document how to keep sources up to date

[doniks]

Sooner or later one has to update the source tree to get upstream changes.

Everytime I embark about it it becomes a mess. Could some repo/git wizzard please document how to do this properly?

I try usually start with repo sync then I cycle between repo sync --force-sync something/or/another after guessing on some cryptic repo errors. I repeat this until I can't find any cryptic errors anymore. Just now, I did it and it took a good dozen times.

If I have any local work in progress code changes which I am not ready to publish to a public branch it gets a lot more complicated even. Then I get errors like error: Cannot remove project "some/project": uncommitted changes are present. Now starts a fun process of making backups by copying files with local modifications around, or creating other git branches, then deleting changes, until repo sync passes, then even more fun of trying to get my work in progress changes back.

There has to be a sane way to do this.