[release/8.0] Handle rejected promises inside incoming Invocation messages

src/SignalR/clients/ts/signalr/src/HubConnection.ts

@@ -614,8 +614,10 @@ export class HubConnection {
 
                 switch (message.type) {
                     case MessageType.Invocation:
-                        // eslint-disable-next-line @typescript-eslint/no-floating-promises
-                        this._invokeClientMethod(message);
+                        this._invokeClientMethod(message)
+                            .catch((e) => {
+                                this._logger.log(LogLevel.Error, `Invoke client method threw error: ${getErrorString(e)}`)
+                            });
                         break;
                     case MessageType.StreamItem:
                     case MessageType.Completion: {

src/SignalR/clients/ts/signalr/tests/HubConnection.test.ts

@@ -818,6 +818,38 @@ describe("HubConnection", () => {
             });
         });
 
+        it("callback invoked when server invokes a method on the client and then handles rejected promise on send", async () => {
+            await VerifyLogger.run(async (logger) => {
+                const connection = new TestConnection();
+                const hubConnection = createHubConnection(connection, logger);
+                let promiseRejected = false;
+                try {
+                    await hubConnection.start();
+                    const p = new PromiseSource<void>();
+                    hubConnection.on("message", async () => {
+                        // Force sending of response to error
+                        connection.send = () => {
+                            promiseRejected = true;
+                            return Promise.reject(new Error("Send error"));
+                        }
+                        p.resolve();
+                    });
+                    connection.receive({
+                        arguments: ["test"],
+                        nonblocking: true,
+                        target: "message",
+                        invocationId: "0",
+                        type: MessageType.Invocation,
+                    });
+
+                    await p;
+                    expect(promiseRejected).toBe(true);
+                } finally {
+                    await hubConnection.stop();
+                }
+            }, new RegExp("Invoke client method threw error: Error: Send error"));
+        });
+
         it("stop on handshake error", async () => {
             await VerifyLogger.run(async (logger) => {
                 const connection = new TestConnection(false);