diff --git a/Doc/library/pathlib.rst b/Doc/library/pathlib.rst index c8a3272d7ba..5bfcad0dadf 100644 --- a/Doc/library/pathlib.rst +++ b/Doc/library/pathlib.rst @@ -1432,17 +1432,26 @@ Creating files and directories Copying, renaming and deleting ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -.. method:: Path.copy(target) +.. method:: Path.copy(target, *, follow_symlinks=True) Copy the contents of this file to the *target* file. If *target* specifies a file that already exists, it will be replaced. + If *follow_symlinks* is false, and this file is a symbolic link, *target* + will be created as a symbolic link. If *follow_symlinks* is true and this + file is a symbolic link, *target* will be a copy of the symlink target. + .. note:: This method uses operating system functionality to copy file content efficiently. The OS might also copy some metadata, such as file permissions. After the copy is complete, users may wish to call :meth:`Path.chmod` to set the permissions of the target file. + .. warning:: + On old builds of Windows (before Windows 10 build 19041), this method + raises :exc:`OSError` when a symlink to a directory is encountered and + *follow_symlinks* is false. + .. versionadded:: 3.14 diff --git a/Lib/pathlib/_abc.py b/Lib/pathlib/_abc.py index 586145ead38..f1f350a1960 100644 --- a/Lib/pathlib/_abc.py +++ b/Lib/pathlib/_abc.py @@ -790,14 +790,19 @@ class PathBase(PurePathBase): """ raise UnsupportedOperation(self._unsupported_msg('mkdir()')) - def copy(self, target): + def copy(self, target, follow_symlinks=True): """ - Copy the contents of this file to the given target. + Copy the contents of this file to the given target. If this file is a + symlink and follow_symlinks is false, a symlink will be created at the + target. """ if not isinstance(target, PathBase): target = self.with_segments(target) if self._samefile_safe(target): raise OSError(f"{self!r} and {target!r} are the same file") + if not follow_symlinks and self.is_symlink(): + target.symlink_to(self.readlink()) + return with self.open('rb') as source_f: try: with target.open('wb') as target_f: diff --git a/Lib/pathlib/_local.py b/Lib/pathlib/_local.py index cffed10dbd1..0105ea30424 100644 --- a/Lib/pathlib/_local.py +++ b/Lib/pathlib/_local.py @@ -782,9 +782,11 @@ class Path(PathBase, PurePath): raise if copyfile: - def copy(self, target): + def copy(self, target, follow_symlinks=True): """ - Copy the contents of this file to the given target. + Copy the contents of this file to the given target. If this file is a + symlink and follow_symlinks is false, a symlink will be created at the + target. """ try: target = os.fspath(target) @@ -792,9 +794,9 @@ class Path(PathBase, PurePath): if isinstance(target, PathBase): # Target is an instance of PathBase but not os.PathLike. # Use generic implementation from PathBase. - return PathBase.copy(self, target) + return PathBase.copy(self, target, follow_symlinks=follow_symlinks) raise - copyfile(os.fspath(self), target) + copyfile(os.fspath(self), target, follow_symlinks) def chmod(self, mode, *, follow_symlinks=True): """ diff --git a/Lib/pathlib/_os.py b/Lib/pathlib/_os.py index 1771d54e416..bbb019b6534 100644 --- a/Lib/pathlib/_os.py +++ b/Lib/pathlib/_os.py @@ -4,6 +4,7 @@ Low-level OS functionality wrappers used by pathlib. from errno import EBADF, EOPNOTSUPP, ETXTBSY, EXDEV import os +import stat import sys try: import fcntl @@ -91,12 +92,32 @@ else: copyfd = None -if _winapi and hasattr(_winapi, 'CopyFile2'): - def copyfile(source, target): +if _winapi and hasattr(_winapi, 'CopyFile2') and hasattr(os.stat_result, 'st_file_attributes'): + def _is_dirlink(path): + try: + st = os.lstat(path) + except (OSError, ValueError): + return False + return (st.st_file_attributes & stat.FILE_ATTRIBUTE_DIRECTORY and + st.st_reparse_tag == stat.IO_REPARSE_TAG_SYMLINK) + + def copyfile(source, target, follow_symlinks): """ Copy from one file to another using CopyFile2 (Windows only). """ - _winapi.CopyFile2(source, target, 0) + if follow_symlinks: + flags = 0 + else: + flags = _winapi.COPY_FILE_COPY_SYMLINK + try: + _winapi.CopyFile2(source, target, flags) + return + except OSError as err: + # Check for ERROR_ACCESS_DENIED + if err.winerror != 5 or not _is_dirlink(source): + raise + flags |= _winapi.COPY_FILE_DIRECTORY + _winapi.CopyFile2(source, target, flags) else: copyfile = None diff --git a/Lib/test/test_pathlib/test_pathlib_abc.py b/Lib/test/test_pathlib/test_pathlib_abc.py index 1c959056c16..cd629c01871 100644 --- a/Lib/test/test_pathlib/test_pathlib_abc.py +++ b/Lib/test/test_pathlib/test_pathlib_abc.py @@ -1743,7 +1743,7 @@ class DummyPathTest(DummyPurePathTest): source.copy(target) @needs_symlinks - def test_copy_symlink(self): + def test_copy_symlink_follow_symlinks_true(self): base = self.cls(self.base) source = base / 'linkA' target = base / 'copyA' @@ -1752,6 +1752,26 @@ class DummyPathTest(DummyPurePathTest): self.assertFalse(target.is_symlink()) self.assertEqual(source.read_text(), target.read_text()) + @needs_symlinks + def test_copy_symlink_follow_symlinks_false(self): + base = self.cls(self.base) + source = base / 'linkA' + target = base / 'copyA' + source.copy(target, follow_symlinks=False) + self.assertTrue(target.exists()) + self.assertTrue(target.is_symlink()) + self.assertEqual(source.readlink(), target.readlink()) + + @needs_symlinks + def test_copy_directory_symlink_follow_symlinks_false(self): + base = self.cls(self.base) + source = base / 'linkB' + target = base / 'copyA' + source.copy(target, follow_symlinks=False) + self.assertTrue(target.exists()) + self.assertTrue(target.is_symlink()) + self.assertEqual(source.readlink(), target.readlink()) + def test_copy_to_existing_file(self): base = self.cls(self.base) source = base / 'fileA' @@ -1780,6 +1800,19 @@ class DummyPathTest(DummyPurePathTest): self.assertFalse(real_target.is_symlink()) self.assertEqual(source.read_text(), real_target.read_text()) + @needs_symlinks + def test_copy_to_existing_symlink_follow_symlinks_false(self): + base = self.cls(self.base) + source = base / 'dirB' / 'fileB' + target = base / 'linkA' + real_target = base / 'fileA' + source.copy(target, follow_symlinks=False) + self.assertTrue(target.exists()) + self.assertTrue(target.is_symlink()) + self.assertTrue(real_target.exists()) + self.assertFalse(real_target.is_symlink()) + self.assertEqual(source.read_text(), real_target.read_text()) + def test_copy_empty(self): base = self.cls(self.base) source = base / 'empty' diff --git a/Modules/_winapi.c b/Modules/_winapi.c index 8794d568e92..c90d6c5a9ef 100644 --- a/Modules/_winapi.c +++ b/Modules/_winapi.c @@ -3166,6 +3166,11 @@ static int winapi_exec(PyObject *m) #define COPY_FILE_REQUEST_COMPRESSED_TRAFFIC 0x10000000 #endif WINAPI_CONSTANT(F_DWORD, COPY_FILE_REQUEST_COMPRESSED_TRAFFIC); +#ifndef COPY_FILE_DIRECTORY + // Only defined in newer WinSDKs + #define COPY_FILE_DIRECTORY 0x00000080 +#endif + WINAPI_CONSTANT(F_DWORD, COPY_FILE_DIRECTORY); WINAPI_CONSTANT(F_DWORD, COPYFILE2_CALLBACK_CHUNK_STARTED); WINAPI_CONSTANT(F_DWORD, COPYFILE2_CALLBACK_CHUNK_FINISHED);