private int findLongestNumber(Collection<SourceContextLoader.Line> lines) {
        int maxLineNumber = 1;
        for (SourceContextLoader.Line line : lines) {
            maxLineNumber = line.getLineNumber();
        }
        return String.valueOf(maxLineNumber).length();
    }
Formats source {@link SourceContextLoader.Line} values and writes them to an {@link Appendable}.
smithy-cli/src/main/java/software/amazon/smithy/cli/commands/CodeFormatter.java