Add some tests around embeds

tests/test_embeds.py

@@ -0,0 +1,32 @@
+from unittest import TestCase
+
+from datetime import datetime
+from disco.types.message import MessageEmbed
+
+
+class TestEmbeds(TestCase):
+    def test_empty_embed(self):
+        embed = MessageEmbed()
+        self.assertDictEqual(
+            embed.to_dict(),
+            {
+                'image': {},
+                'author': {},
+                'video': {},
+                'thumbnail': {},
+                'footer': {},
+                'fields': [],
+                'type': 'rich',
+            })
+
+    def test_embed(self):
+        embed = MessageEmbed(
+            title='Test Title',
+            description='Test Description',
+            url='https://test.url/'
+        )
+        obj = embed.to_dict()
+        self.assertEqual(obj['title'], 'Test Title')
+        self.assertEqual(obj['description'], 'Test Description')
+        self.assertEqual(obj['url'], 'https://test.url/')
+