Fixed microsecond rounding in python version of utcfromtimestamp
diff --git a/Lib/datetime.py b/Lib/datetime.py
index 23ded3e..d640f75 100644
--- a/Lib/datetime.py
+++ b/Lib/datetime.py
@@ -1379,12 +1379,17 @@
@classmethod
def utcfromtimestamp(cls, t):
"Construct a UTC datetime from a POSIX timestamp (like time.time())."
- if 1 - (t % 1.0) < 0.000001:
- t = float(int(t)) + 1
- if t < 0:
- t -= 1
+ t, frac = divmod(t, 1.0)
+ us = round(frac * 1e6)
+
+ # If timestamp is less than one microsecond smaller than a
+ # full second, us can be rounded up to 1000000. In this case,
+ # roll over to seconds, otherwise, ValueError is raised
+ # by the constructor.
+ if us == 1000000:
+ t += 1
+ us = 0
y, m, d, hh, mm, ss, weekday, jday, dst = _time.gmtime(t)
- us = int((t % 1.0) * 1000000)
ss = min(ss, 59) # clamp out leap seconds if the platform has them
return cls(y, m, d, hh, mm, ss, us)
diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
index 7adf54c..0ee544b 100644
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -1729,10 +1729,10 @@
def test_microsecond_rounding(self):
# Test whether fromtimestamp "rounds up" floats that are less
# than 1/2 microsecond smaller than an integer.
- self.assertEqual(self.theclass.fromtimestamp(0.9999999),
- self.theclass.fromtimestamp(1))
- self.assertEqual(self.theclass.fromtimestamp(0.99999949).microsecond,
- 999999)
+ for fts in [self.theclass.fromtimestamp,
+ self.theclass.utcfromtimestamp]:
+ self.assertEqual(fts(0.9999999), fts(1))
+ self.assertEqual(fts(0.99999949).microsecond, 999999)
def test_insane_fromtimestamp(self):
# It's possible that some platform maps time_t to double,