QUERY · ISSUE

int.to_bytes and int.from_bytes: signed parameter not implemented

openby Brun059opened 2024-07-03updated 2024-08-28

bugpy-core

Port, board and/or hardware

esp32-WROOM

MicroPython version

MicroPython v1.23.0 on 2024-06-02; Generic ESP32 module with ESP32

Reproduction

in micropython

int.from_bytes(b'\xFF\xFF' , 'big' , True)   --->  65535

in Python 3.11.4

int.from_bytes(b'\xFF\xFF' , byteorder='big' , signed=True)   ---> -1

Expected behaviour

Expected to return -1
according to https://docs.python.org/3/library/stdtypes.html#int.from_bytes

Observed behaviour

returns 65535 which is equivalent to signed=False

Additional Information

No, I've provided everything above.

Code of Conduct

Yes, I agree

CANDIDATE · ISSUE

int.to_bytes and int.from_bytes implementations incomplete

closedby khoulihanopened 2014-06-11updated 2024-08-28

These methods have the following comments in them:

// TODO: Support long ints
// TODO: Support byteorder param
// TODO: Support signed param

I encountered this when trying to convert an int to big-endian bytes, but to_bytes returned little-endian bytes instead. from_bytes also apparently only supports little-endian bytes.

Assessment

S Sonnet · high

Both issues report the same root cause: the signed parameter is not implemented in int.from_bytes() and int.to_bytes(). Issue #682 is the original broader report that explicitly cites // TODO: Support signed param in the source, along with missing byteorder and long int support. Issue #15399 is a narrower, newer report focusing specifically on the still-unresolved signed parameter with a clear CPython reproduction case. The byteorder TODO from #682 has since been addressed (the query reporter's code uses 'big' successfully for the unsigned case), leaving signed as the outstanding item — which is exactly what #15399 reports. Same code (py/objint.c), same missing feature.

Suggested action

Close #15399 as a duplicate of #682 (older issue). #15399 has better reproduction steps for the signed-specific case, so consider adding its example to #682's description or linking it there before closing.