Re: [GSoC] [PATCH] submodule--helper: introduce add-config subcommand

[Atharva Raykar <raykar.ath@gmail.com>]

On 22-Jul-2021, at 17:20, Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote:
> 
> 
> On Thu, Jul 22 2021, Atharva Raykar wrote:
> 
>> +static void config_submodule_in_gitmodules(const char *name, const char *var, const char *value)
>> +{
>> +	char *key;
>> +
>> +	if (!is_writing_gitmodules_ok())
>> +		die(_("please make sure that the .gitmodules file is in the working tree"));
>> +
>> +	key = xstrfmt("submodule.%s.%s", name, var);
>> +	config_set_in_gitmodules_file_gently(key, value);
>> +	free(key);
>> +}
> 
> Just a small point not per-se to do with this patch, but aren't all
> callers of config_set_in_gitmodules_file_gently() wanting to prefix
> thigs with "submodule."? Looks like its API could be simplified a bit
> with that xstrfmt() and free() inside that function.

Yes, you are right, all the callers prefix with "submodule.". Changing
the API to what you suggested, would require some special handling in
'submodule--helper:module_config()', which will be dead code after the
whole series is done, so probably a better time to change it would be
during the cleanup after the conversion.

>> +static void configure_added_submodule(struct add_data *add_data)
>> +{
>> +	char *key, *submod_pathspec = NULL;
>> +	struct child_process add_submod = CHILD_PROCESS_INIT;
>> +	struct child_process add_gitmodules = CHILD_PROCESS_INIT;
>> +	int pathspec_key_exists, activate = 0;
> 
> Usual style is to have different variables on different lines, unless
> they're closely related (like "int i, j"), so "char *key;\n char
> *submod[...]" in this case.

Okay.

>> +
>> +	key = xstrfmt("submodule.%s.url", add_data->sm_name);
>> +	git_config_set_gently(key, add_data->realrepo);
>> +	free(key);
>> +
>> +	add_submod.git_cmd = 1;
>> +	strvec_pushl(&add_submod.args, "add",
>> +		     "--no-warn-embedded-repo", NULL);
>> +	if (add_data->force)
>> +		strvec_push(&add_submod.args, "--force");
>> +	strvec_pushl(&add_submod.args, "--", add_data->sm_path, NULL);
>> +
>> +	if (run_command(&add_submod))
>> +		die(_("Failed to add submodule '%s'"), add_data->sm_path);
>> +
>> +	config_submodule_in_gitmodules(add_data->sm_name, "path", add_data->sm_path);
>> +	config_submodule_in_gitmodules(add_data->sm_name, "url", add_data->repo);
>> +	if (add_data->branch)
>> +		config_submodule_in_gitmodules(add_data->sm_name,
>> +					       "branch", add_data->branch);
>> +
>> +	add_gitmodules.git_cmd = 1;
>> +	strvec_pushl(&add_gitmodules.args,
>> +		     "add", "--force", "--", ".gitmodules", NULL);
>> +
>> +	if (run_command(&add_gitmodules))
>> +		die(_("Failed to register submodule '%s'"), add_data->sm_path);
> 
> Looks good at a glance.
> 
>> +	/*
>> +	 * NEEDSWORK: In a multi-working-tree world this needs to be
>> +	 * set in the per-worktree config.
>> +	 */
> 
> So should we have a failing test for that scenario, or...? (Update: but
> read ahead...)
> 
>> +static int add_config(int argc, const char **argv, const char *prefix)
>> +{
>> +	int force = 0;
>> +	struct add_data add_data = ADD_DATA_INIT;
>> +
>> +	struct option options[] = {
>> +		OPT_STRING('b', "branch", &add_data.branch,
>> +			   N_("branch"),
>> +			   N_("branch of repository to store in "
>> +			      "the submodule configuration")),
>> +		OPT_STRING(0, "url", &add_data.repo,
>> +			   N_("string"),
>> +			   N_("url to clone submodule from")),
>> +		OPT_STRING(0, "resolved-url", &add_data.realrepo,
>> +			   N_("string"),
>> +			   N_("url to clone the submodule from, after it has "
>> +			      "been dereferenced relative to parent's url, "
>> +			      "in the case where <url> is a relative url")),
>> +		OPT_STRING(0, "path", &add_data.sm_path,
>> +			   N_("path"),
>> +			   N_("where the new submodule will be cloned to")),
>> +		OPT_STRING(0, "name", &add_data.sm_name,
>> +			   N_("string"),
>> +			   N_("name of the new submodule")),
>> +		OPT__FORCE(&force, N_("allow adding an otherwise ignored submodule path"),
>> +			   PARSE_OPT_NOCOMPLETE),
>> +		OPT_END()
>> +	};
>> +
>> +	const char *const usage[] = {
>> +		N_("git submodule--helper add-config "
>> +		   "[--force|-f] [--branch|-b <branch>] "
>> +		   "--url <url> --resolved-url <resolved-url> "
>> +		   "--path <path> --name <name>"),
>> +		NULL
>> +	};
> 
> I'd say consider adding this as a "static" earlier in the file, but it's
> an established pattern in this file, so let's keep it.
> 
>> +	argc = parse_options(argc, argv, prefix, options, usage, 0);
> 
> It's fine to omit it for a helper, but we're being non-pedantic about
> checking mandatory options here. Would do it in a "real" built-in, but
> for internal use it's fine.
> 
>> +	if (argc != 0)
> 
> Style: if (!argc)

Will fix.

>> +		usage_with_options(usage, options);
>> +
>> +	add_data.force = !!force;
>> +	configure_added_submodule(&add_data);
>> +
>> +	return 0;
>> +}
>> +
>> #define SUPPORT_SUPER_PREFIX (1<<0)
>> 
>> struct cmd_struct {
>> @@ -2949,6 +3073,7 @@ static struct cmd_struct commands[] = {
>> 	{"name", module_name, 0},
>> 	{"clone", module_clone, 0},
>> 	{"add-clone", add_clone, 0},
>> +	{"add-config", add_config, 0},
>> 	{"update-module-mode", module_update_module_mode, 0},
>> 	{"update-clone", update_clone, 0},
>> 	{"ensure-core-worktree", ensure_core_worktree, 0},
>> diff --git a/git-submodule.sh b/git-submodule.sh
>> index 053daf3724..f713cb113c 100755
>> --- a/git-submodule.sh
>> +++ b/git-submodule.sh
>> @@ -242,33 +242,7 @@ cmd_add()
>> 	fi
>> 
>> 	git submodule--helper add-clone ${GIT_QUIET:+--quiet} ${force:+"--force"} ${progress:+"--progress"} ${branch:+--branch "$branch"} --prefix "$wt_prefix" --path "$sm_path" --name "$sm_name" --url "$realrepo" ${reference:+"$reference"} ${dissociate:+"--dissociate"} ${depth:+"$depth"} || exit
>> -	git config submodule."$sm_name".url "$realrepo"
>> -
>> -	git add --no-warn-embedded-repo $force "$sm_path" ||
>> -	die "fatal: $(eval_gettext "Failed to add submodule '\$sm_path'")"
>> -
>> -	git submodule--helper config submodule."$sm_name".path "$sm_path" &&
>> -	git submodule--helper config submodule."$sm_name".url "$repo" &&
>> -	if test -n "$branch"
>> -	then
>> -		git submodule--helper config submodule."$sm_name".branch "$branch"
>> -	fi &&
>> -	git add --force .gitmodules ||
>> -	die "fatal: $(eval_gettext "Failed to register submodule '\$sm_path'")"
>> -
>> -	# NEEDSWORK: In a multi-working-tree world, this needs to be
>> -	# set in the per-worktree config.
> 
> Ah, this is the NEEDSWORK comment, just copied to the C code...
> 
>> -	if git config --get submodule.active >/dev/null
>> -	then
>> -		# If the submodule being adding isn't already covered by the
>> -		# current configured pathspec, set the submodule's active flag
>> -		if ! git submodule--helper is-active "$sm_path"
>> -		then
>> -			git config submodule."$sm_name".active "true"
>> -		fi
>> -	else
>> -		git config submodule."$sm_name".active "true"
>> -	fi
>> +	git submodule--helper add-config ${force:+--force} ${branch:+--branch "$branch"} --url "$repo" --resolved-url "$realrepo" --path "$sm_path" --name "$sm_name"
>> }
>> 
> 
> Very nice to have this simplified.
> 
> Would be good to split this very long line across multiple lines
> though...

I followed the established pattern of not splitting the lines from the
previous conversions ('submodule--helper update-clone' being the
exception in that file).

In this case, I felt it should be fine because a follow-up series that
completes the full conversion will get rid of that line entirely.