Currently user must plugin device, even the one only want to build Gecko, not the full image. Thinker has told me for Gecko, this should be definitely possible, and according to the experiments I've done it is true. So I would submit a patch for it.
Created attachment 8603905 [details] [review] Patch Don't know if I'm doing it right, but test on my local console it works. So set review.
This is useful and time-saving!
What devices have you tested this on? How did you test?
Flame-kk; I've done |config.sh flame-kk| and built it with my modified |build.sh| to command |build.sh gecko|. After built successfully, I flashed it to my device (Flame v1.8D), and tested it via opening some apps and it looks all fine.
You'll need to make sure the vendor/t2m directory is deleted first - that holds the output of extract-files.sh. Additionally, the phone only needs to plugged in once. extract-files.sh backups up the phone's system partition to the backup-* directories and never checks again. It's possible to just download a backup directory instead of plugging the phone in.
I'm sure the vender directory and others I've mentioned is removed before I did the test. To make sure, I just built it again, and success again. I think the backup-flame is not able to be distributed (download) because of legal issue. So if I can avoid it, we may save a lots of time and pain to provide a nightly Gecko build for community members, which according to our claim that brings Web to mobile, are the front-end people that may never "build" things complicated than a Node.js server, not to mention a huge C++ project like Gecko or B2g.
And if it's risky to skip the step by default, I could submit a patch to add an option to avoid the backing step optionally.