Running Gruntfiles from hub in dependency order

[vergenzt]

Hey @shama,

I've been working on a private fork of grunt-hub that adds a (pretty big) feature: the ability to run sub-Gruntfiles in dependency order (e.g. implicitly specify that project1/Gruntfile.js depends on project2/Gruntfile.js, and given that have the hub Gruntfile build project2 before project1). We've been needing this internally at my company and your codebase seemed like the most logical place to start.

It works by adding an option to hub targets called dependencyFn, a function which takes in (1) a Gruntfile path and (2) the set of Gruntfiles known by this hub target, and returns an array of Gruntfiles that the given Gruntfile depends on. The user can either provide their own implementation, or give a string referring to one of the default implementations. (Currently, we've only implemented "bower" to find relative dependencies in a bower.json and depend on any Gruntfiles in them, but it'd be easy to add any other common cases.)

Would you be open to merging this back into grunt-hub? I haven't fully tested yet to be sure, but I believe the only back-compat break is that support for specifying the level of concurrency is dropped (it uses maximum concurrency by default due to a switch from using async.queue to async.auto)--but that may be fixable if it's important. It's also a substantial rewrite of the majority of hub.js.

Let me know what you think!

[shama]

Sounds intriguing. I'm open to consider merging if you wanted to through a PR at me. Thanks!

[vergenzt]

Sweet. I'm working on consolidating things a bit so the diff isn't just a wall of changes. I'll open a PR today or tomorrow.