[python-win32] win32com does not recognise an Interface for events

[Mark Hammond]

> OLE Viewer finds a second interface IS7ProSimEvents that is 
> made the default source makepy does not recognise 
> IS7ProSimEvents as an interface at all.

That seems strange - for events, even non-dual interfaces should be
supported.


> gencache.GetClassForCLSID(clsid) returns the class with 
> docstring """IS7ProSim Interface for S7ProSim COM Object"""
> This is correct.
> This class has no sources, as can be seen in the OLE Viewer 
> output, and the AttributError is thrown. OK.
> klass.coclass_clsid is '{83CC0D83-FEDA-11D1-BE76-0060B06816CF}'. OK.
> gencache.GetClassForCLSID(klass.coclass_clsid) returns a 
> class with the following properties:
>     base class          : CoClassBaseClass
>     coclass_interface : [<class
> win32com.gen_py.83CC0D80-FEDA-11D1-BE76-0060B06816CFx0x1x0.IS7
> ProSim at 
> 0x00E4DCF0>]
>     coclass_sources      : []
>     clsid              : {83CC0D83-FEDA-11D1-BE76-0060B06816CF}
> There is no attribute default_source, so the AttributeError 
> is thrown again.
> 
> This is correct with respect to the makepy output, but not 
> with repsect to the actual OLE object. 
> IMHO the makepy output should have included IS7PrSomEvents as 
> an interface and declared it as default_source within CoClass 
> S7SimPro. Right?

Yep - so presumably this is the same problem as above.

> So how come it does not?

No idea.

> Tracking the makepy actions:
> ----------------------------
> A convenient break point location is makepy.py line 263: 
> gen.generate(....) Walking on till genpy.py line 737 
> self.CollectOleItemInfosFromType()
> returned a (correct) list
> of all OleItem information headers:
>       infotype                             doc[0]             
>        doc[1]
>       TKIND_INTERFACE,    'IS7ProSimEvents', 'Event interface for 
> S7ProSim COM Object'
>       TKIND_COCLASS,         'S7ProSim',             'S7ProSim Class'
>       TKIND_DISPATCH,       'IS7ProSim',           'IS7ProSim 
> Interface 
> for S7ProSim COM Object'
>       a number of (infotype 0 and 6) entries for the constant 
> enumerations This list is run through to colelct and build 
> all oleItems, enumItems, recordItems and vtableItems
>      pass 0: TKIND_INTERFACE,     'IS7ProSimEvents', 'Event interface 
> for S7ProSim COM Object'
>            oleItem, vtableItem = 
> self._Build_Interface(type_info_tuple)
> returns (None, <VTableItem>)
>               returns (None, <VTableItem>). This will lead to 
> the exclusion of this interface later on.
> 
> So how does this happen?

It would appear that makepy is excluding non-dual interfaces, and that the
integration with the 'universal' support for vtable interfaces isn't
complete.

> Did I stumble on a bug here or am I completely missing a 
> point? Please help out.

I think you struck a bug - we should be able to support incoming interfaces
(ie, events) using only vtables.

Mark