ls-files: factor out tag calculation

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/ls-files.c

@@ -93,6 +93,30 @@ static void write_name(const char *name)
 	strbuf_release(&full_name);
 }
 
+static const char *get_tag(const struct cache_entry *ce, const char *tag)
+{
+	static char alttag[4];
+
+	if (tag && *tag && show_valid_bit && (ce->ce_flags & CE_VALID)) {
+		memcpy(alttag, tag, 3);
+
+		if (isalpha(tag[0])) {
+			alttag[0] = tolower(tag[0]);
+		} else if (tag[0] == '?') {
+			alttag[0] = '!';
+		} else {
+			alttag[0] = 'v';
+			alttag[1] = tag[0];
+			alttag[2] = ' ';
+			alttag[3] = 0;
+		}
+
+		tag = alttag;
+	}
+
+	return tag;
+}
+
 static void print_debug(const struct cache_entry *ce)
 {
 	if (debug_mode) {
@@ -264,22 +288,7 @@ static void show_ce_entry(const struct index_state *istate,
 				  len, ps_matched,
 				  S_ISDIR(ce->ce_mode) ||
 				  S_ISGITLINK(ce->ce_mode))) {
-		if (tag && *tag && show_valid_bit &&
-		    (ce->ce_flags & CE_VALID)) {
-			static char alttag[4];
-			memcpy(alttag, tag, 3);
-			if (isalpha(tag[0]))
-				alttag[0] = tolower(tag[0]);
-			else if (tag[0] == '?')
-				alttag[0] = '!';
-			else {
-				alttag[0] = 'v';
-				alttag[1] = tag[0];
-				alttag[2] = ' ';
-				alttag[3] = 0;
-			}
-			tag = alttag;
-		}
+		tag = get_tag(ce, tag);
 
 		if (!show_stage) {
 			fputs(tag, stdout);