asyncio: expose WriteTransport.get_write_buffer_limits on all Python versions (#7718)

stdlib/asyncio/transports.pyi

@@ -28,9 +28,7 @@ class ReadTransport(BaseTransport):
 class WriteTransport(BaseTransport):
     def set_write_buffer_limits(self, high: int | None = ..., low: int | None = ...) -> None: ...
     def get_write_buffer_size(self) -> int: ...
-    if sys.version_info >= (3, 9):
-        def get_write_buffer_limits(self) -> tuple[int, int]: ...
-
+    def get_write_buffer_limits(self) -> tuple[int, int]: ...
     def write(self, data: Any) -> None: ...
     def writelines(self, list_of_data: list[Any]) -> None: ...
     def write_eof(self) -> None: ...

tests/stubtest_allowlists/py36.txt

@@ -8,6 +8,8 @@ asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures._TracebackLogger.__init__
 asyncio.locks._ContextManagerMixin.__enter__  # Always raises; deliberately omitted from the stub
 asyncio.locks._ContextManagerMixin.__exit__  # Always raises; deliberately omitted from the stub
+asyncio.transports.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
+asyncio.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
 builtins.float.__setformat__  # Internal method for CPython test suite
 builtins.str.maketrans
 cmath.log

tests/stubtest_allowlists/py37.txt

@@ -11,6 +11,8 @@ asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future._callbacks  # Usually initialized from c object
 asyncio.locks._ContextManagerMixin.__enter__  # Always raises; deliberately omitted from the stub
 asyncio.locks._ContextManagerMixin.__exit__  # Always raises; deliberately omitted from the stub
+asyncio.transports.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
+asyncio.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
 builtins.dict.get
 builtins.float.__set_format__  # Internal method for CPython test suite
 builtins.str.maketrans

tests/stubtest_allowlists/py38.txt

@@ -17,6 +17,8 @@ asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future._callbacks  # Usually initialized from c object
 asyncio.locks._ContextManagerMixin.__enter__  # Always raises; deliberately omitted from the stub
 asyncio.locks._ContextManagerMixin.__exit__  # Always raises; deliberately omitted from the stub
+asyncio.transports.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
+asyncio.WriteTransport.get_write_buffer_limits  # Documented. Exists in subclasses, but not in WriteTransport itself
 builtins.dict.get
 builtins.float.__set_format__  # Internal method for CPython test suite
 collections.AsyncGenerator.asend  # async at runtime, deliberately not in the stub, see #7491. Pos-only differences also.