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

[John Snow]

On 4/1/20 8:40 AM, Max Reitz wrote:
> On 31.03.20 19:39, Kevin Wolf wrote:
>> Am 31.03.2020 um 19:23 hat John Snow geschrieben:
>>>
>>>
>>> On 3/31/20 6:21 AM, Max Reitz wrote:
>>>> 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?
>>>>
>>>
>>> One of --strict's implied options, I'm not sure which. Otherwise, mypy
>>> is geared towards a 'gradual typing' discipline.
>>>
>>> In truth, I'm a little thankful for that because it helps avoid yak
>>> shaving marathons.
> 
> Sure.  I was just looking into the different options.  I was interested
> in whether I could come up with a mode that leaves wholly untyped code
> alone, but warns for code that mixes it.  Or something.
> 
>>> It does mean that sometimes the annotations don't "do anything" yet,
>>> apart from offering hints and documentation in e.g. pycharm. Which does
>>> mean that sometimes they can be completely wrong...
>>>
>>> The more we add, the more we'll catch problems.
>>>
>>> Once this series is dusted I'll try to tackle more conversions for
>>> iotests, qmp, etc. I've got a few WIP patches to tackle conversions for
>>> tests/qemu-iotests/*.py but I am trying to shepherd this one in first
>>> before I go bananas.
> 
> Sure, sure.
> 
>>>> (--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...?)
>>>>
>>>
>>> "disallow-any-generics" means disallowing `Any` generics, not
>>> disallowing generics ... in general. (I think? I've been using mypy in
>>> strict mode for a personal project a lot lately and I use generics in a
>>> few places, it seems OK.)
>>
>> --disallow-any-generics
>>       disallow usage of generic types that do not specify explicit type 
>> parameters
>>
>> So it will complain if you say just List, and you need to be explicit if
>> you really want List[Any]. Which I think is a reasonable thing to
>> require.
> 
> OK.  So it’s “disallow ‘any’ generics”, not “disallow any ‘generic’s”.
> Not easy to parse.  (Yes, yes, I should’ve actually read the man page...)
> 
> Good to know that mypy and me actually do seem to loosely agree on what
> a generic is. :)
> 
> Max
> 

Are we squared up for this series? I am actually not sure.

--js