Closed
Description
Assigning a negative value to an unsigned integer member can emit a RuntimeWarning.
$ ./python -Wa
>>> import _testcapi
>>> ts = _testcapi._test_structmembersType_NewAPI()
>>> ts.T_UBYTE = -42
<stdin>:1: RuntimeWarning: Truncation of value to unsigned char
>>> ts.T_USHORT = -42
<stdin>:1: RuntimeWarning: Truncation of value to unsigned short
>>> ts.T_UINT = -42
<stdin>:1: RuntimeWarning: Writing negative value into unsigned field
<stdin>:1: RuntimeWarning: Truncation of value to unsigned int
>>> ts.T_ULONG = -42
<stdin>:1: RuntimeWarning: Writing negative value into unsigned field
(And for T_ULONGLONG it raises an OverflowError, but this is perhaps another issue).
The first issue is that it emits two warnings for T_UINT. It is also weird that warnings are different.
The second issue is that if the value is not an int subclass, it emits a warning also for positive values for T_UINT and T_ULONG:
>>> class Index:
... def __init__(self, value):
... self.value = value
... def __index__(self):
... return self.value
...
>>> ts.T_UBYTE = Index(42)
>>> ts.T_USHORT = Index(42)
>>> ts.T_UINT = Index(42)
<stdin>:1: RuntimeWarning: Writing negative value into unsigned field
>>> ts.T_ULONG = Index(42)
<stdin>:1: RuntimeWarning: Writing negative value into unsigned field
(No warning is emitted for assigning a negative index to T_ULONGLONG, but this is perhaps another issue).