Output colored red in callr::r()

[pwseo]

When using cli:: functions inside a callr::r invocation, output is always colored red (first noticed this using W Landau's targets package).
I'm not really sure this is even cli's fault, but I'm not experienced enought to debug this on my own.

Here's a screenshot of the problem:

[gaborcsardi]

cli uses message() which outputs to the standard error, and RStudio colours the standard error red.

When not using callr, cli figures out that it is in RStudio, so it outputs to the standard output to avoid this. But in the callr subprocess we have no way to tell if the output will be eventually in RStudio or not, so we cannot do that.

So there is not much we can do about this, apart from hoping that the red default will change.

[pwseo]

Oh, I see. Thank you for the clarification. I have a follow-up question though: Is there a way to configure cli to use stdout instead of stderr, then?

[gaborcsardi]

cli uses base::message() for its messages. I don't know if it is possible to make message() print to stdout.

[wlandau]

cli uses message() which outputs to the standard error, and RStudio colours the standard error red.

I also see the red text executing callr::r(\() cli::cli_text("abc"), show = TRUE) in an R process launched in a regular terminal outside the RStudio IDE. Am I missing something?

[wlandau]

I can remove the red if I redirect stderr to stdout, but I lose other colors as well. In the reprex below, I expect the check mark to be green, but it is white (both in the terminal and in RStudio Desktop.) How do I preserve the colors I would see outside the callr process? options(cli.color = TRUE) does not seem to work on my end.

tmp <- callr::r(
  \() {
    options(cli.color = TRUE)
    cli::cli_alert_success('abc')
  },
  show = TRUE,
  stderr = "2>&1"
)

✔ abc

I am using cli 3.6.2 and callr 3.7.3