I was trying to invoke a C# function with an argument of type Nullable. Python.NET reported that it could find no function matching the arguments. Eventually, I tried to test the fix for issue #460.
Python 3.8.7 (tags/v3.8.7:6503f05, Dec 21 2020, 17:59:51) [MSC v.1928 64 bit (AMD64)]
Type 'copyright', 'credits' or 'license' for more information
IPython 7.28.0 -- An enhanced Interactive Python. Type '?' for help.
[ins] In [1]: import clr
[ins] In [2]: from System import (UInt32, Nullable)
[ins] In [3]: Nullable[UInt32](3)
Out[3]: <System.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]] object at 0x0000020A6AF106D0>
[ins] In [4]: Nullable[UInt32](None)
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-4-b1659b301f87> in <module>
----> 1 Nullable[UInt32](None)
TypeError: No constructor matches given arguments: (<class 'NoneType'>)
I also tried testing against pythonnet 3.0.0.a2. I see the following stack trace.
Python 3.8.7 (tags/v3.8.7:6503f05, Dec 21 2020, 17:59:51) [MSC v.1928 64 bit (AMD64)]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.0.1 -- An enhanced Interactive Python. Type '?' for help.
[ins] In [1]: import clr
[ins] In [2]: from System import DateTime, Double, Guid, Nullable, String, UInt32
[ins] In [3]: Nullable[Double](None)
Python.Runtime.PythonException: 'NoneType' value cannot be converted to System.Double
The above exception was the direct cause of the following exception:
System.ArgumentException: 'NoneType' value cannot be converted to System.Double in method Void .ctor(Double) ---> Python.Runtime.PythonException:
'NoneType' value cannot be converted to System.Double
--- End of inner exception stack trace ---
The above exception was the direct cause of the following exception:
System.AggregateException: One or more errors occurred. ---> System.ArgumentException: 'NoneType' value cannot be converted to System.Double in me
thod Void .ctor(Double) ---> Python.Runtime.PythonException: 'NoneType' value cannot be converted to System.Double
--- End of inner exception stack trace ---
--- End of inner exception stack trace ---
---> (Inner Exception #0) System.ArgumentException: 'NoneType' value cannot be converted to System.Double in method Void .ctor(Double) ---> Python
.Runtime.PythonException: 'NoneType' value cannot be converted to System.Double
--- End of inner exception stack trace ---<---
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 3251, in run_code
exec(code_obj, self.user_global_ns, self.user_ns)
File "<ipython-input-3-3b78c20f70fb>", line 1, in <module>
Nullable[Double](None)
TypeError: No constructor matches given arguments: (<class 'NoneType'>)
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1934, in showtraceback
stb = value._render_traceback_()
AttributeError: 'TypeError' object has no attribute '_render_traceback_'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 3191, in run_ast_nodes
if await self.run_code(code, result, async_=asy):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 3268, in run_code
self.showtraceback(running_compiled_code=True)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1936, in showtraceback
stb = self.InteractiveTB.structured_traceback(etype,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 1105,
in structured_traceback
return FormattedTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 999, i
n structured_traceback
return VerboseTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 871, i
n structured_traceback
formatted_exceptions += self.format_exception_as_a_whole(etype, evalue, etb, lines_of_context,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 775, i
n format_exception_as_a_whole
assert etb is not None
AssertionError
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1934, in showtraceback
stb = value._render_traceback_()
AttributeError: 'AssertionError' object has no attribute '_render_traceback_'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 2814, in _run_cell
return runner(coro)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\async_helpers.py", line
129, in _pseudo_sync_runner
coro.send(None)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 3012, in run_cell_async
has_raised = await self.run_ast_nodes(code_ast.body, cell_name,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 3210, in run_ast_nodes
self.showtraceback()
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1936, in showtraceback
stb = self.InteractiveTB.structured_traceback(etype,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 1105,
in structured_traceback
return FormattedTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 999, i
n structured_traceback
return VerboseTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 871, i
n structured_traceback
formatted_exceptions += self.format_exception_as_a_whole(etype, evalue, etb, lines_of_context,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 775, i
n format_exception_as_a_whole
assert etb is not None
AssertionError
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1934, in showtraceback
stb = value._render_traceback_()
AttributeError: 'AssertionError' object has no attribute '_render_traceback_'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\larry.jones\AppData\Local\Programs\Python\Python38\lib\runpy.py", line 194, in _run_module_as_main
return _run_code(code, main_globals, None,
File "C:\Users\larry.jones\AppData\Local\Programs\Python\Python38\lib\runpy.py", line 87, in _run_code
exec(code, run_globals)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\Scripts\ipython.exe\__main__.py", line 7, in <module>
sys.exit(start_ipython())
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\__init__.py", line 123, in st
art_ipython
return launch_new_instance(argv=argv, **kwargs)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\traitlets\config\application.py", lin
e 846, in launch_instance
app.start()
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\terminal\ipapp.py", line 316,
in start
self.shell.mainloop()
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\terminal\interactiveshell.py"
, line 611, in mainloop
self.interact()
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\terminal\interactiveshell.py"
, line 604, in interact
self.run_cell(code, store_history=True)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 2768, in run_cell
result = self._run_cell(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 2819, in _run_cell
self.showtraceback(running_compiled_code=True)
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\interactiveshell.py", li
ne 1936, in showtraceback
stb = self.InteractiveTB.structured_traceback(etype,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 1105,
in structured_traceback
return FormattedTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 999, i
n structured_traceback
return VerboseTB.structured_traceback(
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 871, i
n structured_traceback
formatted_exceptions += self.format_exception_as_a_whole(etype, evalue, etb, lines_of_context,
File "C:\Users\larry.jones\AppData\Local\pypoetry\Cache\virtualenvs\libpy-QVeQv1xn-py3.8\lib\site-packages\IPython\core\ultratb.py", line 775, i
n format_exception_as_a_whole
assert etb is not None
AssertionError
If you suspect this is an IPython 8.0.1 bug, please report it at:
https://github.com/ipython/ipython/issues
or send an email to the mailing list at ipython-dev@python.org
You can print a more detailed traceback right now with "%tb", or use "%debug"
to interactively debug it.
Extra-detailed tracebacks for bug-reporting purposes can be enabled via:
%config Application.verbose_crash=True
Environment
Runtime Environment:
OS Name: Windows
OS Version: 10.0.19044
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\6.0.101\
Details
I was trying to invoke a C# function with an argument of type Nullable. Python.NET reported that it could find no function matching the arguments. Eventually, I tried to test the fix for issue #460.
Minimal, Complete, and Verifiable example
this will help us understand the issue.
I also tried testing against pythonnet 3.0.0.a2. I see the following stack trace.