documentcloud/underscore — pull request #447 by jackcviers (2012-01-27 04:21:20+00:00)
Title: _.isDate() error fix. 

... Date().toString() outputs a date string of the format Thu Jan 26 2012 22:17:17 GMT-0600 (CST)

. A more comprehensive test is to check for the existence of a date property, such as the date function getFullYear(). In addition, if somebody were to extend Date(), this _.isDate will detect that the object is still a Date object.