Properly serialize get_tags Response

`get_tags` route response was adding the `tags` property twice, which is
not the expected behaviour. This is an example of the previous
serialization of the `get_tags` route:

`{"tags":{"tags":{"u.example":{"order":0.55},"u.another":{"order":0.11}}}}`

The new serialization removes the outer `tags` property.

ruma-client-api/CHANGELOG.md

@@ -4,6 +4,7 @@ Bug fixes:
 
 * Fix deserialization of `r0::room::get_room_event::Response`
 * More missing fields in `r0::sync::sync_events::Response` can be deserialized
+* Fix `get_tags::Response` serialization
 
 Breaking changes:
 

ruma-client-api/src/r0/tag/get_tags.rs

@@ -1,7 +1,7 @@
 //! [GET /_matrix/client/r0/user/{userId}/rooms/{roomId}/tags](https://matrix.org/docs/spec/client_server/r0.6.0#get-matrix-client-r0-user-userid-rooms-roomid-tags)
 
 use ruma_api::ruma_api;
-use ruma_events::{tag::TagEventContent, EventJson};
+use ruma_events::tag::Tags;
 use ruma_identifiers::{RoomId, UserId};
 
 ruma_api! {
@@ -26,8 +26,43 @@ ruma_api! {
 
     response: {
         /// The user's tags for the room.
-        pub tags: EventJson<TagEventContent>,
+        pub tags: Tags,
     }
 
     error: crate::Error
 }
+
+#[cfg(test)]
+mod tests {
+    use serde_json::json;
+
+    use super::Response;
+    use ruma_events::tag::{TagInfo, Tags};
+    use std::convert::TryFrom;
+
+    #[test]
+    fn test_serializing_get_tags_response() {
+        let mut tags = Tags::new();
+        tags.insert("m.favourite".to_string(), TagInfo { order: Some(0.25) });
+        tags.insert("u.user_tag".to_string(), TagInfo { order: Some(0.11) });
+        let response = Response { tags };
+
+        let http_response = http::Response::<Vec<u8>>::try_from(response).unwrap();
+
+        let json_response: serde_json::Value =
+            serde_json::from_slice(http_response.body()).unwrap();
+        assert_eq!(
+            json_response,
+            json!({
+                "tags": {
+                    "m.favourite": {
+                        "order": 0.25,
+                    },
+                    "u.user_tag": {
+                        "order": 0.11,
+                    }
+                }
+            })
+        );
+    }
+}

ruma-events/src/tag.rs

@@ -9,13 +9,15 @@ use crate::BasicEvent;
 
 /// Informs the client of tags on a room.
 pub type TagEvent = BasicEvent<TagEventContent>;
+/// Map of tag names to tag info.
+pub type Tags = BTreeMap<String, TagInfo>;
 
 /// The payload for `TagEvent`.
 #[derive(Clone, Debug, Deserialize, Serialize, BasicEventContent)]
 #[ruma_event(type = "m.tag")]
 pub struct TagEventContent {
     /// A map of tag names to tag info.
-    pub tags: BTreeMap<String, TagInfo>,
+    pub tags: Tags,
 }
 
 /// Information about a tag.