Add stub for pathlib2 on Python 2.7 (#2351)

pathlib2 is the Python 2.7 backport of the pathlib module from Python 3.
Hence we use the same stub file for both.

The maintainer of pathlib2 granted permission for stubs to be added in
mcmtroffaes/pathlib2#44.

stdlib/3/pathlib.pyi

@@ -1,5 +1,3 @@
-# Stubs for pathlib (Python 3.4)
-
 from typing import Any, Generator, IO, Optional, Sequence, Tuple, Type, TypeVar, Union, List
 from types import TracebackType
 import os

tests/check_consistent.py

@@ -23,6 +23,7 @@ consistent_files = [
     {'stdlib/3/concurrent/futures/thread.pyi', 'third_party/2/concurrent/futures/thread.pyi'},
     {'stdlib/3/concurrent/futures/process.pyi', 'third_party/2/concurrent/futures/process.pyi'},
     {'stdlib/3.7/dataclasses.pyi', 'third_party/3/dataclasses.pyi'},
+    {'stdlib/3/pathlib.pyi', 'third_party/2/pathlib2.pyi'},
 ]
 
 def main():

third_party/2/pathlib2.pyi

@@ -0,0 +1,120 @@
+from typing import Any, Generator, IO, Optional, Sequence, Tuple, Type, TypeVar, Union, List
+from types import TracebackType
+import os
+import sys
+
+_P = TypeVar('_P', bound='PurePath')
+
+if sys.version_info >= (3, 6):
+    _PurePathBase = os.PathLike[str]
+else:
+    _PurePathBase = object
+
+class PurePath(_PurePathBase):
+    parts = ...  # type: Tuple[str, ...]
+    drive = ...  # type: str
+    root = ...  # type: str
+    anchor = ...  # type: str
+    name = ...  # type: str
+    suffix = ...  # type: str
+    suffixes = ...  # type: List[str]
+    stem = ...  # type: str
+    if sys.version_info < (3, 5):
+        def __init__(self, *pathsegments: str) -> None: ...
+    elif sys.version_info < (3, 6):
+        def __new__(cls: Type[_P], *args: Union[str, PurePath]) -> _P: ...
+    else:
+        def __new__(cls: Type[_P], *args: Union[str, os.PathLike[str]]) -> _P: ...
+    def __hash__(self) -> int: ...
+    def __lt__(self, other: PurePath) -> bool: ...
+    def __le__(self, other: PurePath) -> bool: ...
+    def __gt__(self, other: PurePath) -> bool: ...
+    def __ge__(self, other: PurePath) -> bool: ...
+    def __truediv__(self: _P, key: Union[str, PurePath]) -> _P: ...
+    def __bytes__(self) -> bytes: ...
+    def as_posix(self) -> str: ...
+    def as_uri(self) -> str: ...
+    def is_absolute(self) -> bool: ...
+    def is_reserved(self) -> bool: ...
+    def match(self, path_pattern: str) -> bool: ...
+    def relative_to(self: _P, *other: Union[str, PurePath]) -> _P: ...
+    def with_name(self: _P, name: str) -> _P: ...
+    def with_suffix(self: _P, suffix: str) -> _P: ...
+    def joinpath(self: _P, *other: Union[str, PurePath]) -> _P: ...
+
+    @property
+    def parents(self: _P) -> Sequence[_P]: ...
+    @property
+    def parent(self: _P) -> _P: ...
+
+class PurePosixPath(PurePath): ...
+class PureWindowsPath(PurePath): ...
+
+class Path(PurePath):
+    def __enter__(self) -> Path: ...
+    def __exit__(self, exc_type: Optional[Type[BaseException]],
+                 exc_value: Optional[BaseException],
+                 traceback: Optional[TracebackType]) -> Optional[bool]: ...
+    @classmethod
+    def cwd(cls: Type[_P]) -> _P: ...
+    def stat(self) -> os.stat_result: ...
+    def chmod(self, mode: int) -> None: ...
+    def exists(self) -> bool: ...
+    def glob(self, pattern: str) -> Generator[Path, None, None]: ...
+    def group(self) -> str: ...
+    def is_dir(self) -> bool: ...
+    def is_file(self) -> bool: ...
+    def is_symlink(self) -> bool: ...
+    def is_socket(self) -> bool: ...
+    def is_fifo(self) -> bool: ...
+    def is_block_device(self) -> bool: ...
+    def is_char_device(self) -> bool: ...
+    def iterdir(self) -> Generator[Path, None, None]: ...
+    def lchmod(self, mode: int) -> None: ...
+    def lstat(self) -> os.stat_result: ...
+    if sys.version_info < (3, 5):
+        def mkdir(self, mode: int = ...,
+                  parents: bool = ...) -> None: ...
+    else:
+        def mkdir(self, mode: int = ..., parents: bool = ...,
+                  exist_ok: bool = ...) -> None: ...
+    def open(self, mode: str = ..., buffering: int = ...,
+             encoding: Optional[str] = ..., errors: Optional[str] = ...,
+             newline: Optional[str] = ...) -> IO[Any]: ...
+    def owner(self) -> str: ...
+    def rename(self, target: Union[str, PurePath]) -> None: ...
+    def replace(self, target: Union[str, PurePath]) -> None: ...
+    if sys.version_info < (3, 6):
+        def resolve(self: _P) -> _P: ...
+    else:
+        def resolve(self: _P, strict: bool = ...) -> _P: ...
+    def rglob(self, pattern: str) -> Generator[Path, None, None]: ...
+    def rmdir(self) -> None: ...
+    def symlink_to(self, target: Union[str, Path],
+                   target_is_directory: bool = ...) -> None: ...
+    def touch(self, mode: int = ..., exist_ok: bool = ...) -> None: ...
+    def unlink(self) -> None: ...
+
+    if sys.version_info >= (3, 5):
+        @classmethod
+        def home(cls: Type[_P]) -> _P: ...
+        if sys.version_info < (3, 6):
+            def __new__(cls: Type[_P], *args: Union[str, PurePath],
+                        **kwargs: Any) -> _P: ...
+        else:
+            def __new__(cls: Type[_P], *args: Union[str, os.PathLike[str]],
+                        **kwargs: Any) -> _P: ...
+
+        def absolute(self: _P) -> _P: ...
+        def expanduser(self: _P) -> _P: ...
+        def read_bytes(self) -> bytes: ...
+        def read_text(self, encoding: Optional[str] = ...,
+                      errors: Optional[str] = ...) -> str: ...
+        def samefile(self, other_path: Union[str, bytes, int, Path]) -> bool: ...
+        def write_bytes(self, data: bytes) -> int: ...
+        def write_text(self, data: str, encoding: Optional[str] = ...,
+                       errors: Optional[str] = ...) -> int: ...
+
+
+class PosixPath(Path, PurePosixPath): ...
+class WindowsPath(Path, PureWindowsPath): ...