documentcloud/backbone — pull request #1743 by mlowicki (2012-10-16 16:41:11+00:00)
Title: Input model passed to Backbone.Model#set shouldn't be cleared.

Previously:
var foo = new Backbone.Model({p: 1});
var bar = new Backbone.Model({p: 2});
bar.set(foo, {unset: true});
console.info(foo.get('p'));
console.info(bar.get('p'));

Displayed

> undefined
> undefined

Expected behaviour would be:

> 1
> undefined

Input model was even reset directly through 'attributes' property.