TypeError message uses name instead of qualname

Question

I find the following behavior:

>>> def f():
...     def g(a,b):
...         return a+b
...     return g
>>> f().__name__
... 'g'
>>> f().__qualname__
... 'f.<locals>.g'
>>> f()(2)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: g() missing 1 required positional argument: 'b'

I would like the error message to show the __qualname__ of the function involved instead of just the __name__. This is afaik also the recommended practice when writing such messages yourself.

Can I do anything about this (e.g. configuration on startup)? Or is this a bug/feature?

Showing the qualname would make debugging a lot easier, especially when working with decorators or lambdas.

---

python 3.6.1

Answer 1

This isn't configurable; it's hard coded in the interpreter internals. If you feel strongly about it, file a bug with the CPython folks. Given that __qualname__ is a newer feature, they may not have considered or gotten around to using it in this context.

Update: Looks like there is a bug already filed, but it hasn't seen any activity in the last couple years.