On 5/14/20 7:53 AM, John Snow wrote:
> mypy considers it incorrect to use `bool` to statically return false,
> because it will assume that it could conceivably return True, and gives
> different analysis in that case. Use a None return to achieve the same
> effect, but make mypy happy.
>
> Note: Pylint considers function signatures as code that might trip the
> duplicate-code checker. I'd rather not disable this as it does not
> trigger often in practice, so I'm disabling it as a one-off and filed a
> change request; see https://github.com/PyCQA/pylint/issues/3619
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> python/qemu/lib/machine.py | 8 ++++++--
> python/qemu/lib/qmp.py | 10 ++++++++--
> 2 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/python/qemu/lib/machine.py b/python/qemu/lib/machine.py
> index b2f0412197..2f94c851ed 100644
> --- a/python/qemu/lib/machine.py
> +++ b/python/qemu/lib/machine.py
> @@ -24,6 +24,8 @@
> import shutil
> import socket
> import tempfile
> +from typing import Optional, Type
> +from types import TracebackType
>
> from . import qmp
>
> @@ -127,9 +129,11 @@ def __init__(self, binary, args=None, wrapper=None, name=None,
> def __enter__(self):
> return self
>
> - def __exit__(self, exc_type, exc_val, exc_tb):
> + def __exit__(self,
> + exc_type: Optional[Type[BaseException]],
> + exc_val: Optional[BaseException],
> + exc_tb: Optional[TracebackType]) -> None:
> self.shutdown()
> - return False
>
> def add_monitor_null(self):
> """
> diff --git a/python/qemu/lib/qmp.py b/python/qemu/lib/qmp.py
> index 73d49050ed..b91c9d5c1c 100644
> --- a/python/qemu/lib/qmp.py
> +++ b/python/qemu/lib/qmp.py
> @@ -14,7 +14,9 @@
> from typing import (
> Optional,
> TextIO,
> + Type,
> )
> +from types import TracebackType
>
>
> class QMPError(Exception):
> @@ -146,10 +148,14 @@ def __enter__(self):
> # Implement context manager enter function.
> return self
>
> - def __exit__(self, exc_type, exc_value, exc_traceback):
> + def __exit__(self,
> + # pylint: disable=duplicate-code
> + # see https://github.com/PyCQA/pylint/issues/3619
> + exc_type: Optional[Type[BaseException]],
> + exc_val: Optional[BaseException],
> + exc_tb: Optional[TracebackType]) -> None:
> # Implement context manager exit function.
> self.close()
> - return False
>
> def connect(self, negotiate=True):
> """
>
Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>