# [PATCH v4 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge 26 messages from 2024-02-10 to 2024-03-02. Participants: Philippe Blain, Johannes Sixt, Phillip Wood, Junio C Hamano, Jean-Noël Avila, phillip.wood123@gmail.com. Thread: https://gitlist.dev/t/60897 ## Philippe Blain, 2024-02-10 23:35 Subject: [PATCH v4 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge Message-ID: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-1-3bc9e62808f4@gmail.com> URL: https://gitlist.dev/e/20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-1-3bc9e62808f4%40gmail.com In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-0-3bc9e62808f4@gmail.com> ``` From: Michael Lohmann This is done to (1) ensure MERGE_HEAD is a ref, (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() (3) error out when MERGE_HEAD is a symref. Helped-by: Junio C Hamano Signed-off-by: Michael Lohmann Signed-off-by: Junio C Hamano --- revision.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/revision.c b/revision.c index 2424c9bd67..aa4c4dc778 100644 --- a/revision.c +++ b/revision.c @@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs) 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)) + if (read_ref_full("MERGE_HEAD", + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + &oid, NULL)) die("--merge without MERGE_HEAD?"); + if (is_null_oid(&oid)) + die("MERGE_HEAD is a symbolic ref???"); other = lookup_commit_or_die(&oid, "MERGE_HEAD"); add_pending_object(revs, &head->object, "HEAD"); add_pending_object(revs, &other->object, "MERGE_HEAD"); -- 2.39.1 ``` ## Philippe Blain, 2024-02-10 23:35 Subject: [PATCH v4 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-0-3bc9e62808f4@gmail.com> URL: https://gitlist.dev/e/20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-0-3bc9e62808f4%40gmail.com In-Reply-To: <20240117081405.14012-1-mi.al.lohmann@gmail.com> ``` Changes in v4: - Added a commit message for 2/2 detailing the use case and summarizing the discussion in the thread - Adjusted the documentation of the option Link to v3: https://lore.kernel.org/r/20240117081405.14012-1-mi.al.lohmann@gmail.com Range-diff vs v3: 1: 37405be1a3 = 1: 37405be1a3 revision: ensure MERGE_HEAD is a ref in prepare_show_merge 2: de080a628c ! 2: 6ac1608809 revision: implement `git log --merge` also for rebase/cherry_pick/revert @@ Metadata Author: Michael Lohmann ## Commit message ## - revision: implement `git log --merge` also for rebase/cherry_pick/revert + revision: implement `git log --merge` also for rebase/cherry-pick/revert + 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], + 2006-07-03) to show commits touching conflicted files in the range + HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document + rev-list's option --merge, 2006-08-04). + + It can be useful to look at the commit history to understand what lead + to merge conflicts also for other mergy operations besides merges, like + cherry-pick, revert and rebase. + + For rebases, an interesting range to look at is HEAD...REBASE_HEAD, + since the conflicts are usually caused by how the code changed + differently on HEAD since REBASE_HEAD forked from it. + + For cherry-picks and revert, it is less clear that + HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting + ranges, since these commands are about applying or unapplying a single + (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts + encountered during these operations can indeed be caused by changes + introduced in preceding commits on both sides of the history. + + Adjust the code in prepare_show_merge so it constructs the range + HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, + REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, + so keep REBASE_HEAD last since the three other operations can be + performed during a rebase. Note also that in the uncommon case where + $OTHER and HEAD do not share a common ancestor, this will show the + complete histories of both sides since their root commits, which is the + same behaviour as currently happens in that case for HEAD and + MERGE_HEAD. + + Adjust the documentation of this option accordingly. + + Co-authored-by: Philippe Blain Co-authored-by: Johannes Sixt + Signed-off-by: Philippe Blain Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano + ## Documentation/gitk.txt ## +@@ Documentation/gitk.txt: linkgit:git-rev-list[1] for a complete list. + + --merge:: + +- After an attempt to merge stops with conflicts, show the commits on +- the history between two branches (i.e. the HEAD and the MERGE_HEAD) +- that modify the conflicted files and do not exist on all the heads +- being merged. ++ Show commits touching conflicted paths in the range `HEAD...$OTHER`, ++ where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, ++ `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works ++ when the index has unmerged entries. + + --left-right:: + + + ## Documentation/rev-list-options.txt ## +@@ Documentation/rev-list-options.txt: See also linkgit:git-reflog[1]. + Under `--pretty=reference`, this information will not be shown at all. + + --merge:: +- After a failed merge, show refs that touch files having a +- conflict and don't exist on all heads to merge. ++ Show commits touching conflicted paths in the range `HEAD...$OTHER`, ++ where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, ++ `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works ++ when the index has unmerged entries. + + --boundary:: + Output excluded boundary commits. Boundary commits are + ## revision.c ## @@ revision.c: static void add_pending_commit_list(struct rev_info *revs, } --- Michael Lohmann (2): revision: ensure MERGE_HEAD is a ref in prepare_show_merge revision: implement `git log --merge` also for rebase/cherry-pick/revert Documentation/gitk.txt | 8 ++++---- Documentation/rev-list-options.txt | 6 ++++-- revision.c | 27 +++++++++++++++++++++++---- 3 files changed, 31 insertions(+), 10 deletions(-) --- base-commit: 186b115d3062e6230ee296d1ddaa0c4b72a464b5 change-id: 20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-05bd8e8797db ``` ## Philippe Blain, 2024-02-10 23:35 Subject: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-2-3bc9e62808f4@gmail.com> URL: https://gitlist.dev/e/20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-2-3bc9e62808f4%40gmail.com In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-0-3bc9e62808f4@gmail.com> ``` From: Michael Lohmann 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], 2006-07-03) to show commits touching conflicted files in the range HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document rev-list's option --merge, 2006-08-04). It can be useful to look at the commit history to understand what lead to merge conflicts also for other mergy operations besides merges, like cherry-pick, revert and rebase. For rebases, an interesting range to look at is HEAD...REBASE_HEAD, since the conflicts are usually caused by how the code changed differently on HEAD since REBASE_HEAD forked from it. For cherry-picks and revert, it is less clear that HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting ranges, since these commands are about applying or unapplying a single (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts encountered during these operations can indeed be caused by changes introduced in preceding commits on both sides of the history. Adjust the code in prepare_show_merge so it constructs the range HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, so keep REBASE_HEAD last since the three other operations can be performed during a rebase. Note also that in the uncommon case where $OTHER and HEAD do not share a common ancestor, this will show the complete histories of both sides since their root commits, which is the same behaviour as currently happens in that case for HEAD and MERGE_HEAD. Adjust the documentation of this option accordingly. Co-authored-by: Philippe Blain Co-authored-by: Johannes Sixt Signed-off-by: Philippe Blain Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano --- Documentation/gitk.txt | 8 ++++---- Documentation/rev-list-options.txt | 6 ++++-- revision.c | 31 +++++++++++++++++++++++-------- 3 files changed, 31 insertions(+), 14 deletions(-) diff --git a/Documentation/gitk.txt b/Documentation/gitk.txt index c2213bb77b..80ff4e149a 100644 --- a/Documentation/gitk.txt +++ b/Documentation/gitk.txt @@ -63,10 +63,10 @@ linkgit:git-rev-list[1] for a complete list. --merge:: - After an attempt to merge stops with conflicts, show the commits on - the history between two branches (i.e. the HEAD and the MERGE_HEAD) - that modify the conflicted files and do not exist on all the heads - being merged. + Show commits touching conflicted paths in the range `HEAD...$OTHER`, + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works + when the index has unmerged entries. --left-right:: diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index 2bf239ff03..5b4672c346 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -341,8 +341,10 @@ See also linkgit:git-reflog[1]. Under `--pretty=reference`, this information will not be shown at all. --merge:: - After a failed merge, show refs that touch files having a - conflict and don't exist on all heads to merge. + Show commits touching conflicted paths in the range `HEAD...$OTHER`, + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works + when the index has unmerged entries. --boundary:: Output excluded boundary commits. Boundary commits are diff --git a/revision.c b/revision.c index aa4c4dc778..36dc2f94f7 100644 --- a/revision.c +++ b/revision.c @@ -1961,11 +1961,31 @@ static void add_pending_commit_list(struct rev_info *revs, } } +static const char *lookup_other_head(struct object_id *oid) +{ + int i; + static const char *const other_head[] = { + "MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD" + }; + + for (i = 0; i < ARRAY_SIZE(other_head); i++) + if (!read_ref_full(other_head[i], + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + oid, NULL)) { + if (is_null_oid(oid)) + die("%s is a symbolic ref???", other_head[i]); + return other_head[i]; + } + + die("--merge without MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD?"); +} + static void prepare_show_merge(struct rev_info *revs) { struct commit_list *bases; struct commit *head, *other; struct object_id oid; + const char *other_name; const char **prune = NULL; int i, prune_num = 1; /* counting terminating NULL */ struct index_state *istate = revs->repo->index; @@ -1973,15 +1993,10 @@ static void prepare_show_merge(struct rev_info *revs) if (repo_get_oid(the_repository, "HEAD", &oid)) die("--merge without HEAD?"); head = lookup_commit_or_die(&oid, "HEAD"); - if (read_ref_full("MERGE_HEAD", - RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, - &oid, NULL)) - die("--merge without MERGE_HEAD?"); - if (is_null_oid(&oid)) - die("MERGE_HEAD is a symbolic ref???"); - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); + other_name = lookup_other_head(&oid); + other = lookup_commit_or_die(&oid, other_name); add_pending_object(revs, &head->object, "HEAD"); - add_pending_object(revs, &other->object, "MERGE_HEAD"); + add_pending_object(revs, &other->object, other_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); -- 2.39.1 ``` ## Johannes Sixt, 2024-02-11 08:34 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <2cf557e9-bf48-4bf3-be24-c1eeaa887418@kdbg.org> URL: https://gitlist.dev/e/2cf557e9-bf48-4bf3-be24-c1eeaa887418%40kdbg.org In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-2-3bc9e62808f4@gmail.com> ``` Thank you for stepping in and resubmitting with an extended commit message and documentation! Am 11.02.24 um 00:35 schrieb Philippe Blain: > From: Michael Lohmann > > 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], > 2006-07-03) to show commits touching conflicted files in the range > HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document > rev-list's option --merge, 2006-08-04). > > It can be useful to look at the commit history to understand what lead > to merge conflicts also for other mergy operations besides merges, like > cherry-pick, revert and rebase. > > For rebases, an interesting range to look at is HEAD...REBASE_HEAD, > since the conflicts are usually caused by how the code changed > differently on HEAD since REBASE_HEAD forked from it. > > For cherry-picks and revert, it is less clear that > HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting > ranges, since these commands are about applying or unapplying a single > (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts > encountered during these operations can indeed be caused by changes > introduced in preceding commits on both sides of the history. I very much agree. Thank you for spelling it out! > Adjust the code in prepare_show_merge so it constructs the range > HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, > REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, > so keep REBASE_HEAD last since the three other operations can be > performed during a rebase. Note also that in the uncommon case where > $OTHER and HEAD do not share a common ancestor, this will show the > complete histories of both sides since their root commits, which is the > same behaviour as currently happens in that case for HEAD and > MERGE_HEAD. Well explained! > > Adjust the documentation of this option accordingly. > > Co-authored-by: Philippe Blain > Co-authored-by: Johannes Sixt > Signed-off-by: Philippe Blain > Signed-off-by: Michael Lohmann > [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] > Signed-off-by: Junio C Hamano Signed-off-by trailers should occur in temporal order. Therefore, when you pick up a commit and resend it, you should keep existing Signed-off-by and add yours last. > --- > Documentation/gitk.txt | 8 ++++---- > Documentation/rev-list-options.txt | 6 ++++-- > revision.c | 31 +++++++++++++++++++++++-------- > 3 files changed, 31 insertions(+), 14 deletions(-) > > diff --git a/Documentation/gitk.txt b/Documentation/gitk.txt > index c2213bb77b..80ff4e149a 100644 > --- a/Documentation/gitk.txt > +++ b/Documentation/gitk.txt > @@ -63,10 +63,10 @@ linkgit:git-rev-list[1] for a complete list. > > --merge:: > > - After an attempt to merge stops with conflicts, show the commits on > - the history between two branches (i.e. the HEAD and the MERGE_HEAD) > - that modify the conflicted files and do not exist on all the heads > - being merged. > + Show commits touching conflicted paths in the range `HEAD...$OTHER`, > + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, > + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works > + when the index has unmerged entries. Unfortunately, this patch does not help gitk. Gitk has its own logic to treat --merge and needs its own patch. This hunk should not be part of this patch. > > --left-right:: > > diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt > index 2bf239ff03..5b4672c346 100644 > --- a/Documentation/rev-list-options.txt > +++ b/Documentation/rev-list-options.txt > @@ -341,8 +341,10 @@ See also linkgit:git-reflog[1]. > Under `--pretty=reference`, this information will not be shown at all. > > --merge:: > - After a failed merge, show refs that touch files having a > - conflict and don't exist on all heads to merge. > + Show commits touching conflicted paths in the range `HEAD...$OTHER`, > + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, > + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works > + when the index has unmerged entries. Good. I used --left-right to check that the direction is indeed HEAD...$OTHER and not $OTHER...HEAD. -- Hannes ``` ## Philippe Blain, 2024-02-11 16:43 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <1c258037-cb08-5fbc-d473-743a60cd8eab@gmail.com> URL: https://gitlist.dev/e/1c258037-cb08-5fbc-d473-743a60cd8eab%40gmail.com In-Reply-To: <2cf557e9-bf48-4bf3-be24-c1eeaa887418@kdbg.org> ``` Hi Johannes, Le 2024-02-11 à 03:34, Johannes Sixt a écrit : >> Adjust the documentation of this option accordingly. >> >> Co-authored-by: Philippe Blain >> Co-authored-by: Johannes Sixt >> Signed-off-by: Philippe Blain >> Signed-off-by: Michael Lohmann >> [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] >> Signed-off-by: Junio C Hamano > > Signed-off-by trailers should occur in temporal order. Therefore, when > you pick up a commit and resend it, you should keep existing > Signed-off-by and add yours last. Thank you, I did not know that. I guess Junio should be kept last though ? Or maybe I should remove Junio's sign-off if I send a new version of the patch ? I'll resend with corrected order. By the way, Michael put you as co-author but did not add your signed-off-by... >> --- >> Documentation/gitk.txt | 8 ++++---- >> Documentation/rev-list-options.txt | 6 ++++-- >> revision.c | 31 +++++++++++++++++++++++-------- >> 3 files changed, 31 insertions(+), 14 deletions(-) >> >> diff --git a/Documentation/gitk.txt b/Documentation/gitk.txt >> index c2213bb77b..80ff4e149a 100644 >> --- a/Documentation/gitk.txt >> +++ b/Documentation/gitk.txt >> @@ -63,10 +63,10 @@ linkgit:git-rev-list[1] for a complete list. >> >> --merge:: >> >> - After an attempt to merge stops with conflicts, show the commits on >> - the history between two branches (i.e. the HEAD and the MERGE_HEAD) >> - that modify the conflicted files and do not exist on all the heads >> - being merged. >> + Show commits touching conflicted paths in the range `HEAD...$OTHER`, >> + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, >> + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works >> + when the index has unmerged entries. > > Unfortunately, this patch does not help gitk. Gitk has its own logic to > treat --merge and needs its own patch. This hunk should not be part of > this patch. Ah, you are right. I assumed it just used rev-list under the hood, but it's not the case for this flag. I'll remove that hunk. Thanks, Philippe. ``` ## Johannes Sixt, 2024-02-11 17:59 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <529c7b42-c606-408e-b6a3-fe189c28db9b@kdbg.org> URL: https://gitlist.dev/e/529c7b42-c606-408e-b6a3-fe189c28db9b%40kdbg.org In-Reply-To: <1c258037-cb08-5fbc-d473-743a60cd8eab@gmail.com> ``` Am 11.02.24 um 17:43 schrieb Philippe Blain: > Hi Johannes, > > Le 2024-02-11 à 03:34, Johannes Sixt a écrit : > >>> Adjust the documentation of this option accordingly. >>> >>> Co-authored-by: Philippe Blain >>> Co-authored-by: Johannes Sixt >>> Signed-off-by: Philippe Blain >>> Signed-off-by: Michael Lohmann >>> [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] >>> Signed-off-by: Junio C Hamano >> >> Signed-off-by trailers should occur in temporal order. Therefore, when >> you pick up a commit and resend it, you should keep existing >> Signed-off-by and add yours last. > > Thank you, I did not know that. I guess Junio should be kept last though ? > Or maybe I should remove Junio's sign-off if I send a new version of the > patch ? You should *not* remove Junio's Signed-off-by, because the patch went through his hands before you picked it up. Then you add your own sign-off below. Later, Junio will sign it off again. > I'll resend with corrected order. > > By the way, Michael put you as co-author but did not add your signed-off-by... This is fine and sufficient. Micheal used some of my ideas, but I didn't take part in the patch submission process. -- Hannes ``` ## Phillip Wood, 2024-02-12 11:02 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/c5d60b5b-3181-4bb7-a7f8-eb97474526d7%40gmail.com In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-2-3bc9e62808f4@gmail.com> ``` Hi Philippe On 10/02/2024 23:35, Philippe Blain wrote: > From: Michael Lohmann > > 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], > 2006-07-03) to show commits touching conflicted files in the range > HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document > rev-list's option --merge, 2006-08-04). > > It can be useful to look at the commit history to understand what lead > to merge conflicts also for other mergy operations besides merges, like > cherry-pick, revert and rebase. > > For rebases, an interesting range to look at is HEAD...REBASE_HEAD, > since the conflicts are usually caused by how the code changed > differently on HEAD since REBASE_HEAD forked from it. > > For cherry-picks and revert, it is less clear that > HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting > ranges, since these commands are about applying or unapplying a single > (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts > encountered during these operations can indeed be caused by changes > introduced in preceding commits on both sides of the history. I tend to think that there isn't much difference between rebase and cherry-pick here - they are both cherry-picking commits and it is perfectly possible to rebase a branch onto an unrelated upstream. The important part for me is that we're showing these commits because even though they aren't part of the 3-way merge they are relevant for investigating where any merge conflicts come from. For revert I'd argue that the only sane use is reverting an ancestor of HEAD but maybe I'm missing something. In that case REVERT_HEAD...HEAD is the same as REVERT_HEAD..HEAD so it shows the changes since the commit that is being reverted which will be the ones causing the conflict. > Adjust the code in prepare_show_merge so it constructs the range > HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, > REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, > so keep REBASE_HEAD last since the three other operations can be > performed during a rebase. Note also that in the uncommon case where > $OTHER and HEAD do not share a common ancestor, this will show the > complete histories of both sides since their root commits, which is the > same behaviour as currently happens in that case for HEAD and > MERGE_HEAD. > > Adjust the documentation of this option accordingly. Thanks for the comprehensive commit message. > diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt > index 2bf239ff03..5b4672c346 100644 > --- a/Documentation/rev-list-options.txt > +++ b/Documentation/rev-list-options.txt > @@ -341,8 +341,10 @@ See also linkgit:git-reflog[1]. > Under `--pretty=reference`, this information will not be shown at all. > > --merge:: > - After a failed merge, show refs that touch files having a > - conflict and don't exist on all heads to merge. > + Show commits touching conflicted paths in the range `HEAD...$OTHER`, > + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, > + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works > + when the index has unmerged entries. Do you know what "and don't exist on all heads to merge" in the original is referring to? The new text doesn't mention anything that sounds like that but I don't understand what the original was trying to say. It might be worth adding a sentence explaining when this option is useful. This option can be used to show the commits that are relevant when resolving conflicts from a 3-way merge or something like that. > --boundary:: > Output excluded boundary commits. Boundary commits are > diff --git a/revision.c b/revision.c > index aa4c4dc778..36dc2f94f7 100644 > --- a/revision.c > +++ b/revision.c > @@ -1961,11 +1961,31 @@ static void add_pending_commit_list(struct rev_info *revs, > } > } > > +static const char *lookup_other_head(struct object_id *oid) > +{ > + int i; > + static const char *const other_head[] = { > + "MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD" > + }; > + > + for (i = 0; i < ARRAY_SIZE(other_head); i++) > + if (!read_ref_full(other_head[i], > + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, > + oid, NULL)) { > + if (is_null_oid(oid)) > + die("%s is a symbolic ref???", other_head[i]); This would benefit from being translated and I think one '?' would suffice (I'm not sure we even need that - are there other possible causes of a null oid here?) > + return other_head[i]; > + } > + > + die("--merge without MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD?"); This is not a question and would also benefit from translation. It might be more helpful to say that "--merge" requires one of those pseudorefs. Thanks for pick this series up and polishing it Phillip ``` ## Junio C Hamano, 2024-02-12 18:27 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/xmqqmss55yhv.fsf%40gitster.g In-Reply-To: <529c7b42-c606-408e-b6a3-fe189c28db9b@kdbg.org> ``` Johannes Sixt writes: > Am 11.02.24 um 17:43 schrieb Philippe Blain: >> Hi Johannes, >> >> Le 2024-02-11 à 03:34, Johannes Sixt a écrit : >> >>>> Adjust the documentation of this option accordingly. >>>> >>>> Co-authored-by: Philippe Blain >>>> Co-authored-by: Johannes Sixt >>>> Signed-off-by: Philippe Blain >>>> Signed-off-by: Michael Lohmann >>>> [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] >>>> Signed-off-by: Junio C Hamano >>> >>> Signed-off-by trailers should occur in temporal order. Therefore, when >>> you pick up a commit and resend it, you should keep existing >>> Signed-off-by and add yours last. >> >> Thank you, I did not know that. I guess Junio should be kept last though ? >> Or maybe I should remove Junio's sign-off if I send a new version of the >> patch ? > > You should *not* remove Junio's Signed-off-by, because the patch went > through his hands before you picked it up. Then you add your own > sign-off below. Later, Junio will sign it off again. In the meantime, this is how I tweaked while queuing. Co-authored-by: Johannes Sixt Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano [pb: greatly enhanced the log message] Signed-off-by: Philippe Blain Signed-off-by: Junio C Hamano ``` ## Jean-Noël Avila, 2024-02-13 08:33 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <7a2a0ed5-f9dc-42dd-886b-457641b9bc79@gmail.com> URL: https://gitlist.dev/e/7a2a0ed5-f9dc-42dd-886b-457641b9bc79%40gmail.com In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-2-3bc9e62808f4@gmail.com> ``` Le 11/02/2024 à 00:35, Philippe Blain a écrit : > From: Michael Lohmann > > 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], > 2006-07-03) to show commits touching conflicted files in the range > HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document > rev-list's option --merge, 2006-08-04). > > It can be useful to look at the commit history to understand what lead > to merge conflicts also for other mergy operations besides merges, like > cherry-pick, revert and rebase. > > For rebases, an interesting range to look at is HEAD...REBASE_HEAD, > since the conflicts are usually caused by how the code changed > differently on HEAD since REBASE_HEAD forked from it. > > For cherry-picks and revert, it is less clear that > HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting > ranges, since these commands are about applying or unapplying a single > (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts > encountered during these operations can indeed be caused by changes > introduced in preceding commits on both sides of the history. > > Adjust the code in prepare_show_merge so it constructs the range > HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, > REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, > so keep REBASE_HEAD last since the three other operations can be > performed during a rebase. Note also that in the uncommon case where > $OTHER and HEAD do not share a common ancestor, this will show the > complete histories of both sides since their root commits, which is the > same behaviour as currently happens in that case for HEAD and > MERGE_HEAD. > > Adjust the documentation of this option accordingly. > > Co-authored-by: Philippe Blain > Co-authored-by: Johannes Sixt > Signed-off-by: Philippe Blain > Signed-off-by: Michael Lohmann > [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] > Signed-off-by: Junio C Hamano > --- > Documentation/gitk.txt | 8 ++++---- > Documentation/rev-list-options.txt | 6 ++++-- > revision.c | 31 +++++++++++++++++++++++-------- > 3 files changed, 31 insertions(+), 14 deletions(-) > > diff --git a/Documentation/gitk.txt b/Documentation/gitk.txt > index c2213bb77b..80ff4e149a 100644 > --- a/Documentation/gitk.txt > +++ b/Documentation/gitk.txt > @@ -63,10 +63,10 @@ linkgit:git-rev-list[1] for a complete list. > > --merge:: > > - After an attempt to merge stops with conflicts, show the commits on > - the history between two branches (i.e. the HEAD and the MERGE_HEAD) > - that modify the conflicted files and do not exist on all the heads > - being merged. > + Show commits touching conflicted paths in the range `HEAD...$OTHER`, if $OTHER is a placeholder, why not use the placeholder notation instead of a notation that could deceive the reader into thinking that this is an actual environment variable? > + where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, > + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works > + when the index has unmerged entries. > Thanks ``` ## Philippe Blain, 2024-02-13 13:14 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <8384d1dc-b6c4-b853-9bf6-3d7ccee86d12@gmail.com> URL: https://gitlist.dev/e/8384d1dc-b6c4-b853-9bf6-3d7ccee86d12%40gmail.com In-Reply-To: <7a2a0ed5-f9dc-42dd-886b-457641b9bc79@gmail.com> ``` Hi Jean-Nöel, Le 2024-02-13 à 03:33, Jean-Noël Avila a écrit : > Le 11/02/2024 à 00:35, Philippe Blain a écrit : >> From: Michael Lohmann >> >> >> diff --git a/Documentation/gitk.txt b/Documentation/gitk.txt >> index c2213bb77b..80ff4e149a 100644 >> --- a/Documentation/gitk.txt >> +++ b/Documentation/gitk.txt >> @@ -63,10 +63,10 @@ linkgit:git-rev-list[1] for a complete list. >>     --merge:: >>   -    After an attempt to merge stops with conflicts, show the commits on >> -    the history between two branches (i.e. the HEAD and the MERGE_HEAD) >> -    that modify the conflicted files and do not exist on all the heads >> -    being merged. >> +    Show commits touching conflicted paths in the range `HEAD...$OTHER`, > > if $OTHER is a placeholder, why not use the placeholder notation > instead of a notation that could deceive the reader into thinking that > this is an actual environment variable? Good point, I'll make that change. Thanks! Philippe. ``` ## Philippe Blain, 2024-02-13 13:27 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <790a3f11-5a8c-42f2-7a35-f2900c0299b4@gmail.com> URL: https://gitlist.dev/e/790a3f11-5a8c-42f2-7a35-f2900c0299b4%40gmail.com In-Reply-To: ``` Hi Phillip, Le 2024-02-12 à 06:02, Phillip Wood a écrit : > Hi Philippe > > On 10/02/2024 23:35, Philippe Blain wrote: >> From: Michael Lohmann >> >> 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], >> 2006-07-03) to show commits touching conflicted files in the range >> HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document >> rev-list's option --merge, 2006-08-04). >> >> It can be useful to look at the commit history to understand what lead >> to merge conflicts also for other mergy operations besides merges, like >> cherry-pick, revert and rebase. >> >> For rebases, an interesting range to look at is HEAD...REBASE_HEAD, >> since the conflicts are usually caused by how the code changed >> differently on HEAD since REBASE_HEAD forked from it. >> >> For cherry-picks and revert, it is less clear that >> HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting >> ranges, since these commands are about applying or unapplying a single >> (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts >> encountered during these operations can indeed be caused by changes >> introduced in preceding commits on both sides of the history. > > I tend to think that there isn't much difference between rebase and cherry-pick here - they are both cherry-picking commits and it is perfectly possible to rebase a branch onto an unrelated upstream. The important part for me is that we're showing these commits because even though they aren't part of the 3-way merge they are relevant for investigating where any merge conflicts come from. > > For revert I'd argue that the only sane use is reverting an ancestor of HEAD but maybe I'm missing something. In that case REVERT_HEAD...HEAD is the same as REVERT_HEAD..HEAD so it shows the changes since the commit that is being reverted which will be the ones causing the conflict. Thanks, I can rework the wording from that angle. >> Adjust the code in prepare_show_merge so it constructs the range >> HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, >> REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, >> so keep REBASE_HEAD last since the three other operations can be >> performed during a rebase. Note also that in the uncommon case where >> $OTHER and HEAD do not share a common ancestor, this will show the >> complete histories of both sides since their root commits, which is the >> same behaviour as currently happens in that case for HEAD and >> MERGE_HEAD. >> >> Adjust the documentation of this option accordingly. > > Thanks for the comprehensive commit message. > >> diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt >> index 2bf239ff03..5b4672c346 100644 >> --- a/Documentation/rev-list-options.txt >> +++ b/Documentation/rev-list-options.txt >> @@ -341,8 +341,10 @@ See also linkgit:git-reflog[1]. >>   Under `--pretty=reference`, this information will not be shown at all. >>     --merge:: >> -    After a failed merge, show refs that touch files having a >> -    conflict and don't exist on all heads to merge. >> +    Show commits touching conflicted paths in the range `HEAD...$OTHER`, >> +    where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, >> +    `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works >> +    when the index has unmerged entries. > > Do you know what "and don't exist on all heads to merge" in the original is referring to? The new text doesn't mention anything that sounds like that but I don't understand what the original was trying to say. Yes, it took me a while to understand what that meant. I think it is simply describing the range of commits shown. If we substitute "refs" for "commits" and switch the order of the sentence, it reads: After a failed merge, show commits that don't exist on all heads to merge and that touch files having a conflict. So it's just describing (a bit awkwardly) the HEAD...MERGE_HEAD range. > It might be worth adding a sentence explaining when this option is useful. > >     This option can be used to show the commits that are relevant >     when resolving conflicts from a 3-way merge > > or something like that. Nice idea, I'll add that. > >>   --boundary:: >>       Output excluded boundary commits. Boundary commits are >> diff --git a/revision.c b/revision.c >> index aa4c4dc778..36dc2f94f7 100644 >> --- a/revision.c >> +++ b/revision.c >> @@ -1961,11 +1961,31 @@ static void add_pending_commit_list(struct rev_info *revs, >>       } >>   } >>   +static const char *lookup_other_head(struct object_id *oid) >> +{ >> +    int i; >> +    static const char *const other_head[] = { >> +        "MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD" >> +    }; >> + >> +    for (i = 0; i < ARRAY_SIZE(other_head); i++) >> +        if (!read_ref_full(other_head[i], >> +                RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, >> +                oid, NULL)) { >> +            if (is_null_oid(oid)) >> +                die("%s is a symbolic ref???", other_head[i]); > > This would benefit from being translated and I think one '?' would suffice (I'm not sure we even need that - are there other possible causes of a null oid here?) This bit was suggested by Junio upthread in . I'm not sure if the are other causes of null oid, as I don't know well this part of the code. I agree that a single '?' would be enough, but I'm not sure about marking this for translation, I think maybe this situation would be best handled with BUG() ? >> +            return other_head[i]; >> +        } >> + >> +    die("--merge without MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD?"); > > This is not a question and would also benefit from translation. It might be more helpful to say that "--merge" requires one of those pseudorefs. Yes, I agree. I'll tweak that. > Thanks for pick this series up and polishing it > > Phillip > Thanks, Philippe. ``` ## Phillip Wood, 2024-02-14 11:02 Subject: Re: [PATCH v4 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <568f9c07-0b2c-4d4f-9d35-aeeb6e1e29c4@gmail.com> URL: https://gitlist.dev/e/568f9c07-0b2c-4d4f-9d35-aeeb6e1e29c4%40gmail.com In-Reply-To: <790a3f11-5a8c-42f2-7a35-f2900c0299b4@gmail.com> ``` Hi Philippe On 13/02/2024 13:27, Philippe Blain wrote: > Le 2024-02-12 à 06:02, Phillip Wood a écrit : >> Hi Philippe >> On 10/02/2024 23:35, Philippe Blain wrote: >>> From: Michael Lohmann >>> diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt >>> index 2bf239ff03..5b4672c346 100644 >>> --- a/Documentation/rev-list-options.txt >>> +++ b/Documentation/rev-list-options.txt >>> @@ -341,8 +341,10 @@ See also linkgit:git-reflog[1]. >>>   Under `--pretty=reference`, this information will not be shown at all. >>>     --merge:: >>> -    After a failed merge, show refs that touch files having a >>> -    conflict and don't exist on all heads to merge. >>> +    Show commits touching conflicted paths in the range `HEAD...$OTHER`, >>> +    where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, >>> +    `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works >>> +    when the index has unmerged entries. >> >> Do you know what "and don't exist on all heads to merge" in the original > is referring to? The new text doesn't mention anything that sounds like >that but I don't understand what the original was trying to say. > > Yes, it took me a while to understand what that meant. I think it is simply > describing the range of commits shown. If we substitute "refs" for "commits" > and switch the order of the sentence, it reads: > > After a failed merge, show commits that don't exist on all heads to merge > and that touch files having a conflict. > > So it's just describing (a bit awkwardly) the HEAD...MERGE_HEAD range. Ah, that makes sense, thanks for explaining >>> +    for (i = 0; i < ARRAY_SIZE(other_head); i++) >>> +        if (!read_ref_full(other_head[i], >>> +                RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, >>> +                oid, NULL)) { >>> +            if (is_null_oid(oid)) >>> +                die("%s is a symbolic ref???", other_head[i]); >> >> This would benefit from being translated and I think one '?' would suffice >> (I'm not sure we even need that - are there other possible causes of a null >> oid here?) > > This bit was suggested by Junio upthread in . > I'm not sure if the are other causes of null oid, as I don't know well this > part of the code. > I agree that a single '?' would be enough, but I'm not sure about marking > this for translation, I think maybe this situation would be best handled with > BUG() ? I think it would be a bug for git to create MERGE_HEAD as a symbolic ref but when we read MERGE_HEAD and find it is a symbolic ref we don't know if git created it or some third-party script so I think we should just report an error. Best Wishes Phillip ``` ## Philippe Blain, 2024-02-25 21:56 Subject: [PATCH v5 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d@gmail.com> URL: https://gitlist.dev/e/20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d%40gmail.com In-Reply-To: <20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v4-0-3bc9e62808f4@gmail.com> ``` Changes in v5: - Marked error messages for translation and tweaked them as suggested by Phillip - Reworded the message of 2/2 as suggested by Phillip - Removed the change to gitk's doc in 2/2 as pointed out by Johannes - Fixed the trailers in 2/2 - Improved the doc in 2/2 as suggested by Phillip and Jean-Noël Changes in v4: - Added a commit message for 2/2 detailing the use case and summarizing the discussion in the thread - Adjusted the documentation of the option --- Michael Lohmann (2): revision: ensure MERGE_HEAD is a ref in prepare_show_merge revision: implement `git log --merge` also for rebase/cherry-pick/revert Documentation/rev-list-options.txt | 7 +++++-- revision.c | 27 +++++++++++++++++++++++---- 2 files changed, 28 insertions(+), 6 deletions(-) --- base-commit: 186b115d3062e6230ee296d1ddaa0c4b72a464b5 change-id: 20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-05bd8e8797db Range-diff versus v4: 1: 37405be1a3 ! 1: c9536431d1 revision: ensure MERGE_HEAD is a ref in prepare_show_merge @@ Commit message Helped-by: Junio C Hamano Signed-off-by: Michael Lohmann Signed-off-by: Junio C Hamano + Signed-off-by: Philippe Blain ## revision.c ## @@ revision.c: static void prepare_show_merge(struct rev_info *revs) @@ revision.c: static void prepare_show_merge(struct rev_info *revs) + &oid, NULL)) die("--merge without MERGE_HEAD?"); + if (is_null_oid(&oid)) -+ die("MERGE_HEAD is a symbolic ref???"); ++ die(_("MERGE_HEAD is a symbolic ref?")); other = lookup_commit_or_die(&oid, "MERGE_HEAD"); add_pending_object(revs, &head->object, "HEAD"); add_pending_object(revs, &other->object, "MERGE_HEAD"); 2: 6ac1608809 ! 2: 1641c4be81 revision: implement `git log --merge` also for rebase/cherry-pick/revert @@ Commit message to merge conflicts also for other mergy operations besides merges, like cherry-pick, revert and rebase. - For rebases, an interesting range to look at is HEAD...REBASE_HEAD, - since the conflicts are usually caused by how the code changed - differently on HEAD since REBASE_HEAD forked from it. + For rebases and cherry-picks, an interesting range to look at is + HEAD...{REBASE_HEAD,CHERRY_PICK_HEAD}, since even if all the commits + included in that range are not directly part of the 3-way merge, + conflicts encountered during these operations can indeed be caused by + changes introduced in preceding commits on both sides of the history. - For cherry-picks and revert, it is less clear that - HEAD...CHERRY_PICK_HEAD and HEAD...REVERT_HEAD are indeed interesting - ranges, since these commands are about applying or unapplying a single - (or a few, for cherry-pick) commit(s) on top of HEAD. However, conflicts - encountered during these operations can indeed be caused by changes - introduced in preceding commits on both sides of the history. + For revert, as we are (most likely) reversing changes from a previous + commit, an appropriate range is REVERT_HEAD..HEAD, which is equivalent + to REVERT_HEAD...HEAD and to HEAD...REVERT_HEAD, if we keep HEAD and its + parents on the left side of the range. - Adjust the code in prepare_show_merge so it constructs the range - HEAD...$OTHER for each of OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, - REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, - so keep REBASE_HEAD last since the three other operations can be - performed during a rebase. Note also that in the uncommon case where - $OTHER and HEAD do not share a common ancestor, this will show the - complete histories of both sides since their root commits, which is the - same behaviour as currently happens in that case for HEAD and - MERGE_HEAD. + As such, adjust the code in prepare_show_merge so it constructs the + range HEAD...$OTHER for OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD + or REBASE_HEAD}. Note that we try these pseudorefs in order, so keep + REBASE_HEAD last since the three other operations can be performed + during a rebase. Note also that in the uncommon case where $OTHER and + HEAD do not share a common ancestor, this will show the complete + histories of both sides since their root commits, which is the same + behaviour as currently happens in that case for HEAD and MERGE_HEAD. Adjust the documentation of this option accordingly. - Co-authored-by: Philippe Blain Co-authored-by: Johannes Sixt - Signed-off-by: Philippe Blain + Co-authored-by: Philippe Blain Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano - - ## Documentation/gitk.txt ## -@@ Documentation/gitk.txt: linkgit:git-rev-list[1] for a complete list. - - --merge:: - -- After an attempt to merge stops with conflicts, show the commits on -- the history between two branches (i.e. the HEAD and the MERGE_HEAD) -- that modify the conflicted files and do not exist on all the heads -- being merged. -+ Show commits touching conflicted paths in the range `HEAD...$OTHER`, -+ where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, -+ `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works -+ when the index has unmerged entries. - - --left-right:: - + Signed-off-by: Philippe Blain ## Documentation/rev-list-options.txt ## @@ Documentation/rev-list-options.txt: See also linkgit:git-reflog[1]. @@ Documentation/rev-list-options.txt: See also linkgit:git-reflog[1]. --merge:: - After a failed merge, show refs that touch files having a - conflict and don't exist on all heads to merge. -+ Show commits touching conflicted paths in the range `HEAD...$OTHER`, -+ where `$OTHER` is the first existing pseudoref in `MERGE_HEAD`, ++ Show commits touching conflicted paths in the range `HEAD...`, ++ where `` is the first existing pseudoref in `MERGE_HEAD`, + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works -+ when the index has unmerged entries. ++ when the index has unmerged entries. This option can be used to show ++ relevant commits when resolving conflicts from a 3-way merge. --boundary:: Output excluded boundary commits. Boundary commits are @@ revision.c: static void add_pending_commit_list(struct rev_info *revs, + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + oid, NULL)) { + if (is_null_oid(oid)) -+ die("%s is a symbolic ref???", other_head[i]); ++ die(_("%s is a symbolic ref?"), other_head[i]); + return other_head[i]; + } + -+ die("--merge without MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD?"); ++ die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD")); +} + static void prepare_show_merge(struct rev_info *revs) @@ revision.c: static void prepare_show_merge(struct rev_info *revs) - &oid, NULL)) - die("--merge without MERGE_HEAD?"); - if (is_null_oid(&oid)) -- die("MERGE_HEAD is a symbolic ref???"); +- die(_("MERGE_HEAD is a symbolic ref?")); - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); + other_name = lookup_other_head(&oid); + other = lookup_commit_or_die(&oid, other_name); ``` ## Philippe Blain, 2024-02-25 21:56 Subject: [PATCH v5 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge Message-ID: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-1-af1ef2d9e44d@gmail.com> URL: https://gitlist.dev/e/20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-1-af1ef2d9e44d%40gmail.com In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d@gmail.com> ``` From: Michael Lohmann This is done to (1) ensure MERGE_HEAD is a ref, (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() (3) error out when MERGE_HEAD is a symref. Helped-by: Junio C Hamano Signed-off-by: Michael Lohmann Signed-off-by: Junio C Hamano Signed-off-by: Philippe Blain --- revision.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/revision.c b/revision.c index 2424c9bd67..ee26988cc6 100644 --- a/revision.c +++ b/revision.c @@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs) 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)) + if (read_ref_full("MERGE_HEAD", + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + &oid, NULL)) die("--merge without MERGE_HEAD?"); + if (is_null_oid(&oid)) + die(_("MERGE_HEAD is a symbolic ref?")); other = lookup_commit_or_die(&oid, "MERGE_HEAD"); add_pending_object(revs, &head->object, "HEAD"); add_pending_object(revs, &other->object, "MERGE_HEAD"); -- 2.39.1 ``` ## Philippe Blain, 2024-02-25 21:56 Subject: [PATCH v5 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-2-af1ef2d9e44d@gmail.com> URL: https://gitlist.dev/e/20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-2-af1ef2d9e44d%40gmail.com In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d@gmail.com> ``` From: Michael Lohmann 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], 2006-07-03) to show commits touching conflicted files in the range HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document rev-list's option --merge, 2006-08-04). It can be useful to look at the commit history to understand what lead to merge conflicts also for other mergy operations besides merges, like cherry-pick, revert and rebase. For rebases and cherry-picks, an interesting range to look at is HEAD...{REBASE_HEAD,CHERRY_PICK_HEAD}, since even if all the commits included in that range are not directly part of the 3-way merge, conflicts encountered during these operations can indeed be caused by changes introduced in preceding commits on both sides of the history. For revert, as we are (most likely) reversing changes from a previous commit, an appropriate range is REVERT_HEAD..HEAD, which is equivalent to REVERT_HEAD...HEAD and to HEAD...REVERT_HEAD, if we keep HEAD and its parents on the left side of the range. As such, adjust the code in prepare_show_merge so it constructs the range HEAD...$OTHER for OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, so keep REBASE_HEAD last since the three other operations can be performed during a rebase. Note also that in the uncommon case where $OTHER and HEAD do not share a common ancestor, this will show the complete histories of both sides since their root commits, which is the same behaviour as currently happens in that case for HEAD and MERGE_HEAD. Adjust the documentation of this option accordingly. Co-authored-by: Johannes Sixt Co-authored-by: Philippe Blain Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano Signed-off-by: Philippe Blain --- Documentation/rev-list-options.txt | 7 +++++-- revision.c | 31 +++++++++++++++++++++++-------- 2 files changed, 28 insertions(+), 10 deletions(-) diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index 2bf239ff03..9ce7a5eedc 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -341,8 +341,11 @@ See also linkgit:git-reflog[1]. Under `--pretty=reference`, this information will not be shown at all. --merge:: - After a failed merge, show refs that touch files having a - conflict and don't exist on all heads to merge. + Show commits touching conflicted paths in the range `HEAD...`, + where `` is the first existing pseudoref in `MERGE_HEAD`, + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works + when the index has unmerged entries. This option can be used to show + relevant commits when resolving conflicts from a 3-way merge. --boundary:: Output excluded boundary commits. Boundary commits are diff --git a/revision.c b/revision.c index ee26988cc6..a90a6f861b 100644 --- a/revision.c +++ b/revision.c @@ -1961,11 +1961,31 @@ static void add_pending_commit_list(struct rev_info *revs, } } +static const char *lookup_other_head(struct object_id *oid) +{ + int i; + static const char *const other_head[] = { + "MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD" + }; + + for (i = 0; i < ARRAY_SIZE(other_head); i++) + if (!read_ref_full(other_head[i], + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + oid, NULL)) { + if (is_null_oid(oid)) + die(_("%s is a symbolic ref?"), other_head[i]); + return other_head[i]; + } + + die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD")); +} + static void prepare_show_merge(struct rev_info *revs) { struct commit_list *bases; struct commit *head, *other; struct object_id oid; + const char *other_name; const char **prune = NULL; int i, prune_num = 1; /* counting terminating NULL */ struct index_state *istate = revs->repo->index; @@ -1973,15 +1993,10 @@ static void prepare_show_merge(struct rev_info *revs) if (repo_get_oid(the_repository, "HEAD", &oid)) die("--merge without HEAD?"); head = lookup_commit_or_die(&oid, "HEAD"); - if (read_ref_full("MERGE_HEAD", - RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, - &oid, NULL)) - die("--merge without MERGE_HEAD?"); - if (is_null_oid(&oid)) - die(_("MERGE_HEAD is a symbolic ref?")); - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); + other_name = lookup_other_head(&oid); + other = lookup_commit_or_die(&oid, other_name); add_pending_object(revs, &head->object, "HEAD"); - add_pending_object(revs, &other->object, "MERGE_HEAD"); + add_pending_object(revs, &other->object, other_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); -- 2.39.1 ``` ## Junio C Hamano, 2024-02-26 04:35 Subject: Re: [PATCH v5 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/xmqqa5nnj10v.fsf%40gitster.g In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-2-af1ef2d9e44d@gmail.com> ``` Philippe Blain writes: > + for (i = 0; i < ARRAY_SIZE(other_head); i++) > + if (!read_ref_full(other_head[i], > + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, > + oid, NULL)) { > + if (is_null_oid(oid)) > + die(_("%s is a symbolic ref?"), other_head[i]); > + return other_head[i]; > + } > + > + die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD")); > +} Just a minor nit, but reacting to recent "passive-aggressive" message change in another thread, perhaps we should stop asking a rhetorical question like the new message and instead state what we detected and what we consider is an error condition as a fact in them. The last die() in the above helper function used to be such a rhetorical question "--merge without HEAD?" but now it reads much better. The one about symbolic ref is new in this series, and we can avoid making it rhetorical from the get go. Perhaps "%s exists but it is a symbolic ref" or something? ``` ## Jean-Noël Avila, 2024-02-26 17:22 Subject: Re: [PATCH v5 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge Message-ID: URL: https://gitlist.dev/e/c46a0a4f-63dc-404a-8ee2-64a34f474c5f%40gmail.com In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-1-af1ef2d9e44d@gmail.com> ``` Hello, Le 25/02/2024 à 22:56, Philippe Blain a écrit : > From: Michael Lohmann > > This is done to > (1) ensure MERGE_HEAD is a ref, > (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() > (3) error out when MERGE_HEAD is a symref. > > Helped-by: Junio C Hamano > Signed-off-by: Michael Lohmann > Signed-off-by: Junio C Hamano > Signed-off-by: Philippe Blain > --- > revision.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/revision.c b/revision.c > index 2424c9bd67..ee26988cc6 100644 > --- a/revision.c > +++ b/revision.c > @@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs) > 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)) > + if (read_ref_full("MERGE_HEAD", > + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, > + &oid, NULL)) > die("--merge without MERGE_HEAD?"); > + if (is_null_oid(&oid)) > + die(_("MERGE_HEAD is a symbolic ref?")); Following the thread about being less passive-aggressive, maybe this could be rephrased in an assertive mood. By the way, this string is translatable, but not the one 2 lines above. What is the policy around translation? > other = lookup_commit_or_die(&oid, "MERGE_HEAD"); > add_pending_object(revs, &head->object, "HEAD"); > add_pending_object(revs, &other->object, "MERGE_HEAD"); > Thanks. ``` ## Philippe Blain, 2024-02-26 17:43 Subject: Re: [PATCH v5 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/d60ba27a-ac65-842a-9efe-a163480363d5%40gmail.com In-Reply-To: ``` Hi Junio, Le 2024-02-25 à 23:35, Junio C Hamano a écrit : > Philippe Blain writes: > >> + for (i = 0; i < ARRAY_SIZE(other_head); i++) >> + if (!read_ref_full(other_head[i], >> + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, >> + oid, NULL)) { >> + if (is_null_oid(oid)) >> + die(_("%s is a symbolic ref?"), other_head[i]); >> + return other_head[i]; >> + } >> + >> + die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD")); >> +} > > Just a minor nit, but reacting to recent "passive-aggressive" > message change in another thread, perhaps we should stop asking a > rhetorical question like the new message and instead state what we > detected and what we consider is an error condition as a fact in > them. > > The last die() in the above helper function used to be such a > rhetorical question "--merge without HEAD?" but now it reads much > better. The one about symbolic ref is new in this series, and we > can avoid making it rhetorical from the get go. Perhaps "%s exists > but it is a symbolic ref" or something? Ok, I can make that change. I agree we should maybe keep these rethorical questions to 'BUG' calls... Thanks, Philippe. ``` ## Philippe Blain, 2024-02-26 17:54 Subject: Re: [PATCH v5 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge Message-ID: <13c882d4-8f61-1ea5-8949-fdde16bcfc5b@gmail.com> URL: https://gitlist.dev/e/13c882d4-8f61-1ea5-8949-fdde16bcfc5b%40gmail.com In-Reply-To: ``` Hi Jean-Noël, Le 2024-02-26 à 12:22, Jean-Noël Avila a écrit : > Hello, > > Le 25/02/2024 à 22:56, Philippe Blain a écrit : >> From: Michael Lohmann >> >> This is done to >> (1) ensure MERGE_HEAD is a ref, >> (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() >> (3) error out when MERGE_HEAD is a symref. >> >> Helped-by: Junio C Hamano >> Signed-off-by: Michael Lohmann >> Signed-off-by: Junio C Hamano >> Signed-off-by: Philippe Blain >> --- >> revision.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/revision.c b/revision.c >> index 2424c9bd67..ee26988cc6 100644 >> --- a/revision.c >> +++ b/revision.c >> @@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs) >> 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)) >> + if (read_ref_full("MERGE_HEAD", >> + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, >> + &oid, NULL)) >> die("--merge without MERGE_HEAD?"); >> + if (is_null_oid(&oid)) >> + die(_("MERGE_HEAD is a symbolic ref?")); > > Following the thread about being less passive-aggressive, maybe this > could be rephrased in an assertive mood. Yes, Junio suggested the same in . > > By the way, this string is translatable, but not the one 2 lines above. > What is the policy around translation? My understanding is that new error messages should be translated, but here the patch is not touching the message "--merge without HEAD?" so I would think it is OK to avoid changing these lines to mark it for translation. But, I could make that change in a preparatory patch (and rephrase it at the same time). Thanks, Philippe. ``` ## Phillip Wood, 2024-02-27 14:00 Subject: Re: [PATCH v5 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/ff5a3954-4e7a-42b7-988e-f306b45918bf%40gmail.com In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d@gmail.com> ``` On 25/02/2024 21:56, Philippe Blain wrote: > Changes in v5: > - Marked error messages for translation and tweaked them as suggested by Phillip > - Reworded the message of 2/2 as suggested by Phillip > - Removed the change to gitk's doc in 2/2 as pointed out by Johannes > - Fixed the trailers in 2/2 > - Improved the doc in 2/2 as suggested by Phillip and Jean-Noël These changes look good, thanks for making them. I agree with the other reviewers that it would be nice to improve the wording of the error message when we find a symbolic ref. Everything else looks good to me. Thanks Phillip ``` ## Junio C Hamano, 2024-02-27 18:30 Subject: Re: [PATCH v5 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: URL: https://gitlist.dev/e/xmqqmsrlsqty.fsf%40gitster.g In-Reply-To: ``` Phillip Wood writes: > On 25/02/2024 21:56, Philippe Blain wrote: >> Changes in v5: >> - Marked error messages for translation and tweaked them as suggested by Phillip >> - Reworded the message of 2/2 as suggested by Phillip >> - Removed the change to gitk's doc in 2/2 as pointed out by Johannes >> - Fixed the trailers in 2/2 >> - Improved the doc in 2/2 as suggested by Phillip and Jean-Noël > > These changes look good, thanks for making them. I agree with the > other reviewers that it would be nice to improve the wording of the > error message when we find a symbolic ref. Everything else looks good > to me. > > Thanks > > Phillip Thanks for a review. Queued. ``` ## Philippe Blain, 2024-02-28 13:54 Subject: [PATCH v6 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-0-8ec34c052b39@gmail.com> URL: https://gitlist.dev/e/20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-0-8ec34c052b39%40gmail.com In-Reply-To: <20240225-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v5-0-af1ef2d9e44d@gmail.com> ``` Changes in v6: - Changed the error message added in 1/2 and adjusted in 2/2 to avoid a rhetorical question Changes in v5: - Marked error messages for translation and tweaked them as suggested by Phillip - Reworded the message of 2/2 as suggested by Phillip - Removed the change to gitk's doc in 2/2 as pointed out by Johannes - Fixed the trailers in 2/2 - Improved the doc in 2/2 as suggested by Phillip and Jean-Noël Changes in v4: - Added a commit message for 2/2 detailing the use case and summarizing the discussion in the thread - Adjusted the documentation of the option --- Michael Lohmann (2): revision: ensure MERGE_HEAD is a ref in prepare_show_merge revision: implement `git log --merge` also for rebase/cherry-pick/revert Documentation/rev-list-options.txt | 7 +++++-- revision.c | 27 +++++++++++++++++++++++---- 2 files changed, 28 insertions(+), 6 deletions(-) --- base-commit: 3c2a3fdc388747b9eaf4a4a4f2035c1c9ddb26d0 change-id: 20240210-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-05bd8e8797db Range-diff versus v5: 1: c9536431d1 ! 1: 363657561c revision: ensure MERGE_HEAD is a ref in prepare_show_merge @@ Commit message (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() (3) error out when MERGE_HEAD is a symref. + Note that we avoid marking the new error message for translation as it + will be done in the next commit when the message is generalized to other + special refs. + Helped-by: Junio C Hamano Signed-off-by: Michael Lohmann Signed-off-by: Junio C Hamano @@ revision.c: static void prepare_show_merge(struct rev_info *revs) + &oid, NULL)) die("--merge without MERGE_HEAD?"); + if (is_null_oid(&oid)) -+ die(_("MERGE_HEAD is a symbolic ref?")); ++ die(_("MERGE_HEAD exists but is a symbolic ref")); other = lookup_commit_or_die(&oid, "MERGE_HEAD"); add_pending_object(revs, &head->object, "HEAD"); add_pending_object(revs, &other->object, "MERGE_HEAD"); 2: 1641c4be81 ! 2: 749abadc04 revision: implement `git log --merge` also for rebase/cherry-pick/revert @@ revision.c: static void add_pending_commit_list(struct rev_info *revs, + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + oid, NULL)) { + if (is_null_oid(oid)) -+ die(_("%s is a symbolic ref?"), other_head[i]); ++ die(_("%s exists but is a symbolic ref"), other_head[i]); + return other_head[i]; + } + @@ revision.c: static void prepare_show_merge(struct rev_info *revs) - &oid, NULL)) - die("--merge without MERGE_HEAD?"); - if (is_null_oid(&oid)) -- die(_("MERGE_HEAD is a symbolic ref?")); +- die(_("MERGE_HEAD exists but is a symbolic ref")); - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); + other_name = lookup_other_head(&oid); + other = lookup_commit_or_die(&oid, other_name); ``` ## Philippe Blain, 2024-02-28 13:54 Subject: [PATCH v6 1/2] revision: ensure MERGE_HEAD is a ref in prepare_show_merge Message-ID: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-1-8ec34c052b39@gmail.com> URL: https://gitlist.dev/e/20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-1-8ec34c052b39%40gmail.com In-Reply-To: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-0-8ec34c052b39@gmail.com> ``` From: Michael Lohmann This is done to (1) ensure MERGE_HEAD is a ref, (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() (3) error out when MERGE_HEAD is a symref. Note that we avoid marking the new error message for translation as it will be done in the next commit when the message is generalized to other special refs. Helped-by: Junio C Hamano Signed-off-by: Michael Lohmann Signed-off-by: Junio C Hamano Signed-off-by: Philippe Blain --- revision.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/revision.c b/revision.c index 2424c9bd67..df775f74d0 100644 --- a/revision.c +++ b/revision.c @@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs) 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)) + if (read_ref_full("MERGE_HEAD", + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + &oid, NULL)) die("--merge without MERGE_HEAD?"); + if (is_null_oid(&oid)) + die(_("MERGE_HEAD exists but is a symbolic ref")); other = lookup_commit_or_die(&oid, "MERGE_HEAD"); add_pending_object(revs, &head->object, "HEAD"); add_pending_object(revs, &other->object, "MERGE_HEAD"); -- 2.39.1 ``` ## Philippe Blain, 2024-02-28 13:54 Subject: [PATCH v6 2/2] revision: implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-2-8ec34c052b39@gmail.com> URL: https://gitlist.dev/e/20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-2-8ec34c052b39%40gmail.com In-Reply-To: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-0-8ec34c052b39@gmail.com> ``` From: Michael Lohmann 'git log' learned in ae3e5e1ef2 (git log -p --merge [[--] paths...], 2006-07-03) to show commits touching conflicted files in the range HEAD...MERGE_HEAD, an addition documented in d249b45547 (Document rev-list's option --merge, 2006-08-04). It can be useful to look at the commit history to understand what lead to merge conflicts also for other mergy operations besides merges, like cherry-pick, revert and rebase. For rebases and cherry-picks, an interesting range to look at is HEAD...{REBASE_HEAD,CHERRY_PICK_HEAD}, since even if all the commits included in that range are not directly part of the 3-way merge, conflicts encountered during these operations can indeed be caused by changes introduced in preceding commits on both sides of the history. For revert, as we are (most likely) reversing changes from a previous commit, an appropriate range is REVERT_HEAD..HEAD, which is equivalent to REVERT_HEAD...HEAD and to HEAD...REVERT_HEAD, if we keep HEAD and its parents on the left side of the range. As such, adjust the code in prepare_show_merge so it constructs the range HEAD...$OTHER for OTHER={MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD}. Note that we try these pseudorefs in order, so keep REBASE_HEAD last since the three other operations can be performed during a rebase. Note also that in the uncommon case where $OTHER and HEAD do not share a common ancestor, this will show the complete histories of both sides since their root commits, which is the same behaviour as currently happens in that case for HEAD and MERGE_HEAD. Adjust the documentation of this option accordingly. Co-authored-by: Johannes Sixt Co-authored-by: Philippe Blain Signed-off-by: Michael Lohmann [jc: tweaked in j6t's precedence fix that tries REBASE_HEAD last] Signed-off-by: Junio C Hamano Signed-off-by: Philippe Blain --- Documentation/rev-list-options.txt | 7 +++++-- revision.c | 31 +++++++++++++++++++++++-------- 2 files changed, 28 insertions(+), 10 deletions(-) diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index a583b52c61..29e7b50bcf 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -341,8 +341,11 @@ See also linkgit:git-reflog[1]. Under `--pretty=reference`, this information will not be shown at all. --merge:: - After a failed merge, show refs that touch files having a - conflict and don't exist on all heads to merge. + Show commits touching conflicted paths in the range `HEAD...`, + where `` is the first existing pseudoref in `MERGE_HEAD`, + `CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works + when the index has unmerged entries. This option can be used to show + relevant commits when resolving conflicts from a 3-way merge. --boundary:: Output excluded boundary commits. Boundary commits are diff --git a/revision.c b/revision.c index df775f74d0..d2ebdd045a 100644 --- a/revision.c +++ b/revision.c @@ -1961,11 +1961,31 @@ static void add_pending_commit_list(struct rev_info *revs, } } +static const char *lookup_other_head(struct object_id *oid) +{ + int i; + static const char *const other_head[] = { + "MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD" + }; + + for (i = 0; i < ARRAY_SIZE(other_head); i++) + if (!read_ref_full(other_head[i], + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + oid, NULL)) { + if (is_null_oid(oid)) + die(_("%s exists but is a symbolic ref"), other_head[i]); + return other_head[i]; + } + + die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD")); +} + static void prepare_show_merge(struct rev_info *revs) { struct commit_list *bases; struct commit *head, *other; struct object_id oid; + const char *other_name; const char **prune = NULL; int i, prune_num = 1; /* counting terminating NULL */ struct index_state *istate = revs->repo->index; @@ -1973,15 +1993,10 @@ static void prepare_show_merge(struct rev_info *revs) if (repo_get_oid(the_repository, "HEAD", &oid)) die("--merge without HEAD?"); head = lookup_commit_or_die(&oid, "HEAD"); - if (read_ref_full("MERGE_HEAD", - RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, - &oid, NULL)) - die("--merge without MERGE_HEAD?"); - if (is_null_oid(&oid)) - die(_("MERGE_HEAD exists but is a symbolic ref")); - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); + other_name = lookup_other_head(&oid); + other = lookup_commit_or_die(&oid, other_name); add_pending_object(revs, &head->object, "HEAD"); - add_pending_object(revs, &other->object, "MERGE_HEAD"); + add_pending_object(revs, &other->object, other_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); -- 2.39.1 ``` ## phillip.wood123@gmail.com, 2024-02-28 14:40 Subject: Re: [PATCH v6 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <3875a0dc-6ef2-4bd3-9852-c180043464c3@gmail.com> URL: https://gitlist.dev/e/3875a0dc-6ef2-4bd3-9852-c180043464c3%40gmail.com In-Reply-To: <20240228-ml-log-merge-with-cherry-pick-and-other-pseudo-heads-v6-0-8ec34c052b39@gmail.com> ``` Hi Philippe On 28/02/2024 13:54, Philippe Blain wrote: > Range-diff versus v5: > > 1: c9536431d1 ! 1: 363657561c revision: ensure MERGE_HEAD is a ref in prepare_show_merge > @@ Commit message > (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() > (3) error out when MERGE_HEAD is a symref. > > + Note that we avoid marking the new error message for translation as it > + will be done in the next commit when the message is generalized to other > + special refs. Looking at the change below, the new message is in fact marked for translation. I don't think this matters (other than the commit message being confusing) as the translators will only see the final version of the massage. > Helped-by: Junio C Hamano > Signed-off-by: Michael Lohmann > Signed-off-by: Junio C Hamano > @@ revision.c: static void prepare_show_merge(struct rev_info *revs) > + &oid, NULL)) > die("--merge without MERGE_HEAD?"); > + if (is_null_oid(&oid)) > -+ die(_("MERGE_HEAD is a symbolic ref?")); > ++ die(_("MERGE_HEAD exists but is a symbolic ref")); The new message is marked with _(...) so will be translated. > other = lookup_commit_or_die(&oid, "MERGE_HEAD"); > add_pending_object(revs, &head->object, "HEAD"); > add_pending_object(revs, &other->object, "MERGE_HEAD"); > 2: 1641c4be81 ! 2: 749abadc04 revision: implement `git log --merge` also for rebase/cherry-pick/revert > @@ revision.c: static void add_pending_commit_list(struct rev_info *revs, > + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, > + oid, NULL)) { > + if (is_null_oid(oid)) > -+ die(_("%s is a symbolic ref?"), other_head[i]); > ++ die(_("%s exists but is a symbolic ref"), other_head[i]); The second patch updates the message and this new version retains the _(...) Best Wishes Phillip > + return other_head[i]; > + } > + > @@ revision.c: static void prepare_show_merge(struct rev_info *revs) > - &oid, NULL)) > - die("--merge without MERGE_HEAD?"); > - if (is_null_oid(&oid)) > -- die(_("MERGE_HEAD is a symbolic ref?")); > +- die(_("MERGE_HEAD exists but is a symbolic ref")); > - other = lookup_commit_or_die(&oid, "MERGE_HEAD"); > + other_name = lookup_other_head(&oid); > + other = lookup_commit_or_die(&oid, other_name); > ``` ## Philippe Blain, 2024-03-02 15:35 Subject: Re: [PATCH v6 0/2] Implement `git log --merge` also for rebase/cherry-pick/revert Message-ID: <7d21027a-3b5d-dcef-7803-ce41be0a948c@gmail.com> URL: https://gitlist.dev/e/7d21027a-3b5d-dcef-7803-ce41be0a948c%40gmail.com In-Reply-To: <3875a0dc-6ef2-4bd3-9852-c180043464c3@gmail.com> ``` Hi Phillip, Le 2024-02-28 à 09:40, phillip.wood123@gmail.com a écrit : > Hi Philippe > > On 28/02/2024 13:54, Philippe Blain wrote: >> Range-diff versus v5: >> >> 1:  c9536431d1 ! 1:  363657561c revision: ensure MERGE_HEAD is a ref in prepare_show_merge >>      @@ Commit message >>           (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref() >>           (3) error out when MERGE_HEAD is a symref. >>            +    Note that we avoid marking the new error message for translation as it >>      +    will be done in the next commit when the message is generalized to other >>      +    special refs. > > Looking at the change below, the new message is in fact marked for translation. I don't think this matters (other than the commit message being confusing) as the translators will only see the final version of the massage. Oops, you are right, I wanted to do what I wrote but ended up marking it also in 1/2. Junio already merged it to next, so I guess it's gonna stay that way. Thanks for your review, Philippe. ```