# Copyright 2009 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""A fake shutil module implementation that uses fake_filesystem for
unit tests.
Note that only `shutildisk_usage()` is faked, the rest of the functions shall
work fine with the fake file system if `os`/`os.path` are patched.
:Includes:
FakeShutil: Uses a FakeFilesystem to provide a fake replacement for the
shutil module.
:Usage:
The fake implementation is automatically involved if using
`fake_filesystem_unittest.TestCase`, pytest fs fixture,
or directly `Patcher`.
"""
import functools
import os
import shutil
import sys
from threading import RLock
from typing import Callable
class FakeShutilModule:
"""Uses a FakeFilesystem to provide a fake replacement
for shutil module.
Automatically created if using `fake_filesystem_unittest.TestCase`,
the `fs` fixture, the `patchfs` decorator, or directly the `Patcher`.
"""
module_lock = RLock()
use_copy_file_range = (
hasattr(shutil, "_USE_CP_COPY_FILE_RANGE") and shutil._USE_CP_COPY_FILE_RANGE # type: ignore[attr-defined]
)
has_fcopy_file = hasattr(shutil, "_HAS_FCOPYFILE") and shutil._HAS_FCOPYFILE # type: ignore[attr-defined]
use_sendfile = hasattr(shutil, "_USE_CP_SENDFILE") and shutil._USE_CP_SENDFILE # type: ignore[attr-defined]
use_fd_functions = shutil._use_fd_functions # type: ignore[attr-defined]
functions_to_patch = ["copy", "copyfile", "rmtree"]
if sys.version_info < (3, 12) or sys.platform != "win32":
functions_to_patch.extend(["copy2", "copytree", "move"])
@staticmethod
def dir():
"""Return the list of patched function names. Used for patching
functions imported from the module.
"""
return ("disk_usage",)
def __init__(self, filesystem):
"""Construct fake shutil module using the fake filesystem.
Args:
filesystem: FakeFilesystem used to provide file system information
"""
self.filesystem = filesystem
self.shutil_module = shutil
self._patch_level = 0
def _start_patching_global_vars(self):
self._patch_level += 1
if self._patch_level > 1:
return # nested call - already patched
if self.has_fcopy_file:
self.shutil_module._HAS_FCOPYFILE = False
if self.use_copy_file_range:
self.shutil_module._USE_CP_COPY_FILE_RANGE = False
if self.use_sendfile:
self.shutil_module._USE_CP_SENDFILE = False
if self.use_fd_functions:
if sys.version_info >= (3, 14):
self.shutil_module._rmtree_impl = (
self.shutil_module._rmtree_unsafe # type: ignore[attr-defined]
)
else:
self.shutil_module._use_fd_functions = False
def _stop_patching_global_vars(self):
self._patch_level -= 1
if self._patch_level > 0:
return # nested call - remains patched
if self.has_fcopy_file:
self.shutil_module._HAS_FCOPYFILE = True
if self.use_copy_file_range:
self.shutil_module._USE_CP_COPY_FILE_RANGE = True
if self.use_sendfile:
self.shutil_module._USE_CP_SENDFILE = True
if self.use_fd_functions:
if sys.version_info >= (3, 14):
self.shutil_module._rmtree_impl = (
self.shutil_module._rmtree_safe_fd # type: ignore[attr-defined]
)
else:
self.shutil_module._use_fd_functions = True
def with_patched_globals(self, f: Callable) -> Callable:
"""Function wrapper that patches global variables during function execution.
Can be used in multi-threading code.
"""
@functools.wraps(f)
def wrapped(*args, **kwargs):
with self.module_lock:
self._start_patching_global_vars()
try:
return f(*args, **kwargs)
finally:
self._stop_patching_global_vars()
return wrapped
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.
Args:
path: defines the filesystem device which is queried
"""
return self.filesystem.get_disk_usage(path)
if sys.version_info >= (3, 12) and sys.platform == "win32":
def copy2(self, src, dst, *, follow_symlinks=True):
"""Since Python 3.12, there is an optimization fow Windows,
using the Windows API. We just remove this and fall back to the previous
implementation.
"""
if self.filesystem.isdir(dst):
dst = self.filesystem.joinpaths(dst, os.path.basename(src))
self.copyfile(src, dst, follow_symlinks=follow_symlinks)
self.copystat(src, dst, follow_symlinks=follow_symlinks)
return dst
def copytree(
self,
src,
dst,
symlinks=False,
ignore=None,
copy_function=shutil.copy2,
ignore_dangling_symlinks=False,
dirs_exist_ok=False,
):
"""Make sure the default argument is patched."""
if copy_function == shutil.copy2:
copy_function = self.copy2
return self.shutil_module.copytree(
src,
dst,
symlinks,
ignore,
copy_function,
ignore_dangling_symlinks,
dirs_exist_ok,
)
def move(self, src, dst, copy_function=shutil.copy2):
"""Make sure the default argument is patched."""
if copy_function == shutil.copy2:
copy_function = self.copy2
return self.shutil_module.move(src, dst, copy_function)
def __getattr__(self, name):
"""Forwards any non-faked calls to the standard shutil module."""
if name in self.functions_to_patch:
return self.with_patched_globals(getattr(self.shutil_module, name))
return getattr(self.shutil_module, name)
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