Closes issue bpo-5288: Allow tzinfo objects with sub-minute offsets. (#2896)

* Closes issue bpo-5288: Allow tzinfo objects with sub-minute offsets.

* bpo-5288: Implemented %z formatting of sub-minute offsets.

* bpo-5288: Removed mentions of the whole minute limitation on TZ offsets.

* bpo-5288: Removed one more mention of the whole minute limitation.

Thanks @csabella!

* Fix a formatting error in the docs

* Addressed review comments.

Thanks, @haypo.

1 files changed, 18 insertions, 9 deletions

diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
index 2200888..29b70e1 100644
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -255,14 +255,15 @@ class TestTimeZone(unittest.TestCase):
         self.assertEqual(timezone.min.utcoffset(None), -limit)
         self.assertEqual(timezone.max.utcoffset(None), limit)
 
-
     def test_constructor(self):
         self.assertIs(timezone.utc, timezone(timedelta(0)))
         self.assertIsNot(timezone.utc, timezone(timedelta(0), 'UTC'))
         self.assertEqual(timezone.utc, timezone(timedelta(0), 'UTC'))
+        for subminute in [timedelta(microseconds=1), timedelta(seconds=1)]:
+            tz = timezone(subminute)
+            self.assertNotEqual(tz.utcoffset(None) % timedelta(minutes=1), 0)
         # invalid offsets
-        for invalid in [timedelta(microseconds=1), timedelta(1, 1),
-                        timedelta(seconds=1), timedelta(1), -timedelta(1)]:
+        for invalid in [timedelta(1, 1), timedelta(1)]:
             self.assertRaises(ValueError, timezone, invalid)
             self.assertRaises(ValueError, timezone, -invalid)
 
@@ -301,6 +302,15 @@ class TestTimeZone(unittest.TestCase):
         self.assertEqual('UTC-00:01', timezone(timedelta(minutes=-1)).tzname(None))
         self.assertEqual('XYZ', timezone(-5 * HOUR, 'XYZ').tzname(None))
 
+        # Sub-minute offsets:
+        self.assertEqual('UTC+01:06:40', timezone(timedelta(0, 4000)).tzname(None))
+        self.assertEqual('UTC-01:06:40',
+                         timezone(-timedelta(0, 4000)).tzname(None))
+        self.assertEqual('UTC+01:06:40.000001',
+                         timezone(timedelta(0, 4000, 1)).tzname(None))
+        self.assertEqual('UTC-01:06:40.000001',
+                         timezone(-timedelta(0, 4000, 1)).tzname(None))
+
         with self.assertRaises(TypeError): self.EST.tzname('')
         with self.assertRaises(TypeError): self.EST.tzname(5)
 
@@ -2152,6 +2162,9 @@ class TestDateTime(TestDate):
         t = self.theclass(2004, 12, 31, 6, 22, 33, 47)
         self.assertEqual(t.strftime("%m %d %y %f %S %M %H %j"),
                                     "12 31 04 000047 33 22 06 366")
+        tz = timezone(-timedelta(hours=2, seconds=33, microseconds=123))
+        t = t.replace(tzinfo=tz)
+        self.assertEqual(t.strftime("%z"), "-020033.000123")
 
     def test_extract(self):
         dt = self.theclass(2002, 3, 4, 18, 45, 3, 1234)
@@ -2717,8 +2730,8 @@ class TZInfoBase:
             def utcoffset(self, dt): return timedelta(microseconds=61)
             def dst(self, dt): return timedelta(microseconds=-81)
         t = cls(1, 1, 1, tzinfo=C7())
-        self.assertRaises(ValueError, t.utcoffset)
-        self.assertRaises(ValueError, t.dst)
+        self.assertEqual(t.utcoffset(), timedelta(microseconds=61))
+        self.assertEqual(t.dst(), timedelta(microseconds=-81))
 
     def test_aware_compare(self):
         cls = self.theclass
@@ -4297,7 +4310,6 @@ class TestLocalTimeDisambiguation(unittest.TestCase):
         self.assertEqual(gdt.strftime("%c %Z"),
                          'Mon Jun 23 22:00:00 1941 UTC')
 
-
     def test_constructors(self):
         t = time(0, fold=1)
         dt = datetime(1, 1, 1, fold=1)
@@ -4372,7 +4384,6 @@ class TestLocalTimeDisambiguation(unittest.TestCase):
         self.assertEqual(t0.fold, 0)
         self.assertEqual(t1.fold, 1)
 
-
     @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
     def test_timestamp(self):
         dt0 = datetime(2014, 11, 2, 1, 30)
@@ -4390,7 +4401,6 @@ class TestLocalTimeDisambiguation(unittest.TestCase):
         s1 = t.replace(fold=1).timestamp()
         self.assertEqual(s0 + 1800, s1)
 
-
     @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
     def test_astimezone(self):
         dt0 = datetime(2014, 11, 2, 1, 30)
@@ -4406,7 +4416,6 @@ class TestLocalTimeDisambiguation(unittest.TestCase):
         self.assertEqual(adt0.fold, 0)
         self.assertEqual(adt1.fold, 0)
 
-
     def test_pickle_fold(self):
         t = time(fold=1)
         dt = datetime(1, 1, 1, fold=1)