Re: [PATCH 3/6] sparse-checkout: enable `set` to initialize sparse-checkout mode

[Elijah Newren <newren@gmail.com>]

On Tue, Dec 7, 2021 at 8:43 AM Derrick Stolee <stolee@gmail.com> wrote:
>
> On 12/4/2021 3:00 PM, Elijah Newren via GitGitGadget wrote:
> >  static int sparse_checkout_set(int argc, const char **argv, const char *prefix)
> >  {
> > +     int mode, record_mode;
> > +     const char *default_patterns[] = {"/*", "!/*/"};
>
> My gut reaction is that this array should be NULL terminated.

Sure, I can make that change.

> > +
> >       static struct option builtin_sparse_checkout_set_options[] = {
> > +             OPT_BOOL(0, "cone", &set_opts.cone_mode,
> > +                      N_("initialize the sparse-checkout in cone mode")),
> > +             OPT_BOOL(0, "sparse-index", &set_opts.sparse_index,
> > +                      N_("toggle the use of a sparse index")),
> >               OPT_BOOL(0, "stdin", &set_opts.use_stdin,
> >                        N_("read patterns from standard in")),
> >               OPT_END(),
> > @@ -700,11 +709,52 @@ static int sparse_checkout_set(int argc, const char **argv, const char *prefix)
> >
> >       repo_read_index(the_repository);
> >
> > +     set_opts.cone_mode = -1;
> > +     set_opts.sparse_index = -1;
> > +
> >       argc = parse_options(argc, argv, prefix,
> >                            builtin_sparse_checkout_set_options,
> >                            builtin_sparse_checkout_set_usage,
> >                            PARSE_OPT_KEEP_UNKNOWN);
> >
> > +     /* Determine if we need to record the mode; ensure sparse checkout on */
> > +     record_mode = (set_opts.cone_mode != -1) || !core_apply_sparse_checkout;
> > +     core_apply_sparse_checkout = 1;
> > +
> > +     /* If not specified, use previous definition of cone mode */
> > +     if (set_opts.cone_mode == -1 && core_apply_sparse_checkout)
> > +             set_opts.cone_mode = core_sparse_checkout_cone;
> > +
> > +     /* Set cone/non-cone mode appropriately */
> > +     if (set_opts.cone_mode == 1) {
> > +             mode = MODE_CONE_PATTERNS;
> > +             core_sparse_checkout_cone = 1;
> > +     } else {
> > +             mode = MODE_ALL_PATTERNS;
> > +     }
> > +     if (record_mode && set_config(mode))
> > +             return 1;
>
> I think it is appropriate to still have the init steps before the modification
> of the worktree. I did have a brief pause to think about whether the set_config()
> should be delayed until modify_pattern_list() succeeds.
>
> > +     /* Set sparse-index/non-sparse-index mode if specified */
> > +     if (set_opts.sparse_index >= 0) {
> > +             if (set_sparse_index_config(the_repository, set_opts.sparse_index) < 0)
> > +                     die(_("failed to modify sparse-index config"));
> > +
> > +             /* force an index rewrite */
> > +             repo_read_index(the_repository);
> > +             the_repository->index->updated_workdir = 1;
> > +     }
> > +
> > +     /*
> > +      * Cone mode automatically specifies the toplevel directory.  For
> > +      * non-cone mode, if nothing is specified, manually select just the
> > +      * top-level directory (much as 'init' would do).
> > +      */
> > +     if (!core_sparse_checkout_cone && argc == 0) {
> > +             argv = default_patterns;
> > +             argc = 2;
>
> Perhaps use 'default_patterns_nr' as a constant near the definition of
> 'default_patterns' so these numbers are not so far apart?

Sounds like a good idea; will do.

>
> > +     }
> > +
> >       return modify_pattern_list(argc, argv, set_opts.use_stdin, REPLACE);
> >  }
>
> Thanks,
> -Stolee