module random: randint() range error #17930
Description
Port, board and/or hardware
rp2
MicroPython version
MicroPython v1.26.0 on 2025-08-09; Raspberry Pi Pico with RP2040
The upper limit of the randint(a,b) doesn't behave as described in the documentation.
Reproduction
#!/micropython
# -*- coding: UTF-8 -*-
# vim: fileencoding=utf-8: ts=4: sw=4: expandtab:
import random
print('random.randint(a, b)')
print(' Return a random integer in the range [a, b] (INCLUDING!)')
print()
for VALUE in (2**31-1, 2**31 ,2**32-1):
try:
print(f'Testing {VALUE}: ', end='')
print(f'{random.randint(0,VALUE)} OK')
except OverflowError as oe:
print(f'Exception: {oe} ({VALUE})')Expected behaviour
Expected to work up to the upper limit of 2³² - 1
Observed behaviour
random.randint(a, b)
Return a random integer in the range [a, b] (INCLUDING!)
Testing 2147483647: 2094930763 OK
Testing 2147483648: Exception: overflow converting long int to machine word (2147483648)
Testing 4294967295: Exception: overflow converting long int to machine word (4294967295)
Additional Information
No, I've provided everything above.
Code of Conduct
Yes, I agree