visionmedia/should.js — pull request #88 by alFReD-NSH (2012-11-02 06:27:14+00:00)
Title: Fix should[.not].exist not having stack trace #84

This was because should wasn't defined in that context and was referring
to should property of the `global` object which is from the prototype.
So `should.exist` and `should.not.exist` were undefined, which made
stackStartFunction properties in those functions undefined.