Issue #11576: Fixed timedelta subtraction glitch on big timedelta values

This commit is contained in:
Alexander Belopolsky 2011-04-05 20:43:15 -04:00
commit 28deea1fa5
3 changed files with 19 additions and 8 deletions

View File

@ -485,7 +485,11 @@ class timedelta:
def __sub__(self, other):
if isinstance(other, timedelta):
return self + -other
# for CPython compatibility, we cannot use
# our __class__ here, but need a real timedelta
return timedelta(self._days - other._days,
self._seconds - other._seconds,
self._microseconds - other._microseconds)
return NotImplemented
def __rsub__(self, other):

View File

@ -383,6 +383,12 @@ class TestTimeDelta(HarmlessMixedComparison, unittest.TestCase):
for i in range(-10, 10):
eq((i*us/-3)//us, round(i/-3))
# Issue #11576
eq(td(999999999, 86399, 999999) - td(999999999, 86399, 999998),
td(0, 0, 1))
eq(td(999999999, 1, 1) - td(999999999, 1, 0),
td(0, 0, 1))
def test_disallowed_computations(self):
a = timedelta(42)

View File

@ -1801,13 +1801,14 @@ delta_subtract(PyObject *left, PyObject *right)
if (PyDelta_Check(left) && PyDelta_Check(right)) {
/* delta - delta */
PyObject *minus_right = PyNumber_Negative(right);
if (minus_right) {
result = delta_add(left, minus_right);
Py_DECREF(minus_right);
}
else
result = NULL;
/* The C-level additions can't overflow because of the
* invariant bounds.
*/
int days = GET_TD_DAYS(left) - GET_TD_DAYS(right);
int seconds = GET_TD_SECONDS(left) - GET_TD_SECONDS(right);
int microseconds = GET_TD_MICROSECONDS(left) -
GET_TD_MICROSECONDS(right);
result = new_delta(days, seconds, microseconds, 1);
}
if (result == Py_NotImplemented)