jdalton/underscore — comment on commit 3c6a8ccd73c88e0329df094d210c03620c21e8e2
File: underscore.js line 722
By jdalton:

question:
I noticed _.defaults does `if (obj[key] == null)`.
Is it more correct to do one that checks hasOwnProp check `if (hasOwnProperty.call(obj, key) && obj[key] == null)`?
That way thinks like:

~~~ js
_.defaults(options, {zero: 1, one: 10, twenty: 20, toString: function() { 'foo'; }});
~~~

would be doable.