`require.cache` is listed [in the API docs](http://nodejs.org/docs/latest/api/globals.html#globals_require_cache) and there are no warnings of deprecation (unlike `extensions`). I'm guessing that's because of this use case. Modules with internal state need testing too!

What do you mean by travis magic here? This is being tested on 0.8, 0.10 and 0.11. Do you mean sniffing for `require.cache`?