Re: Make 'git fsck' complain about non-commit branches

[Junio C Hamano <gitster@pobox.com>]

Linus Torvalds <torvalds@linux-foundation.org> writes:

> Since having non-commits in branches is a no-no, and just means you cannot 
> commit on them, let's make fsck tell you when a branch is bad.
>
> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I think all of the three patches (so far -- do you have more?)
look sane from the Porcelain-plumbing combination point of view,
but I wonder if we should make it more explicit that we are now
moving in the direction that makes plumbing much more aware of
the Porcelain convention.

So far, the plumbing level did not care much about the Porcelain
convention, such as refs/heads and refs/remotes (you seem to
have forgot) are about "branches" and must point at commit
objects.

> ---
>
>  builtin-fsck.c |   13 ++++++++-----
>  1 files changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/builtin-fsck.c b/builtin-fsck.c
> index 8876d34..6fc9525 100644
> --- a/builtin-fsck.c
> +++ b/builtin-fsck.c
> @@ -555,20 +555,23 @@ static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, in
>  	return 0;
>  }
>  
> +static int is_branch(const char *refname)
> +{
> +	return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
> +}
> +
>  static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
>  {
>  	struct object *obj;
>  
> -	obj = lookup_object(sha1);
> +	obj = parse_object(sha1);
>  	if (!obj) {
> -		if (has_sha1_file(sha1)) {
> -			default_refs++;
> -			return 0; /* it is in a pack */
> -		}
>  		error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
>  		/* We'll continue with the rest despite the error.. */
>  		return 0;
>  	}
> +	if (obj->type != OBJ_COMMIT && is_branch(refname))
> +		error("%s: not a commit", refname);
>  	default_refs++;
>  	obj->used = 1;
>  	mark_reachable(obj, REACHABLE);