Remove map and reduce for a single reduce

Author: mattphillips

src/index.js

@@ -5,15 +5,15 @@ const diff = (lhs, rhs) => {
 
   if (typeof rhs !== 'object' || rhs === null) return rhs;
 
-  return Object.keys(rhs).map(key => {
-    if (!lhs.hasOwnProperty(key)) return { [key]: rhs[key] };
+  return Object.keys(rhs).reduce((acc, key) => {
+    if (!lhs.hasOwnProperty(key)) return { ...acc, [key]: rhs[key] };
 
     const lhsValue = lhs[key];
     const rhsValue = rhs[key];
-    if (isEqual(lhsValue, rhsValue)) return {};
+    if (isEqual(lhsValue, rhsValue)) return acc;
 
-    return { [key]: diff(lhsValue, rhsValue) };
-  }).reduce((acc, next) => ({ ...acc, ...next }), {});
+    return { ...acc, [key]: diff(lhsValue, rhsValue) };
+  }, {});
 };
 
 export default diff;