Pressing "delete" (non-Mac) sends EOF to init questionnaire.

[GrooveStomp]

On a non-Mac computer, pressing the delete key results in an EOF being sent to the zero init questionnaire prompt:

✔ Production Frontend Host Name (e.g. app.): app-20-09-14.█
ERROR[2020-09-14T09:46:22-07:00] ❗  Exiting prompt:  EOF

[GrooveStomp]

I started looking into this a bit. We use github.com/manifoldco/promptui; but I'm not sure if the bug lies in that library, or in the readline library it uses: github.com/chzyer/readline.

[GrooveStomp]

Sorry, I need to clarify that a bit. There is a bug in zero where we interpret a delete as EOF. This specific bug doesn't occur in promptui. Here's a small demo:

package main

import (
	"fmt"
	"github.com/manifoldco/promptui"
)

func main() {
	prompt := promptui.Prompt{
		Label:    "String",
		Validate: nil,
	}

	result, _ := prompt.Run()

	fmt.Printf("Result: %q\n", result)
}

And here's the session where I type fooo, then left-arrow twice, then delete:

↳ go run main.go
✔ String: fo█o
Result: ""

So there appears to be a bug in promptui; although it manifests differently than it does in zero.

[GrooveStomp]

I'm able to reproduce this with Readline like so:

package main

import (
	"fmt"
	"github.com/chzyer/readline"
	"github.com/manifoldco/promptui"
	"os"
)

func main() {
	c := &readline.Config{
		HistoryLimit:   -1,
		UniqueEditLine: true,
	}

	err := c.Init()
	if err != nil {
		panic(err)
	}

	rl, err := readline.NewEx(c)
	if err != nil {
		panic(err)
	}

	prompt := promptui.Prompt{
		Label:     "Text entry",
		Default:   "Delete me",
		AllowEdit: true,
	}

	for {
		_, err := rl.Readline()
		if err != nil {
			fmt.Printf("Error in readline: %v\n", err)
			os.Exit(1)
			break
		}
	}

	fmt.Print("Good!")
	os.Exit(0)
}

And then running the program, deleting all text at the prompt and pressing ctrl+D or delete:

↳ ./promptui-test
Error in readline: EOF