clippy: add must_use attribute

src/service/server_keys/mod.rs

@@ -62,14 +62,17 @@ impl crate::Service for Service {
 
 #[implement(Service)]
 #[inline]
+#[must_use]
 pub fn keypair(&self) -> &Ed25519KeyPair { &self.keypair }
 
 #[implement(Service)]
 #[inline]
+#[must_use]
 pub fn active_key_id(&self) -> &ServerSigningKeyId { self.active_verify_key().0 }
 
 #[implement(Service)]
 #[inline]
+#[must_use]
 pub fn active_verify_key(&self) -> (&ServerSigningKeyId, &VerifyKey) {
 	debug_assert!(self.verify_keys.len() <= 1, "more than one active verify_key");
 	self.verify_keys

src/service/users/mod.rs

@@ -313,6 +313,7 @@ impl Service {
 	}
 
 	/// Creates a new sync filter. Returns the filter id.
+	#[must_use]
 	pub fn create_filter(&self, user_id: &UserId, filter: &FilterDefinition) -> String {
 		let filter_id = utils::random_string(4);
 
@@ -388,6 +389,7 @@ impl Service {
 
 	/// Creates a short-lived login token, which can be used to log in using the
 	/// `m.login.token` mechanism.
+	#[must_use]
 	pub fn create_login_token(&self, user_id: &UserId, token: &str) -> u64 {
 		use std::num::Saturating as Sat;