Multiline rendering bug

[liamg]

I'm using multiline rendering via AcceptMultiline, and while the input is correctly received, when I input multiple lines, the lines aren't rendered properly once I input more than two lines.

The issue can be reproduced with this minimal example:

package main

import (
	"strings"

	"github.com/reeflective/readline"
)

func main() {
	bashMultiline := func(line []rune) (accept bool) {
		if strings.HasSuffix(string(line), "\\") {
			return false
		}

		return true
	}
	
	shell := readline.NewShell()
	shell.AcceptMultiline = bashMultiline

	shell.Readline()
}

Keep hitting backslash and enter and you'll see some weird rendering issues.