diff.c: remove implicit dependency on the_index

A new variant repo_diff_setup() is added that takes 'struct repository *'
and diff_setup() becomes a thin macro around it that is protected by
NO_THE_REPOSITORY_COMPATIBILITY_MACROS, similar to NO_THE_INDEX_....
The plan is these macros will always be defined for all library files
and the macros are only accessible in builtin/

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/diff.c b/diff.c
index 0848ac65df..1bcc0818df 100644
--- a/diff.c
+++ b/diff.c
@@ -4390,12 +4390,12 @@ static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
 	builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
 }
 
-void diff_setup(struct diff_options *options)
+void repo_diff_setup(struct repository *r, struct diff_options *options)
 {
 	memcpy(options, &default_diff_options, sizeof(*options));
 
 	options->file = stdout;
-	options->repo->index = &the_index;
+	options->repo = r;
 
 	options->abbrev = DEFAULT_ABBREV;
 	options->line_termination = '\n';