Re: reject "backwards" merges

Patrick Donnelly [off-list ref] writes:

Is there a way to reject pushes that change the history of
first-parents, caused by a "backwards" merge? To clarify by example
(using branches instead of separate repositories):

Here the desired first parent (HEAD^) would be commit
9cb303e2578af305d688abf62570ef31f3f113da. Unfortunately, the incorrect
merge reversed the line of parents. Is there a way to prevent this
from happening (via git-config) other than fixing the human?

You'd have to do this in a push hook.  Before pushing, Git does not
really have a way to figure out which kind of branch a merge will land
on.

Most "reversed merges" probably come into being by having a fast-forward
in a series of zig-zagged merges.  Naturally the history before the
fast-forward can only be "the right way round" for one of the two
branches.

-- 
David Kastrup