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Editing: fake_filesystem_shutil.py
# 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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