common: Move prev_content into unsigned

crates/ruma-common/src/events.rs

@@ -188,13 +188,10 @@ pub mod video;
 
 #[cfg(feature = "unstable-msc2675")]
 pub use self::relation::Relations;
-#[doc(hidden)]
-#[cfg(feature = "compat")]
-pub use self::unsigned::{RedactedUnsignedWithPrevContent, UnsignedWithPrevContent};
 pub use self::{
     enums::*,
     event_kinds::*,
-    unsigned::{RedactedUnsigned, Unsigned},
+    unsigned::{MessageLikeUnsigned, RedactedUnsigned, StateUnsigned},
 };
 
 /// The base trait that all event content types implement.

crates/ruma-common/src/events/event_kinds.rs

@@ -5,8 +5,8 @@ use serde::{Deserialize, Serialize};
 
 use super::{
     EphemeralRoomEventType, EventContent, GlobalAccountDataEventType, MessageLikeEventType,
-    RedactedEventContent, RedactedUnsigned, RoomAccountDataEventType, StateEventType,
+    MessageLikeUnsigned, RedactedEventContent, RedactedUnsigned, RoomAccountDataEventType,
-    ToDeviceEventType, Unsigned,
+    StateEventType, StateUnsigned, ToDeviceEventType,
 };
 use crate::{EventId, MilliSecondsSinceUnixEpoch, RoomId, UserId};
 
@@ -63,7 +63,7 @@ pub struct MessageLikeEvent<C: EventContent<EventType = MessageLikeEventType>> {
     pub room_id: Box<RoomId>,
 
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: MessageLikeUnsigned,
 }
 
 /// A message-like event without a `room_id`.
@@ -85,7 +85,7 @@ pub struct SyncMessageLikeEvent<C: EventContent<EventType = MessageLikeEventType
     pub origin_server_ts: MilliSecondsSinceUnixEpoch,
 
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: MessageLikeUnsigned,
 }
 
 /// A redacted message-like event.
@@ -166,11 +166,8 @@ pub struct StateEvent<C: EventContent<EventType = StateEventType>> {
     /// affects.
     pub state_key: String,
 
-    /// Optional previous content for this event.
-    pub prev_content: Option<C>,
-
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: StateUnsigned<C>,
 }
 
 /// A state event without a `room_id`.
@@ -197,11 +194,8 @@ pub struct SyncStateEvent<C: EventContent<EventType = StateEventType>> {
     /// affects.
     pub state_key: String,
 
-    /// Optional previous content for this event.
-    pub prev_content: Option<C>,
-
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: StateUnsigned<C>,
 }
 
 /// A stripped-down state event, used for previews of rooms the user has been invited to.

crates/ruma-common/src/events/policy/rule/room.rs

@@ -27,7 +27,7 @@ mod tests {
         event_id,
         events::{
             policy::rule::{PolicyRuleEventContent, Recommendation},
-            Unsigned,
+            StateUnsigned,
         },
         room_id,
         serde::Raw,
@@ -42,13 +42,7 @@ mod tests {
             origin_server_ts: MilliSecondsSinceUnixEpoch(1_432_735_824_653_u64.try_into().unwrap()),
             room_id: room_id!("!jEsUZKDJdhlrceRyVU:example.org").to_owned(),
             state_key: "rule:#*:example.org".into(),
-            prev_content: None,
+            unsigned: StateUnsigned { age: Some(int!(1234)), ..StateUnsigned::default() },
-            unsigned: Unsigned {
-                age: Some(int!(1234)),
-                transaction_id: None,
-                #[cfg(feature = "unstable-msc2675")]
-                relations: None,
-            },
             content: PolicyRuleRoomEventContent(PolicyRuleEventContent {
                 entity: "#*:example.org".into(),
                 reason: "undesirable content".into(),

crates/ruma-common/src/events/room/canonical_alias.rs

@@ -44,7 +44,7 @@ mod tests {
     use serde_json::{from_value as from_json_value, json, to_value as to_json_value};
 
     use super::RoomCanonicalAliasEventContent;
-    use crate::events::{StateEvent, Unsigned};
+    use crate::events::{StateEvent, StateUnsigned};
 
     #[test]
     fn serialization_with_optional_fields_as_none() {
@@ -55,11 +55,10 @@ mod tests {
             },
             event_id: event_id!("$h29iv0s8:example.com").to_owned(),
             origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-            prev_content: None,
             room_id: room_id!("!dummy:example.com").to_owned(),
             sender: user_id!("@carl:example.com").to_owned(),
             state_key: "".into(),
-            unsigned: Unsigned::default(),
+            unsigned: StateUnsigned::default(),
         };
 
         let actual = to_json_value(&canonical_alias_event).unwrap();

crates/ruma-common/src/events/room/member.rs

@@ -387,7 +387,12 @@ impl RoomMemberEvent {
     ///
     /// [spec]: https://spec.matrix.org/v1.2/client-server-api/#mroommember
     pub fn membership_change(&self) -> MembershipChange {
-        membership_change(&self.content, self.prev_content.as_ref(), &self.sender, &self.state_key)
+        membership_change(
+            &self.content,
+            self.unsigned.prev_content.as_ref(),
+            &self.sender,
+            &self.state_key,
+        )
     }
 }
 
@@ -398,7 +403,12 @@ impl SyncStateEvent<RoomMemberEventContent> {
     ///
     /// [spec]: https://spec.matrix.org/v1.2/client-server-api/#mroommember
     pub fn membership_change(&self) -> MembershipChange {
-        membership_change(&self.content, self.prev_content.as_ref(), &self.sender, &self.state_key)
+        membership_change(
+            &self.content,
+            self.unsigned.prev_content.as_ref(),
+            &self.sender,
+            &self.state_key,
+        )
     }
 }
 
@@ -422,7 +432,7 @@ mod tests {
     use serde_json::{from_value as from_json_value, json};
 
     use super::{MembershipState, RoomMemberEventContent, SignedContent, ThirdPartyInvite};
-    use crate::events::StateEvent;
+    use crate::events::{StateEvent, StateUnsigned};
 
     #[test]
     fn serde_with_no_prev_content() {
@@ -455,7 +465,6 @@ mod tests {
                 sender,
                 state_key,
                 unsigned,
-                prev_content: None,
             } if event_id == "$h29iv0s8:example.com"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
                 && room_id == "!n8f893n9:example.com"
@@ -474,12 +483,14 @@ mod tests {
             },
             "event_id": "$h29iv0s8:example.com",
             "origin_server_ts": 1,
+            "room_id": "!n8f893n9:example.com",
+            "sender": "@carl:example.com",
+            "state_key": "example.com",
+            "unsigned": {
                 "prev_content": {
                     "membership": "join"
                 },
-            "room_id": "!n8f893n9:example.com",
+            },
-            "sender": "@carl:example.com",
-            "state_key": "example.com"
         });
 
         assert_matches!(
@@ -498,7 +509,7 @@ mod tests {
                 room_id,
                 sender,
                 state_key,
-                unsigned,
+                unsigned: StateUnsigned {
                     prev_content: Some(RoomMemberEventContent {
                         avatar_url: None,
                         displayname: None,
@@ -507,12 +518,13 @@ mod tests {
                         third_party_invite: None,
                         ..
                     }),
+                    ..
+                },
             } if event_id == "$h29iv0s8:example.com"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
                 && room_id == "!n8f893n9:example.com"
                 && sender == "@carl:example.com"
                 && state_key == "example.com"
-                && unsigned.is_empty()
         );
     }
 
@@ -565,7 +577,6 @@ mod tests {
                 sender,
                 state_key,
                 unsigned,
-                prev_content: None,
             } if avatar_url == "mxc://example.org/SEsfnsuifSDFSSEF"
                 && displayname == "Alice Margatroid"
                 && third_party_displayname == "alice"
@@ -590,10 +601,14 @@ mod tests {
         let json = json!({
             "type": "m.room.member",
             "content": {
-                "membership": "join"
+                "membership": "join",
             },
             "event_id": "$143273582443PhrSn:example.org",
             "origin_server_ts": 233,
+            "room_id": "!jEsUZKDJdhlrceRyVU:example.org",
+            "sender": "@alice:example.org",
+            "state_key": "@alice:example.org",
+            "unsigned": {
                 "prev_content": {
                     "avatar_url": "mxc://example.org/SEsfnsuifSDFSSEF",
                     "displayname": "Alice Margatroid",
@@ -605,16 +620,14 @@ mod tests {
                             "mxid": "@alice:example.org",
                             "signatures": {
                                 "magic.forest": {
-                                "ed25519:3": "foobar"
+                                    "ed25519:3": "foobar",
-                            }
+                                },
                             },
                             "token": "abc123"
-                    }
-                }
                         },
-            "room_id": "!jEsUZKDJdhlrceRyVU:example.org",
+                    },
-            "sender": "@alice:example.org",
+                },
-            "state_key": "@alice:example.org"
+            },
         });
 
         assert_matches!(
@@ -633,7 +646,7 @@ mod tests {
                 room_id,
                 sender,
                 state_key,
-                unsigned,
+                unsigned: StateUnsigned {
                     prev_content: Some(RoomMemberEventContent {
                         avatar_url: Some(avatar_url),
                         displayname: Some(displayname),
@@ -645,12 +658,13 @@ mod tests {
                         }),
                         ..
                     }),
+                    ..
+                },
             } if event_id == "$143273582443PhrSn:example.org"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(233))
                 && room_id == "!jEsUZKDJdhlrceRyVU:example.org"
                 && sender == "@alice:example.org"
                 && state_key == "@alice:example.org"
-                && unsigned.is_empty()
                 && avatar_url == "mxc://example.org/SEsfnsuifSDFSSEF"
                 && displayname == "Alice Margatroid"
                 && third_party_displayname == "alice"
@@ -662,80 +676,6 @@ mod tests {
                 }
                 && token == "abc123"
         );
-
-        #[cfg(feature = "compat")]
-        assert_matches!(
-            from_json_value::<StateEvent<RoomMemberEventContent>>(json!({
-                "type": "m.room.member",
-                "content": {
-                    "membership": "join"
-                },
-                "event_id": "$143273582443PhrSn:example.org",
-                "origin_server_ts": 233,
-                "prev_content": {
-                    "avatar_url": "",
-                    "displayname": "Alice Margatroid",
-                    "is_direct": true,
-                    "membership": "invite",
-                    "third_party_invite": {
-                        "display_name": "alice",
-                        "signed": {
-                            "mxid": "@alice:example.org",
-                            "signatures": {
-                                "magic.forest": {
-                                    "ed25519:3": "foobar"
-                                }
-                            },
-                            "token": "abc123"
-                        }
-                    }
-                },
-                "room_id": "!jEsUZKDJdhlrceRyVU:example.org",
-                "sender": "@alice:example.org",
-                "state_key": "@alice:example.org"
-            })).unwrap(),
-            StateEvent {
-                content: RoomMemberEventContent {
-                    avatar_url: None,
-                    displayname: None,
-                    is_direct: None,
-                    membership: MembershipState::Join,
-                    third_party_invite: None,
-                    ..
-                },
-                event_id,
-                origin_server_ts,
-                room_id,
-                sender,
-                state_key,
-                unsigned,
-                prev_content: Some(RoomMemberEventContent {
-                    avatar_url: None,
-                    displayname: Some(displayname),
-                    is_direct: Some(true),
-                    membership: MembershipState::Invite,
-                    third_party_invite: Some(ThirdPartyInvite {
-                        display_name: third_party_displayname,
-                        signed: SignedContent { mxid, signatures, token },
-                    }),
-                    ..
-                }),
-            } if event_id == "$143273582443PhrSn:example.org"
-                && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(233))
-                && room_id == "!jEsUZKDJdhlrceRyVU:example.org"
-                && sender == "@alice:example.org"
-                && state_key == "@alice:example.org"
-                && unsigned.is_empty()
-                && displayname == "Alice Margatroid"
-                && third_party_displayname == "alice"
-                && mxid == "@alice:example.org"
-                && signatures == btreemap! {
-                    server_name!("magic.forest").to_owned() => btreemap! {
-                        server_signing_key_id!("ed25519:3").to_owned() => "foobar".to_owned()
-                    }
-                }
-                && token == "abc123"
-        );
     }
 
     #[test]
@@ -771,7 +711,6 @@ mod tests {
                 sender,
                 state_key,
                 unsigned,
-                prev_content: None,
             } if event_id == "$h29iv0s8:example.com"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
                 && room_id == "!n8f893n9:example.com"

crates/ruma-common/src/events/room/message/reply.rs

@@ -299,7 +299,9 @@ fn formatted_or_plain_body<'a>(formatted: &'a Option<FormattedBody>, body: &'a s
 
 #[cfg(test)]
 mod tests {
-    use crate::{event_id, room_id, user_id};
+    use crate::{
+        event_id, events::MessageLikeUnsigned, room_id, user_id, MilliSecondsSinceUnixEpoch,
+    };
 
     use super::{RoomMessageEvent, RoomMessageEventContent};
 
@@ -310,9 +312,9 @@ mod tests {
                 content: RoomMessageEventContent::text_plain("multi\nline"),
                 event_id: event_id!("$1598361704261elfgc:localhost").to_owned(),
                 sender: user_id!("@alice:example.com").to_owned(),
-                origin_server_ts: crate::MilliSecondsSinceUnixEpoch::now(),
+                origin_server_ts: MilliSecondsSinceUnixEpoch::now(),
                 room_id: room_id!("!n8f893n9:example.com").to_owned(),
-                unsigned: crate::events::Unsigned::new(),
+                unsigned: MessageLikeUnsigned::new(),
             }),
             "> <@alice:example.com> multi\n> line"
         );

crates/ruma-common/src/events/room/name.rs

@@ -36,7 +36,7 @@ mod tests {
     use serde_json::{from_value as from_json_value, json, to_value as to_json_value};
 
     use super::RoomNameEventContent;
-    use crate::events::{StateEvent, Unsigned};
+    use crate::events::{StateEvent, StateUnsigned};
 
     #[test]
     fn serialization_with_optional_fields_as_none() {
@@ -44,11 +44,10 @@ mod tests {
             content: RoomNameEventContent { name: "The room name".try_into().ok() },
             event_id: event_id!("$h29iv0s8:example.com").to_owned(),
             origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-            prev_content: None,
             room_id: room_id!("!n8f893n9:example.com").to_owned(),
             sender: user_id!("@carl:example.com").to_owned(),
             state_key: "".into(),
-            unsigned: Unsigned::default(),
+            unsigned: StateUnsigned::default(),
         };
 
         let actual = to_json_value(&name_event).unwrap();
@@ -73,11 +72,14 @@ mod tests {
             content: RoomNameEventContent { name: "The room name".try_into().ok() },
             event_id: event_id!("$h29iv0s8:example.com").to_owned(),
             origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-            prev_content: Some(RoomNameEventContent { name: "The old name".try_into().ok() }),
             room_id: room_id!("!n8f893n9:example.com").to_owned(),
             sender: user_id!("@carl:example.com").to_owned(),
             state_key: "".into(),
-            unsigned: Unsigned { age: Some(int!(100)), ..Unsigned::default() },
+            unsigned: StateUnsigned {
+                age: Some(int!(100)),
+                prev_content: Some(RoomNameEventContent { name: "The old name".try_into().ok() }),
+                ..StateUnsigned::default()
+            },
         };
 
         let actual = to_json_value(&name_event).unwrap();
@@ -87,13 +89,13 @@ mod tests {
             },
             "event_id": "$h29iv0s8:example.com",
             "origin_server_ts": 1,
-            "prev_content": { "name": "The old name" },
             "room_id": "!n8f893n9:example.com",
             "sender": "@carl:example.com",
             "state_key": "",
             "type": "m.room.name",
             "unsigned": {
-                "age": 100
+                "age": 100,
+                "prev_content": { "name": "The old name" },
             }
         });
 

crates/ruma-common/src/events/room/pinned_events.rs

@@ -32,7 +32,7 @@ mod tests {
     use crate::{server_name, EventId, MilliSecondsSinceUnixEpoch, RoomId, UserId};
 
     use super::RoomPinnedEventsEventContent;
-    use crate::events::{StateEvent, Unsigned};
+    use crate::events::{StateEvent, StateUnsigned};
 
     #[test]
     fn serialization_deserialization() {
@@ -47,11 +47,10 @@ mod tests {
             content: content.clone(),
             event_id: EventId::new(server_name),
             origin_server_ts: MilliSecondsSinceUnixEpoch(1_432_804_485_886_u64.try_into().unwrap()),
-            prev_content: None,
             room_id: RoomId::new(server_name),
             sender: UserId::new(server_name),
             state_key: "".into(),
-            unsigned: Unsigned::default(),
+            unsigned: StateUnsigned::default(),
         };
 
         let serialized_event = serde_json::to_string(&event).unwrap();

crates/ruma-common/src/events/room/power_levels.rs

@@ -182,7 +182,7 @@ mod tests {
     use serde_json::{json, to_value as to_json_value};
 
     use super::{default_power_level, NotificationPowerLevels, RoomPowerLevelsEventContent};
-    use crate::events::{StateEvent, Unsigned};
+    use crate::events::{StateEvent, StateUnsigned};
 
     #[test]
     fn serialization_with_optional_fields_as_none() {
@@ -203,9 +203,8 @@ mod tests {
             },
             event_id: event_id!("$h29iv0s8:example.com").to_owned(),
             origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-            prev_content: None,
             room_id: room_id!("!n8f893n9:example.com").to_owned(),
-            unsigned: Unsigned::default(),
+            unsigned: StateUnsigned::default(),
             sender: user_id!("@carl:example.com").to_owned(),
             state_key: "".into(),
         };
@@ -246,8 +245,12 @@ mod tests {
             },
             event_id: event_id!("$h29iv0s8:example.com").to_owned(),
             origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
+            room_id: room_id!("!n8f893n9:example.com").to_owned(),
+            unsigned: StateUnsigned {
+                age: Some(int!(100)),
                 prev_content: Some(RoomPowerLevelsEventContent {
-                // Make just one field different so we at least know they're two different objects.
+                    // Make just one field different so we at least know they're two different
+                    // objects.
                     ban: int!(42),
                     events: btreemap! {
                         "m.dummy".into() => int!(42)
@@ -263,8 +266,8 @@ mod tests {
                     users_default: int!(42),
                     notifications: assign!(NotificationPowerLevels::new(), { room: int!(42) }),
                 }),
-            room_id: room_id!("!n8f893n9:example.com").to_owned(),
+                ..StateUnsigned::default()
-            unsigned: Unsigned { age: Some(int!(100)), ..Unsigned::default() },
+            },
             sender: user.to_owned(),
             state_key: "".into(),
         };
@@ -291,6 +294,12 @@ mod tests {
             },
             "event_id": "$h29iv0s8:example.com",
             "origin_server_ts": 1,
+            "room_id": "!n8f893n9:example.com",
+            "sender": "@carl:example.com",
+            "state_key": "",
+            "type": "m.room.power_levels",
+            "unsigned": {
+                "age": 100,
                 "prev_content": {
                     "ban": 42,
                     "events": {
@@ -307,14 +316,8 @@ mod tests {
                     "users_default": 42,
                     "notifications": {
                         "room": 42
-                }
                     },
-            "room_id": "!n8f893n9:example.com",
+                },
-            "sender": "@carl:example.com",
-            "state_key": "",
-            "type": "m.room.power_levels",
-            "unsigned": {
-                "age": 100
             }
         });
 

crates/ruma-common/src/events/room/redaction.rs

@@ -6,7 +6,7 @@ use ruma_macros::{Event, EventContent};
 use serde::{Deserialize, Serialize};
 
 use crate::{
-    events::{Redact, RedactContent, RedactedUnsigned, Unsigned},
+    events::{MessageLikeUnsigned, Redact, RedactContent, RedactedUnsigned},
     EventId, MilliSecondsSinceUnixEpoch, RoomId, UserId,
 };
 
@@ -33,7 +33,7 @@ pub struct RoomRedactionEvent {
     pub room_id: Box<RoomId>,
 
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: MessageLikeUnsigned,
 }
 
 impl Redact for RoomRedactionEvent {
@@ -103,7 +103,7 @@ pub struct SyncRoomRedactionEvent {
     pub origin_server_ts: MilliSecondsSinceUnixEpoch,
 
     /// Additional key-value pairs not signed by the homeserver.
-    pub unsigned: Unsigned,
+    pub unsigned: MessageLikeUnsigned,
 }
 
 impl Redact for SyncRoomRedactionEvent {

crates/ruma-common/src/events/unsigned.rs

@@ -1,15 +1,16 @@
 use js_int::Int;
 use serde::{Deserialize, Serialize};
+use serde_json::{from_str as from_json_str, value::RawValue as RawJsonValue};
 
 #[cfg(feature = "unstable-msc2675")]
 use super::relation::Relations;
-use super::room::redaction::SyncRoomRedactionEvent;
+use super::{room::redaction::SyncRoomRedactionEvent, EventContent, StateEventType};
-use crate::TransactionId;
+use crate::{serde::Raw, TransactionId};
 
-/// Extra information about an event that is not incorporated into the event's hash.
+/// Extra information about a message event that is not incorporated into the event's hash.
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
-pub struct Unsigned {
+pub struct MessageLikeUnsigned {
     /// The time in milliseconds that has elapsed since the event was sent.
     ///
     /// This field is generated by the local homeserver, and may be incorrect if the local time on
@@ -29,7 +30,7 @@ pub struct Unsigned {
     pub relations: Option<Relations>,
 }
 
-impl Unsigned {
+impl MessageLikeUnsigned {
     /// Create a new `Unsigned` with fields set to `None`.
     pub fn new() -> Self {
         Self::default()
@@ -53,6 +54,118 @@ impl Unsigned {
     }
 }
 
+/// Extra information about a state event that is not incorporated into the event's hash.
+#[derive(Clone, Debug, Deserialize, Serialize)]
+#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
+pub struct StateUnsigned<C: EventContent<EventType = StateEventType>> {
+    /// The time in milliseconds that has elapsed since the event was sent.
+    ///
+    /// This field is generated by the local homeserver, and may be incorrect if the local time on
+    /// at least one of the two servers is out of sync, which can cause the age to either be
+    /// negative or greater than it actually is.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub age: Option<Int>,
+
+    /// The client-supplied transaction ID, if the client being given the event is the same one
+    /// which sent it.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub transaction_id: Option<Box<TransactionId>>,
+
+    /// Optional previous content of the event.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub prev_content: Option<C>,
+
+    /// Server-compiled information from other events relating to this event.
+    #[cfg(feature = "unstable-pre-spec")]
+    #[serde(rename = "m.relations", skip_serializing_if = "Option::is_none")]
+    pub relations: Option<Relations>,
+}
+
+impl<C: EventContent<EventType = StateEventType>> StateUnsigned<C> {
+    /// Create a new `Unsigned` with fields set to `None`.
+    pub fn new() -> Self {
+        Self {
+            age: None,
+            transaction_id: None,
+            prev_content: None,
+            #[cfg(feature = "unstable-pre-spec")]
+            relations: None,
+        }
+    }
+
+    /// Whether this unsigned data is empty (all fields are `None`).
+    ///
+    /// This method is used to determine whether to skip serializing the `unsigned` field in room
+    /// events. Do not use it to determine whether an incoming `unsigned` field was present - it
+    /// could still have been present but contained none of the known fields.
+    pub fn is_empty(&self) -> bool {
+        #[cfg(not(feature = "unstable-msc2675"))]
+        {
+            self.age.is_none() && self.transaction_id.is_none() && self.prev_content.is_none()
+        }
+
+        #[cfg(feature = "unstable-msc2675")]
+        {
+            self.age.is_none()
+                && self.transaction_id.is_none()
+                && self.prev_content.is_none()
+                && self.relations.is_none()
+        }
+    }
+}
+
+/// Helper functions for proc-macro code.
+///
+/// Needs to be public for UI tests.
+#[doc(hidden)]
+impl<C: EventContent<EventType = StateEventType>> StateUnsigned<C> {
+    pub fn _from_parts(event_type: &str, object: &RawJsonValue) -> serde_json::Result<Self> {
+        #[derive(Deserialize)]
+        #[serde(bound = "")] // Disable default C: Deserialize bound
+        struct WithRawPrevContent<C> {
+            #[serde(skip_serializing_if = "Option::is_none")]
+            age: Option<Int>,
+            #[serde(skip_serializing_if = "Option::is_none")]
+            transaction_id: Option<Box<TransactionId>>,
+            prev_content: Option<Raw<C>>,
+            #[cfg(feature = "unstable-pre-spec")]
+            #[serde(rename = "m.relations", skip_serializing_if = "Option::is_none")]
+            relations: Option<Relations>,
+        }
+
+        let raw: WithRawPrevContent<C> = from_json_str(object.get())?;
+        let prev_content =
+            raw.prev_content.map(|r| r.deserialize_content(event_type.into())).transpose()?;
+
+        Ok(Self {
+            age: raw.age,
+            transaction_id: raw.transaction_id,
+            #[cfg(feature = "unstable-pre-spec")]
+            relations: raw.relations,
+            prev_content,
+        })
+    }
+
+    pub fn _map_prev_unsigned<T>(&self, f: impl FnOnce(&C) -> T) -> StateUnsigned<T>
+    where
+        T: EventContent<EventType = StateEventType>,
+    {
+        StateUnsigned {
+            age: self.age,
+            transaction_id: self.transaction_id.clone(),
+            prev_content: self.prev_content.as_ref().map(f),
+            #[cfg(feature = "unstable-pre-spec")]
+            relations: self.relations.clone(),
+        }
+    }
+}
+
+impl<C: EventContent<EventType = StateEventType>> Default for StateUnsigned<C> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 /// Extra information about a redacted event that is not incorporated into the event's hash.
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
@@ -82,49 +195,3 @@ impl RedactedUnsigned {
         self.redacted_because.is_none()
     }
 }
-
-#[doc(hidden)]
-#[cfg(feature = "compat")]
-#[derive(Deserialize)]
-pub struct UnsignedWithPrevContent {
-    #[serde(skip_serializing_if = "Option::is_none")]
-    age: Option<Int>,
-
-    #[serde(skip_serializing_if = "Option::is_none")]
-    transaction_id: Option<Box<TransactionId>>,
-
-    #[cfg(feature = "unstable-msc2675")]
-    #[serde(rename = "m.relations", skip_serializing_if = "Option::is_none")]
-    relations: Option<Relations>,
-
-    pub prev_content: Option<Box<serde_json::value::RawValue>>,
-}
-
-#[cfg(feature = "compat")]
-impl From<UnsignedWithPrevContent> for Unsigned {
-    fn from(u: UnsignedWithPrevContent) -> Self {
-        Self {
-            age: u.age,
-            transaction_id: u.transaction_id,
-            #[cfg(feature = "unstable-msc2675")]
-            relations: u.relations,
-        }
-    }
-}
-
-#[doc(hidden)]
-#[cfg(feature = "compat")]
-#[derive(Deserialize)]
-pub struct RedactedUnsignedWithPrevContent {
-    #[serde(skip_serializing_if = "Option::is_none")]
-    redacted_because: Option<Box<SyncRoomRedactionEvent>>,
-
-    pub prev_content: Option<Box<serde_json::value::RawValue>>,
-}
-
-#[cfg(feature = "compat")]
-impl From<RedactedUnsignedWithPrevContent> for RedactedUnsigned {
-    fn from(u: RedactedUnsignedWithPrevContent) -> Self {
-        Self { redacted_because: u.redacted_because }
-    }
-}

crates/ruma-common/tests/events/audio.rs

@@ -15,7 +15,7 @@ use ruma_common::{
             message::{InReplyTo, Relation},
             JsonWebKeyInit,
         },
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     mxc_uri, room_id,
     serde::Base64,
@@ -170,7 +170,7 @@ fn event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/compat.rs

@@ -1,36 +0,0 @@
-#![cfg(feature = "compat")]
-
-use matches::assert_matches;
-use ruma_common::events::room::topic::{RoomTopicEvent, RoomTopicEventContent};
-use serde_json::{from_value as from_json_value, json};
-
-#[test]
-fn deserialize_unsigned_prev_content() {
-    let res = from_json_value::<RoomTopicEvent>(json!({
-        "content": {
-            "topic": "New room topic",
-        },
-        "event_id": "$143273582443PhrSn:example.org",
-        "origin_server_ts": 1_432_735_824_653_u64,
-        "room_id": "!jEsUZKDJdhlrceRyVU:example.org",
-        "sender": "@example:example.org",
-        "state_key": "",
-        "type": "m.room.topic",
-        "unsigned": {
-            "age": 1234,
-            "prev_content": {
-                "topic": "Old room topic",
-            },
-        },
-    }));
-
-    assert_matches!(
-        res,
-        Ok(RoomTopicEvent {
-            content: RoomTopicEventContent { topic: new_topic, .. },
-            prev_content: Some(RoomTopicEventContent { topic: old_topic, .. }),
-            ..
-        }) if new_topic == "New room topic"
-            && old_topic == "Old room topic"
-    );
-}

crates/ruma-common/tests/events/enums.rs

@@ -13,8 +13,8 @@ use ruma_common::{
         AnyEphemeralRoomEvent, AnyMessageLikeEvent, AnyRoomEvent, AnyStateEvent,
         AnyStateEventContent, AnySyncMessageLikeEvent, AnySyncRoomEvent, AnySyncStateEvent,
         EphemeralRoomEventType, GlobalAccountDataEventType, MessageLikeEvent, MessageLikeEventType,
-        RoomAccountDataEventType, StateEvent, StateEventType, SyncMessageLikeEvent, SyncStateEvent,
+        MessageLikeUnsigned, RoomAccountDataEventType, StateEvent, StateEventType,
-        ToDeviceEventType, Unsigned,
+        SyncMessageLikeEvent, SyncStateEvent, ToDeviceEventType,
     },
     MilliSecondsSinceUnixEpoch,
 };
@@ -208,7 +208,7 @@ fn message_event_serialization() {
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(0)),
         room_id: room_id!("!roomid:example.com").to_owned(),
         sender: user_id!("@test:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/file.rs

@@ -12,7 +12,7 @@ use ruma_common::{
             message::{InReplyTo, Relation},
             JsonWebKeyInit,
         },
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     mxc_uri, room_id,
     serde::Base64,
@@ -117,7 +117,7 @@ fn file_event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/image.rs

@@ -16,7 +16,7 @@ use ruma_common::{
             message::{InReplyTo, Relation},
             JsonWebKeyInit,
         },
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     mxc_uri, room_id,
     serde::Base64,
@@ -138,7 +138,7 @@ fn image_event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/location.rs

@@ -12,7 +12,7 @@ use ruma_common::{
         },
         message::MessageContent,
         room::message::{InReplyTo, Relation},
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     room_id, user_id, MilliSecondsSinceUnixEpoch,
 };
@@ -64,7 +64,7 @@ fn event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/message.rs

@@ -10,7 +10,7 @@ use ruma_common::{
         message::MessageEventContent,
         notice::NoticeEventContent,
         room::message::{InReplyTo, Relation},
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     room_id, user_id, MilliSecondsSinceUnixEpoch,
 };
@@ -114,7 +114,7 @@ fn message_event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(
@@ -232,7 +232,7 @@ fn notice_event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(
@@ -299,7 +299,7 @@ fn emote_event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/message_event.rs

@@ -8,7 +8,7 @@ use ruma_common::{
         room::{ImageInfo, ThumbnailInfo},
         sticker::StickerEventContent,
         AnyMessageLikeEvent, AnyMessageLikeEventContent, AnySyncMessageLikeEvent, MessageLikeEvent,
-        MessageLikeEventType, Unsigned,
+        MessageLikeEventType, MessageLikeUnsigned,
     },
     mxc_uri, room_id,
     serde::Raw,
@@ -40,7 +40,7 @@ fn message_serialize_sticker() {
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
         room_id: room_id!("!roomid:room.com").to_owned(),
         sender: user_id!("@carl:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     let actual = to_json_value(&aliases_event).unwrap();

crates/ruma-common/tests/events/mod.rs

@@ -1,7 +1,6 @@
 #![cfg(feature = "events")]
 
 mod audio;
-mod compat;
 mod enums;
 mod ephemeral_event;
 mod event;

crates/ruma-common/tests/events/redacted.rs

@@ -10,9 +10,9 @@ use ruma_common::{
             redaction::{RoomRedactionEventContent, SyncRoomRedactionEvent},
         },
         AnyMessageLikeEvent, AnyRedactedMessageLikeEvent, AnyRedactedSyncMessageLikeEvent,
-        AnyRedactedSyncStateEvent, AnyRoomEvent, AnySyncRoomEvent, EventContent, Redact,
+        AnyRedactedSyncStateEvent, AnyRoomEvent, AnySyncRoomEvent, EventContent,
-        RedactContent, RedactedMessageLikeEvent, RedactedSyncMessageLikeEvent,
+        MessageLikeUnsigned, Redact, RedactContent, RedactedMessageLikeEvent,
-        RedactedSyncStateEvent, RedactedUnsigned, Unsigned,
+        RedactedSyncMessageLikeEvent, RedactedSyncStateEvent, RedactedUnsigned,
     },
     room_id, user_id, MilliSecondsSinceUnixEpoch, RoomVersionId,
 };
@@ -29,7 +29,7 @@ fn unsigned() -> RedactedUnsigned {
         event_id: event_id!("$h29iv0s8:example.com").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
         sender: user_id!("@carl:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     }));
 
     unsigned
@@ -166,7 +166,7 @@ fn redacted_deserialize_any_room_sync() {
         event_id: event_id!("$h29iv0s8:example.com").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
         sender: user_id!("@carl:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     }));
 
     let redacted = json!({
@@ -266,7 +266,7 @@ fn redact_method_properly_redacts() {
         event_id: event_id!("$h29iv0s8:example.com").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
         sender: user_id!("@carl:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     let event: AnyMessageLikeEvent = from_json_value(ev).unwrap();

crates/ruma-common/tests/events/redaction.rs

@@ -4,7 +4,7 @@ use ruma_common::{
     event_id,
     events::{
         room::redaction::{RoomRedactionEvent, RoomRedactionEventContent},
-        AnyMessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeUnsigned,
     },
     room_id, user_id, MilliSecondsSinceUnixEpoch,
 };
@@ -35,7 +35,7 @@ fn serialize_redaction() {
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
         room_id: room_id!("!roomid:room.com").to_owned(),
         sender: user_id!("@carl:example.com").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     let actual = to_json_value(&aliases_event).unwrap();

crates/ruma-common/tests/events/room_message.rs

@@ -11,7 +11,7 @@ use ruma_common::{
             AudioMessageEventContent, InReplyTo, KeyVerificationRequestEventContent, MessageType,
             Relation, RoomMessageEvent, RoomMessageEventContent, TextMessageEventContent,
         },
-        Unsigned,
+        MessageLikeUnsigned,
     },
     mxc_uri, room_id, user_id, DeviceId, MilliSecondsSinceUnixEpoch,
 };
@@ -41,7 +41,7 @@ fn serialization() {
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(10_000)),
         room_id: room_id!("!testroomid:example.org").to_owned(),
         sender: user_id!("@user:example.org").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-common/tests/events/state_event.rs

@@ -1,3 +1,4 @@
+use assign::assign;
 use js_int::{uint, UInt};
 use matches::assert_matches;
 use ruma_common::{
@@ -9,7 +10,7 @@ use ruma_common::{
             ThumbnailInfo,
         },
         AnyRoomEvent, AnyStateEvent, AnyStateEventContent, AnySyncStateEvent, StateEvent,
-        StateEventType, SyncStateEvent, Unsigned,
+        StateEventType, StateUnsigned, SyncStateEvent,
     },
     mxc_uri, room_alias_id, room_id,
     serde::Raw,
@@ -22,17 +23,19 @@ use serde_json::{
 fn aliases_event_with_prev_content() -> JsonValue {
     json!({
         "content": {
-            "aliases": [ "#somewhere:localhost" ]
+            "aliases": ["#somewhere:localhost"],
         },
         "event_id": "$h29iv0s8:example.com",
         "origin_server_ts": 1,
-        "prev_content": {
-            "aliases": [ "#inner:localhost" ]
-        },
         "room_id": "!roomid:room.com",
         "sender": "@carl:example.com",
         "state_key": "",
-        "type": "m.room.aliases"
+        "type": "m.room.aliases",
+        "unsigned": {
+            "prev_content": {
+                "aliases": ["#inner:localhost"],
+            },
+        },
     })
 }
 
@@ -44,13 +47,15 @@ fn serialize_aliases_with_prev_content() {
         ]),
         event_id: event_id!("$h29iv0s8:example.com").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-        prev_content: Some(RoomAliasesEventContent::new(vec![
-            room_alias_id!("#inner:localhost").to_owned()
-        ])),
         room_id: room_id!("!roomid:room.com").to_owned(),
         sender: user_id!("@carl:example.com").to_owned(),
         state_key: "".into(),
-        unsigned: Unsigned::default(),
+        unsigned: assign!(StateUnsigned::default(), {
+            prev_content: Some(RoomAliasesEventContent::new(vec![room_alias_id!(
+                "#inner:localhost"
+            )
+            .to_owned()])),
+        }),
     };
 
     let actual = to_json_value(&aliases_event).unwrap();
@@ -67,11 +72,10 @@ fn serialize_aliases_without_prev_content() {
         ]),
         event_id: event_id!("$h29iv0s8:example.com").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(1)),
-        prev_content: None,
         room_id: room_id!("!roomid:room.com").to_owned(),
         sender: user_id!("@carl:example.com").to_owned(),
         state_key: "".into(),
-        unsigned: Unsigned::default(),
+        unsigned: StateUnsigned::default(),
     };
 
     let actual = to_json_value(&aliases_event).unwrap();
@@ -116,11 +120,13 @@ fn deserialize_aliases_with_prev_content() {
             content,
             event_id,
             origin_server_ts,
-            prev_content: Some(prev_content),
             room_id,
             sender,
             state_key,
-            unsigned,
+            unsigned: StateUnsigned {
+                prev_content: Some(prev_content),
+                ..
+            },
         }) if content.aliases == vec![room_alias_id!("#somewhere:localhost")]
             && event_id == event_id!("$h29iv0s8:example.com")
             && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
@@ -128,7 +134,6 @@ fn deserialize_aliases_with_prev_content() {
             && room_id == room_id!("!roomid:room.com")
             && sender == user_id!("@carl:example.com")
             && state_key.is_empty()
-            && unsigned.is_empty()
     );
 }
 
@@ -144,17 +149,18 @@ fn deserialize_aliases_sync_with_room_id() {
             content,
             event_id,
             origin_server_ts,
-            prev_content: Some(prev_content),
             sender,
             state_key,
-            unsigned,
+            unsigned: StateUnsigned {
+                prev_content: Some(prev_content),
+                ..
+            },
         }) if content.aliases == vec![room_alias_id!("#somewhere:localhost")]
             && event_id == event_id!("$h29iv0s8:example.com")
             && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
             && prev_content.aliases == vec![room_alias_id!("#inner:localhost")]
             && sender == user_id!("@carl:example.com")
             && state_key.is_empty()
-            && unsigned.is_empty()
     );
 }
 
@@ -201,11 +207,10 @@ fn deserialize_avatar_without_prev_content() {
             },
             event_id,
             origin_server_ts,
-            prev_content: None,
             room_id,
             sender,
             state_key,
-            unsigned
+            unsigned,
         }) if event_id == event_id!("$h29iv0s8:example.com")
             && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
             && room_id == room_id!("!roomid:room.com")
@@ -273,7 +278,6 @@ fn deserialize_member_event_with_top_level_membership_field() {
                 content,
                 event_id,
                 origin_server_ts,
-                prev_content: None,
                 sender,
                 ..
             }
@@ -296,16 +300,17 @@ fn deserialize_full_event_convert_to_sync() {
             content,
             event_id,
             origin_server_ts,
-            prev_content: Some(prev_content),
             sender,
             state_key,
-            unsigned,
+            unsigned: StateUnsigned {
+                prev_content: Some(prev_content),
+                ..
+            }
         }) if content.aliases == vec![room_alias_id!("#somewhere:localhost")]
             && event_id == "$h29iv0s8:example.com"
             && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
             && prev_content.aliases == vec![room_alias_id!("#inner:localhost")]
             && sender == "@carl:example.com"
             && state_key.is_empty()
-            && unsigned.is_empty()
     );
 }

crates/ruma-common/tests/events/ui/04-event-sanity-check.rs

@@ -4,7 +4,7 @@
 extern crate serde;
 
 use ruma_common::{
-    events::{EventContent, StateEventType, Unsigned},
+    events::{EventContent, StateEventType, StateUnsigned},
     EventId, MilliSecondsSinceUnixEpoch, RoomId, UserId,
 };
 use ruma_macros::Event;
@@ -18,8 +18,7 @@ pub struct StateEvent<C: EventContent<EventType = StateEventType>> {
     pub origin_server_ts: MilliSecondsSinceUnixEpoch,
     pub room_id: Box<RoomId>,
     pub state_key: String,
-    pub prev_content: Option<C>,
+    pub unsigned: StateUnsigned<C>,
-    pub unsigned: Unsigned,
 }
 
 fn main() {}

crates/ruma-common/tests/events/video.rs

@@ -18,7 +18,7 @@ use ruma_common::{
             JsonWebKeyInit,
         },
         video::{VideoContent, VideoEventContent},
-        AnyMessageLikeEvent, MessageLikeEvent, Unsigned,
+        AnyMessageLikeEvent, MessageLikeEvent, MessageLikeUnsigned,
     },
     mxc_uri, room_id,
     serde::Base64,
@@ -147,7 +147,7 @@ fn event_serialization() {
         sender: user_id!("@user:notareal.hs").to_owned(),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(134_829_848)),
         room_id: room_id!("!roomid:notareal.hs").to_owned(),
-        unsigned: Unsigned::default(),
+        unsigned: MessageLikeUnsigned::default(),
     };
 
     assert_eq!(

crates/ruma-macros/src/events/event.rs

@@ -9,7 +9,7 @@ use syn::{
 
 use super::{
     event_parse::{to_kind_variation, EventKind, EventKindVariation},
-    util::is_non_stripped_room_event,
+    util::{has_prev_content, is_non_stripped_room_event},
 };
 use crate::{import_ruma_common, util::to_camel_case};
 
@@ -135,7 +135,7 @@ fn expand_serialize_event(
 
 fn expand_deserialize_event(
     input: &DeriveInput,
-    _kind: EventKind,
+    kind: EventKind,
     var: EventKindVariation,
     fields: &[Field],
     ruma_common: &TokenStream,
@@ -168,32 +168,14 @@ fn expand_deserialize_event(
         .map(|field| {
             let name = field.ident.as_ref().unwrap();
             let ty = &field.ty;
-            if name == "content" || name == "prev_content" {
+            if name == "content" || (name == "unsigned" && has_prev_content(kind, var)) {
                 if is_generic {
                     quote! { ::std::boxed::Box<#serde_json::value::RawValue> }
                 } else {
                     quote! { #content_type }
                 }
             } else {
-                #[allow(unused_mut)]
+                quote! { #ty }
-                let mut ty = quote! { #ty };
-
-                #[cfg(feature = "compat")]
-                if matches!(_kind, EventKind::State) && name == "unsigned" {
-                    match var {
-                        EventKindVariation::Full | EventKindVariation::Sync => {
-                            ty = quote! { #ruma_common::events::UnsignedWithPrevContent };
-                        }
-                        EventKindVariation::Redacted | EventKindVariation::RedactedSync => {
-                            ty = quote! { #ruma_common::events::RedactedUnsignedWithPrevContent };
-                        }
-                        EventKindVariation::Stripped | EventKindVariation::Initial => {
-                            unreachable!()
-                        }
-                    }
-                }
-
-                ty
             }
         })
         .collect();
@@ -239,45 +221,13 @@ fn expand_deserialize_event(
                         )?;
                     }
                 }
-            } else if name == "prev_content" {
+            } else if name == "unsigned" && has_prev_content(kind, var) {
-                if is_generic {
+                quote! {
-                    #[allow(unused_mut)]
+                    let unsigned = unsigned.map(|json| {
-                    let mut res = quote! {
+                        #ruma_common::events::StateUnsigned::_from_parts(&event_type, &json)
-                        let prev_content = prev_content.map(|json| {
+                            .map_err(A::Error::custom)
-                            C::from_parts(&event_type, &json).map_err(A::Error::custom)
+                    }).transpose()?.unwrap_or_default();
-                        }).transpose()?;
-                    };
-
-                    #[cfg(feature = "compat")]
-                    if let EventKind::State = _kind {
-                        res = quote! {
-                            let prev_content = prev_content
-                                .or_else(|| unsigned.as_mut().and_then(|u| u.prev_content.take()));
-                            #res
-                        };
-                    };
-
-                    res
-                } else {
-                    TokenStream::new()
                 }
-            } else if name == "unsigned" {
-                #[allow(unused_mut)]
-                let mut res = quote! {
-                    let unsigned = unsigned.unwrap_or_default();
-                };
-
-                #[cfg(feature = "compat")]
-                if matches!(_kind, EventKind::State) {
-                    res = quote! {
-                        let unsigned = unsigned.map_or_else(
-                            ::std::default::Default::default,
-                            ::std::convert::From::from,
-                        );
-                    };
-                }
-
-                res
             } else {
                 let attrs: Vec<_> = field
                     .attrs
@@ -296,7 +246,7 @@ fn expand_deserialize_event(
                     )
                 });
 
-                if has_default_attr {
+                if has_default_attr || name == "unsigned" {
                     quote! {
                         let #name = #name.unwrap_or_default();
                     }

crates/ruma-macros/src/events/event_enum.rs

@@ -6,7 +6,7 @@ use syn::{Attribute, Data, DataEnum, DeriveInput, Ident, LitStr};
 
 use super::{
     event_parse::{EventEnumDecl, EventEnumEntry, EventKind, EventKindVariation},
-    util::{has_prev_content_field, EVENT_FIELDS},
+    util::{has_prev_content, is_non_stripped_room_event, EVENT_FIELDS},
 };
 use crate::util::m_prefix_name_to_type_name;
 
@@ -418,18 +418,20 @@ fn expand_accessor_methods(
         let content_enum = kind.to_content_enum();
         let content_variants: Vec<_> = variants.iter().map(|v| v.ctor(&content_enum)).collect();
 
-        let prev_content = has_prev_content_field(kind, var).then(|| {
+        let unsigned = if has_prev_content(kind, var) {
             quote! {
-                /// Returns the previous content for this event.
+                /// Returns this event's unsigned field.
-                pub fn prev_content(&self) -> Option<#content_enum> {
+                pub fn unsigned(&self) -> #ruma_common::events::StateUnsigned<#content_enum> {
                     match self {
                         #(
                             #self_variants(event) => {
-                                event.prev_content.as_ref().map(|c| #content_variants(c.clone()))
+                                event.unsigned._map_prev_unsigned(|c| {
+                                    #content_variants(c.clone())
+                                })
                             },
                         )*
                         Self::_Custom(event) => {
-                            event.prev_content.as_ref().map(|c| #content_enum::_Custom {
+                            event.unsigned._map_prev_unsigned(|c| #content_enum::_Custom {
                                 event_type: crate::PrivOwnedStr(
                                     ::std::convert::From::from(
                                         #ruma_common::events::EventContent::event_type(c).as_str()
@@ -440,7 +442,22 @@ fn expand_accessor_methods(
                     }
                 }
             }
-        });
+        } else if is_non_stripped_room_event(kind, var) {
+            let field_type = field_return_type("unsigned", var, ruma_common);
+            let variants = variants.iter().map(|v| v.match_arm(quote! { Self }));
+
+            quote! {
+                /// Returns this event's unsigned field.
+                pub fn unsigned(&self) -> &#field_type {
+                    match self {
+                        #( #variants(event) => &event.unsigned, )*
+                        Self::_Custom(event) => &event.unsigned,
+                    }
+                }
+            }
+        } else {
+            quote! {}
+        };
 
         quote! {
             /// Returns the content for this event.
@@ -458,7 +475,7 @@ fn expand_accessor_methods(
                 }
             }
 
-            #prev_content
+            #unsigned
         }
     });
 
@@ -558,7 +575,7 @@ fn field_return_type(
             if var.is_redacted() {
                 quote! { #ruma_common::events::RedactedUnsigned }
             } else {
-                quote! { #ruma_common::events::Unsigned }
+                quote! { #ruma_common::events::MessageLikeUnsigned }
             }
         }
         _ => panic!("the `ruma_macros::event_enum::EVENT_FIELD` const was changed"),

crates/ruma-macros/src/events/util.rs

@@ -11,7 +11,7 @@ pub(crate) fn is_non_stripped_room_event(kind: EventKind, var: EventKindVariatio
         )
 }
 
-pub(crate) fn has_prev_content_field(kind: EventKind, var: EventKindVariation) -> bool {
+pub(crate) fn has_prev_content(kind: EventKind, var: EventKindVariation) -> bool {
     matches!(kind, EventKind::State)
         && matches!(var, EventKindVariation::Full | EventKindVariation::Sync)
 }
@@ -34,5 +34,4 @@ pub(crate) const EVENT_FIELDS: &[(&str, EventKindFn)] = &[
             && var != EventKindVariation::Initial
     }),
     ("state_key", |kind, _| matches!(kind, EventKind::State)),
-    ("unsigned", is_non_stripped_room_event),
 ];