When recreating merge conflicts with "git checkout -m <path>" the
original conflict labels are lost. For commands like "git merge" and
"git cherry-pick" we could use the presence of the related root
ref (MERGE_HEAD and CHERRY_PICK_HEAD respectively) to recreate the
labels. However, if the conflicts are from "git stash pop" or "git
checkout -m <branch>", then there is no ref to deduce the labels from. To
ensure the labels are always available, the merge machinery is updated to
write ".git/MERGE_LABELS" when it updates the worktree and
there are conflicts. The labels are then read from that file by "git
checkout -m <path>" when recreating the conflicts.
As "git checkout -m <branch>" calls remove_branch_state() which
ordinarily removes the labels file, we need to pass a flag down
to optionally prevent that so that the labels are available for any
subsequent "git checkout -m <path>". Note that merge_switch_to_result()
we assign "result->priv" to "opt->priv" and later clear "opt->priv" in
order to get a pointer to the private struct as result->priv is void*.
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Phillip Wood
d5f4e42f02