Python implementation of Decimal can hang in floor division

Bug report

# import decimal
import _pydecimal as decimal

_unbounded_dec_context = decimal.getcontext().copy()
_unbounded_dec_context.prec = decimal.MAX_PREC
_unbounded_dec_context.Emax = decimal.MAX_EMAX
_unbounded_dec_context.Emin = decimal.MIN_EMIN
_unbounded_dec_context.traps[decimal.Inexact] = 1 # sanity check
decimal.setcontext(_unbounded_dec_context)

x = decimal.Decimal('1')
y = x // 1

The C implementation evaluates the last line instantly, but the Python implementation hangs for a long time (infinitely?). The modulus operation has the same behavior.

cc @tim-one

Linked PRs

• gh-140044