dav_events: improved Iso8601Serializer and its tests

dav_events/converters.py

@@ -2,7 +2,6 @@ import datetime
 import logging
 import re
 import pytz
-from six import string_types
 
 logger = logging.getLogger(__name__)
 
@@ -24,15 +23,17 @@ class Iso8601Serializer:
                      r')?'
                      r'(?P<offset>(?P<offdir>[\-+])(?P<offhours>([01][0-9])|(2[0123]))(:(?P<offmins>[0-5][0-9]))?)?$')
 
-    def __init__(self, instance=None, text=None):
-        if instance is not None:
-            self.instance = instance
-        elif text is not None:
-            self.instance = Iso8601Serializer.deserialize(text)
+    def __init__(self, value):
+        if isinstance(value, datetime.datetime) \
+                or isinstance(value, datetime.date) \
+                or isinstance(value, datetime.time):
+            dt_obj = value
+        else:
+            dt_obj = Iso8601Serializer.deserialize(value)
+        self._serialized = Iso8601Serializer.serialize(dt_obj)
 
-    @property
-    def str(self):
-        return Iso8601Serializer.serialize(self.instance)
+    def __str__(self):
+        return self._serialized
 
     @classmethod
     def serialize(cls, value, ignore_unsupported_input=False):
@@ -55,32 +56,43 @@ class Iso8601Serializer:
     @classmethod
     def deserialize(cls, value, ignore_unsupported_input=False):
         prefix = '{marker}{sep}'.format(marker=cls.marker, sep=cls.separator)
-        if isinstance(value, string_types) and value.startswith(prefix):
-            haystack = value[len(prefix):]
-            m = cls._re.match(haystack)
-            if m is not None:
-                gd = m.groupdict()
-                if gd['hour'] is None:
-                    value = datetime.date(int(gd['year']), int(gd['mon']), int(gd['day']))
-                elif gd['year'] is None:
-                    value = datetime.time(hour=int(gd['hour']), minute=int(gd['min']), second=int(gd['sec']))
+
+        if not isinstance(value, str):
+            if ignore_unsupported_input:
+                return value
+            raise TypeError('Expected string type, not {}'.format(value.__class__.__name__))
+
+        if not value.startswith(prefix):
+            if ignore_unsupported_input:
+                return value
+            raise ValueError('String must begin with \'{prefix}\''.format(prefix=prefix))
+
+        haystack = value[len(prefix):]
+        match = cls._re.match(haystack)
+
+        if match is None:
+            if ignore_unsupported_input:
+                return value
+            raise ValueError('Format not recognized \'{str}\''.format(str=haystack))
+
+        gd = match.groupdict()
+        if gd['hour'] is None:
+            value = datetime.date(int(gd['year']), int(gd['mon']), int(gd['day']))
+        elif gd['year'] is None:
+            value = datetime.time(hour=int(gd['hour']), minute=int(gd['min']), second=int(gd['sec']))
+        else:
+            value = datetime.datetime(int(gd['year']), int(gd['mon']), int(gd['day']),
+                                      hour=int(gd['hour']), minute=int(gd['min']), second=int(gd['sec']))
+            if gd['offset'] is not None:
+                offset = datetime.timedelta(hours=int(gd['offhours']))
+                if gd['offmins'] is not None:
+                    offset += datetime.timedelta(minutes=int(gd['offmins']))
+                if gd['offdir'] == '+':
+                    value -= offset
+                elif gd['offdir'] == '-':
+                    value += offset
                 else:
-                    value = datetime.datetime(int(gd['year']), int(gd['mon']), int(gd['day']),
-                                              hour=int(gd['hour']), minute=int(gd['min']), second=int(gd['sec']))
-                    if gd['offset'] is not None:
-                        offset = datetime.timedelta(hours=int(gd['offhours']))
-                        if gd['offmins'] is not None:
-                            offset += datetime.timedelta(minutes=int(gd['offmins']))
-                        if gd['offdir'] == '+':
-                            value -= offset
-                        elif gd['offdir'] == '-':
-                            value += offset
-                        else:
-                            raise ValueError('Offset format not recognized \'{str}\''.format(str=gd['offset']))
-                        value = value.replace(tzinfo=pytz.UTC)
-            elif not ignore_unsupported_input:
-                raise ValueError('Format not recognized \'{str}\''.format(str=haystack))
-        elif not ignore_unsupported_input:
-            raise ValueError('Expected string type,'
-                             ' not {}'.format(value.__class__.__name__))
+                    raise ValueError('Offset format not recognized \'{str}\''.format(str=gd['offset']))
+                value = value.replace(tzinfo=pytz.UTC)
+
         return value

dav_events/tests/test_converters.py

@@ -27,7 +27,44 @@ class Iso8601SerializerTestCase(TestCase):
                 obj = datetime.datetime.combine(date, time)
                 yield (obj, text)
 
-    def test_serialize(self):
+    def test_init_without_arg(self):
+        with self.assertRaises(TypeError) as cm:
+            _ = Iso8601Serializer()
+        self.assertEqual(str(cm.exception), 'Iso8601Serializer.__init__()'
+                                            ' missing 1 required positional argument: \'value\'')
+
+    def test_init_with_date(self):
+        date_obj = datetime.date(1976, 2, 1)
+        serializer = Iso8601Serializer(date_obj)
+        self.assertEqual(str(serializer), 'ISO8601:1976-02-01')
+
+    def test_init_with_datetime(self):
+        datetime_obj = datetime.datetime(1976, 2, 1, 12, 34, 56)
+        serializer = Iso8601Serializer(datetime_obj)
+        self.assertEqual(str(serializer), 'ISO8601:1976-02-01T12:34:56')
+
+    def test_init_with_time(self):
+        time_obj = datetime.time(12, 34, 56)
+        serializer = Iso8601Serializer(time_obj)
+        self.assertEqual(str(serializer), 'ISO8601:12:34:56')
+
+    def test_init_with_valid_text(self):
+        text = 'ISO8601:1976-02-01'
+        serializer = Iso8601Serializer(text)
+        self.assertEqual(str(serializer), text)
+
+    def test_init_with_invalid_format(self):
+        text = 'ISO8601:02.01.1976'
+        with self.assertRaises(ValueError) as cm:
+            _ = Iso8601Serializer(text)
+        self.assertEqual(str(cm.exception), 'Format not recognized \'02.01.1976\'')
+
+    def test_init_with_invalid_string(self):
+        text = '1976-02-01'
+        with self.assertRaisesRegex(ValueError, 'String must begin with \'ISO8601:\''):
+            _ = Iso8601Serializer(text)
+
+    def test_serialize_valid(self):
         test_data = []
 
         # Check date objects
@@ -43,10 +80,12 @@ class Iso8601SerializerTestCase(TestCase):
             serialized = Iso8601Serializer.serialize(obj)
             self.assertEqual(serialized, expected)
 
-        # Check invalid input
+    def test_serialize_invalid(self):
         invalid_values = (
-            None, True, False,
-            '2019-03-01',
+            None,
+            True,
+            False,
+            'ISO8601:1976-02-01',
         )
         for value in invalid_values:
             emsg = ('Expected datetime.datetime, datetime.date or datetime.time,'
@@ -56,7 +95,7 @@ class Iso8601SerializerTestCase(TestCase):
             serialized = Iso8601Serializer.serialize(value, ignore_unsupported_input=True)
             self.assertEqual(serialized, value)
 
-    def test_deserialize(self):
+    def test_deserialize_valid(self):
         test_data = []
 
         # Check '<YYYY>-<MM>-<DD>' format
@@ -71,3 +110,18 @@ class Iso8601SerializerTestCase(TestCase):
             deserialized = Iso8601Serializer.deserialize(text)
             self.assertIsInstance(deserialized, obj.__class__)
             self.assertEqual(deserialized, obj)
+
+    def test_deserialize_invalid(self):
+        invalid_data = (
+            (None, TypeError, 'Expected string type, not NoneType'),
+            (True, TypeError, 'Expected string type, not bool'),
+            (False, TypeError, 'Expected string type, not bool'),
+            ('1976-02-01', ValueError, 'String must begin with \'ISO8601:\''),
+            ('ISO8601:02.01.1976', ValueError, 'Format not recognized \'02.01.1976\''),
+        )
+        for value, expected_exception, expected_msg in invalid_data:
+            with self.assertRaisesRegex(expected_exception, expected_msg):
+                Iso8601Serializer.deserialize(value)
+            serialized = Iso8601Serializer.deserialize(value, ignore_unsupported_input=True)
+            self.assertEqual(serialized, value)
+