Fix a few TODOs (#1487)

* fix some easy TODOs

* fix io

stdlib/2and3/mmap.pyi

@@ -1,21 +1,6 @@
-# Stubs for mmap
-
 import sys
-from types import TracebackType
-from typing import (Optional, Sequence, Union, Generic, TypeVar, overload,
-                    Iterable, Iterator, Sized, Type)
-
-
-_T = TypeVar('_T', str, bytes)
-
-# TODO already in PEP, have to get added to mypy
-_C = TypeVar('_C')
-class _ContextManager(Generic[_C]):
-    def __enter__(self) -> _C: ...
-    def __exit__(self, exc_type: Optional[Type[BaseException]],
-                 exc_val: Optional[Exception],
-                 exc_tb: Optional[TracebackType]) -> bool: ...
-
+from typing import (Optional, Sequence, Union, Generic, overload,
+                    Iterable, Iterator, Sized, ContextManager, AnyStr)
 
 ACCESS_READ = ...  # type: int
 ACCESS_WRITE = ...  # type: int
@@ -31,7 +16,7 @@ if sys.platform != 'win32':
 
     PAGESIZE = ...  # type: int
 
-class _mmap(Generic[_T]):
+class _mmap(Generic[AnyStr]):
     if sys.platform == 'win32':
         def __init__(self, fileno: int, length: int,
                      tagname: Optional[str] = ..., access: int = ...,
@@ -42,23 +27,23 @@ class _mmap(Generic[_T]):
                      prot: int = ..., access: int = ...,
                      offset: int = ...) -> None: ...
     def close(self) -> None: ...
-    def find(self, sub: _T,
+    def find(self, sub: AnyStr,
              start: int = ..., end: int = ...) -> int: ...
     def flush(self, offset: int = ..., size: int = ...) -> int: ...
     def move(self, dest: int, src: int, count: int) -> None: ...
-    def read(self, n: int = ...) -> _T: ...
-    def read_byte(self) -> _T: ...
-    def readline(self) -> _T: ...
+    def read(self, n: int = ...) -> AnyStr: ...
+    def read_byte(self) -> AnyStr: ...
+    def readline(self) -> AnyStr: ...
     def resize(self, newsize: int) -> None: ...
     def seek(self, pos: int, whence: int = ...) -> None: ...
     def size(self) -> int: ...
     def tell(self) -> int: ...
-    def write(self, bytes: _T) -> None: ...
-    def write_byte(self, byte: _T) -> None: ...
+    def write(self, bytes: AnyStr) -> None: ...
+    def write_byte(self, byte: AnyStr) -> None: ...
     def __len__(self) -> int: ...
 
 if sys.version_info >= (3,):
-    class mmap(_mmap, _ContextManager[mmap], Iterable[bytes], Sized):
+    class mmap(_mmap, ContextManager[mmap], Iterable[bytes], Sized):
         closed = ...  # type: bool
         def rfind(self, sub: bytes, start: int = ..., stop: int = ...) -> int: ...
         @overload

stdlib/3/io.pyi

@@ -16,19 +16,13 @@ SEEK_END = ...  # type: int
 
 open = builtins.open
 
-# FIXME when mypy handle condtional, we can uncomment the next block and remove
-# the temporary fix
-# if sys.version_info >= (3, 3):
-#     BlockingIOError = BlockingIOError
-#     class UnsupportedOperation(OSError, ValueError): ...
-# else:
-#     class BlockingIOError(IOError):
-#         characters_written = ...  # type: int
-#     class UnsupportedOperation(IOError, ValueError): ...
-class BlockingIOError(OSError):
-    characters_written = ...  # type: int
-class UnsupportedOperation(OSError, ValueError): ...
-
+if sys.version_info >= (3, 3):
+    BlockingIOError = builtins.BlockingIOError
+    class UnsupportedOperation(OSError, ValueError): ...
+else:
+    class BlockingIOError(IOError):
+        characters_written: int
+    class UnsupportedOperation(IOError, ValueError): ...
 
 class IOBase:
     def __iter__(self) -> Iterator[bytes]: ...

stdlib/3/typing.pyi

@@ -116,9 +116,8 @@ class Generator(Iterator[_T_co], Generic[_T_co, _T_contra, _V_co]):
     def send(self, value: _T_contra) -> _T_co: ...
 
     @abstractmethod
-    def throw(self, typ: Type[BaseException], val: Optional[BaseException] = None,
-              # TODO: tb should be TracebackType but that's defined in types
-              tb: Any = None) -> None: ...
+    def throw(self, typ: Type[BaseException], val: Optional[BaseException] = ...,
+              tb: Optional[TracebackType] = ...) -> None: ...
 
     @abstractmethod
     def close(self) -> None: ...
@@ -144,9 +143,8 @@ class Coroutine(Awaitable[_V_co], Generic[_T_co, _T_contra, _V_co]):
     def send(self, value: _T_contra) -> _T_co: ...
 
     @abstractmethod
-    def throw(self, typ: Type[BaseException], val: Optional[BaseException] = None,
-              # TODO: tb should be TracebackType but that's defined in types
-              tb: Any = None) -> None: ...
+    def throw(self, typ: Type[BaseException], val: Optional[BaseException] = ...,
+              tb: Optional[TracebackType] = ...) -> None: ...
 
     @abstractmethod
     def close(self) -> None: ...
@@ -399,8 +397,7 @@ class IO(Iterator[AnyStr], Generic[AnyStr]):
     def __enter__(self) -> 'IO[AnyStr]': ...
     @abstractmethod
     def __exit__(self, t: Optional[Type[BaseException]], value: Optional[BaseException],
-                 # TODO: traceback should be TracebackType but that's defined in types
-                 traceback: Optional[Any]) -> bool: ...
+                 traceback: Optional[TracebackType]) -> bool: ...
 
 class BinaryIO(IO[bytes]):
     # TODO readinto

stdlib/3/unittest/__init__.pyi

@@ -16,10 +16,9 @@ _E = TypeVar('_E', bound=Exception)
 
 
 def expectedFailure(func: _FT) -> _FT: ...
-# TODO: Once python/mypy#1551 is fixed, the following need _FT instead of Any
-def skip(reason: str) -> Callable[[Any], Any]: ...
-def skipIf(condition: object, reason: str) -> Callable[[Any], Any]: ...
-def skipUnless(condition: object, reason: str) -> Callable[[Any], Any]: ...
+def skip(reason: str) -> Callable[[_FT], _FT]: ...
+def skipIf(condition: object, reason: str) -> Callable[[_FT], _FT]: ...
+def skipUnless(condition: object, reason: str) -> Callable[[_FT], _FT]: ...
 
 class SkipTest(Exception):
     def __init__(self, reason: str) -> None: ...