Alexis Praga <alexis.praga@gmail.com> asked about a feature akin to 
`git push --force` in darcs. In addition to adding local patches 
that are not in the remote repo, this would also obliterate remote 
patches that are not in the local repo. Since push is send plus a 
remote apply, such an option would first have to be implemented for 
apply.

The option should display a prominent warning, listing the patches 
to be obliterated.

Should be easy to implement, even for a newcomer (with some 
guidance).

Another name for the option could be --mirror.

Attached is a patch that implements apply --mirror, including a small 
test script. This is WIP as there is no warning yet, and no way to 
interactively select the patches to obliterate.

It occurred to me that this idea could be generalized to provide user-
selectable merge strategies. Given a set of patches to apply (them) and 
an existing set (us), with all common patches already removed, we could 
offer:

 - default: standard merge, possibly resulting in conflicts,
   details depend on --mark-conflicts/--allow-conflicts/...
 - mirror: replace us with them (this one)
 - remove-conflicting: remove only our conflicting patches
 - suspend: suspend all our existing patches
 - suspend-conflicting: suspend (only) our conflicting patches 
 - skip-conflicting: add only their non-conflicting patches

The versions wich suspend or remove existing patches in the target repo 
could support interactive selection, possibly resulting in a "mixed 
mode" strategy, where we first obliterate or suspend the selected 
patches and then fall back to the default merge for the rest.

Attachments

• wip-first-preliminary-implementation-of-apply-__mirror.dpatch