Consistently use '= ...' for optional parameters.

stdlib/3/os/__init__.pyi

@@ -157,7 +157,7 @@ class statvfs_result:  # Unix only
 def name() -> str: ...
 def fsencode(filename: str) -> bytes: ...
 def fsdecode(filename: bytes) -> str: ...
-def get_exec_path(env=None) -> List[str] : ...
+def get_exec_path(env=...) -> List[str] : ...
 # NOTE: get_exec_path(): returns List[bytes] when env not None
 def ctermid() -> str: ...  # Unix only
 def getegid() -> int: ...  # Unix only
@@ -173,8 +173,8 @@ def getppid() -> int: ...
 def getresuid() -> Tuple[int, int, int]: ...  # Unix only
 def getresgid() -> Tuple[int, int, int]: ...  # Unix only
 def getuid() -> int: ...  # Unix only
-def getenv(key: str, default: str = None) -> str: ...
-def getenvb(key: bytes, default: bytes = None) -> bytes: ...
+def getenv(key: str, default: str = ...) -> str: ...
+def getenvb(key: bytes, default: bytes = ...) -> bytes: ...
 # TODO mixed str/bytes putenv arguments
 def putenv(key: AnyStr, value: AnyStr) -> None: ...
 def setegid(egid: int) -> None: ...  # Unix only
@@ -195,8 +195,8 @@ def umask(mask: int) -> int: ...
 def uname() -> Tuple[str, str, str, str, str]: ...  # Unix only
 def unsetenv(key: AnyStr) -> None: ...
 # Return IO or TextIO
-def fdopen(fd: int, mode: str = 'r', encoding: str = None, errors: str = None,
-           newline: str = None, closefd: bool = True) -> Any: ...
+def fdopen(fd: int, mode: str = ..., encoding: str = ..., errors: str = ...,
+           newline: str = ..., closefd: bool = ...) -> Any: ...
 def close(fd: int) -> None: ...
 def closerange(fd_low: int, fd_high: int) -> None: ...
 def device_encoding(fd: int) -> Optional[str]: ...
@@ -212,7 +212,7 @@ def fsync(fd: int) -> None: ...
 def ftruncate(fd: int, length: int) -> None: ...  # Unix only
 def isatty(fd: int) -> bool: ...  # Unix only
 def lseek(fd: int, pos: int, how: int) -> int: ...
-def open(file: AnyStr, flags: int, mode: int = 0o777) -> int: ...
+def open(file: AnyStr, flags: int, mode: int = ...) -> int: ...
 def openpty() -> Tuple[int, int]: ...  # some flavors of Unix
 def pipe() -> Tuple[int, int]: ...
 def read(fd: int, n: int) -> bytes: ...
@@ -235,19 +235,19 @@ def lchown(path: str, uid: int, gid: int) -> None: ...  # Unix only
 def link(src: AnyStr, link_name: AnyStr) -> None: ...
 
 @overload
-def listdir(path: str = '.') -> List[str]: ...
+def listdir(path: str = ...) -> List[str]: ...
 @overload
 def listdir(path: bytes) -> List[bytes]: ...
 
 def lstat(path: AnyStr) -> stat_result: ...
-def mkfifo(path, mode: int=0o666) -> None: ...  # Unix only
-def mknod(filename: AnyStr, mode: int = 0o600, device: int = 0) -> None: ...
+def mkfifo(path, mode: int=...) -> None: ...  # Unix only
+def mknod(filename: AnyStr, mode: int = ..., device: int = ...) -> None: ...
 def major(device: int) -> int: ...
 def minor(device: int) -> int: ...
 def makedev(major: int, minor: int) -> int: ...
-def mkdir(path: AnyStr, mode: int = 0o777) -> None: ...
-def makedirs(path: AnyStr, mode: int = 0o777,
-             exist_ok: bool = False) -> None: ...
+def mkdir(path: AnyStr, mode: int = ...) -> None: ...
+def makedirs(path: AnyStr, mode: int = ...,
+             exist_ok: bool = ...) -> None: ...
 def pathconf(path: str, name: str) -> int: ...  # Unix only
 def readlink(path: AnyStr) -> AnyStr: ...
 def remove(path: AnyStr) -> None: ...
@@ -256,17 +256,17 @@ def rename(src: AnyStr, dst: AnyStr) -> None: ...
 def renames(old: AnyStr, new: AnyStr) -> None: ...
 def rmdir(path: AnyStr) -> None: ...
 def stat(path: AnyStr) -> stat_result: ...
-def stat_float_times(newvalue: Union[bool, None] = None) -> bool: ...
+def stat_float_times(newvalue: Union[bool, None] = ...) -> bool: ...
 def statvfs(path: str) -> statvfs_result: ... # Unix only
 def symlink(source: AnyStr, link_name: AnyStr,
-            target_is_directory: bool = False) -> None:
+            target_is_directory: bool = ...) -> None:
     ...  # final argument in Windows only
 def unlink(path: AnyStr) -> None: ...
-def utime(path: AnyStr, times: Union[Tuple[int, int], Tuple[float, float]] = None) -> None: ...
+def utime(path: AnyStr, times: Union[Tuple[int, int], Tuple[float, float]] = ...) -> None: ...
 
 # TODO onerror: function from OSError to void
-def walk(top: AnyStr, topdown: bool = True, onerror: Any = None,
-         followlinks: bool = False) -> Iterator[Tuple[AnyStr, List[AnyStr],
+def walk(top: AnyStr, topdown: bool = ..., onerror: Any = ...,
+         followlinks: bool = ...) -> Iterator[Tuple[AnyStr, List[AnyStr],
                                                       List[AnyStr]]]: ...
 # walk(): "By default errors from the os.listdir() call are ignored.  If
 # optional arg 'onerror' is specified, it should be a function; it
@@ -298,8 +298,8 @@ def plock(op: int) -> None: ...  # Unix only ???op is int?
 from io import TextIOWrapper as _TextIOWrapper
 class popen(_TextIOWrapper):
     # TODO 'b' modes or bytes command not accepted?
-    def __init__(self, command: str, mode: str = 'r',
-                 bufsize: int = -1) -> None: ...
+    def __init__(self, command: str, mode: str = ...,
+                 bufsize: int = ...) -> None: ...
     def close(self) -> Any: ... # may return int
 
 def spawnl(mode: int, path: AnyStr, arg0: AnyStr, *args: AnyStr) -> int: ...
@@ -316,12 +316,12 @@ def spawnvp(mode: int, file: AnyStr, args: List[AnyStr]) -> int: ...  # Unix onl
 def spawnvpe(mode: int, file: AnyStr, args: List[AnyStr],
              env: Mapping[str, str]) -> int:
     ...  # Unix only
-def startfile(path: str, operation: Union[str, None] = None) -> None: ...  # Windows only
+def startfile(path: str, operation: Union[str, None] = ...) -> None: ...  # Windows only
 def system(command: AnyStr) -> int: ...
 def times() -> Tuple[float, float, float, float, float]: ...
 def wait() -> Tuple[int, int]: ...  # Unix only
 def waitpid(pid: int, options: int) -> Tuple[int, int]: ...
-def wait3(options: Union[int, None] = None) -> Tuple[int, int, Any]: ...  # Unix only
+def wait3(options: Union[int, None] = ...) -> Tuple[int, int, Any]: ...  # Unix only
 def wait4(pid: int, options: int) -> Tuple[int, int, Any]:
     ...  # Unix only
 def WCOREDUMP(status: int) -> bool: ...  # Unix only

stdlib/3/os/path.pyi

@@ -47,7 +47,7 @@ def join(path: AnyStr, *paths: AnyStr) -> AnyStr: ...
 def normcase(path: AnyStr) -> AnyStr: ...
 def normpath(path: AnyStr) -> AnyStr: ...
 def realpath(path: AnyStr) -> AnyStr: ...
-def relpath(path: AnyStr, start: AnyStr = None) -> AnyStr: ...
+def relpath(path: AnyStr, start: AnyStr = ...) -> AnyStr: ...
 
 def samefile(path1: AnyStr, path2: AnyStr) -> bool: ...
 def sameopenfile(fp1: int, fp2: int) -> bool: ...