// Phase 256 P0: Minimal split test fixture
// Tests: split("a,b,c", ",") → ["a","b","c"] → length = 3

static box StringUtils {
    split(s, separator) {
        local result = new ArrayBox()
        if separator.length() == 0 {
            result.push(s)
            return result
        }

        local start = 0
        local i = 0
        loop(i <= s.length() - separator.length()) {
            if s.substring(i, i + separator.length()) == separator {
                result.push(s.substring(start, i))
                start = i + separator.length()
                i = start
            } else {
                i = i + 1
            }
        }

        if start <= s.length() {
            result.push(s.substring(start, s.length()))
        }

        return result
    }
}

static box Main {
    main() {
        local result = StringUtils.split("a,b,c", ",")
        return result.length()
    }
}