CTRL+C sets value to currently selected option in Select

[chrishessler]

When presenting the user with a Select form, I would expect, for example a var choiceId int to be 0. Instead it sets the value to the currently selected/hovered option.

My program continues execution after pressing CTRL+C with said value resulting in (imo) unexpected behaviour because of this.

func ChoiceInteractive(targets string) error {
	var choiceId int
	form := huh.NewForm(
		huh.NewGroup(
			huh.NewSelect[int]().
				Title("Make a choice").
				Options(
					huh.NewOption("A", 1),
					huh.NewOption("B", 2),
					huh.NewOption("C", 3),
					huh.NewOption("D", 4),
				).
				Value(&choiceId),
		),
	).WithTheme(huh.ThemeBase16())

	form.Run()

	// ...executed code I wish not to be executed after pressing CTRL+C
}

Is this a bug? If not, how should I correctly end execution when CTRL+C is pressed?

[hxlnt]

You can do something like this:

err := huh.NewForm(
	huh.NewGroup(
		huh.NewSelect[int]().
			Title("Make a choice").
			Options(
				huh.NewOption("A", 1),
				huh.NewOption("B", 2),
				huh.NewOption("C", 3),
				huh.NewOption("D", 4),
			).
			Value(&choiceId),
	),
).WithTheme(huh.ThemeBase16()).Run()
if err != nil {
    // Catch Ctrl-C here, return or whatever so that it doesn't fall through
}
// Code that you only want to run if Ctrl-C didn't happen

[chrishessler]

Unfortunately that doesn't work. CTRL+C doesn't seem to result in an error being returned.

[hxlnt]

Do you mean the code inside if err != nil { ... } isn't executed when Ctrl-C is pressed? An error won't be shown unless you explicitly print it to the terminal. In this case, it's just helpful to use the returned err to elicit different behavior. Also, in that branch of the logic, you'll need to set your value to whatever "nothing" means to you (0, nil, "", etc.).

I tried this minimal repro code, and it worked for me (huh v0.7.0). Hope this is helpful.

package main

import (
	"fmt"
	"os"

	"github.com/charmbracelet/huh"
)

func main() {
	var choiceId int
	err := huh.NewForm(
		huh.NewGroup(
			huh.NewSelect[int]().
				Title("Make a choice").
				Options(
					huh.NewOption("A", 1),
					huh.NewOption("B", 2),
					huh.NewOption("C", 3),
					huh.NewOption("D", 4),
				).
				Value(&choiceId),
		),
	).WithTheme(huh.ThemeBase16()).Run()
	if err != nil {
		fmt.Println("You pressed Ctrl-C. I'll explicitly set choiceId=0.")
		choiceId = 0
	} else {
		fmt.Println("You did not press Ctrl-C.")
	}
	fmt.Println("choiceId: ", choiceId)
	os.Exit(0)
}

[SavSanta]

@hxlnt. I was just about to open a new discussion on how to catch OS signals. I only needed Ctrl+C specifically so this actually helped in that regard and I can just match on the errmsg.

err := form.Run()
	if err != nil {
		if err.Error() == "user aborted" {
			fmt.Println("Cancelled...")
			os.Exit(1)
		}
	}

Thanks!

Edit: Afetr Rachel's answer coincidntwlly this came up on the golang sub. It ess pointed out that there is a type for it to compare agaisnt using err.Is as so:

if err != nil && errors.Is(err, huh.ErrUserAborted) {
    fmt.Println("Cancelled...")
    os.Exit(1)
}

Then i realized since the doc/source didnt define many types and i only care about Ctrl+C we can reduce it to just

err := form.Run()
	if errors.Is(err, huh.ErrUserAborted) {
	    fmt.Println("Cancelled...")
	    os.Exit(1)
	}