Constructor executed twice when overriding constructor in System.Object. #495

Activity

1. rickardraysearch commented on Jun 15, 2017

   

   rickardraysearch

   on Jun 15, 2017

   Last edited by rickardraysearch

   Contributor

   More actions

   Furthermore, if you add arguments to the constructor, the arguments are only passed the second time.

   class X(System.Object):
       __namespace__ = "PyTest"
   
       def __init__(self, *args):
           print("Running X constructor, args = {0}".format(args))
   
   x = X(1,2)

   produces the output

   Running X constructor, args = ()
   Running X constructor, args = (1, 2)
   

   It seems that the first invocation is from the call in Python.Runtime.MetaType.tp_call to tp_new, whereas the second invocation is from the call to py__init__ using Runtime.PyObject_Call.

   Is the error that somehow the call to tp_new also ends up calling __init__?
2. filmor commented on Jun 16, 2017

   

   filmor

   on Jun 16, 2017

   Member

   More actions

   Hmm, the comment says

       /// Metatype __call__ implementation. This is needed to ensure correct
       /// initialization (__init__ support), because the tp_call we inherit
       /// from PyType_Type won't call __init__ for metatypes it doesn't know.
   

   Maybe this changed in Python? I'll have a look.
3. filmor

   added 2 commits that reference this issue on Jun 16, 2017

   Drop tp_call implementation from metatype.

   ...

   350b65a

   Drop tp_call implementation from metatype.

   ...

   9f64f56
4. filmor

   added a commit that references this issue on Jun 26, 2017

   Another shot at #495 (#503)

   ...

   a5f5dc2
5. filmor commented on Jul 11, 2017

   

   filmor

   on Jul 11, 2017

   Member

   More actions

   Fixed by #503.
6. filmor

   closed this as completedon Jul 11, 2017
7. testrunner123

   added a commit that references this issue on Sep 22, 2017

   Another shot at pythonnet#495 (pythonnet#503)

   ...

   330fde3