ANSI Escape Codes colors and print length

Getting Help
1

I have a string with ansi escape codes in it to print some things in color as well as some runes. I already know to convert the string to a slice of runes to see how many codepoints there are (and give me the print length of the string in characters) but Now I need to know how long it is without the escape character to give me the true print length.

I thought I was close when I found ansi package - github.com/jcorbin/anansi/ansi - Go Packages but I do not see the answer to my issue.

Any help would be appreciated.

2

If the only ansi escape sequences in the string are for SGRs, then it can be quite simple. Such sequences start with “ESC[” and end with “m”.

So this would be a crude way to count the non-escape runes.

package main

import "fmt"

func main() {
	escaped := "\x1b[1;31mred\x1b[0m\x1b[1;32mgreen\x1b[0m"

	withinEscapeSequence := false
	runeCount := 0
	for _, r := range escaped {
		if withinEscapeSequence {
			if r == 'm' {
				withinEscapeSequence = false
			}
		} else {
			if r == '\x1b' {
				withinEscapeSequence = true
			} else {
				runeCount++
			}
		}
	}

	fmt.Println(runeCount)
}

playground

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