Fix seconds inaccuracy for past datetimes

Fixes #152

Author: sdispater

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 - Fixed inaccuracy of `in_days()` method on DST transitions.
+- Fixed seconds inaccuracy for past datetimes.
 
 
 ## [1.3.0] - 2017-09-25

pendulum/_extensions/helpers.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+import math
 
 from ..constants import (
     EPOCH_YEAR,
@@ -27,7 +28,7 @@ def local_time(unix_time, utc_offset, microseconds):
     :rtype: tuple
     """
     year = EPOCH_YEAR
-    seconds = int(unix_time)
+    seconds = math.floor(unix_time)
 
     # Shift to a base year that is 400-year aligned.
     if seconds >= 0:

tests/pendulum_tests/test_construct.py

@@ -2,6 +2,9 @@
 
 import os
 import pytz
+
+import pendulum
+
 from datetime import datetime, timedelta
 from dateutil import tz
 from pendulum import Pendulum, PRE_TRANSITION, POST_TRANSITION
@@ -207,3 +210,8 @@ def test_init_fold_is_honored_if_explicit(self):
         d = Pendulum(2013, 3, 31, 2, 30, tzinfo='Europe/Paris', fold=1)
         self.assertPendulum(d, 2013, 3, 31, 3, 30)
         self.assertEqual(d.fold, 1)
+
+    def test_second_inaccuracy_on_past_datetimes(self):
+        dt = pendulum.create(1901, 12, 13, 0, 0, 0, 555555, tz='US/Central')
+
+        self.assertPendulum(dt, 1901, 12, 13, 0, 0, 0, 555555)