non-strict
        p = P(BASE, 'dirA', 'linkX', 'linkY', 'foo', 'in', 'spam')
        self._check_resolve_relative(p, P(BASE, 'dirB', 'foo', 'in', 'spam'),
                                     False)
        p = P(BASE, 'dirA', 'linkX', 'linkY', '..', 'foo', 'in', 'spam')
        if os.name == 'nt':
            # In Windows, if linkY points to dirB, 'dirA\linkY\..'
            # resolves to 'dirA' without resolving linkY first.
            self._check_resolve_relative(p, P(d, 'foo', 'in', 'spam'), False)
        else:
            # In Posix, if linkY points to dirB, 'dirA/linkY/..'
            # resolves to 'dirB/..' first before resolving to parent of dirB.
            self._check_resolve_relative(p, P(BASE, 'foo', 'in', 'spam'), False)

    def test_resolve_dot(self):
        # See http://web.archive.org/web/20200623062557/https://bitbucket.org/pitrou/pathlib/issues/9/
        if not self.can_symlink:
            self.skipTest("symlinks required")
        p = self.cls(BASE)
        p.joinpath('0').symlink_to('.', target_is_directory=True)
        p.joinpath('1').symlink_to(os.path.join('0', '0'), target_is_directory=True)
        p.joinpath('2').symlink_to(os.path.join('1', '1'), target_is_directory=True)
        q = p / '2'
        self.assertEqual(q.resolve(strict=True), p)
        r = q / '3' / '4'
        self.assertRaises(FileNotFoundError, r.resolve, strict=True)
        # Non-strict
        self.assertEqual(r.resolve(strict=False), p / '3' / '4')

    def test_stat(self):
        statA = self.cls(BASE).joinpath('fileA').stat()
        statB = self.cls(BASE).joinpath('dirB', 'fileB').stat()
        statC = self.cls(BASE).joinpath('dirC').stat()
        # st_mode: files are the same, directory differs.
        self.assertIsInstance(statA.st_mode, int)
        self.assertEqual(statA.st_mode, statB.st_mode)
        self.assertNotEqual(statA.st_mode, statC.st_mode)
        self.assertNotEqual(statB.st_mode, statC.st_mode)
        # st_ino: all different,
        self.assertIsInstance(statA.st_ino, int)
        self.assertNotEqual(statA.st_ino, statB.st_ino)
        self.assertNotEqual(statA.st_ino, statC.st_ino)
        self.assertNotEqual(statB.st_ino, statC.st_ino)
        # st_dev: all the same.
        self.assertIsInstance(statA.st_dev, int)
        self.assertEqual(statA.st_dev, statB.st_dev)
        self.assertEqual(statA.st_dev, statC.st_dev)
        # other attributes not used by pathlib.

    def test_stat_no_follow_symlinks(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        p = self.cls(BASE) / 'linkA'
        st = p.stat()
        self.assertNotEqual(st, p.stat(follow_symlinks=False))

    def test_stat_no_follow_symlinks_nosymlink(self):
        p = self.cls(BASE) / 'fileA'
        st = p.stat()
        self.assertEqual(st, p.stat(follow_symlinks=False))

    def test_lstat(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        p = self.cls(BASE)/ 'linkA'
        st = p.stat()
        self.assertNotEqual(st, p.lstat())

    def test_lstat_nosymlink(self):
        p = self.cls(BASE) / 'fileA'
        st = p.stat()
        self.assertEqual(st, p.lstat())

    def test_is_dir(self):
        P = self.cls(BASE)
        self.assertTrue((P / 'dirA').is_dir())
        self.assertFalse((P / 'fileA').is_dir())
        self.assertFalse((P / 'non-existing').is_dir())
        self.assertFalse((P / 'fileA' / 'bah').is_dir())
        if self.can_symlink:
            self.assertFalse((P / 'linkA').is_dir())
            self.assertTrue((P / 'linkB').is_dir())
            self.assertFalse((P/ 'brokenLink').is_dir())
        self.assertFalse((P / 'dirA\udfff').is_dir())
        self.assertFalse((P / 'dirA\x00').is_dir())

    def test_is_dir_no_follow_symlinks(self):
        P = self.cls(BASE)
        self.assertTrue((P / 'dirA').is_dir(follow_symlinks=False))
        self.assertFalse((P / 'fileA').is_dir(follow_symlinks=False))
        self.assertFalse((P / 'non-existing').is_dir(follow_symlinks=False))
        self.assertFalse((P / 'fileA' / 'bah').is_dir(follow_symlinks=False))
        if self.can_symlink:
            self.assertFalse((P / 'linkA').is_dir(follow_symlinks=False))
            self.assertFalse((P / 'linkB').is_dir(follow_symlinks=False))
            self.assertFalse((P/ 'brokenLink').is_dir(follow_symlinks=False))
        self.assertFalse((P / 'dirA\udfff').is_dir(follow_symlinks=False))
        self.assertFalse((P / 'dirA\x00').is_dir(follow_symlinks=False))

    def test_is_file(self):
        P = self.cls(BASE)
        self.assertTrue((P / 'fileA').is_file())
        self.assertFalse((P / 'dirA').is_file())
        self.assertFalse((P / 'non-existing').is_file())
        self.assertFalse((P / 'fileA' / 'bah').is_file())
        if self.can_symlink:
            self.assertTrue((P / 'linkA').is_file())
            self.assertFalse((P / 'linkB').is_file())
            self.assertFalse((P/ 'brokenLink').is_file())
        self.assertFalse((P / 'fileA\udfff').is_file())
        self.assertFalse((P / 'fileA\x00').is_file())

    def test_is_file_no_follow_symlinks(self):
        P = self.cls(BASE)
        self.assertTrue((P / 'fileA').is_file(follow_symlinks=False))
        self.assertFalse((P / 'dirA').is_file(follow_symlinks=False))
        self.assertFalse((P / 'non-existing').is_file(follow_symlinks=False))
        self.assertFalse((P / 'fileA' / 'bah').is_file(follow_symlinks=False))
        if self.can_symlink:
            self.assertFalse((P / 'linkA').is_file(follow_symlinks=False))
            self.assertFalse((P / 'linkB').is_file(follow_symlinks=False))
            self.assertFalse((P/ 'brokenLink').is_file(follow_symlinks=False))
        self.assertFalse((P / 'fileA\udfff').is_file(follow_symlinks=False))
        self.assertFalse((P / 'fileA\x00').is_file(follow_symlinks=False))

    def test_is_mount(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_mount())
        self.assertFalse((P / 'dirA').is_mount())
        self.assertFalse((P / 'non-existing').is_mount())
        self.assertFalse((P / 'fileA' / 'bah').is_mount())
        if self.can_symlink:
            self.assertFalse((P / 'linkA').is_mount())

    def test_is_symlink(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_symlink())
        self.assertFalse((P / 'dirA').is_symlink())
        self.assertFalse((P / 'non-existing').is_symlink())
        self.assertFalse((P / 'fileA' / 'bah').is_symlink())
        if self.can_symlink:
            self.assertTrue((P / 'linkA').is_symlink())
            self.assertTrue((P / 'linkB').is_symlink())
            self.assertTrue((P/ 'brokenLink').is_symlink())
        self.assertIs((P / 'fileA\udfff').is_file(), False)
        self.assertIs((P / 'fileA\x00').is_file(), False)
        if self.can_symlink:
            self.assertIs((P / 'linkA\udfff').is_file(), False)
            self.assertIs((P / 'linkA\x00').is_file(), False)

    def test_is_junction_false(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_junction())
        self.assertFalse((P / 'dirA').is_junction())
        self.assertFalse((P / 'non-existing').is_junction())
        self.assertFalse((P / 'fileA' / 'bah').is_junction())
        self.assertFalse((P / 'fileA\udfff').is_junction())
        self.assertFalse((P / 'fileA\x00').is_junction())

    def test_is_fifo_false(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_fifo())
        self.assertFalse((P / 'dirA').is_fifo())
        self.assertFalse((P / 'non-existing').is_fifo())
        self.assertFalse((P / 'fileA' / 'bah').is_fifo())
        self.assertIs((P / 'fileA\udfff').is_fifo(), False)
        self.assertIs((P / 'fileA\x00').is_fifo(), False)

    def test_is_socket_false(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_socket())
        self.assertFalse((P / 'dirA').is_socket())
        self.assertFalse((P / 'non-existing').is_socket())
        self.assertFalse((P / 'fileA' / 'bah').is_socket())
        self.assertIs((P / 'fileA\udfff').is_socket(), False)
        self.assertIs((P / 'fileA\x00').is_socket(), False)

    def test_is_block_device_false(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_block_device())
        self.assertFalse((P / 'dirA').is_block_device())
        self.assertFalse((P / 'non-existing').is_block_device())
        self.assertFalse((P / 'fileA' / 'bah').is_block_device())
        self.assertIs((P / 'fileA\udfff').is_block_device(), False)
        self.assertIs((P / 'fileA\x00').is_block_device(), False)

    def test_is_char_device_false(self):
        P = self.cls(BASE)
        self.assertFalse((P / 'fileA').is_char_device())
        self.assertFalse((P / 'dirA').is_char_device())
        self.assertFalse((P / 'non-existing').is_char_device())
        self.assertFalse((P / 'fileA' / 'bah').is_char_device())
        self.assertIs((P / 'fileA\udfff').is_char_device(), False)
        self.assertIs((P / 'fileA\x00').is_char_device(), False)

    def test_pickling_common(self):
        p = self.cls(BASE, 'fileA')
        for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
            dumped = pickle.dumps(p, proto)
            pp = pickle.loads(dumped)
            self.assertEqual(pp.stat(), p.stat())

    def test_parts_interning(self):
        P = self.cls
        p = P('/usr/bin/foo')
        q = P('/usr/local/bin')
        # 'usr'
        self.assertIs(p.parts[1], q.parts[1])
        # 'bin'
        self.assertIs(p.parts[2], q.parts[3])

    def _check_complex_symlinks(self, link0_target):
        if not self.can_symlink:
            self.skipTest("symlinks required")

        # Test solving a non-looping chain of symlinks (issue #19887).
        P = self.cls(BASE)
        P.joinpath('link1').symlink_to(os.path.join('link0', 'link0'), target_is_directory=True)
        P.joinpath('link2').symlink_to(os.path.join('link1', 'link1'), target_is_directory=True)
        P.joinpath('link3').symlink_to(os.path.join('link2', 'link2'), target_is_directory=True)
        P.joinpath('link0').symlink_to(link0_target, target_is_directory=True)

        # Resolve absolute paths.
        p = (P / 'link0').resolve()
        self.assertEqual(p, P)
        self.assertEqualNormCase(str(p), BASE)
        p = (P / 'link1').resolve()
        self.assertEqual(p, P)
        self.assertEqualNormCase(str(p), BASE)
        p = (P / 'link2').resolve()
        self.assertEqual(p, P)
        self.assertEqualNormCase(str(p), BASE)
        p = (P / 'link3').resolve()
        self.assertEqual(p, P)
        self.assertEqualNormCase(str(p), BASE)

        # Resolve relative paths.
        old_path = os.getcwd()
        os.chdir(BASE)
        try:
            p = self.cls('link0').resolve()
            self.assertEqual(p, P)
            self.assertEqualNormCase(str(p), BASE)
            p = self.cls('link1').resolve()
            self.assertEqual(p, P)
            self.assertEqualNormCase(str(p), BASE)
            p = self.cls('link2').resolve()
            self.assertEqual(p, P)
            self.assertEqualNormCase(str(p), BASE)
            p = self.cls('link3').resolve()
            self.assertEqual(p, P)
            self.assertEqualNormCase(str(p), BASE)
        finally:
            os.chdir(old_path)

    def test_complex_symlinks_absolute(self):
        self._check_complex_symlinks(BASE)

    def test_complex_symlinks_relative(self):
        self._check_complex_symlinks('.')

    def test_complex_symlinks_relative_dot_dot(self):
        self._check_complex_symlinks(os.path.join('dirA', '..'))

    def test_concrete_class(self):
        if self.cls is pathlib.Path:
            expected = pathlib.WindowsPath if os.name == 'nt' else pathlib.PosixPath
        else:
            expected = self.cls
        p = self.cls('a')
        self.assertIs(type(p), expected)

    def test_unsupported_flavour(self):
        if self.cls._flavour is os.path:
            self.skipTest("path flavour is supported")
        else:
            self.assertRaises(pathlib.UnsupportedOperation, self.cls)

    def _test_cwd(self, p):
        q = self.cls(os.getcwd())
        self.assertEqual(p, q)
        self.assertEqualNormCase(str(p), str(q))
        self.assertIs(type(p), type(q))
        self.assertTrue(p.is_absolute())

    def test_cwd(self):
        p = self.cls.cwd()
        self._test_cwd(p)

    def test_absolute_common(self):
        P = self.cls

        with mock.patch("os.getcwd") as getcwd:
            getcwd.return_value = BASE

            # Simple relative paths.
            self.assertEqual(str(P().absolute()), BASE)
            self.assertEqual(str(P('.').absolute()), BASE)
            self.assertEqual(str(P('a').absolute()), os.path.join(BASE, 'a'))
            self.assertEqual(str(P('a', 'b', 'c').absolute()), os.path.join(BASE, 'a', 'b', 'c'))

            # Symlinks should not be resolved.
            self.assertEqual(str(P('linkB', 'fileB').absolute()), os.path.join(BASE, 'linkB', 'fileB'))
            self.assertEqual(str(P('brokenLink').absolute()), os.path.join(BASE, 'brokenLink'))
            self.assertEqual(str(P('brokenLinkLoop').absolute()), os.path.join(BASE, 'brokenLinkLoop'))

            # '..' entries should be preserved and not normalised.
            self.assertEqual(str(P('..').absolute()), os.path.join(BASE, '..'))
            self.assertEqual(str(P('a', '..').absolute()), os.path.join(BASE, 'a', '..'))
            self.assertEqual(str(P('..', 'b').absolute()), os.path.join(BASE, '..', 'b'))

    def _test_home(self, p):
        q = self.cls(os.path.expanduser('~'))
        self.assertEqual(p, q)
        self.assertEqualNormCase(str(p), str(q))
        self.assertIs(type(p), type(q))
        self.assertTrue(p.is_absolute())

    @unittest.skipIf(
        pwd is None, reason="Test requires pwd module to get homedir."
    )
    def test_home(self):
        with os_helper.EnvironmentVarGuard() as env:
            self._test_home(self.cls.home())

            env.clear()
            env['USERPROFILE'] = os.path.join(BASE, 'userprofile')
            self._test_home(self.cls.home())

            # bpo-38883: ignore `HOME` when set on windows
            env['HOME'] = os.path.join(BASE, 'home')
            self._test_home(self.cls.home())

    @unittest.skipIf(is_wasi, "WASI has no user accounts.")
    def test_expanduser_common(self):
        P = self.cls
        p = P('~')
        self.assertEqual(p.expanduser(), P(os.path.expanduser('~')))
        p = P('foo')
        self.assertEqual(p.expanduser(), p)
        p = P('/~')
        self.assertEqual(p.expanduser(), p)
        p = P('../~')
        self.assertEqual(p.expanduser(), p)
        p = P(P('').absolute().anchor) / '~'
        self.assertEqual(p.expanduser(), p)
        p = P('~/a:b')
        self.assertEqual(p.expanduser(), P(os.path.expanduser('~'), './a:b'))

    def test_with_segments(self):
        class P(self.cls):
            def __init__(self, *pathsegments, session_id):
                super().__init__(*pathsegments)
                self.session_id = session_id

            def with_segments(self, *pathsegments):
                return type(self)(*pathsegments, session_id=self.session_id)
        p = P(BASE, session_id=42)
        self.assertEqual(42, p.absolute().session_id)
        self.assertEqual(42, p.resolve().session_id)
        if not is_wasi:  # WASI has no user accounts.
            self.assertEqual(42, p.with_segments('~').expanduser().session_id)
        self.assertEqual(42, (p / 'fileA').rename(p / 'fileB').session_id)
        self.assertEqual(42, (p / 'fileB').replace(p / 'fileA').session_id)
        if self.can_symlink:
            self.assertEqual(42, (p / 'linkA').readlink().session_id)
        for path in p.iterdir():
            self.assertEqual(42, path.session_id)
        for path in p.glob('*'):
            self.assertEqual(42, path.session_id)
        for path in p.rglob('*'):
            self.assertEqual(42, path.session_id)
        for dirpath, dirnames, filenames in p.walk():
            self.assertEqual(42, dirpath.session_id)

    def test_open_unbuffered(self):
        p = self.cls(BASE)
        with (p / 'fileA').open('rb', buffering=0) as f:
            self.assertIsInstance(f, io.RawIOBase)
            self.assertEqual(f.read().strip(), b"this is file A")

    def test_resolve_nonexist_relative_issue38671(self):
        p = self.cls('non', 'exist')

        old_cwd = os.getcwd()
        os.chdir(BASE)
        try:
            self.assertEqual(p.resolve(), self.cls(BASE, p))
        finally:
            os.chdir(old_cwd)

    @os_helper.skip_unless_working_chmod
    def test_chmod(self):
        p = self.cls(BASE) / 'fileA'
        mode = p.stat().st_mode
        # Clear writable bit.
        new_mode = mode & ~0o222
        p.chmod(new_mode)
        self.assertEqual(p.stat().st_mode, new_mode)
        # Set writable bit.
        new_mode = mode | 0o222
        p.chmod(new_mode)
        self.assertEqual(p.stat().st_mode, new_mode)

    # On Windows, os.chmod does not follow symlinks (issue #15411)
    @only_posix
    @os_helper.skip_unless_working_chmod
    def test_chmod_follow_symlinks_true(self):
        p = self.cls(BASE) / 'linkA'
        q = p.resolve()
        mode = q.stat().st_mode
        # Clear writable bit.
        new_mode = mode & ~0o222
        p.chmod(new_mode, follow_symlinks=True)
        self.assertEqual(q.stat().st_mode, new_mode)
        # Set writable bit
        new_mode = mode | 0o222
        p.chmod(new_mode, follow_symlinks=True)
        self.assertEqual(q.stat().st_mode, new_mode)

    # XXX also need a test for lchmod.

    @unittest.skipUnless(pwd, "the pwd module is needed for this test")
    def test_owner(self):
        p = self.cls(BASE) / 'fileA'
        uid = p.stat().st_uid
        try:
            name = pwd.getpwuid(uid).pw_name
        except KeyError:
            self.skipTest(
                "user %d doesn't have an entry in the system database" % uid)
        self.assertEqual(name, p.owner())

    @unittest.skipUnless(grp, "the grp module is needed for this test")
    def test_group(self):
        p = self.cls(BASE) / 'fileA'
        gid = p.stat().st_gid
        try:
            name = grp.getgrgid(gid).gr_name
        except KeyError:
            self.skipTest(
                "group %d doesn't have an entry in the system database" % gid)
        self.assertEqual(name, p.group())

    def test_unlink(self):
        p = self.cls(BASE) / 'fileA'
        p.unlink()
        self.assertFileNotFound(p.stat)
        self.assertFileNotFound(p.unlink)

    def test_unlink_missing_ok(self):
        p = self.cls(BASE) / 'fileAAA'
        self.assertFileNotFound(p.unlink)
        p.unlink(missing_ok=True)

    def test_rmdir(self):
        p = self.cls(BASE) / 'dirA'
        for q in p.iterdir():
            q.unlink()
        p.rmdir()
        self.assertFileNotFound(p.stat)
        self.assertFileNotFound(p.unlink)

    @unittest.skipUnless(hasattr(os, "link"), "os.link() is not present")
    def test_hardlink_to(self):
        P = self.cls(BASE)
        target = P / 'fileA'
        size = target.stat().st_size
        # linking to another path.
        link = P / 'dirA' / 'fileAA'
        link.hardlink_to(target)
        self.assertEqual(link.stat().st_size, size)
        self.assertTrue(os.path.samefile(target, link))
        self.assertTrue(target.exists())
        # Linking to a str of a relative path.
        link2 = P / 'dirA' / 'fileAAA'
        target2 = rel_join('fileA')
        link2.hardlink_to(target2)
        self.assertEqual(os.stat(target2).st_size, size)
        self.assertTrue(link2.exists())

    @unittest.skipIf(hasattr(os, "link"), "os.link() is present")
    def test_hardlink_to_unsupported(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        # linking to another path.
        q = P / 'dirA' / 'fileAA'
        with self.assertRaises(pathlib.UnsupportedOperation):
            q.hardlink_to(p)

    def test_rename(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        size = p.stat().st_size
        # Renaming to another path.
        q = P / 'dirA' / 'fileAA'
        renamed_p = p.rename(q)
        self.assertEqual(renamed_p, q)
        self.assertEqual(q.stat().st_size, size)
        self.assertFileNotFound(p.stat)
        # Renaming to a str of a relative path.
        r = rel_join('fileAAA')
        renamed_q = q.rename(r)
        self.assertEqual(renamed_q, self.cls(r))
        self.assertEqual(os.stat(r).st_size, size)
        self.assertFileNotFound(q.stat)

    def test_replace(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        size = p.stat().st_size
        # Replacing a non-existing path.
        q = P / 'dirA' / 'fileAA'
        replaced_p = p.replace(q)
        self.assertEqual(replaced_p, q)
        self.assertEqual(q.stat().st_size, size)
        self.assertFileNotFound(p.stat)
        # Replacing another (existing) path.
        r = rel_join('dirB', 'fileB')
        replaced_q = q.replace(r)
        self.assertEqual(replaced_q, self.cls(r))
        self.assertEqual(os.stat(r).st_size, size)
        self.assertFileNotFound(q.stat)

    def test_touch_common(self):
        P = self.cls(BASE)
        p = P / 'newfileA'
        self.assertFalse(p.exists())
        p.touch()
        self.assertTrue(p.exists())
        st = p.stat()
        old_mtime = st.st_mtime
        old_mtime_ns = st.st_mtime_ns
        # Rewind the mtime sufficiently far in the past to work around
        # filesystem-specific timestamp granularity.
        os.utime(str(p), (old_mtime - 10, old_mtime - 10))
        # The file mtime should be refreshed by calling touch() again.
        p.touch()
        st = p.stat()
        self.assertGreaterEqual(st.st_mtime_ns, old_mtime_ns)
        self.assertGreaterEqual(st.st_mtime, old_mtime)
        # Now with exist_ok=False.
        p = P / 'newfileB'
        self.assertFalse(p.exists())
        p.touch(mode=0o700, exist_ok=False)
        self.assertTrue(p.exists())
        self.assertRaises(OSError, p.touch, exist_ok=False)

    def test_touch_nochange(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        p.touch()
        with p.open('rb') as f:
            self.assertEqual(f.read().strip(), b"this is file A")

    def test_mkdir(self):
        P = self.cls(BASE)
        p = P / 'newdirA'
        self.assertFalse(p.exists())
        p.mkdir()
        self.assertTrue(p.exists())
        self.assertTrue(p.is_dir())
        with self.assertRaises(OSError) as cm:
            p.mkdir()
        self.assertEqual(cm.exception.errno, errno.EEXIST)

    def test_mkdir_parents(self):
        # Creating a chain of directories.
        p = self.cls(BASE, 'newdirB', 'newdirC')
        self.assertFalse(p.exists())
        with self.assertRaises(OSError) as cm:
            p.mkdir()
        self.assertEqual(cm.exception.errno, errno.ENOENT)
        p.mkdir(parents=True)
        self.assertTrue(p.exists())
        self.assertTrue(p.is_dir())
        with self.assertRaises(OSError) as cm:
            p.mkdir(parents=True)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        # Test `mode` arg.
        mode = stat.S_IMODE(p.stat().st_mode)  # Default mode.
        p = self.cls(BASE, 'newdirD', 'newdirE')
        p.mkdir(0o555, parents=True)
        self.assertTrue(p.exists())
        self.assertTrue(p.is_dir())
        if os.name != 'nt':
            # The directory's permissions follow the mode argument.
            self.assertEqual(stat.S_IMODE(p.stat().st_mode), 0o7555 & mode)
        # The parent's permissions follow the default process settings.
        self.assertEqual(stat.S_IMODE(p.parent.stat().st_mode), mode)

    def test_mkdir_exist_ok(self):
        p = self.cls(BASE, 'dirB')
        st_ctime_first = p.stat().st_ctime
        self.assertTrue(p.exists())
        self.assertTrue(p.is_dir())
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir()
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        p.mkdir(exist_ok=True)
        self.assertTrue(p.exists())
        self.assertEqual(p.stat().st_ctime, st_ctime_first)

    def test_mkdir_exist_ok_with_parent(self):
        p = self.cls(BASE, 'dirC')
        self.assertTrue(p.exists())
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir()
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        p = p / 'newdirC'
        p.mkdir(parents=True)
        st_ctime_first = p.stat().st_ctime
        self.assertTrue(p.exists())
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir(parents=True)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        p.mkdir(parents=True, exist_ok=True)
        self.assertTrue(p.exists())
        self.assertEqual(p.stat().st_ctime, st_ctime_first)

    @unittest.skipIf(is_emscripten, "FS root cannot be modified on Emscripten.")
    def test_mkdir_exist_ok_root(self):
        # Issue #25803: A drive root could raise PermissionError on Windows.
        self.cls('/').resolve().mkdir(exist_ok=True)
        self.cls('/').resolve().mkdir(parents=True, exist_ok=True)

    @only_nt  # XXX: not sure how to test this on POSIX.
    def test_mkdir_with_unknown_drive(self):
        for d in 'ZYXWVUTSRQPONMLKJIHGFEDCBA':
            p = self.cls(d + ':\\')
            if not p.is_dir():
                break
        else:
            self.skipTest("cannot find a drive that doesn't exist")
        with self.assertRaises(OSError):
            (p / 'child' / 'path').mkdir(parents=True)

    def test_mkdir_with_child_file(self):
        p = self.cls(BASE, 'dirB', 'fileB')
        self.assertTrue(p.exists())
        # An exception is raised when the last path component is an existing
        # regular file, regardless of whether exist_ok is true or not.
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir(parents=True)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir(parents=True, exist_ok=True)
        self.assertEqual(cm.exception.errno, errno.EEXIST)

    def test_mkdir_no_parents_file(self):
        p = self.cls(BASE, 'fileA')
        self.assertTrue(p.exists())
        # An exception is raised when the last path component is an existing
        # regular file, regardless of whether exist_ok is true or not.
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir()
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        with self.assertRaises(FileExistsError) as cm:
            p.mkdir(exist_ok=True)
        self.assertEqual(cm.exception.errno, errno.EEXIST)

    def test_mkdir_concurrent_parent_creation(self):
        for pattern_num in range(32):
            p = self.cls(BASE, 'dirCPC%d' % pattern_num)
            self.assertFalse(p.exists())

            real_mkdir = os.mkdir
            def my_mkdir(path, mode=0o777):
                path = str(path)
                # Emulate another process that would create the directory
                # just before we try to create it ourselves.  We do it
                # in all possible pattern combinations, assuming that this
                # function is called at most 5 times (dirCPC/dir1/dir2,
                # dirCPC/dir1, dirCPC, dirCPC/dir1, dirCPC/dir1/dir2).
                if pattern.pop():
                    real_mkdir(path, mode)  # From another process.
                    concurrently_created.add(path)
                real_mkdir(path, mode)  # Our real call.

            pattern = [bool(pattern_num & (1 << n)) for n in range(5)]
            concurrently_created = set()
            p12 = p / 'dir1' / 'dir2'
            try:
                with mock.patch("os.mkdir", my_mkdir):
                    p12.mkdir(parents=True, exist_ok=False)
            except FileExistsError:
                self.assertIn(str(p12), concurrently_created)
            else:
                self.assertNotIn(str(p12), concurrently_created)
            self.assertTrue(p.exists())

    def test_symlink_to(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        P = self.cls(BASE)
        target = P / 'fileA'
        # Symlinking a path target.
        link = P / 'dirA' / 'linkAA'
        link.symlink_to(target)
        self.assertEqual(link.stat(), target.stat())
        self.assertNotEqual(link.lstat(), target.stat())
        # Symlinking a str target.
        link = P / 'dirA' / 'linkAAA'
        link.symlink_to(str(target))
        self.assertEqual(link.stat(), target.stat())
        self.assertNotEqual(link.lstat(), target.stat())
        self.assertFalse(link.is_dir())
        # Symlinking to a directory.
        target = P / 'dirB'
        link = P / 'dirA' / 'linkAAAA'
        link.symlink_to(target, target_is_directory=True)
        self.assertEqual(link.stat(), target.stat())
        self.assertNotEqual(link.lstat(), target.stat())
        self.assertTrue(link.is_dir())
        self.assertTrue(list(link.iterdir()))

    @unittest.skipIf(hasattr(os, "symlink"), "os.symlink() is present")
    def test_symlink_to_unsupported(self):
        P = self.cls(BASE)
        p = P / 'fileA'
        # linking to another path.
        q = P / 'dirA' / 'fileAA'
        with self.assertRaises(pathlib.UnsupportedOperation):
            q.symlink_to(p)

    def test_is_junction(self):
        P = self.cls(BASE)

        with mock.patch.object(P._flavour, 'isjunction'):
            self.assertEqual(P.is_junction(), P._flavour.isjunction.return_value)
            P._flavour.isjunction.assert_called_once_with(P)

    @unittest.skipUnless(hasattr(os, "mkfifo"), "os.mkfifo() required")
    @unittest.skipIf(sys.platform == "vxworks",
                    "fifo requires special path on VxWorks")
    def test_is_fifo_true(self):
        P = self.cls(BASE, 'myfifo')
        try:
            os.mkfifo(str(P))
        except PermissionError as e:
            self.skipTest('os.mkfifo(): %s' % e)
        self.assertTrue(P.is_fifo())
        self.assertFalse(P.is_socket())
        self.assertFalse(P.is_file())
        self.assertIs(self.cls(BASE, 'myfifo\udfff').is_fifo(), False)
        self.assertIs(self.cls(BASE, 'myfifo\x00').is_fifo(), False)

    @unittest.skipUnless(hasattr(socket, "AF_UNIX"), "Unix sockets required")
    @unittest.skipIf(
        is_emscripten, "Unix sockets are not implemented on Emscripten."
    )
    @unittest.skipIf(
        is_wasi, "Cannot create socket on WASI."
    )
    def test_is_socket_true(self):
        P = self.cls(BASE, 'mysock')
        sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
        self.addCleanup(sock.close)
        try:
            sock.bind(str(P))
        except OSError as e:
            if (isinstance(e, PermissionError) or
                    "AF_UNIX path too long" in str(e)):
                self.skipTest("cannot bind Unix socket: " + str(e))
        self.assertTrue(P.is_socket())
        self.assertFalse(P.is_fifo())
        self.assertFalse(P.is_file())
        self.assertIs(self.cls(BASE, 'mysock\udfff').is_socket(), False)
        self.assertIs(self.cls(BASE, 'mysock\x00').is_socket(), False)

    def test_is_char_device_true(self):
        # Under Unix, /dev/null should generally be a char device.
        P = self.cls('/dev/null')
        if not P.exists():
            self.skipTest("/dev/null required")
        self.assertTrue(P.is_char_device())
        self.assertFalse(P.is_block_device())
        self.assertFalse(P.is_file())
        self.assertIs(self.cls('/dev/null\udfff').is_char_device(), False)
        self.assertIs(self.cls('/dev/null\x00').is_char_device(), False)

    def test_is_mount_root(self):
        if os.name == 'nt':
            R = self.cls('c:\\')
        else:
            R = self.cls('/')
        self.assertTrue(R.is_mount())
        self.assertFalse((R / '\udfff').is_mount())

    def test_passing_kwargs_deprecated(self):
        with self.assertWarns(DeprecationWarning):
            self.cls(foo="bar")


class WalkTests(unittest.TestCase):

    def setUp(self):
        self.addCleanup(os_helper.rmtree, os_helper.TESTFN)

        # Build:
        #     TESTFN/
        #       TEST1/              a file kid and two directory kids
        #         tmp1
        #         SUB1/             a file kid and a directory kid
        #           tmp2
        #           SUB11/          no kids
        #         SUB2/             a file kid and a dirsymlink kid
        #           tmp3
        #           SUB21/          not readable
        #             tmp5
        #           link/           a symlink to TEST2
        #           broken_link
        #           broken_link2
        #           broken_link3
        #       TEST2/
        #         tmp4              a lone file
        self.walk_path = pathlib.Path(os_helper.TESTFN, "TEST1")
        self.sub1_path = self.walk_path / "SUB1"
        self.sub11_path = self.sub1_path / "SUB11"
        self.sub2_path = self.walk_path / "SUB2"
        sub21_path= self.sub2_path / "SUB21"
        tmp1_path = self.walk_path / "tmp1"
        tmp2_path = self.sub1_path / "tmp2"
        tmp3_path = self.sub2_path / "tmp3"
        tmp5_path = sub21_path / "tmp3"
        self.link_path = self.sub2_path / "link"
        t2_path = pathlib.Path(os_helper.TESTFN, "TEST2")
        tmp4_path = pathlib.Path(os_helper.TESTFN, "TEST2", "tmp4")
        broken_link_path = self.sub2_path / "broken_link"
        broken_link2_path = self.sub2_path / "broken_link2"
        broken_link3_path = self.sub2_path / "broken_link3"

        os.makedirs(self.sub11_path)
        os.makedirs(self.sub2_path)
        os.makedirs(sub21_path)
        os.makedirs(t2_path)

        for path in tmp1_path, tmp2_path, tmp3_path, tmp4_path, tmp5_path:
            with open(path, "x", encoding='utf-8') as f:
                f.write(f"I'm {path} and proud of it.  Blame test_pathlib.\n")

        if os_helper.can_symlink():
            os.symlink(os.path.abspath(t2_path), self.link_path)
            os.symlink('broken', broken_link_path, True)
            os.symlink(pathlib.Path('tmp3', 'broken'), broken_link2_path, True)
            os.symlink(pathlib.Path('SUB21', 'tmp5'), broken_link3_path, True)
            self.sub2_tree = (self.sub2_path, ["SUB21"],
                              ["broken_link", "broken_link2", "broken_link3",
                               "link", "tmp3"])
        else:
            self.sub2_tree = (self.sub2_path, ["SUB21"], ["tmp3"])

        if not is_emscripten:
            # Emscripten fails with inaccessible directories.
            os.chmod(sub21_path, 0)
        try:
            os.listdir(sub21_path)
        except PermissionError:
            self.addCleanup(os.chmod, sub21_path, stat.S_IRWXU)
        else:
            os.chmod(sub21_path, stat.S_IRWXU)
            os.unlink(tmp5_path)
            os.rmdir(sub21_path)
            del self.sub2_tree[1][:1]

    def test_walk_topdown(self):
        walker = self.walk_path.walk()
        entry = next(walker)
        entry[1].sort()  # Ensure we visit SUB1 before SUB2
        self.assertEqual(entry, (self.walk_path, ["SUB1", "SUB2"], ["tmp1"]))
        entry = next(walker)
        self.assertEqual(entry, (self.sub1_path, ["SUB11"], ["tmp2"]))
        entry = next(walker)
        self.assertEqual(entry, (self.sub11_path, [], []))
        entry = next(walker)
        entry[1].sort()
        entry[2].sort()
        self.assertEqual(entry, self.sub2_tree)
        with self.assertRaises(StopIteration):
            next(walker)

    def test_walk_prune(self, walk_path=None):
        if walk_path is None:
            walk_path = self.walk_path
        # Prune the search.
        all = []
        for root, dirs, files in walk_path.walk():
            all.append((root, dirs, files))
            if 'SUB1' in dirs:
                # Note that this also mutates the dirs we appended to all!
                dirs.remove('SUB1')

        self.assertEqual(len(all), 2)
        self.assertEqual(all[0], (self.walk_path, ["SUB2"], ["tmp1"]))

        all[1][-1].sort()
        all[1][1].sort()
        self.assertEqual(all[1], self.sub2_tree)

    def test_file_like_path(self):
        self.test_walk_prune(FakePath(self.walk_path).__fspath__())

    def test_walk_bottom_up(self):
        seen_testfn = seen_sub1 = seen_sub11 = seen_sub2 = False
        for path, dirnames, filenames in self.walk_path.walk(top_down=False):
            if path == self.walk_path:
                self.assertFalse(seen_testfn)
                self.assertTrue(seen_sub1)
                self.assertTrue(seen_sub2)
                self.assertEqual(sorted(dirnames), ["SUB1", "SUB2"])
                self.assertEqual(filenames, ["tmp1"])
                seen_testfn = True
            elif path == self.sub1_path:
                self.assertFalse(seen_testfn)
                self.assertFalse(seen_sub1)
                self.assertTrue(seen_sub11)
                self.assertEqual(dirnames, ["SUB11"])
                self.assertEqual(filenames, ["tmp2"])
                seen_sub1 = True
            elif path == self.sub11_path:
                self.assertFalse(seen_sub1)
                self.assertFalse(seen_sub11)
                self.assertEqual(dirnames, [])
                self.assertEqual(filenames, [])
                seen_sub11 = True
            elif path == self.sub2_path:
                self.assertFalse(seen_testfn)
                self.assertFalse(seen_sub2)
                self.assertEqual(sorted(dirnames), sorted(self.sub2_tree[1]))
                self.assertEqual(sorted(filenames), sorted(self.sub2_tree[2]))
                seen_sub2 = True
            else:
                raise AssertionError(f"Unexpected path: {path}")
        self.assertTrue(seen_testfn)

    @os_helper.skip_unless_symlink
    def test_walk_follow_symlinks(self):
        walk_it = self.walk_path.walk(follow_symlinks=True)
        for root, dirs, files in walk_it:
            if root == self.link_path:
                self.assertEqual(dirs, [])
                self.assertEqual(files, ["tmp4"])
                break
        else:
            self.fail("Didn't follow symlink with follow_symlinks=True")

    @os_helper.skip_unless_symlink
    def test_walk_symlink_location(self):
        # Tests whether symlinks end up in filenames or dirnames depending
        # on the `follow_symlinks` argument.
        walk_it = self.walk_path.walk(follow_symlinks=False)
        for root, dirs, files in walk_it:
            if root == self.sub2_path:
                self.assertIn("link", files)
                break
        else:
            self.fail("symlink not found")

        walk_it = self.walk_path.walk(follow_symlinks=True)
        for root, dirs, files in walk_it:
            if root == self.sub2_path:
                self.assertIn("link", dirs)
                break

    def test_walk_bad_dir(self):
        errors = []
        walk_it = self.walk_path.walk(on_error=errors.append)
        root, dirs, files = next(walk_it)
        self.assertEqual(errors, [])
        dir1 = 'SUB1'
        path1 = root / dir1
        path1new = (root / dir1).with_suffix(".new")
        path1.rename(path1new)
        try:
            roots = [r for r, _, _ in walk_it]
            self.assertTrue(errors)
            self.assertNotIn(path1, roots)
            self.assertNotIn(path1new, roots)
            for dir2 in dirs:
                if dir2 != dir1:
                    self.assertIn(root / dir2, roots)
        finally:
            path1new.rename(path1)

    def test_walk_many_open_files(self):
        depth = 30
        base = pathlib.Path(os_helper.TESTFN, 'deep')
        path = pathlib.Path(base, *(['d']*depth))
        path.mkdir(parents=True)

        iters = [base.walk(top_down=False) for _ in range(100)]
        for i in range(depth + 1):
            expected = (path, ['d'] if i else [], [])
            for it in iters:
                self.assertEqual(next(it), expected)
            path = path.parent

        iters = [base.walk(top_down=True) for _ in range(100)]
        path = base
        for i in range(depth + 1):
            expected = (path, ['d'] if i < depth else [], [])
            for it in iters:
                self.assertEqual(next(it), expected)
            path = path / 'd'

    def test_walk_above_recursion_limit(self):
        recursion_limit = 40
        # directory_depth > recursion_limit
        directory_depth = recursion_limit + 10
        base = pathlib.Path(os_helper.TESTFN, 'deep')
        path = pathlib.Path(base, *(['d'] * directory_depth))
        path.mkdir(parents=True)

        with set_recursion_limit(recursion_limit):
            list(base.walk())
            list(base.walk(top_down=False))


@only_posix
class PosixPathTest(PathTest):
    cls = pathlib.PosixPath

    def test_absolute(self):
        P = self.cls
        self.assertEqual(str(P('/').absolute()), '/')
        self.assertEqual(str(P('/a').absolute()), '/a')
        self.assertEqual(str(P('/a/b').absolute()), '/a/b')

        # '//'-prefixed absolute path (supported by POSIX).
        self.assertEqual(str(P('//').absolute()), '//')
        self.assertEqual(str(P('//a').absolute()), '//a')
        self.assertEqual(str(P('//a/b').absolute()), '//a/b')

    def _check_symlink_loop(self, *args, strict=True):
        path = self.cls(*args)
        with self.assertRaises(RuntimeError):
            print(path.resolve(strict))

    @unittest.skipIf(
        is_emscripten or is_wasi,
        "umask is not implemented on Emscripten/WASI."
    )
    def test_open_mode(self):
        old_mask = os.umask(0)
        self.addCleanup(os.umask, old_mask)
        p = self.cls(BASE)
        with (p / 'new_file').open('wb'):
            pass
        st = os.stat(join('new_file'))
        self.assertEqual(stat.S_IMODE(st.st_mode), 0o666)
        os.umask(0o022)
        with (p / 'other_new_file').open('wb'):
            pass
        st = os.stat(join('other_new_file'))
        self.assertEqual(stat.S_IMODE(st.st_mode), 0o644)

    def test_resolve_root(self):
        current_directory = os.getcwd()
        try:
            os.chdir('/')
            p = self.cls('spam')
            self.assertEqual(str(p.resolve()), '/spam')
        finally:
            os.chdir(current_directory)

    @unittest.skipIf(
        is_emscripten or is_wasi,
        "umask is not implemented on Emscripten/WASI."
    )
    def test_touch_mode(self):
        old_mask = os.umask(0)
        self.addCleanup(os.umask, old_mask)
        p = self.cls(BASE)
        (p / 'new_file').touch()
        st = os.stat(join('new_file'))
        self.assertEqual(stat.S_IMODE(st.st_mode), 0o666)
        os.umask(0o022)
        (p / 'other_new_file').touch()
        st = os.stat(join('other_new_file'))
        self.assertEqual(stat.S_IMODE(st.st_mode), 0o644)
        (p / 'masked_new_file').touch(mode=0o750)
        st = os.stat(join('masked_new_file'))
        self.assertEqual(stat.S_IMODE(st.st_mode), 0o750)

    def test_resolve_loop(self):
        if not self.can_symlink:
            self.skipTest("symlinks required")
        # Loops with relative symlinks.
        os.symlink('linkX/inside', join('linkX'))
        self._check_symlink_loop(BASE, 'linkX')
        os.symlink('linkY', join('linkY'))
        self._check_symlink_loop(BASE, 'linkY')
        os.symlink('linkZ/../linkZ', join('linkZ'))
        self._check_symlink_loop(BASE, 'linkZ')
        # Non-strict
        self._check_symlink_loop(BASE, 'linkZ', 'foo', strict=False)
        # Loops with absolute symlinks.
        os.symlink(join('linkU/inside'), join('linkU'))
        self._check_symlink_loop(BASE, 'linkU')
        os.symlink(join('linkV'), join('linkV'))
        self._check_symlink_loop(BASE, 'linkV')
        os.symlink(join('linkW/../linkW'), join('linkW'))
        self._check_symlink_loop(BASE, 'linkW')
        # Non-strict
        self._check_symlink_loop(BASE, 'linkW', 'foo', strict=False)

    def test_glob(self):
        P = self.cls
        p = P(BASE)
        given = set(p.glob("FILEa"))
        expect = set() if not os_helper.fs_is_case_insensitive(BASE) else given
        self.assertEqual(given, expect)
        self.assertEqual(set(p.glob("FILEa*")), set())

    def test_rglob(self):
        P = self.cls
        p = P(BASE, "dirC")
        given = set(p.rglob("FILEd"))
        expect = set() if not os_helper.fs_is_case_insensitive(BASE) else given
        self.assertEqual(given, expect)
        self.assertEqual(set(p.rglob("FILEd*")), set())

    @unittest.skipUnless(hasattr(pwd, 'getpwall'),
                         'pwd module does not expose getpwall()')
    @unittest.skipIf(sys.platform == "vxworks",
                     "no home directory on VxWorks")
    def test_expanduser(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 '/'
        # Find arbitrary different user (if exists).
        for pwdent in pwd.getpwall():
            othername = pwdent.pw_name
            otherhome = pwdent.pw_dir.rstrip('/')
            if othername != username and otherhome:
                break
        else:
            othername = username
            otherhome = userhome

        fakename = 'fakeuser'
        # This user can theoretically exist on a test runner. Create unique name:
        try:
            while pwd.getpwnam(fakename):
                fakename += '1'
        except KeyError:
            pass  # Non-existent name found

        p1 = P('~/Documents')
        p2 = P(f'~{username}/Documents')
        p3 = P(f'~{othername}/Documents')
        p4 = P(f'../~{username}/Documents')
        p5 = P(f'/~{username}/Documents')
        p6 = P('')
        p7 = P(f'~{fakename}/Documents')

        with os_helper.EnvironmentVarGuard() as env:
            env.pop('HOME', None)

            self.assertEqual(p1.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser)

            env['HOME'] = '/tmp'
            self.assertEqual(p1.expanduser(), P('/tmp/Documents'))
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser)

    @unittest.skipIf(sys.platform != "darwin",
                     "Bad file descriptor in /dev/fd affects only macOS")
    def test_handling_bad_descriptor(self):
        try:
            file_descriptors = list(pathlib.Path('/dev/fd').rglob("*"))[3:]
            if not file_descriptors:
                self.skipTest("no file descriptors - issue was not reproduced")
            # Checking all file descriptors because there is no guarantee
            # which one will fail.
            for f in file_descriptors:
                f.exists()
                f.is_dir()
                f.is_file()
                f.is_symlink()
                f.is_block_device()
                f.is_char_device()
                f.is_fifo()
                f.is_socket()
        except OSError as e:
            if e.errno == errno.EBADF:
                self.fail("Bad file descriptor not handled.")
            raise


@only_nt
class WindowsPathTest(PathTest):
    cls = pathlib.WindowsPath

    def test_absolute(self):
        P = self.cls

        # Simple absolute paths.
        self.assertEqual(str(P('c:\\').absolute()), 'c:\\')
        self.assertEqual(str(P('c:\\a').absolute()), 'c:\\a')
        self.assertEqual(str(P('c:\\a\\b').absolute()), 'c:\\a\\b')

        # UNC absolute paths.
        share = '\\\\server\\share\\'
        self.assertEqual(str(P(share).absolute()), share)
        self.assertEqual(str(P(share + 'a').absolute()), share + 'a')
        self.assertEqual(str(P(share + 'a\\b').absolute()), share + 'a\\b')

        # UNC relative paths.
        with mock.patch("os.getcwd") as getcwd:
            getcwd.return_value = share

            self.assertEqual(str(P().absolute()), share)
            self.assertEqual(str(P('.').absolute()), share)
            self.assertEqual(str(P('a').absolute()), os.path.join(share, 'a'))
            self.assertEqual(str(P('a', 'b', 'c').absolute()),
                             os.path.join(share, 'a', 'b', 'c'))

        drive = os.path.splitdrive(BASE)[0]
        with os_helper.change_cwd(BASE):
            # Relative path with root
            self.assertEqual(str(P('\\').absolute()), drive + '\\')
            self.assertEqual(str(P('\\foo').absolute()), drive + '\\foo')

            # Relative path on current drive
            self.assertEqual(str(P(drive).absolute()), BASE)
            self.assertEqual(str(P(drive + 'foo').absolute()), os.path.join(BASE, 'foo'))

        with os_helper.subst_drive(BASE) as other_drive:
            # Set the working directory on the substitute drive
            saved_cwd = os.getcwd()
            other_cwd = f'{other_drive}\\dirA'
            os.chdir(other_cwd)
            os.chdir(saved_cwd)

            # Relative path on another drive
            self.assertEqual(str(P(other_drive).absolute()), other_cwd)
            self.assertEqual(str(P(other_drive + 'foo').absolute()), other_cwd + '\\foo')

    def test_glob(self):
        P = self.cls
        p = P(BASE)
        self.assertEqual(set(p.glob("FILEa")), { P(BASE, "fileA") })
        self.assertEqual(set(p.glob("*a\\")), { P(BASE, "dirA") })
        self.assertEqual(set(p.glob("F*a")), { P(BASE, "fileA") })
        self.assertEqual(set(map(str, p.glob("FILEa"))), {f"{p}\\fileA"})
        self.assertEqual(set(map(str, p.glob("F*a"))), {f"{p}\\fileA"})

    def test_rglob(self):
        P = self.cls
        p = P(BASE, "dirC")
        self.assertEqual(set(p.rglob("FILEd")), { P(BASE, "dirC/dirD/fileD") })
        self.assertEqual(set(p.rglob("*\\")), { P(BASE, "dirC/dirD") })
        self.assertEqual(set(map(str, p.rglob("FILEd"))), {f"{p}\\dirD\\fileD"})

    def test_expanduser(self):
        P = self.cls
        with os_helper.EnvironmentVarGuard() as env:
            env.pop('HOME', None)
            env.pop('USERPROFILE', None)
            env.pop('HOMEPATH', None)
            env.pop('HOMEDRIVE', None)
            env['USERNAME'] = 'alice'

            # test that the path returns unchanged
            p1 = P('~/My Documents')
            p2 = P('~alice/My Documents')
            p3 = P('~bob/My Documents')
            p4 = P('/~/My Documents')
            p5 = P('d:~/My Documents')
            p6 = P('')
            self.assertRaises(RuntimeError, p1.expanduser)
            self.assertRaises(RuntimeError, p2.expanduser)
            self.assertRaises(RuntimeError, p3.expanduser)
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)

            def check():
                env.pop('USERNAME', None)
                self.assertEqual(p1.expanduser(),
                                 P('C:/Users/alice/My Documents'))
                self.assertRaises(RuntimeError, p2.expanduser)
                env['USERNAME'] = 'alice'
                self.assertEqual(p2.expanduser(),
                                 P('C:/Users/alice/My Documents'))
                self.assertEqual(p3.expanduser(),
                                 P('C:/Users/bob/My Documents'))
                self.assertEqual(p4.expanduser(), p4)
                self.assertEqual(p5.expanduser(), p5)
                self.assertEqual(p6.expanduser(), p6)

            env['HOMEPATH'] = 'C:\\Users\\alice'
            check()

            env['HOMEDRIVE'] = 'C:\\'
            env['HOMEPATH'] = 'Users\\alice'
            check()

            env.pop('HOMEDRIVE', None)
            env.pop('HOMEPATH', None)
            env['USERPROFILE'] = 'C:\\Users\\alice'
            check()

            # bpo-38883: ignore `HOME` when set on windows
            env['HOME'] = 'C:\\Users\\eve'
            check()



class PathSubclassTest(PathTest):
    class cls(pathlib.Path):
        pass

    # repr() roundtripping is not supported in custom subclass.
    test_repr_roundtrips = None


class CompatiblePathTest(unittest.TestCase):
    """
    Test that a type can be made compatible with PurePath
    derivatives by implementing division operator overloads.
    """

    class CompatPath:
        """
        Minimum viable class to test PurePath compatibility.
        Simply uses the division operator to join a given
        string and the string value of another object with
        a forward slash.
        """
        def __init__(self, string):
            self.string = string

        def __truediv__(self, other):
            return type(self)(f"{self.string}/{other}")

        def __rtruediv__(self, other):
            return type(self)(f"{other}/{self.string}")

    def test_truediv(self):
        result = pathlib.PurePath("test") / self.CompatPath("right")
        self.assertIsInstance(result, self.CompatPath)
        self.assertEqual(result.string, "test/right")

        with self.assertRaises(TypeError):
            # Verify improper operations still raise a TypeError
            pathlib.PurePath("test") / 10

    def test_rtruediv(self):
        result = self.CompatPath("left") / pathlib.PurePath("test")
        self.assertIsInstance(result, self.CompatPath)
        self.assertEqual(result.string, "left/test")

        with self.assertRaises(TypeError):
            # Verify improper operations still raise a TypeError
            10 / pathlib.PurePath("test")


if __name__ == "__main__":
    unittest.main()