ran npm run tdd

test/averageBy/averageBy.js

@@ -1,3 +1,4 @@
-module.exports = averageBy = (arr, fn) =>
+const averageBy = (arr, fn) =>
 arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val) => acc + val, 0) /
-arr.length;
+arr.length;
+ module.exports = averageBy