New Precommit Grunt Task to avoid __DIR__ and 5.3+ stuff in Core.

[georgestephanis]

As was noted in [30311], a __DIR__ crept in, which isn't available in 5.2.

This sounds like an ideal case for Grunt scanning for instances in the future to prevent future 'oops' commits.

[georgestephanis]

This could easily be extended to also check for shorttags and other stuffs.

​https://www.npmjs.org/package/grunt-search

[jorbin]

While there are a number of things we can't catch from simply scanning the code, this will help us catch some of them.

[nacin]

Is this a good use case of Grunt? Seems more like Codesniffer or PHP 5.2 syntax checking. Though __DIR__ doesn't trigger a syntax error in 5.2, __DIR__ isn't the common issue. It's some other PHP 5.3-ism, usually, and ones that trigger a fatal or syntax error.

The number of times a __DIR__ has entered core is, best I can tell from a search of commit logs, 1.

[jorbin]

I agree with Nacin. As I had mentioned in slack earlier: :At first I really liked the idea of using grunt-search, but I think phpcodesniffer is actually what we should be using in this situation. I would rather us work on getting #30153 done and then we can write a sniff for dir if one does not exist already.