branch: move 'current' check down to the presentation layer

We check if given ref is the current branch in print_ref_list(). Move
this check to print_ref_item() where it is checked right before
printing. This enables a smooth transition to using ref-filter APIs,
as we can later replace the current check while printing to just check
for FILTER_REFS_DETACHED instead.

Based-on-patch-by: Jeff King <peff@peff.net>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/branch.c

@@ -534,9 +534,10 @@ static char *get_head_description(void)
 }
 
 static void print_ref_item(struct ref_item *item, int maxwidth, int verbose,
-			   int abbrev, int current, const char *remote_prefix)
+			   int abbrev, int detached, const char *remote_prefix)
 {
 	char c;
+	int current = 0;
 	int color;
 	struct strbuf out = STRBUF_INIT, name = STRBUF_INIT;
 	const char *prefix = "";
@@ -548,15 +549,18 @@ static void print_ref_item(struct ref_item *item, int maxwidth, int verbose,
 
 	switch (item->kind) {
 	case REF_LOCAL_BRANCH:
-		color = BRANCH_COLOR_LOCAL;
+		if (!detached && !strcmp(item->name, head))
+			current = 1;
+		else
+			color = BRANCH_COLOR_LOCAL;
 		break;
 	case REF_REMOTE_BRANCH:
 		color = BRANCH_COLOR_REMOTE;
 		prefix = remote_prefix;
 		break;
 	case REF_DETACHED_HEAD:
-		color = BRANCH_COLOR_CURRENT;
 		desc = to_free = get_head_description();
+		current = 1;
 		break;
 	default:
 		color = BRANCH_COLOR_PLAIN;
@@ -684,15 +688,9 @@ static int print_ref_list(int kinds, int detached, int verbose, int abbrev, stru
 
 	qsort(ref_list.list, ref_list.index, sizeof(struct ref_item), ref_cmp);
 
-	for (i = 0; i < ref_list.index; i++) {
-		int current = !detached && (ref_list.list[i].kind == REF_LOCAL_BRANCH) &&
-			!strcmp(ref_list.list[i].name, head);
-		/*  If detached the first ref_item is the current ref */
-		if (detached && i == 0)
-			current = 1;
+	for (i = 0; i < ref_list.index; i++)
 		print_ref_item(&ref_list.list[i], maxwidth, verbose,
-			       abbrev, current, remote_prefix);
-	}
+			       abbrev, detached, remote_prefix);
 
 	free_ref_list(&ref_list);