How does EmberJS deal with different output between findRecord() & findAll()?

Let's say I have a simple model my-data:

export default Model.extend({
  foo: attr(),
  bar: attr()
});

Let's also say my backend is setup so when I use findAll() which calls /api/v1/my-data/, the response only returns the foo attribute, but if I use findRecord() -- eg, /api/v1/my-data/5 --, the response contains both foo and bar.

Is EmberJS smart enough to merge these two responses without overwriting any attribute that's not in the response? In other words, if I first do a findRecord('my-data', 5), then both foo & bar will be set, but if I subsequently call findAll(), which will also contain record 5, can I expect the record with id 5 to still have both foo and bar set, or will findAll() completely overwrite record 5 with bar becoming unset or NULL?