Add proper object conversion to deleted diff

Author: mattphillips

src/deleted/index.js

@@ -1,11 +1,14 @@
-import { isEmpty, isObject } from '../utils';
+import { isEmpty, isObject, properObject } from '../utils';
 
 const deletedDiff = (lhs, rhs) => {
   if (lhs === rhs || !isObject(lhs) || !isObject(rhs)) return {};
 
-  return Object.keys(lhs).reduce((acc, key) => {
-    if (rhs.hasOwnProperty(key)) {
-      const difference = deletedDiff(lhs[key], rhs[key]);
+  const l = properObject(lhs);
+  const r = properObject(rhs);
+
+  return Object.keys(l).reduce((acc, key) => {
+    if (r.hasOwnProperty(key)) {
+      const difference = deletedDiff(l[key], r[key]);
 
       if (isObject(difference) && isEmpty(difference)) return acc;
 

src/deleted/index.test.js

@@ -81,5 +81,33 @@ describe('.deletedDiff', () => {
         expect(deletedDiff([new Date('2016')], [])).toEqual({ 0: undefined });
       });
     });
+
+    describe('object create null', () => {
+      test('returns keys as undefined when deleted from right hand side root', () => {
+        const lhs = Object.create(null);
+        const rhs = Object.create(null);
+        lhs.a = 1;
+        lhs.b = 2;
+        rhs.a = 1;
+        expect(deletedDiff(lhs, rhs)).toEqual({ b: undefined });
+      });
+
+      test('returns keys as undefined when deeply deleted from right hand side', () => {
+        const lhs = Object.create(null);
+        const rhs = Object.create(null);
+        lhs.a = { b: 1 };
+        lhs.c = { d: 100 };
+        rhs.a = { b: 1 };
+        rhs.c = {};
+        expect(deletedDiff(lhs, rhs)).toEqual({ c: { d: undefined } });
+      });
+
+      test('returns subset of right hand side with deleted date', () => {
+        const lhs = Object.create(null);
+        const rhs = Object.create(null);
+        lhs.date = new Date('2016');
+        expect(deletedDiff({ date: new Date('2016') }, rhs)).toEqual({ date: undefined });
+      });
+    });
   });
 });