Consider this example:
>>> def a(p, /, a, b=2, *, f): ...
...
>>> import inspect
>>> inspect.getcallargs(a, p=1, a=2, b=3, f=4)
{'p': 1, 'a': 2, 'b': 3, 'f': 4}Compare it with the runtime:
>>> def a(p, /, a, b=2, *, f): ...
...
>>> a(p=1, a=2, b=3, f=4)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: a() got some positional-only arguments passed as keyword arguments: 'p'
And with inspect.signature.bind:
>>> inspect.signature(a).bind(p=1, a=2, b=3, f=4)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/sobolev/Desktop/cpython/Lib/inspect.py", line 3294, in bind
return self._bind(args, kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/sobolev/Desktop/cpython/Lib/inspect.py", line 3186, in _bind
raise TypeError(msg) from None
TypeError: 'p' parameter is positional only, but was passed as a keywordThe issue itself is not easy to fix, because inside getcallargs uses getfullargspec, which does not differentiate pos-only from pos-or-keyword:
|
spec = getfullargspec(func) |
|
args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = spec |
So, we cannot know that p is pos-only.
Note that inspect.getcallargs is deprecated in the docs.
So, I propose deprecating getcallargs with a DeprecationWarning in 3.13.
Consider this example:
Compare it with the runtime:
And with
inspect.signature.bind:The issue itself is not easy to fix, because inside
getcallargsusesgetfullargspec, which does not differentiate pos-only from pos-or-keyword:cpython/Lib/inspect.py
Lines 1582 to 1583 in 39ef93e
So, we cannot know that
pis pos-only.Note that
inspect.getcallargsis deprecated in the docs.So, I propose deprecating
getcallargswith aDeprecationWarningin3.13.