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).