Merge branch 'jc/diff-index-quick-exit-early' into maint

* jc/diff-index-quick-exit-early:
  diff-index --quiet: learn the "stop feeding the backend early" logic

Conflicts:
	unpack-trees.h

diff-lib.c

@@ -433,8 +433,13 @@ static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
 	if (tree == o->df_conflict_entry)
 		tree = NULL;
 
-	if (ce_path_match(idx ? idx : tree, &revs->prune_data))
+	if (ce_path_match(idx ? idx : tree, &revs->prune_data)) {
 		do_oneway_diff(o, idx, tree);
+		if (diff_can_quit_early(&revs->diffopt)) {
+			o->exiting_early = 1;
+			return -1;
+		}
+	}
 
 	return 0;
 }

unpack-trees.c

@@ -593,7 +593,7 @@ static int unpack_nondirectories(int n, unsigned long mask,
 static int unpack_failed(struct unpack_trees_options *o, const char *message)
 {
 	discard_index(&o->result);
-	if (!o->gently) {
+	if (!o->gently && !o->exiting_early) {
 		if (message)
 			return error("%s", message);
 		return -1;
@@ -1133,6 +1133,8 @@ return_failed:
 		display_error_msgs(o);
 	mark_all_ce_unused(o->src_index);
 	ret = unpack_failed(o, NULL);
+	if (o->exiting_early)
+		ret = 0;
 	goto done;
 }
 

unpack-trees.h

@@ -46,6 +46,7 @@ struct unpack_trees_options {
 		     debug_unpack,
 		     skip_sparse_checkout,
 		     gently,
+		     exiting_early,
 		     show_all_errors,
 		     dry_run;
 	const char *prefix;