Submodule init is easy to miss when hacking on Brackets

[peterflynn]

Forgetting to run git submodule update --init seems like the most common pitfall people hit when following the How to Hack on Brackets guide. Is there anything we could do to reduce the likelihood of that?

• It's already called out in "Getting a Copy of the Code," but people might skip that section if they feel like they already know how to clone repos. Should we add a note elsewhere in the wiki page?
• We could try to detect missing submodules during Brackets startup and show a warning (perhaps similar to how we detect in-browser). But that would be fragile code that'd be hard to maintain.
• We could have the "setup_for_hacking" script check for missing submodules and issue an error/warning. That seems simple and fairly easy to maintain.

[peterflynn]

If anyone knows both shell scripts and .bat scripting, the third idea should be pretty easy to implement :-)

[njx]

That would be useful, though it only addresses initial setup--it's also easy to forget to update submodules later on.

It might be easy to put a check in Brackets that checks if you're running out of a git repo, checks the desired SHAs for the submodules, and then checks that the HEAD of each submodule matches the SHA. I don't know where the expected SHA is stored in the main repo, but once we figure that out it would be pretty easy to check.

[njx]

Actually, it looks like it's not easy to determine the expected SHA without actually using git commands--it's stored directly in the object database.

[tomekr]

I just started with environment initialization and this happened to me. I believe the problem is when you're going through the How to Hack on Brackets page, you reach the part where it says, "See Running Your Copy of the Code for more details." under the "How Brackets is Organized" section.

At this point I'm thinking, "Hell yeah I want to eat my own dog food!" I click on the link which sends me to the "Running Your Copy of the Code" section, skipping over the "Getting a Copy of the Code" section which has the initialization snippet.

I think this can be mitigated by adding a section in the Running Your Copy of the Code, instructing the user to ensure they've completed the "Getting a Copy of the Code" section.

[pthiess]

Reviewed

[peterflynn]

Nominating for Sprint 19 since we continue to get frequent reports of this, and it seems hard for people to figure out on their own (especially since it's not obvious how to open the dev tools when the UI is blank).

[jdiehl]

I saw this issue a bit late so my fix #2440 for it (implementing the second option) might not be relevant. However, it seems simple enough to maintain and can serve as a temporary solution or to double-check the third way of checking this.

[njx]

FBNC to @peterflynn -- it looks like we merged @jdiehl's solution.

[njx]

Oops, I forgot to actually assign this back to Peter.

[peterflynn]

Verified fixed. I also took @tomekr's advice and tweaked the wiki instructions to make submodule update harder to gloss over.