My first answer is "I don't know"; there are two factors involved:

* Some languages have support for using both `\n` and `\r` as a newline. Python, Java and PHP are some of those. We're at risk of counting lines twice.
* Because the parsing is done within a pygments `Formatter`, it's possible that I'm just looking at a token where it's already converted to `\n` for me?

I'll make a test file and see what I come up with.