[shane_kerns]

I believe that even git would work in this scenario because a.txt and b.txt are separate and independent thus a rebase in git is not required. The point at which this becomes an issue is when both person A and B try to make changes to the same file and specifically the same blob of text within that file. I could be wrong but this should be simple enough to prove out because I've run into this situation before where I forgot to rebase before pushing my changes but git still accepted the changes as they were independent of the changes that person B made.

[jacoblambda]

git wouldn't accept a push with conflicting changes on the remote but that's just because pushes are dumb (not bad, they just don't do anything fancy).

The solution would be to pull upstream changes (so you know what you are potentially pushing your changes into) and then push.

[Arelius]

> thus a rebase in git is not required.

A rebase is never required in Git. (people/maintainers may disagre) but a merge will always do.

Having said that. In your scenario provided, a pull + merge/rebase will be required. It will then resolve automatically, and without conflicts. But a human has to be involved to provide a strict sequence/dag of the those commits.