I also wonder if NonTTY can have a better name 🤔

Why don't you keep a single error handler and check if it's a TTY in the handler?

that would be ideal, but would also require a breaking change, as currently the error handler expects the styles etc

that would be ideal, but would also require a breaking change, as currently the error handler expects the styles etc

if noTTY { fmt.Fprint(w, noStyles) }, no?

What's the best way to test this one?

Also I'd probably call NonTTY NoTTY (if I'm understanding the use correctly) as NoTTY is more consistent with naming in our other projects.

@meowgorithm you can add a no tty error handler to example/main.go:

		fang.WithNoTTYErrorHandler(func(w io.Writer, err error) {
			fmt.Fprintf(w, "Custom no-TTY error: %v\n", err)
		}),

And then run it like:

go run ./example/main.go nopenopenope 2>&1 | cat

that would be ideal, but would also require a breaking change, as currently the error handler expects the styles etc

if noTTY { fmt.Fprint(w, noStyles) }, no?

no... the err handler expects the styles.

no... the err handler expects the styles.

Right, but can't we do something like this?

func DefaultErrorHandler(w io.Writer, styles Styles, err error) {
	if f, ok := w.(term.File); !ok || !term.IsTerminal(f.Fd()) {
		_, _ = fmt.Fprintln(w, err.Error())
		return
	}

	_, _ = fmt.Fprintln(w, styles.ErrorHeader.String())
	_, _ = fmt.Fprintln(w, styles.ErrorText.Render(err.Error()+"."))
	_, _ = fmt.Fprintln(w)
	if isUsageError(err) {
		_, _ = fmt.Fprintln(w, lipgloss.JoinHorizontal(
			lipgloss.Left,
			styles.ErrorText.UnsetWidth().Render("Try"),
			styles.Program.Flag.Render(" --help "),
			styles.ErrorText.UnsetWidth().UnsetMargins().UnsetTransform().Render("for usage."),
		))
		_, _ = fmt.Fprintln(w)
	}
}

there's still the issue of that the user might want to do something different if output is not a tty (like we do by default in fang).
This way gives the most flexibility to the caller IMHO.

btw your suggestion is similar to my initial implementation, check PR description

although, triple checking now, maybe the bg color thing isn't a problem as that check is also guarded by a if isTerm 🤔

@aymanbagabas you are absolutely right!

If we're breaking the API, I would query the terminal and check IsTTY for each FD, stdin, out, and err, then store them in the context and pass the context down to handlers etc. This way you don't need to perform the checks multiple times and you only query once.

If we're breaking the API, I would query the terminal and check IsTTY for each FD, stdin, out, and err, then store them in the context and pass the context down to handlers etc. This way you don't need to perform the checks multiple times and you only query once.

not doing it, ended up going back to my og fix (which was also suggested by you), as it works well enough.