Subject: Re: [PATCH v4 15/16] bisect: remove Cogito-related code

From: Junio C Hamano <[email-masked]>
Date: Mon, 27 Jun 2022 15:18:21 -0700

"Johannes Schindelin via GitGitGadget" <[email-masked]>
writes:

> As of April 19th, 2007, Cogito was therefore discontinued (see
> https://lore.kernel.org/git/[email-masked]/).
>
> Nevertheless, for almost 15 years after that announcement, Git carried
> special code in `git bisect` to accommodate Cogito.

Good eyes.  Doesn't steps 15 & 16 cover the same theme, though?
IOW, if surviving Cogito users appear after we take this 16-patch
series, would reverting this step the only thing needed if we decide
to accomodate them again (and removal of head-name done in step 16
can still be kept without harming these Cogito users)?  I am wondering
if these should be merged into one patch.

Thanks.

>
> Since it is beyond doubt that there are no more Cogito users, let's
> remove the last remnant of Cogito-accommodating code.
>
> Signed-off-by: Johannes Schindelin <[email-masked]>
> ---
>  builtin/bisect.c | 8 --------
>  1 file changed, 8 deletions(-)

>
> diff --git a/builtin/bisect.c b/builtin/bisect.c
> index 380fef852f3..47103ebf3f2 100644
> --- a/builtin/bisect.c
> +++ b/builtin/bisect.c
> @@ -14,7 +14,6 @@ static GIT_PATH_FUNC(git_path_bisect_expected_rev, "BISECT_EXPECTED_REV")
>  static GIT_PATH_FUNC(git_path_bisect_ancestors_ok, "BISECT_ANCESTORS_OK")
>  static GIT_PATH_FUNC(git_path_bisect_start, "BISECT_START")
>  static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
> -static GIT_PATH_FUNC(git_path_head_name, "head-name")
>  static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
>  static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
>  static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
> @@ -809,13 +808,6 @@ static enum bisect_error bisect_start(struct bisect_terms *terms, const char **a
>  			strbuf_addstr(&start_head, oid_to_hex(&head_oid));
>  		} else if (!get_oid(head, &head_oid) &&
>  			   skip_prefix(head, "refs/heads/", &head)) {
> -			/*
> -			 * This error message should only be triggered by
> -			 * cogito usage, and cogito users should understand
> -			 * it relates to cg-seek.
> -			 */
> -			if (!is_empty_or_missing_file(git_path_head_name()))
> -				return error(_("won't bisect on cg-seek'ed tree"));
>  			strbuf_addstr(&start_head, head);
>  		} else {
>  			return error(_("bad HEAD - strange symbolic ref"));