PyQt6: QEvent.type() returns int instead of QEvent.Type

[Phil Thompson]

On 28/04/2022 20:16, Florian Bruhin wrote:
> On Thu, Apr 28, 2022 at 09:42:46AM +0100, Phil Thompson wrote:
>> So if we can solve the pickle problem I think I'd be Ok to take this
>> approach.
> 
> I think the most elegant way to do this is via the _missing_ 
> classmethod
> on enums. This is public API:
> https://docs.python.org/3/library/enum.html#supported-sunder-names
> 
> The drawback about the approach is that it's possible to do
> SomePyQtEnum(1337) and that happily returns a value, so at this point,
> the cpp2py() can probably just be implemented in _missing_ altogether.
> 
> See the attached file. The _missing_ method needs to use cpp2py so that
> even values which haven't been passed through cpp2py before work fine.
> 
> This means I had to rewrite cpp2py slightly to avoid triggering
> _missing_. The __members__ attribute is documented too:
> https://docs.python.org/3/library/enum.html#iteration
> 
> Alternatively, "if cpp in list(etype):" could be used, but that builds
> up an unnecessary list ("cpp in etype" will not work, raising a
> TypeError).
> 
> If we didn't want to use missing (so that SomePyQtEnum(1337) does not
> work), I suppose it can be solved by defining __reduce_ex__ on the enum
> type somehow, but I tried, and it never was called (only enum.py's 
> was).

I had come to the same conclusion that the only way to support pickle 
was to use a sub-class of Enum and re-implement _missing_. I had hoped 
to be able to use a regular Enum (and IntEnum).

Phil