events: Add event relation conversions

crates/ruma-events/CHANGELOG.md

@@ -13,6 +13,8 @@ Breaking changes:
 * Rename `relation` field in some events to `relates_to`
 * All events that support relations now have their own `Relation` types (the `room::relationships`
   module has been removed)
+  * The `room::encryption` relation type can represent any kind of relation and has `From`
+    implementations so any other relation can be converted to it
 
 Improvements:
 

crates/ruma-events/src/room/encrypted.rs

@@ -10,8 +10,11 @@ use ruma_identifiers::EventId;
 use serde::{Deserialize, Serialize};
 
 #[cfg(feature = "unstable-pre-spec")]
-use crate::room::message::Replacement;
+use crate::{key::verification, reaction, room::message::Replacement};
-use crate::{room::message::InReplyTo, MessageEvent};
+use crate::{
+    room::message::{self, InReplyTo},
+    MessageEvent,
+};
 
 mod relation_serde;
 
@@ -218,6 +221,32 @@ impl From<MegolmV1AesSha2ContentInit> for MegolmV1AesSha2Content {
     }
 }
 
+impl From<message::Relation> for Relation {
+    fn from(rel: message::Relation) -> Self {
+        match rel {
+            message::Relation::Reply { in_reply_to } => Self::Reply { in_reply_to },
+            #[cfg(feature = "unstable-pre-spec")]
+            message::Relation::Replacement(re) => Self::Replacement(re),
+        }
+    }
+}
+
+#[cfg(feature = "unstable-pre-spec")]
+impl From<reaction::Relation> for Relation {
+    fn from(rel: reaction::Relation) -> Self {
+        let reaction::Relation { event_id, emoji } = rel;
+        Self::Annotation(Annotation { event_id, key: emoji })
+    }
+}
+
+#[cfg(feature = "unstable-pre-spec")]
+impl From<verification::Relation> for Relation {
+    fn from(rel: verification::Relation) -> Self {
+        let verification::Relation { event_id } = rel;
+        Self::Reference(Reference { event_id })
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use matches::assert_matches;