gh-141578: Improve overflow error messages in PyLong_AsLong and PyLong_AsInt

[mohsinm-dev]

Replace generic overflow messages with specific ones that indicate whether the value exceeds maximum or minimum bounds.

Fixes #141578

• Issue: Provide custom error messages for overflows in PyLong_AsLong/PyLong_AsInt() #141578

[skirpichev]

CC @serhiy-storchaka

[chris-eibl]

Maybe 'too small' reads better here (and below)?

[skirpichev]

Could you be more precise? Replacing "too large" with "too small" will be just plain wrong right here.

[chris-eibl]

We are in the negative case here and "too large" combined with "less than" rings a bell for me. Maybe just splitting hairs (or I am completely mistaken).

[skirpichev]

My english is bad, so I trust your judgement.

Though, I don't see a problem so far. This exception supposed to
mean: value too large (by magnitude) for long, it would be < LONG_MIN.

Suggested change

	"Python int too large to convert to C long: "
	"Python int magnitude too large to convert to C long: "

?

[chris-eibl]

See Serhiy's comment below. I agree it would be better to just have simpler and unified messages.

[serhiy-storchaka]

In Python/getargs.c, other messages are used, like "signed short integer is less than minimum". I think it is incorrect (signed short integer cannot be less than SHRT_MIN). "integer is less than minimum for C short int" looks more correct.

And some error messages are simply "integer value out of range" because when we use PyLong_AsNativeBytes() we cannot know whether it is too large or too small.

It would be better to produce unified error messages in PyLong_As*(), PyArg_Parse*(), etc.

[skirpichev]

integer is less than minimum for C short int

Maybe it's better.

I.e.: PyErr_Format(..., "Python integer is less than minimum (%ld) for C long", LONG_MIN)

It would be better to produce unified error messages in PyLong_As*(), PyArg_Parse*(), etc.

I think this is out of the scope for this pr.

[chris-eibl]

I think this is out of the scope for this pr.

Not if we just use

cpython/Objects/longobject.c

Line 1259 in dc88dc0

PyErr_SetString(PyExc_OverflowError, "int too big to convert");

like in _PyLong_AsByteArray which is called in PyLong_AsLongLong.

Then at least those would be in sync?

[skirpichev]

Yes, just removing XXX marks is an alternative.