.gitignore

.DS_Store
node_modules

bar.js

function thing(thing) {}

export default thing;

build.js

'use strict';

function thing(thing) {}

var bar = _thing;

function thing(thing) {}

var foo = thing;

exports.foo = foo;
exports.bar = bar;

foo.js

function thing(thing) {}

export default thing;

index.js

import foo from "./foo";
import bar from "./bar";

export {
  foo,
  bar
};

package.json

{
  "main": "build",
  "scripts": {
    "pretest": "rollup --format=cjs -- index.js > build.js",
    "test": "node -e 'require(\"./\")'"
  },
  "devDependencies": {
    "rollup": "^0.8.1"
  }
}