Formatter Concatenates Messages in logger.info('message1', {message: 'message2'})

[mountHouli]

Please tell us about your environment:

• winston version?
  • winston@2
  • winston@3 Specifically, I'm using winston 3.2.1 because I wanted these fixes: Better handling of new Error(string) throughout the pipeline(s). Fixes #1338, #1486 #1562
• node -v outputs: v8.15.0
• Operating System? macOS
• Language? Vanilla JS in Node v8.15.0

What is the problem?

In the callback of the printf formatter below, in the info object, the value of info.message is my "log message" (see below) and "object message" (or "error message" as in the 2nd case) concatenated directly together (e.g. log messageobject message).

const winston = require('winston')
const { format, createLogger, transports } = winston

const formatter = format.printf(info => {
  return `The log message and the object message (or error message) are unfortuantely concatenated directly together without a space and/or colon+space in between: ${info.message}`
});

const logger = createLogger({
  level: 'debug',
  format: formatter,
  transports: [
    new transports.Console(),
  ],
})

// Case 1
logger.info('log message', { message: 'object message' });
// Case 2
logger.info('log message', new Error('error message'));

What do you expect to happen instead?

Depends on what the community thinks. Here are some options for the value of info.message:

1. "log message: object message"
2. "log message object message"
3. "log message"

I like option 1, but I recognize this is a bit fancy and might catch users of this library by surprise.

Other information

I also tested and found this same type of issue occurring with the following formatters:
json,logstash, printf, prettyPrint, simple. I did not test any other formatters (I don't know if other formatters even exist).

Lastly, I recognize that this might be an issue not with winstonjs/winston but actually an issue with winstonjs/logform. If that is the case, I apologize. I took a brief look at the code today to figure out in which would be the correct repo to post this issue, but I could not make a determination. If someone says this is an issue with a different repo (e.g. winstonjs/logform) just LMK and I'll close this issue here and move it to the appropriate repo.

[DABH]

Going to fix this via #1740 but if people would prefer another solution please do speak up. Thanks!

[mountHouli]

Thanks!