In rebase, one can pass the `--autostash` option to cause the worktree
to be automatically stashed before continuing with the rebase. This
option is missing in merge, however.
Implement the `--autostash` option and corresponding `merge.autoStash`
option in merge which stashes before merging and then pops after.
This option is useful when a developer has some local changes on a topic
branch but they realize that their work depends on another branch.
Previously, they had to run something like
When an autostash is generated, it is automatically reapplied to the
worktree only in three explicit situations:
1. An incomplete merge is commit using `git commit`.
2. A merge completes successfully.
3. A merge is aborted using `git merge --abort`.
In all other situations where the merge state is removed using
remove_merge_branch_state() such as aborting a merge via
`git reset --hard`, the autostash is saved into the stash reflog
instead keeping the worktree clean.
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk> Suggested-by: Alban Gruin <alban.gruin@gmail.com> Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>