refactor: Add function to state_accessor to get create event

src/service/rooms/event_handler/handle_incoming_pdu.rs

@@ -209,11 +209,11 @@ pub async fn handle_incoming_pdu<'a>(
 	}
 
 	// Fetch create event
-	let create_event = &(self
+	let ref create_event = self
 		.services
 		.state_accessor
-		.room_state_get(room_id, &StateEventType::RoomCreate, "")
-		.await?);
+		.get_room_create_event(room_id)
+		.await;
 
 	let (incoming_pdu, val) = self
 		.handle_outlier_pdu(origin, create_event, event_id, room_id, value, false)

src/service/rooms/state_accessor/mod.rs

@@ -6,7 +6,7 @@ mod user_can;
 use std::{collections::HashSet, sync::Arc};
 
 use async_trait::async_trait;
-use conduwuit::{Event, Result, err};
+use conduwuit::{Event, Pdu, Result, err};
 use database::Map;
 use ruma::{
 	EventEncryptionAlgorithm, JsOption, OwnedRoomAliasId, OwnedUserId, RoomId, UserId,
@@ -164,6 +164,13 @@ impl Service {
 			.is_ok()
 	}
 
+	/// Get a room's create event.
+	pub async fn get_room_create_event(&self, room_id: &RoomId) -> Pdu {
+		self.room_state_get(room_id, &StateEventType::RoomCreate, "")
+			.await
+			.expect("room should have a create event")
+	}
+
 	/// Get a set of the room's creators. This will always contain a single user
 	/// for room versions 11 and earlier.
 	pub async fn get_room_creators(&self, room_id: &RoomId) -> HashSet<OwnedUserId> {
@@ -176,10 +183,8 @@ impl Service {
 			.rules()
 			.expect("room version should be known");
 
-		let create_event = self
-			.room_state_get(room_id, &StateEventType::RoomCreate, "")
-			.await
-			.expect("room should have a create event");
+		let create_event = self.get_room_create_event(room_id).await;
+
 		let create_content: RoomCreateEventContent = create_event
 			.get_content()
 			.expect("create event content should be valid");

src/service/rooms/state_accessor/user_can.rs

@@ -44,31 +44,6 @@ pub async fn user_can_redact(
 		)));
 	}
 
-	let create_event = self
-		.room_state_get(room_id, &StateEventType::RoomCreate, "")
-		.await?;
-	let create_event_content: RoomCreateEventContent = create_event.get_content().unwrap();
-	let room_version_rules = create_event_content
-		.room_version
-		.rules()
-		.expect("room version should have defined rules");
-	if room_version_rules
-		.authorization
-		.explicitly_privilege_room_creators
-	{
-		let sender_owned = sender.to_owned();
-		// NOTE: we don't check the pre-v11 `creator` field because no room version has
-		// `explicitly_privilege_room_creators` and `use_room_create_sender` set at the
-		// same time
-		if sender == create_event.sender()
-			|| create_event_content
-				.additional_creators
-				.contains(&sender_owned)
-		{
-			return Ok(true);
-		}
-	}
-
 	let power_levels = self.get_room_power_levels(room_id).await;
 
 	if power_levels.user_can_redact_event_of_other(sender) {