Hi Michael
On 11/01/2024 23:33, Michael Lohmann wrote:
This extends the functionality of `git log --merge` to also work with
conflicts for rebase, cherry pick and revert.
Signed-off-by: Michael Lohmann <mi.al.lohmann@xxxxxxxxx>
---
Hi everybody!
When Phillip Wood gave me some nice hints on his workflow concerning
conflicts [1] (we discussed if `--show-current-patch` would make sense
for cherry pick/revert). When I learned about `git log --merge` I was a
bit sad to discover that those do not exist for rebase/revert/cherry
pick since they look really valuable for getting an understanding on
what was changed. It is basically the counterpart to
`git show ${ACTION}_HEAD` for understanding the source of the conflict.
I am curious if also other people would be interested in having an easy
way to get a log of only the relevant commits touching conflicting files
for said actions.
With this patch I think the functionality is there, just hijacking the
`--merge` code - maybe an alias like `git log --conflict` or similar
might be more descriptive now?
What do you think about this idea? (Or am I maybe missing an easy way to
achieve it with the existing code as well?)
I should start by saying that I didn't know "git log --merge" existed
before I saw this message so please correct me if I've misunderstood
what this patch is doing. If I understand correctly it shows the commits
from each side of the merge and is equivalent to
git log HEAD MERGE_HEAD ^$(git merge-base HEAD MERGE_HEAD)
When a commit is cherry-picked the merge base used is CHERRY_PICK_HEAD^
[*] so I'm not sure what
git log HEAD CHERRY_PICK_HEAD ^$(git merge-base HEAD CHERRY_PICK_HEAD)
tells us. Indeed there HEAD and CHERRY_PICK_HEAD may not share a common
ancestor. As I say I've not used "git log --merge" so maybe I'm missing
the reason why it would be useful when cherry-picking or rebasing.
Best Wishes
Phillip
[*] assuming we're not picking a merge commit
Michael
[1] https://lore.kernel.org/git/cfba7098-3c23-4a81-933c-b7fefdedec8a@xxxxxxxxx/
revision.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/revision.c b/revision.c
index 2424c9bd67..2e5c00dabd 100644
--- a/revision.c
+++ b/revision.c
@@ -1961,23 +1961,37 @@ static void add_pending_commit_list(struct rev_info *revs,
}
}
+static char* get_action_head_name(struct object_id* oid)
+{
+ if (!repo_get_oid(the_repository, "MERGE_HEAD", oid)) {
+ return "MERGE_HEAD";
+ } else if (!repo_get_oid(the_repository, "REBASE_HEAD", oid)) {
+ return "REBASE_HEAD";
+ } else if (!repo_get_oid(the_repository, "CHERRY_PICK_HEAD", oid)) {
+ return "CHERRY_PICK_HEAD";
+ } else if (!repo_get_oid(the_repository, "REVERT_HEAD", oid)) {
+ return "REVERT_HEAD";
+ } else
+ die("--merge without MERGE_HEAD, REBASE_HEAD, CHERRY_PICK_HEAD or REVERT_HEAD?");
+}
+
static void prepare_show_merge(struct rev_info *revs)
{
struct commit_list *bases;
struct commit *head, *other;
struct object_id oid;
const char **prune = NULL;
+ const char *action_head_name;
int i, prune_num = 1; /* counting terminating NULL */
struct index_state *istate = revs->repo->index;
if (repo_get_oid(the_repository, "HEAD", &oid))
die("--merge without HEAD?");
head = lookup_commit_or_die(&oid, "HEAD");
- if (repo_get_oid(the_repository, "MERGE_HEAD", &oid))
- die("--merge without MERGE_HEAD?");
- other = lookup_commit_or_die(&oid, "MERGE_HEAD");
+ action_head_name = get_action_head_name(&oid);
+ other = lookup_commit_or_die(&oid, action_head_name);
add_pending_object(revs, &head->object, "HEAD");
- add_pending_object(revs, &other->object, "MERGE_HEAD");
+ add_pending_object(revs, &other->object, action_head_name);
bases = repo_get_merge_bases(the_repository, head, other);
add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
