Keep the casing pattern provided by the instance (#495)

activities/models/emoji.py

@@ -242,7 +242,7 @@ class Emoji(StatorModel):
         emoji_hits = FediverseHtmlParser(
             content, find_emojis=True, emoji_domain=domain
         ).emojis
-        emojis = sorted({emoji.lower() for emoji in emoji_hits})
+        emojis = sorted({emoji for emoji in emoji_hits})
         return list(
             cls.objects.filter(local=(domain is None) or domain.local)
             .usable(domain)
@@ -291,7 +291,7 @@ class Emoji(StatorModel):
                 raise ValueError("No mimetype on emoji JSON")
 
         # create
-        shortcode = name.lower().strip(":")
+        shortcode = name.strip(":")
         category = (icon.get("category") or "")[:100]
 
         if not domain.local:

tests/activities/models/test_emoji.py

@@ -42,3 +42,20 @@ def test_emoji_ingestion(identity):
         create=True,
     )
     assert emoji2.shortcode == "emoji2"
+
+    cased_emoji = Emoji.by_ap_tag(
+        identity.domain,
+        {
+            "icon": {
+                "type": "Image",
+                "url": "https://example.com/emoji/custom/CasedEmoji.png",
+                "mediaType": "image/png",
+            },
+            "id": "https://example.com/emoji/custom/CasedEmoji.png",
+            "nameMap": {"und": ":CasedEmoji:"},
+            "type": "Emoji",
+            "updated": "1970-01-01T00:00:00Z",
+        },
+        create=True,
+    )
+    assert cased_emoji.shortcode == "CasedEmoji"