Function StripANSI

pkg/stringutil/ansi.go:18–44

StripANSI removes ANSI escape codes from a string using a comprehensive byte scanner. It handles CSI sequences (\x1b[), OSC sequences (\x1b]), G0/G1 character set selections, keypad mode sequences, reset sequences, and other common 2-character escape sequences. This is more thorough than regex-base

(s string)

// This is more thorough than regex-based approaches and correctly handles edge cases
// such as incomplete sequences, nested sequences, and non-standard terminal sequences.
func StripANSI(s string) string {
	if s == "" {
		return s
	}

	ansiLog.Printf("StripANSI: input length=%d", len(s))

	var result strings.Builder
	result.Grow(len(s)) // Pre-allocate capacity for efficiency

	i := 0
	for i < len(s) {
		if s[i] != '\x1b' {
			result.WriteByte(s[i])
			i++
			continue
		}
		if i+1 >= len(s) {
			i++ // ESC at end of string, skip it
			continue
		}
		// Found ESC character, advance past the sequence
		i = skipEscapeSequence(s, i)
	}

	return result.String()
}

// skipEscapeSequence advances past a complete ANSI escape sequence starting at i.
// i must point at '\x1b' and i+1 must be within the string.