2 files changed, 34 insertions(+), 22 deletions(-)

M ftputil/host.py
M test/test_host.py

@@ 302,10 302,10 @@ class FTPHost(object):
         # Use a positive value for rounding.
         absolute_time_shift = abs(time_shift)
         signum = time_shift / absolute_time_shift
-        # Round it to hours. This code should also work for later Python
-        # versions because of the explicit `int`.
-        absolute_rounded_time_shift = \
-          int( (absolute_time_shift + 30*minute) / hour ) * hour
+        # Round absolute time shift to 15-minute units.
+        absolute_rounded_time_shift = (
+          int( (absolute_time_shift + (7.5*minute)) / (15.0*minute) ) *
+          (15.0*minute))
         # Return with correct sign.
         return signum * absolute_rounded_time_shift
 


@@ 325,13 325,13 @@ class FTPHost(object):
             raise ftputil.error.TimeShiftError(
                   "time shift abs({0:.2f} s) > 1 day".format(time_shift))
         # Test 2: Fail if the deviation between given time shift and
-        #         full hours is greater than a certain limit.
+        #         15-minute units is greater than a certain limit.
         maximum_deviation = 5 * minute
         if abs(time_shift - self.__rounded_time_shift(time_shift)) > \
            maximum_deviation:
             raise ftputil.error.TimeShiftError(
                     "time shift ({0:.2f} s) deviates more than {1:d} s "
-                    "from full hours".format(
+                    "from 15-minute units".format(
                       time_shift, int(maximum_deviation)))
 
     def synchronize_times(self):

@@ 12,6 12,7 @@ import posixpath
 import random
 import time
 import unittest
+import warnings
 
 import ftputil
 import ftputil.compat


@@ 380,12 381,12 @@ class TestTimeShift(unittest.TestCase):
           (      0,           0),
           (      0.1,         0),
           (     -0.1,         0),
-          (   1500,           0),
-          (  -1500,           0),
-          (   1800,        3600),
-          (  -1800,       -3600),
-          (   2000,        3600),
-          (  -2000,       -3600),
+          (   1500,        1800),
+          (  -1500,       -1800),
+          (   1800,        1800),
+          (  -1800,       -1800),
+          (   2000,        1800),
+          (  -2000,       -1800),
           ( 5*3600-100,  5*3600),
           (-5*3600+100, -5*3600)]
         for time_shift, expected_time_shift in test_data:


@@ 406,23 407,34 @@ class TestTimeShift(unittest.TestCase):
                           25*3600)
         self.assertRaises(ftputil.error.TimeShiftError, assert_time_shift,
                           -25*3600)
-        # Invalid time shift (too large deviation from full hours unacceptable)
+        # Invalid time shift (too large deviation from 15-minute units
+        # is unacceptable)
         self.assertRaises(ftputil.error.TimeShiftError, assert_time_shift,
-                          10*60)
+                          8*60)
         self.assertRaises(ftputil.error.TimeShiftError, assert_time_shift,
-                          -3600-10*60)
+                          -3600-8*60)
 
     def test_synchronize_times(self):
         """Test time synchronization with server."""
         host = test_base.ftp_host_factory(ftp_host_class=TimeShiftFTPHost,
                                           session_factory=TimeShiftMockSession)
-        # Valid time shift
-        host.path.set_mtime(time.time() + 3630)
-        host.synchronize_times()
-        self.assertEqual(host.time_shift(), 3600)
-        # Invalid time shift
-        host.path.set_mtime(time.time() + 3600+10*60)
-        self.assertRaises(ftputil.error.TimeShiftError, host.synchronize_times)
+        # Valid time shifts
+        test_data = [
+          (60*60+30,  60*60),
+          (60*60-100, 60*60),
+          (30*60+100, 30*60),
+          (45*60-100, 45*60),
+        ]
+        for measured_time_shift, expected_time_shift in test_data:
+            host.path.set_mtime(time.time() + measured_time_shift)
+            host.synchronize_times()
+            self.assertEqual(host.time_shift(), expected_time_shift)
+        # Invalid time shifts
+        measured_time_shifts = [60*60+8*60, 45*60-6*60]
+        for measured_time_shift in measured_time_shifts:
+            host.path.set_mtime(time.time() + measured_time_shift)
+            self.assertRaises(ftputil.error.TimeShiftError,
+                              host.synchronize_times)
 
     def test_synchronize_times_for_server_in_east(self):
         """Test for timestamp correction (see ticket #55)."""