Improve support for nested keys

integration/test/ParseObjectTest.js

@@ -401,6 +401,20 @@ describe('Parse Object', () => {
     assert.equal(result.get('objectField').number, 20);
   });
 
+  it('can set non existing nested fields to objects', async () => {
+    const o = new Parse.Object('Person');
+    expect(o.attributes).toEqual({});
+    o.set('data', {});
+    await o.save();
+    expect(o.get('data')).toEqual({});
+    o.set('data.a', {});
+    await o.save();
+    expect(o.get('data')).toEqual({ a: {} });
+    o.set('data.a.b', {});
+    await o.save();
+    expect(o.get('data')).toEqual({ a: { b: {} } });
+  });
+
   it('can set non existing fields', async () => {
     const obj = new TestObject();
     obj.set('objectField', { number: 5 });

integration/test/ParseUserTest.js

@@ -505,7 +505,7 @@ describe('Parse User', () => {
         return user.save();
       })
       .then(() => {
-        assert.equal(Object.keys(user.attributes).length, 6);
+        assert.equal(Object.keys(user.attributes).length, 5);
         assert(user.attributes.hasOwnProperty('username'));
         assert(user.attributes.hasOwnProperty('email'));
         return user.destroy();

src/ObjectStateMutations.js

@@ -154,14 +154,27 @@ export function estimateAttributes(
   return data;
 }
 
+function nestedSet(obj, key, value) {
+  const path = key.split('.');
+  for (let i = 0; i < path.length - 1; i++) {
+    if (!(path[i] in obj)) obj[path[i]] = {};
+    obj = obj[path[i]];
+  }
+  if (typeof value === 'undefined') {
+    delete obj[path[path.length - 1]];
+  } else {
+    obj[path[path.length - 1]] = value;
+  }
+}
+
 export function commitServerChanges(
   serverData: AttributeMap,
   objectCache: ObjectCache,
   changes: AttributeMap
 ) {
   for (const attr in changes) {
     const val = changes[attr];
-    serverData[attr] = val;
+    nestedSet(serverData, attr, val);
     if (
       val &&
       typeof val === 'object' &&

src/ParseObject.js

@@ -409,7 +409,7 @@ class ParseObject {
     for (attr in pending) {
       if (pending[attr] instanceof RelationOp) {
         changes[attr] = pending[attr].applyTo(undefined, this, attr);
-      } else if (!(attr in response) && !attr.includes('.')) {
+      } else if (!(attr in response)) {
         // Only SetOps and UnsetOps should not come back with results
         changes[attr] = pending[attr].applyTo(undefined);
       }