Re: [PATCH v3 07/10] submodule: check for unstaged .gitmodules outside of config parsing

[Brandon Williams <bmwill@google.com>]

On 07/31, Stefan Beller wrote:
> On Tue, Jul 18, 2017 at 12:05 PM, Brandon Williams <bmwill@google.com> wrote:
> > Teach 'is_staging_gitmodules_ok()' to be able to determine in the
> > '.gitmodules' file has unstaged changes based on the passed in index
> > instead of relying on a global varible which is set during the
> 
> variable
> 

Will change.

> > submodule-config parsing.
> >
> > Signed-off-by: Brandon Williams <bmwill@google.com>
> > ---
> >  builtin/mv.c |  2 +-
> >  builtin/rm.c |  2 +-
> >  submodule.c  | 32 +++++++++++++++++---------------
> >  submodule.h  |  2 +-
> >  4 files changed, 20 insertions(+), 18 deletions(-)
> >
> > diff --git a/builtin/mv.c b/builtin/mv.c
> > index dcf6736b5..94fbaaa5d 100644
> > --- a/builtin/mv.c
> > +++ b/builtin/mv.c
> > @@ -81,7 +81,7 @@ static void prepare_move_submodule(const char *src, int first,
> >         struct strbuf submodule_dotgit = STRBUF_INIT;
> >         if (!S_ISGITLINK(active_cache[first]->ce_mode))
> >                 die(_("Directory %s is in index and no submodule?"), src);
> > -       if (!is_staging_gitmodules_ok())
> > +       if (!is_staging_gitmodules_ok(&the_index))
> >                 die(_("Please stage your changes to .gitmodules or stash them to proceed"));
> >         strbuf_addf(&submodule_dotgit, "%s/.git", src);
> >         *submodule_gitfile = read_gitfile(submodule_dotgit.buf);
> > diff --git a/builtin/rm.c b/builtin/rm.c
> > index 52826d137..4057e73fa 100644
> > --- a/builtin/rm.c
> > +++ b/builtin/rm.c
> > @@ -286,7 +286,7 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
> >                 list.entry[list.nr].name = xstrdup(ce->name);
> >                 list.entry[list.nr].is_submodule = S_ISGITLINK(ce->ce_mode);
> >                 if (list.entry[list.nr++].is_submodule &&
> > -                   !is_staging_gitmodules_ok())
> > +                   !is_staging_gitmodules_ok(&the_index))
> >                         die (_("Please stage your changes to .gitmodules or stash them to proceed"));
> >         }
> >
> > diff --git a/submodule.c b/submodule.c
> > index b1965290f..46ec04d7c 100644
> > --- a/submodule.c
> > +++ b/submodule.c
> > @@ -37,18 +37,25 @@ static struct oid_array ref_tips_after_fetch;
> >  static int gitmodules_is_unmerged;
> >
> >  /*
> > - * This flag is set if the .gitmodules file had unstaged modifications on
> > - * startup. This must be checked before allowing modifications to the
> > - * .gitmodules file with the intention to stage them later, because when
> > - * continuing we would stage the modifications the user didn't stage herself
> > - * too. That might change in a future version when we learn to stage the
> > - * changes we do ourselves without staging any previous modifications.
> > + * Check if the .gitmodules file has unstaged modifications.  This must be
> > + * checked before allowing modifications to the .gitmodules file with the
> > + * intention to stage them later, because when continuing we would stage the
> > + * modifications the user didn't stage herself too. That might change in a
> > + * future version when we learn to stage the changes we do ourselves without
> > + * staging any previous modifications.
> >   */
> > -static int gitmodules_is_modified;
> > -
> > -int is_staging_gitmodules_ok(void)
> > +int is_staging_gitmodules_ok(const struct index_state *istate)
> >  {
> > -       return !gitmodules_is_modified;
> > +       int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
> > +
> > +       if ((pos >= 0) && (pos < istate->cache_nr)) {
> 
> Why do we need the second check (pos < istate->cache_nr) ?
> 
> I would have assumed the first one suffices,
> it might read better if turned around:
> 
> 
>     if (pos < 0)
>         return 1;
> 
>     return (lstat(GITMODULES_FILE, &st) == 0 &&
>         ce_match_stat(istate->cache[pos], &st, 0) & DATA_CHANGED);
>   }
> 
> > @@ -231,11 +238,6 @@ void gitmodules_config(void)
> >                                     !memcmp(ce->name, ".gitmodules", 11))
> >                                         gitmodules_is_unmerged = 1;
> >                         }
> > -               } else if (pos < active_nr) {
> > -                       struct stat st;
> > -                       if (lstat(".gitmodules", &st) == 0 &&
> > -                           ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
> > -                               gitmodules_is_modified = 1;
> >                 }
> 
> So this is where the check "pos < active_nr" is coming from,
> introduced in 5fee995244 (submodule.c: add .gitmodules staging
> helper functions, 2013-07-30) as well as d4e98b581b (Submodules:
> Don't parse .gitmodules when it contains, merge conflicts, 2011-05-14).
> 
> If I am reading the docs for cache_name_pos correctly, we would
> not need to check for the index exceeding active_cache,
> but checking for the index not being out of bounds seems
> to be wide spread.

I can drop the pos < active_nr requirement.

-- 
Brandon Williams