bpo-37497: Add inspect.Signature.from_text(). #14579
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ericsnowcurrently
changed the title
| @@ -1976,7 +1990,9 @@ def _signature_fromstr(cls, obj, s, skip_bound_arg=True): | |||
| module = None | |||
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| if not isinstance(module, ast.Module): | |||
| raise ValueError("{!r} builtin has invalid signature".format(obj)) | |||
| exc = ValueError(f"invalid signature {text!r}") | |||
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Commenting the if block on master and in this PR has no test failure so I guess this code was not tested. Perhaps a test could be added where __text_signature__ has a invalid syntax as signature to see if ValueError is raised like below :
def test_python_function_invalid_text_signature(self):
def func(*args, **kwargs):
pass
func.__text_signature__ = '($self, **kwargs, a)'
with self.assertRaises(ValueError) as e:
sig = inspect.signature(func)
| @@ -550,7 +550,7 @@ The Signature object represents the call signature of a callable object and its | |||
| return annotation. To retrieve a Signature object, use the :func:`signature` | |||
| function. | |||
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| .. function:: signature(callable, \*, follow_wrapped=True) | |||
| .. function:: signature(callable_or_text, \*, follow_wrapped=True) | |||
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Sorry, I don't like the signature() function to accept both callables and text. This introduces extra complexity to the API for a very narrow use case.
It also makes the function too dynamic: currently, if a text value is passed to signature() by mistake the user would get an exception saying that a callable was expected. With this patch they'll likely get a ParseError.
IMO a public documented Signature.from_text() API is enough.
| clean_signature, self_parameter, last_positional_only = \ | ||
| _signature_strip_non_python_syntax(s) | ||
| (clean_signature, self_parameter, last_positional_only | ||
| ) = _signature_strip_non_python_syntax(text) |
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When you're done making the requested changes, leave the comment: |
https://bugs.python.org/issue37497