PaulUithol
Update backbone-relational.js
Assume, that I have model Zoo with relation to animals. If I use save() method with wait: true to update & save the model and provide new animals as a list of IDs (like {animals: [1,23,43]} ), toJSON method in backbone-relations.js fails on value = value.concat(rel.keyIds), because value is null.
This is because Backbone does not use set() method in save() if wait is True - it's only make a simple copy of provided attributes and set as model's attributes. The relation (that is an attribute of course) is not initialized so is not a model (for HasOne relation), or Collection (for HasMany relation), but contains simple value like Number, String or Array (depends on the type of relation and the data I set), which are keys for relation.
This pull request fix this bug and add additional check to toJSON method. If relation value is not a model or collection and is not empty assume that is a raw data and should be returned "as is". toJSON method returns list of related object keys, I used a related object keys in attributes object for Backbone.save() method, so everything is OK.
Wouldn't you have the same issue if includeInJSON were true or an array (the other two cases in toJSON)? And could you add a test case for this change?
