index_has_changes(): avoid assuming operating on the_index

Modify index_has_changes() to take a struct istate* instead of just
operating on the_index.  This is only a partial conversion, though,
because we call do_diff_cache() which implicitly assumes work is to be
done on the_index.  Ongoing work is being done elsewhere to do the
remainder of the conversion, and thus is not duplicated here.  Instead,
a simple check is put in place until that work is complete.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/cache.h b/cache.h
index 0323853..169c809 100644
--- a/cache.h
+++ b/cache.h
@@ -627,12 +627,13 @@ extern void move_index_extensions(struct index_state *dst, struct index_state *s
 extern int unmerged_index(const struct index_state *);
 
 /**
- * Returns 1 if the index differs from HEAD, 0 otherwise. When on an unborn
- * branch, returns 1 if there are entries in the index, 0 otherwise. If an
- * strbuf is provided, the space-separated list of files that differ will be
- * appended to it.
+ * Returns 1 if istate differs from HEAD, 0 otherwise.  When on an unborn
+ * branch, returns 1 if there are entries in istate, 0 otherwise.  If an
+ * strbuf is provided, the space-separated list of files that differ will
+ * be appended to it.
  */
-extern int index_has_changes(struct strbuf *sb);
+extern int index_has_changes(const struct index_state *istate,
+			     struct strbuf *sb);
 
 extern int verify_path(const char *path, unsigned mode);
 extern int strcmp_offset(const char *s1, const char *s2, size_t *first_change);