Re: [PATCH v10 10/14] iotests: add hmp helper with logging

[Max Reitz]

On 01.04.20 14:28, Max Reitz wrote:
> On 31.03.20 16:00, Kevin Wolf wrote:
>> Am 31.03.2020 um 12:21 hat Max Reitz geschrieben:
>>> On 31.03.20 02:00, John Snow wrote:
>>>> Minor cleanup for HMP functions; helps with line length and consolidates
>>>> HMP helpers through one implementation function.
>>>>
>>>> Although we are adding a universal toggle to turn QMP logging on or off,
>>>> many existing callers to hmp functions don't expect that output to be
>>>> logged, which causes quite a few changes in the test output.
>>>>
>>>> For now, offer a use_log parameter.
>>>>
>>>>
>>>> Typing notes:
>>>>
>>>> QMPResponse is just an alias for Dict[str, Any]. It holds no special
>>>> meanings and it is not a formal subtype of Dict[str, Any]. It is best
>>>> thought of as a lexical synonym.
>>>>
>>>> We may well wish to add stricter subtypes in the future for certain
>>>> shapes of data that are not formalized as Python objects, at which point
>>>> we can simply retire the alias and allow mypy to more strictly check
>>>> usages of the name.
>>>>
>>>> Signed-off-by: John Snow <address@hidden>
>>>> ---
>>>>  tests/qemu-iotests/iotests.py | 35 ++++++++++++++++++++++-------------
>>>>  1 file changed, 22 insertions(+), 13 deletions(-)
>>>
>>> Reviewed-by: Max Reitz <address@hidden>
>>>
>>>> diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
>>>> index b08bcb87e1..dfc753c319 100644
>>>> --- a/tests/qemu-iotests/iotests.py
>>>> +++ b/tests/qemu-iotests/iotests.py
>>>> @@ -37,6 +37,10 @@
>>>>  
>>>>  assert sys.version_info >= (3, 6)
>>>>  
>>>> +# Type Aliases
>>>> +QMPResponse = Dict[str, Any]
>>>> +
>>>> +
>>>>  faulthandler.enable()
>>>>  
>>>>  # This will not work if arguments contain spaces but is necessary if we
>>>> @@ -540,25 +544,30 @@ def add_incoming(self, addr):
>>>>          self._args.append(addr)
>>>>          return self
>>>>  
>>>> -    def pause_drive(self, drive, event=None):
>>>> -        '''Pause drive r/w operations'''
>>>> +    def hmp(self, command_line: str, use_log: bool = False) -> 
>>>> QMPResponse:
>>>> +        cmd = 'human-monitor-command'
>>>> +        kwargs = {'command-line': command_line}
>>>> +        if use_log:
>>>> +            return self.qmp_log(cmd, **kwargs)
>>>> +        else:
>>>> +            return self.qmp(cmd, **kwargs)
>>>
>>> Hm.  I suppose I should take this chance to understand something about
>>> mypy.  QEMUMachine.qmp() isn’t typed, so mypy can’t check that this
>>> really returns QMPResponse.  Is there some flag to make it?  Like
>>> --actually-check-types?
>>
>> There is --check-untyped-defs, but I'm not sure if that actually changes
>> the return type of untyped functions from Any to an inferred type. I
>> kind of doubt it.
> 
> Well, but Any doesn’t fit into QMPResponse, so there should be an error
> reported somewhere.
> 
>>> (--strict seems, well, overly strict?  Like not allowing generics, I
>>> don’t see why.  Or I suppose for the time being we want to allow untyped
>>> definitions, as long as they don’t break type assertions such as it kind
>>> of does here...?)
>>
>> At least, --strict does actually complain about this one because Any
>> isn't good enough any more (it includes --warn-return-any):
> 
> Hm, yes, but we’re not at a point where it’s really feasible to enable
> --strict...
> 
>> iotests.py:560: warning: Returning Any from function declared to return 
>> "Dict[str, Any]"
>> iotests.py:560: error: Call to untyped function "qmp_log" in typed context
>> iotests.py:562: warning: Returning Any from function declared to return 
>> "Dict[str, Any]"
>>
>> Not sure why you think it doesn't allow generics? I never had problems
>> with that, even in my Python museum. :-)
> 
> I thought --disallow-any-generics would mean that.  But I suppose mypy
> understands a “generic” to be something else than I do, as John
> described... *shrug*

Oh.  John didn’t describe that.  I just read the “Any” thing wrong,
again.  (On my first read, I thought he just used the back ticks to
stress the word “any”, not to refer to the type “Any”.)

Max

signature.asc
Description: OpenPGP digital signature