[Bug]: Unhandled exception get logged with a very weird format

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winston exceptions, unhandled exceptions, winston weird exception log etc.

The problem

I'm using winston to log everything in my NestJS app and it works perfectly except for one problem: When an unhandled exception occurs (for example if I throw one on purpose) and passed onto node, winston logs it but in a very weird format:

{"date":"Mon Sep 04 2023 18:59:25 GMT+0300 (שעון ישראל (קיץ))","error":{},"exception":true,"level":"error","message":"unhandledRejection: djdjd\nError: djdjd\n    at bootstrap (file:///C:/proj/integration/test/src/main.ts:17:9)\n    at file:///C:/proj/integration/test/src/main.ts:23:1\n    at ModuleJob.run (node:internal/modules/esm/module_job:194:25)","os":{"loadavg":[0,0,0],"uptime":377372.531},"process":{"argv":["C:\\Program Files\\nodejs\\node.exe","C:\\proj\\integration\\test\\dist\\main"],"cwd":"C:\\proj\\integration\\test","execPath":"C:\\Program Files\\nodejs\\node.exe","gid":null,"memoryUsage":{"arrayBuffers":503050,"external":2631243,"heapTotal":40247296,"heapUsed":27436640,"rss":82460672},"pid":18272,"uid":null,"version":"v18.16.1"},"stack":"Error: djdjd\n    at bootstrap (file:///C:/proj/integration/test/src/main.ts:17:9)\n    at file:///C:/proj/integration/test/src/main.ts:23:1\n    at ModuleJob.run (node:internal/modules/esm/module_job:194:25)","trace":[{"column":9,"file":"file:///C:/proj/integration/test/src/main.ts","function":"bootstrap","line":17,"method":null,"native":false},{"column":1,"file":"file:///C:/proj/integration/test/src/main.ts","function":null,"line":23,"method":null,"native":false},{"column":25,"file":"node:internal/modules/esm/module_job","function":"ModuleJob.run","line":194,"method":"run","native":false}]}

Sometimes it even logs the same thing 2 or even 3 times in a row. For the life of me I can't figure out how to format this any differently or at least take off some (most) of the properties there are here. This is my logger config:

    // Define the levels that can be used for logging
    const levels = {
      error: 0,
      warn: 1,
      info: 2,
      debug: 3,
    };
    const maxLevelToLog = process.env.NODE_ENV === 'dev' ? 'debug' : 'info';
    const customFormat = winstonFormat.printf(({ level, message, exception }) => {
      return `${level}: ${message}${exception ? '\n' + exception.stack : ''}`;
    });
    const format = winstonFormat.combine(winstonFormat.timestamp(), winstonFormat.json());

    // Tell winston to log to console, file and datadog
    const customTransports = [
      new transports.Console({ format }),
      new transports.DailyRotateFile({
        frequency: '24h',
        datePattern: 'YYYY-MM-DD',
        dirname: logsFolderName,
        extension: '.log',
        filename: logsFileNameFormat,
        handleExceptions: true,
        maxSize: '5m',
        maxFiles: '30d',
        format,
      }),
    ];

    return {
      level: maxLevelToLog,
      levels,
      transports: customTransports,
      exceptionHandlers: new transports.Console({format: customFormat}),
    };

What version of Winston presents the issue?

v3.10.0

What version of Node are you using?

v18.16.1

If this worked in a previous version of Winston, which was it?

No response

Minimum Working Example

No response

Additional information

No response

winstonjs / winston