Internal AttributeError when accessing invalid attribute in Python

[PeterJCLaw]

Describe the Bug

If you happen to typo the name of a method or attribute in your Python controller you get an error which appears to come from the Webots controller rather than your code.

Steps to Reproduce

from controller import Robot

Robot().oops

results in:

Traceback (most recent call last):
  File "demo.py", line 3, in <module>
    Robot().oops
  File "/usr/local/webots/lib/controller/python36/controller.py", line 1701, in <lambda>
    __getattr__ = lambda self, name: _swig_getattr(self, Node, name)
  File "/usr/local/webots/lib/controller/python36/controller.py", line 88, in _swig_getattr
    return _swig_getattr_nondynamic(self, class_type, name, 0)
  File "/usr/local/webots/lib/controller/python36/controller.py", line 83, in _swig_getattr_nondynamic
    return object.__getattr__(self, name)
AttributeError: type object 'object' has no attribute '__getattr__'

Expected behavior

While AttributeError is correct here, I would expect that it would have the proper name of the attribute which was being attempted to access (i.e: oops in the above).

System

• Operating System: Ubuntu 18.04

Additional context

I'm not sure what the code in Webots' controller.py is trying to do, but as far as I can determine object.__getattr__ is always going to be an error -- there isn't a class method of that name in any version of Python.

If this is meant to always error, then a simple fix would be to change _swig_getattr_nondynamic like so:

-    if (not static):
-        return object.__getattr__(self, name)
-    else:
-        raise AttributeError(name)
+    raise AttributeError(name)

Alternatively, perhaps the function getattr is intended to be being used?

     if (not static):
-        return object.__getattr__(self, name)
+        return getattr(self, name)
     else:
         raise AttributeError(name)

[omichel]

That's probably an issue caused by SWIG, yet another good reason to create a Python API which doesn't rely on SWIG, see also #2385 about it.

[ygoumaz]

Closing this issue as it was fixed with the new Python API.