Fix restore method to work with nested keys (#160)

* Fix restore method to work with nested changes object

* Insert missed semicolons

src/index.ts

@@ -686,10 +686,7 @@ export class BufferedChangeset implements IChangeset {
    * @method restore
    */
   restore({ changes, errors }: Snapshot): this {
-    let newChanges: Changes = keys(changes).reduce((newObj: Changes, key: keyof Changes) => {
-      newObj[key] = new Change(changes[key]);
-      return newObj;
-    }, {});
+    let newChanges: Changes = this.getChangesFromSnapshot(changes);
 
     let newErrors: Errors<any> = keys(errors).reduce((newObj: Errors<any>, key: keyof Changes) => {
       let e: IErr<any> = errors[key];
@@ -707,6 +704,24 @@ export class BufferedChangeset implements IChangeset {
     return this;
   }
 
+  private getChangesFromSnapshot(changes: Changes) {
+    return keys(changes).reduce((newObj, key) => {
+      newObj[key] = this.getChangeForProp(changes[key]);
+      return newObj;
+    }, {} as Changes);
+  }
+
+  private getChangeForProp(value: any) {
+    if (!isObject(value)) {
+      return new Change(value);
+    }
+
+    return keys(value).reduce((newObj, key) => {
+      newObj[key] = this.getChangeForProp(value[key]);
+      return newObj;
+    }, {} as Changes);
+  }
+
   /**
    * Unlike `Ecto.Changeset.cast`, `cast` will take allowed keys and
    * remove unwanted keys off of the changeset. For example, this method

test/index.test.ts

@@ -3223,6 +3223,10 @@ describe('Unit | Utility | changeset', () => {
 
     expect(changeset.get('name')).toBe('Jim Bob');
     expect(changeset.get('address.country')).toBe('North Korea');
+    expect(changeset.changes).toEqual([
+      { key: 'name', value: 'Jim Bob' },
+      { key: 'address.country', value: 'North Korea' }
+    ]);
   });
 
   /**