Merge pull request #2039 from modelcontextprotocol/v2/chore/1959-no-floating-promises

chore(lint): enable @typescript-eslint/no-floating-promises in all five ESLint scopes

core/mcp/remote/node/server.ts

@@ -99,6 +99,22 @@ import { ZodError } from "zod";
  */
 const SSE_PRIMING_COMMENT = ":\n\n";
 
+/**
+ * Close an SSE stream from inside an `onAbort` listener, discarding the
+ * rejection.
+ *
+ * `close()` is async and the peer is, by definition, already gone here — a
+ * write that loses the race rejects with nothing left to recover. The listener
+ * itself cannot own the promise either: Hono's `abort()` invokes subscribers
+ * with a bare `subscriber()` (`hono/utils/stream`), so a promise *returned*
+ * from the listener is floated by Hono rather than awaited, turning an
+ * `async` listener into the same unhandled rejection one layer up. Swallowing
+ * it here is the only place the rejection has an owner.
+ */
+export function closeAbortedStream(stream: { close(): Promise<void> }): void {
+  stream.close().catch(() => {});
+}
+
 /**
  * Shape of the initial config returned by GET /api/config (defaults for client).
  */
@@ -854,7 +870,7 @@ export function createRemoteApp(
       stream.onAbort(() => {
         // Client disconnected - clear event consumer
         const shouldCleanup = session.clearEventConsumer();
-        stream.close();
+        closeAbortedStream(stream);
 
         // If transport is dead and no client connected, cleanup session
         if (shouldCleanup || session.isTransportDead()) {
@@ -2460,7 +2476,7 @@ export function createRemoteApp(
       stream.onAbort(() => {
         serverEventSubscribers.delete(send);
         void maybeStopWatcher();
-        stream.close();
+        closeAbortedStream(stream);
       });
 
       // Hono closes the stream the moment this callback returns, so hold the