pathspec: add flag to indicate operation without repository

A following change will add support for pathspecs to the git diff
--no-index command. This mode of git diff does not load any repository.

Add a new PATHSPEC_NO_REPOSITORY flag indicating that we're parsing
pathspecs without a repository.

Both PATHSPEC_ATTR and PATHSPEC_FROMTOP require a repository to
function. Thus, verify that both of these are set in magic_mask to
ensure they won't be accepted when PATHSPEC_NO_REPOSITORY is set.

Check PATHSPEC_NO_REPOSITORY when warning about paths outside the
directory tree. When the flag is set, do not look for a git repository
when generating the warning message.

Finally, add a BUG in match_pathspec_item if the istate is NULL but the
pathspec has PATHSPEC_ATTR set. Callers which support PATHSPEC_ATTR
should always pass a valid istate, and callers which don't pass a valid
istate should have set PATHSPEC_ATTR in the magic_mask field to disable
support for attribute-based pathspecs.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/dir.c b/dir.c
index 86eb77b82a..c8c869faed 100644
--- a/dir.c
+++ b/dir.c
@@ -397,9 +397,12 @@ static int match_pathspec_item(struct index_state *istate,
 	    strncmp(item->match, name - prefix, item->prefix))
 		return 0;
 
-	if (item->attr_match_nr &&
-	    !match_pathspec_attrs(istate, name - prefix, namelen + prefix, item))
-		return 0;
+	if (item->attr_match_nr) {
+		if (!istate)
+			BUG("magic PATHSPEC_ATTR requires an index");
+		if (!match_pathspec_attrs(istate, name - prefix, namelen + prefix, item))
+			return 0;
+	}
 
 	/* If the match was just the prefix, we matched */
 	if (!*match)