fstream-npm
This is an fstream DirReader class that will read a directory and filter things according to the semantics of what goes in an npm package.
For example:
// This will print out all the files that would be included
// by 'npm publish' or 'npm install' of this directory.
var FN = require("fstream-npm")
FN({ path: "./" })
.on("child", function (e) {
console.error(e.path.substr(e.root.path.length + 1))
})