fix: add tests, missing feature gates, small test issues

Author: erenatas

crates/rmcp/src/transport/common/http_header.rs

@@ -65,8 +65,10 @@ pub(crate) fn extract_scope_from_header(header: &str) -> Option<String> {
 
 #[cfg(test)]
 mod tests {
+    #[cfg(feature = "client-side-sse")]
     use super::*;
 
+    #[cfg(feature = "client-side-sse")]
     #[test]
     fn extract_scope_quoted() {
         let header = r#"Bearer error="insufficient_scope", scope="files:read files:write""#;
@@ -76,6 +78,7 @@ mod tests {
         );
     }
 
+    #[cfg(feature = "client-side-sse")]
     #[test]
     fn extract_scope_unquoted() {
         let header = r#"Bearer scope=read:data, error="insufficient_scope""#;
@@ -85,12 +88,14 @@ mod tests {
         );
     }
 
+    #[cfg(feature = "client-side-sse")]
     #[test]
     fn extract_scope_missing() {
         let header = r#"Bearer error="invalid_token""#;
         assert_eq!(extract_scope_from_header(header), None);
     }
 
+    #[cfg(feature = "client-side-sse")]
     #[test]
     fn extract_scope_empty_header() {
         assert_eq!(extract_scope_from_header("Bearer"), None);

crates/rmcp/src/transport/common/server_side_http.rs

@@ -81,6 +81,15 @@ impl ServerSseMessage {
         }
     }
 
+    /// Wrap a JSON-RPC message without an event ID or retry hint.
+    pub fn from_message(message: ServerJsonRpcMessage) -> Self {
+        Self {
+            event_id: None,
+            message: Some(Arc::new(message)),
+            retry: None,
+        }
+    }
+
     /// Create a priming event that tells the client to reconnect after `retry`
     /// if the connection drops.
     /// See [SEP-1699](https://github.com/modelcontextprotocol/modelcontextprotocol/issues/1699).
@@ -191,3 +200,49 @@ where
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::model::{EmptyResult, JsonRpcResponse, JsonRpcVersion2_0, RequestId, ServerResult};
+
+    fn dummy_message() -> ServerJsonRpcMessage {
+        ServerJsonRpcMessage::Response(JsonRpcResponse {
+            jsonrpc: JsonRpcVersion2_0,
+            id: RequestId::Number(1),
+            result: ServerResult::EmptyResult(EmptyResult {}),
+        })
+    }
+
+    #[test]
+    fn default_has_all_none() {
+        let msg = ServerSseMessage::default();
+        assert!(msg.event_id.is_none());
+        assert!(msg.message.is_none());
+        assert!(msg.retry.is_none());
+    }
+
+    #[test]
+    fn new_sets_event_id_and_message() {
+        let msg = ServerSseMessage::new("42", dummy_message());
+        assert_eq!(msg.event_id.as_deref(), Some("42"));
+        assert!(msg.message.is_some());
+        assert!(msg.retry.is_none());
+    }
+
+    #[test]
+    fn from_message_has_no_event_id() {
+        let msg = ServerSseMessage::from_message(dummy_message());
+        assert!(msg.event_id.is_none());
+        assert!(msg.message.is_some());
+        assert!(msg.retry.is_none());
+    }
+
+    #[test]
+    fn priming_sets_event_id_and_retry() {
+        let msg = ServerSseMessage::priming("0", Duration::from_secs(5));
+        assert_eq!(msg.event_id.as_deref(), Some("0"));
+        assert!(msg.message.is_none());
+        assert_eq!(msg.retry, Some(Duration::from_secs(5)));
+    }
+}

crates/rmcp/src/transport/streamable_http_server/tower.rs

@@ -679,11 +679,8 @@ where
                     .initialize_session(&session_id, message)
                     .await
                     .map_err(internal_error_response("create stream"))?;
-                let stream = futures::stream::once(async move {
-                    let mut msg = ServerSseMessage::default();
-                    msg.message = Some(Arc::new(response));
-                    msg
-                });
+                let stream =
+                    futures::stream::once(async move { ServerSseMessage::from_message(response) });
                 // Prepend priming event if sse_retry configured
                 let stream = if let Some(retry) = self.config.sse_retry {
                     let priming = ServerSseMessage::priming("0", retry);
@@ -760,9 +757,7 @@ where
                         // SSE mode (default): original behaviour preserved unchanged
                         let stream = ReceiverStream::new(receiver).map(|message| {
                             tracing::trace!(?message);
-                            let mut msg = ServerSseMessage::default();
-                            msg.message = Some(Arc::new(message));
-                            msg
+                            ServerSseMessage::from_message(message)
                         });
                         Ok(sse_stream_response(
                             stream,

crates/rmcp/tests/test_inflight_response_drain.rs

@@ -1,4 +1,4 @@
-#![cfg(not(feature = "local"))]
+#![cfg(all(feature = "client", feature = "server", not(feature = "local")))]
 // cargo test --test test_inflight_response_drain --features "client server"
 
 use std::{