improve coverage

Fixes #333 
It's not a pretty diff, but it will put us back in the green.

![screen shot 2014-12-16 at 4 46 17 pm](https://cloud.githubusercontent.com/assets/723048/5462555/146e4368-8543-11e4-8f7a-3c5767622209.png)

I usually just use a short name for instances like `trans` but that might not be descriptive enough. I'd suggest longer `aTransaction` or `theTransaction`. Exact words with differing capitalisation just scares me.