diff options
Diffstat (limited to 'Lib/datetime.py')
| -rw-r--r-- | Lib/datetime.py | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/Lib/datetime.py b/Lib/datetime.py index db13b12ef3..5ba2ddb7ab 100644 --- a/Lib/datetime.py +++ b/Lib/datetime.py @@ -316,6 +316,14 @@ def _divide_and_round(a, b): return q +def _round_half_up(x): + """Round to nearest with ties going away from zero.""" + if x >= 0.0: + return _math.floor(x + 0.5) + else: + return _math.ceil(x - 0.5) + + class timedelta: """Represent the difference between two datetime objects. @@ -399,7 +407,7 @@ class timedelta: # secondsfrac isn't referenced again if isinstance(microseconds, float): - microseconds = round(microseconds + usdouble) + microseconds = _round_half_up(microseconds + usdouble) seconds, microseconds = divmod(microseconds, 1000000) days, seconds = divmod(seconds, 24*3600) d += days @@ -410,7 +418,7 @@ class timedelta: days, seconds = divmod(seconds, 24*3600) d += days s += seconds - microseconds = round(microseconds + usdouble) + microseconds = _round_half_up(microseconds + usdouble) assert isinstance(s, int) assert isinstance(microseconds, int) assert abs(s) <= 3 * 24 * 3600 @@ -1376,7 +1384,7 @@ class datetime(date): converter = _time.localtime if tz is None else _time.gmtime t, frac = divmod(t, 1.0) - us = int(frac * 1e6) + us = _round_half_up(frac * 1e6) # If timestamp is less than one microsecond smaller than a # full second, us can be rounded up to 1000000. In this case, @@ -1396,7 +1404,7 @@ class datetime(date): def utcfromtimestamp(cls, t): """Construct a naive UTC datetime from a POSIX timestamp.""" t, frac = divmod(t, 1.0) - us = int(frac * 1e6) + us = _round_half_up(frac * 1e6) # If timestamp is less than one microsecond smaller than a # full second, us can be rounded up to 1000000. In this case, |