Adding tests to encoder.py (#4536)

tests/test_encoders.py

+from datetime import date, datetime, timedelta, tzinfo
+from decimal import Decimal
+from uuid import uuid4
+
+from django.test import TestCase
+
+from rest_framework.utils.encoders import JSONEncoder
+
+
+class JSONEncoderTests(TestCase):
+    """
+    Tests the JSONEncoder method
+    """
+
+    def setUp(self):
+        self.encoder = JSONEncoder()
+
+    def test_encode_decimal(self):
+        """
+        Tests encoding a decimal
+        """
+        d = Decimal(3.14)
+        self.assertEqual(d, float(d))
+
+    def test_encode_datetime(self):
+        """
+        Tests encoding a datetime object
+        """
+        current_time = datetime.now()
+        self.assertEqual(self.encoder.default(current_time), current_time.isoformat())
+
+    def test_encode_time(self):
+        """
+        Tests encoding a timezone
+        """
+        current_time = datetime.now().time()
+        self.assertEqual(self.encoder.default(current_time), current_time.isoformat()[:12])
+
+    def test_encode_time_tz(self):
+        """
+        Tests encoding a timezone aware timestamp
+        """
+
+        class UTC(tzinfo):
+            """
+            Class extending tzinfo to mimic UTC time
+            """
+            def utcoffset(self, dt):
+                return timedelta(0)
+
+            def tzname(self, dt):
+                return "UTC"
+
+            def dst(self, dt):
+                return timedelta(0)
+
+        current_time = datetime.now().time()
+        current_time = current_time.replace(tzinfo=UTC())
+        with self.assertRaises(ValueError):
+            self.encoder.default(current_time)
+
+    def test_encode_date(self):
+        """
+        Tests encoding a date object
+        """
+        current_date = date.today()
+        self.assertEqual(self.encoder.default(current_date), current_date.isoformat())
+
+    def test_encode_timedelta(self):
+        """
+        Tests encoding a timedelta object
+        """
+        delta = timedelta(hours=1)
+        self.assertEqual(self.encoder.default(delta), str(delta.total_seconds()))
+
+    def test_encode_uuid(self):
+        """
+        Tests encoding a UUID object
+        """
+        unique_id = uuid4()
+        self.assertEqual(self.encoder.default(unique_id), str(unique_id))