test(document): repro #7302

test/document.test.js

@@ -4984,6 +4984,27 @@ describe('document', function() {
       done();
     });
 
+    it('Handles setting populated path set via `Document#populate()` (gh-7302)', function() {
+      var authorSchema = new Schema({ name: String });
+      var bookSchema = new Schema({
+        author: { type: mongoose.Schema.Types.ObjectId, ref: 'gh7302_Author' }
+      });
+
+      var Author = db.model('gh7302_Author', authorSchema);
+      var Book = db.model('gh7302_Book', bookSchema);
+
+      return Author.create({ name: 'Victor Hugo' }).
+        then(author => Book.create({ author: author._id })).
+        then(() => Book.findOne()).
+        then(doc => doc.populate('author').execPopulate()).
+        then(doc => {
+          doc.author = {};
+          assert.ok(!doc.author.name);
+          assert.ifError(doc.validateSync());
+        });
+    });
+
+
     it('Single nested subdocs using discriminator can be modified (gh-5693)', function(done) {
       var eventSchema = new Schema({ message: String }, {
         discriminatorKey: 'kind',