[2.0.0] `Cannot read property '_internalModel' of undefined` when saving changeset created off relationship

Version

2.0.0

Test Case

https://ember-twiddle.com/71783e0988666e55502dfdafadc55145 The test case is basically two model instances with a one-to-one relationship. When creating a changeset like new Changeset(this.model.post), save won’t work properly on the changeset.

Steps to reproduce

Click the save button in the twiddle and the error is thrown.

Expected Behavior

Save works properly

Actual Behavior

Somehow the scope is lost when saving the changeset, thus this is undefined. The spot where it’s going wrong is this branch of the save code: https://github.com/poteto/ember-changeset/blob/d2f9cbe8d6d8f7b774fc51a39d5bdfc7c2df9fc5/addon/index.ts#L227-L235

[snewcomer]

v3.6.0!

[nickschot]

I am not 100% sure, the changeset is definitely working before fully resolving it. I think by adding it in the save method we just add support for passing a relationship and not for records that haven’t been loaded yet.

Going to dig a little more this week.