Re: [PATCH v2] sequencer: handle rebase-merges for "onto" message

> In order to work correctly, git-rebase --rebase-merges needs to make
> initial todo list with unique labels.
>
> Those unique labels is being handled by employing a hashmap and
> appending an unique number if any duplicate is found.
>
> But, we forget that beside those labels for side branches,
> we also have a special label `onto' for our so-called new-base.
>
> In a special case that any of those labels for side branches named
> `onto', git will run into trouble.
>
> Correct it.
>
> Signed-off-by: Doan Tran Cong Danh <congdanhqx@gmail.com>
> ---

> Sorry for the noise, I forgot to check spelling for v1
>
> And I forgot to delete From line when append to my MUA.
>
> Range-diff against v1:
> 1:  48205889b4 ! 1:  9246beacf2 sequencer: handle rebase-merge for "onto" message
>     @@ Metadata
>      Author: Doan Tran Cong Danh <congdanhqx@gmail.com>
>
>       ## Commit message ##
>     -    sequencer: handle rebase-merge for "onto" message
>     +    sequencer: handle rebase-merges for "onto" message
>
>          In order to work correctly, git-rebase --rebase-merges needs to make
>          initial todo list with unique labels.
>
>          Those unique labels is being handled by employing a hashmap and
>     -    suffixing an unique number if any duplicate is found.
>     +    appending an unique number if any duplicate is found.
>
>     -    But we forgat that beside of those labels for side branches,
>     -    we also make a special label `onto' for our so-called new-base.
>     +    But, we forget that beside those labels for side branches,
>     +    we also have a special label `onto' for our so-called new-base.
>
>          In a special case that any of those labels for side branches named
>          `onto', git will run into trouble.
>
>  sequencer.c              |  5 +++++
>  t/t3430-rebase-merges.sh | 21 +++++++++++++++++++++
>  2 files changed, 26 insertions(+)
>
> diff --git a/sequencer.c b/sequencer.c
> index 350045b1b4..fc81e43f0f 100644
> --- a/sequencer.c
> +++ b/sequencer.c
> @@ -4569,10 +4569,15 @@ static int make_script_with_merges(struct pretty_print_context *pp,
>  	strbuf_init(&state.buf, 32);
>
>  	if (revs->cmdline.nr && (revs->cmdline.rev[0].flags & BOTTOM)) {
> +		struct labels_entry *onto_label_entry;
>  		struct object_id *oid = &revs->cmdline.rev[0].item->oid;
>  		FLEX_ALLOC_STR(entry, string, "onto");
>  		oidcpy(&entry->entry.oid, oid);
>  		oidmap_put(&state.commit2label, entry);
> +
> +		FLEX_ALLOC_STR(onto_label_entry, label, "onto");
> +		hashmap_entry_init(&onto_label_entry->entry, strihash("onto"));
> +		hashmap_add(&state.labels, &onto_label_entry->entry);
>  	}
>
>  	/*
> diff --git a/t/t3430-rebase-merges.sh b/t/t3430-rebase-merges.sh
> index f728aba995..4e2c0ede51 100755
> --- a/t/t3430-rebase-merges.sh
> +++ b/t/t3430-rebase-merges.sh
> @@ -474,4 +474,25 @@ test_expect_success '--rebase-merges with commit that can generate bad character
>  	git rebase --rebase-merges --force-rebase E
>  '
>
> +test_expect_success '--rebase-merges with message matched with onto label' '
> +	git checkout -b onto-label E &&
> +	git merge -m onto G &&
> +	git rebase --rebase-merges --force-rebase E &&
> +	test_cmp_graph <<-\EOF
> +	*   onto
> +	|\
> +	| * G
> +	| * F
> +	* |   E
> +	|\ \
> +	| * | B
> +	* | | D
> +	| |/
> +	|/|
> +	* | C
> +	|/
> +	* A
> +	EOF
> +'
> +
>  test_done
> --
> 2.24.0.10.gc61c3b979f.dirty
>
>