[GSOC][RFC] Heed core.bare from template config file when no command line override given, as a microproject.

Hello,

I'm currently an undergrad beginning my journey of contributing to the Git project. I am seeking feedback on doing "Heed core.bare from template config file when no command line override given" described here https://lore.kernel.org/git/5b39c530f2a0edf3b1492fa13a1132d622a0678e.1684218850.git.gitgitgadget@gmail.com/ by Elijah Newren, as a microproject. I would like to know from the community, if the complexity and scope of the project is appropriate for a microproject.

Approach: As described by Elijah in commit message that fixing this cannot be done in the create_default_files() function as it occurs too late. This is because both clone and init have different checks and steps for working with bare flag, like clone creates a new directory [name].git and sets the GIT_DIR_ENVIRONMENT to it (when not provided with an explicit dir name arg), while init sets the GIT_DIR_ENVIRONMENT to the current working directory (when not provided with an dir name arg). Also there are other steps like setting no_checkout in a bare repository in builtin/clone.c. These are all command specific steps which occur in builtin/clone.c and builtin/init-db.c ,before we ever hit the TODO comment via [builtin/clone.c]cmd_clone()->[setup.c]init_db()-> [setup.c]create_default_files().

Therefore, rather than centralizing the code in setup.c and adding a bunch of if-else statements to handle different command specific scenarios related to bare option, I propose to add a check for template file config just after parsing of the flags and args in builtin/init-db.c and builtin/clone.c.

e.g. in builtin/init-db.c :

static int template_bare_config(const char *var, const char *value,
                     const struct config_context *ctx, void *cb)
{
       if(!strcmp(var,"core.bare")) {
             is_bare_repository_cfg = git_config_bool(var, value);
       }
       return 0;
}

int cmd_init_db(int argc, const char **argv, const char *prefix)
{
...
...
       if(is_bare_repository_cfg==-1) {
             if(!template_dir)
                   git_config_get_pathname("init.templateDir",
                                           &template_dir);

             if(template_dir) {
                   const char* template_config_path
                                = xstrfmt("%s/config",
                   struct stat st;

                   if(!stat(template_config_path, &st) &&
                     !S_ISDIR(st.st_mode)) {
                         git_config_from_file(template_bare_cfg,
                                        template_config_path, NULL);
                   }
             }
...
...
       return init_db(git_dir, real_git_dir, template_dir, hash_algo,
                      initial_branch, init_shared_repository, flags);
}

I also wanted to know if the global config files should have an effect in deciding if the repo is bare or not.

Curious to know your thoughts on, if this is the right approach or does it require doing refactoring to bring all the logic in setup.c. Based on your feedback, I can quickly send a patch.

p.s.: Apologies for the weird indenting, due to 70 character limit. consider it just a prototype.

Thanks!