Fix problem with shutil.rmtree if emulating Windows under POSIX

- the fd functions that are used for rmtree are not available under Windows
-> switched of the usage of these function in the fake fs
- fixes pytest-dev#979

CHANGES.md

@@ -23,6 +23,8 @@ The released versions correspond to PyPI releases.
 * fixed handling of `dirfd` in `os.symlink` (see [#968](../../issues/968))
 * add missing `follow_symlink` argument to `os.link` (see [#973](../../issues/973))
 * fixed handling of missing attribute in `os.getxattr` (see [#971](../../issues/971))
+* fixed permission problem with `shutil.rmtree` if emulating Windows under POSIX
+  (see [#979](../../issues/979))
 
 ### Enhancements
 * added support for `O_NOFOLLOW` and `O_DIRECTORY` flags in `os.open`

pyfakefs/fake_filesystem_shutil.py

@@ -53,6 +53,13 @@ def __init__(self, filesystem):
         self.filesystem = filesystem
         self._shutil_module = shutil
 
+    @property
+    def _use_fd_functions(self):
+        print("_use_fd_functions")
+        if self.filesystem.is_windows_fs:
+            return False
+        return self._shutil_module._use_fd_functions
+
     def disk_usage(self, path):
         """Return the total, used and free disk space in bytes as named tuple
         or placeholder holder values simulating unlimited space if not set.

pyfakefs/fake_filesystem_unittest.py

@@ -919,6 +919,10 @@ def setUp(self, doctester: Any = None) -> None:
         if self.has_fcopy_file:
             shutil._HAS_FCOPYFILE = False  # type: ignore[attr-defined]
 
+        # do not use the fd functions, as they may not be available in the target OS
+        if hasattr(shutil, "_use_fd_functions"):
+            shutil._use_fd_functions = False  # type: ignore[module-attr]
+
         with warnings.catch_warnings():
             # ignore warnings, see #542 and #614
             warnings.filterwarnings("ignore")

pyfakefs/tests/fake_filesystem_shutil_test.py

@@ -192,6 +192,15 @@ def error_handler(_, path, _error_info):
         self.assertFalse(NonLocal.errorHandled)
         self.assertEqual(NonLocal.errorPath, "")
 
+    def test_rmtree_in_windows(self):
+        # regression test for #979
+        self.check_windows_only()
+        base_path = self.make_path("foo", "bar")
+        self.os.makedirs(self.os.path.join(base_path, "res"))
+        self.assertTrue(self.os.path.exists(base_path))
+        shutil.rmtree(base_path)
+        self.assertFalse(self.os.path.exists(base_path))
+
     def test_copy(self):
         src_file = self.make_path("xyzzy")
         dst_file = self.make_path("xyzzy_copy")