You there are already dozens of modules that do this, right? Yours seems to only parse single lines, not the context.
Anyway, that's a nice beggining.
I actually added support for a whole markdown file, thank you for pointing this out to me.
I'd recommend that you add a .gitignore line for the node_modules folder, which will reduce the size of the git project by a lot
the build for codecov didn't work when I did that.
I'm not too familiar with travis/codecov, but maybe you could add "npm install" to your .travis.yml "install" section? That way the dependencies would be downloaded before the scripts ran.