Make BytesIO inherit from BufferedIOBase.

stdlib/3/gzip.pyi

@@ -40,7 +40,7 @@ class GzipFile(_compression.BaseStream):
     def writable(self) -> bool: ...
     def seekable(self) -> bool: ...
     def seek(self, offset: int, whence: int = ...) -> int: ...
-    def readline(self, size: int = ...) -> bytes: ...
+    def readline(self, size: Optional[int] = ...) -> bytes: ...
 
 class _GzipReader(_compression.DecompressReader):
     def __init__(self, fp: IO[bytes]) -> None: ...

stdlib/3/io.pyi

@@ -44,7 +44,7 @@ class IOBase:
     def truncate(self, __size: Optional[int] = ...) -> int: ...
     def writable(self) -> bool: ...
     def writelines(self, __lines: Iterable[Union[bytes, bytearray]]) -> None: ...
-    def readline(self, __size: int = ...) -> bytes: ...
+    def readline(self, __size: Optional[int] = ...) -> bytes: ...
     def __del__(self) -> None: ...
     @property
     def closed(self) -> bool: ...
@@ -65,7 +65,6 @@ class BufferedIOBase(IOBase):
     def read(self, __size: Optional[int] = ...) -> bytes: ...
     def read1(self, __size: int = ...) -> bytes: ...
 
-
 class FileIO(RawIOBase):
     mode: str
     name: Union[int, str]
@@ -77,52 +76,27 @@ class FileIO(RawIOBase):
         opener: Optional[Callable[[Union[int, str], str], int]] = ...
     ) -> None: ...
 
-# TODO should extend from BufferedIOBase
-class BytesIO(BinaryIO):
+class BytesIO(BufferedIOBase, BinaryIO):
     def __init__(self, initial_bytes: bytes = ...) -> None: ...
     # BytesIO does not contain a "name" field. This workaround is necessary
     # to allow BytesIO sub-classes to add this field, as it is defined
     # as a read-only property on IO[].
     name: Any
+    def __enter__(self: _T) -> _T: ...
     def getvalue(self) -> bytes: ...
     def getbuffer(self) -> memoryview: ...
-    # copied from IOBase
-    def __iter__(self) -> Iterator[bytes]: ...
-    def __next__(self) -> bytes: ...
-    def __enter__(self) -> BytesIO: ...
-    def __exit__(self, t: Optional[Type[BaseException]] = ..., value: Optional[BaseException] = ...,
-                 traceback: Optional[TracebackType] = ...) -> Optional[bool]: ...
-    def close(self) -> None: ...
-    def fileno(self) -> int: ...
-    def flush(self) -> None: ...
-    def isatty(self) -> bool: ...
-    def readable(self) -> bool: ...
-    def readlines(self, __size: int = ...) -> List[bytes]: ...
-    def seek(self, __pos: int, __whence: int = ...) -> int: ...
-    def seekable(self) -> bool: ...
-    def tell(self) -> int: ...
-    def truncate(self, __size: Optional[int] = ...) -> int: ...
-    def writable(self) -> bool: ...
-    # TODO should be the next line instead
-    # def writelines(self, lines: List[Union[bytes, bytearray]]) -> None: ...
-    def writelines(self, __lines: Any) -> None: ...
-    def readline(self, __size: Optional[int] = ...) -> bytes: ...
-    def __del__(self) -> None: ...
-    closed: bool
-    # copied from BufferedIOBase
-    def detach(self) -> RawIOBase: ...
-    def readinto(self, __buffer: _bytearray_like) -> int: ...
-    def write(self, __b: Union[bytes, bytearray]) -> int: ...
-    def readinto1(self, __buffer: _bytearray_like) -> int: ...
-    def read(self, __size: Optional[int] = ...) -> bytes: ...
     if sys.version_info >= (3, 7):
         def read1(self, __size: Optional[int] = ...) -> bytes: ...
     else:
-        def read1(self, __size: Optional[int]) -> bytes: ...
+        def read1(self, __size: Optional[int]) -> bytes: ...  # type: ignore
 
 class BufferedReader(BufferedIOBase):
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
     def peek(self, __size: int = ...) -> bytes: ...
+    if sys.version_info >= (3, 7):
+        def read1(self, __size: int = ...) -> bytes: ...
+    else:
+        def read1(self, __size: int) -> bytes: ...  # type: ignore
 
 class BufferedWriter(BufferedIOBase):
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
@@ -133,6 +107,10 @@ class BufferedRandom(BufferedReader, BufferedWriter):
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
     def seek(self, __target: int, __whence: int = ...) -> int: ...
     def tell(self) -> int: ...
+    if sys.version_info >= (3, 7):
+        def read1(self, __size: int = ...) -> bytes: ...
+    else:
+        def read1(self, __size: int) -> bytes: ...  # type: ignore
 
 class BufferedRWPair(BufferedIOBase):
     def __init__(self, reader: RawIOBase, writer: RawIOBase,

stdlib/3/lzma.pyi

@@ -85,7 +85,7 @@ class LZMAFile(io.BufferedIOBase, IO[bytes]):  # type: ignore  # python/mypy#502
     def peek(self, size: int = ...) -> bytes: ...
     def read(self, size: Optional[int] = ...) -> bytes: ...
     def read1(self, size: int = ...) -> bytes: ...
-    def readline(self, size: int = ...) -> bytes: ...
+    def readline(self, size: Optional[int] = ...) -> bytes: ...
     def write(self, data: bytes) -> int: ...
     def seek(self, offset: int, whence: int = ...) -> int: ...
     def tell(self) -> int: ...

tests/stubtest_whitelists/py35.txt

@@ -32,8 +32,6 @@ gettext.npgettext
 gettext.pgettext
 importlib.metadata
 importlib.resources
-io.BufferedRandom.read1
-io.BufferedReader.read1
 io.StringIO.readline
 ipaddress._BaseNetwork.__init__
 json.dump

tests/stubtest_whitelists/py36.txt

@@ -29,8 +29,6 @@ gettext.npgettext
 gettext.pgettext
 importlib.metadata
 importlib.resources
-io.BufferedRandom.read1
-io.BufferedReader.read1
 io.StringIO.readline
 ipaddress._BaseNetwork.__init__
 json.loads

tests/stubtest_whitelists/py3_common.txt

@@ -247,6 +247,7 @@ io.BufferedReader.truncate
 io.BufferedWriter.seek
 io.BufferedWriter.truncate
 io.BytesIO.readlines
+io.BytesIO.seek  # Parameter name for a positional-only param differs from its name in the inherited method
 io.FileIO.seek
 io.StringIO.seek
 io.StringIO.truncate