We need to support one to one relationships
I just stumbled upon this. The README on current master describes under "Associations" that you can setup a OneToOne association by specifying belongsTo on both ends. But d5669dd just assumes that on the other end of a belongsTo is a hasMany. If there isn't, it will fail with "Cannot call method 'indexOf' of undefined".
@tchak This is still an issue in master, right?
@wagenet Definitely still an issue.
We've submitted an implementation with #475.