read-cache.c: split racy stat test to a separate function

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

read-cache.c

@@ -272,20 +272,26 @@ static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
 	return changed;
 }
 
+static int is_racy_stat(const struct index_state *istate,
+			const struct stat_data *sd)
+{
+	return (istate->timestamp.sec &&
+#ifdef USE_NSEC
+		 /* nanosecond timestamped files can also be racy! */
+		(istate->timestamp.sec < sd->sd_mtime.sec ||
+		 (istate->timestamp.sec == sd->sd_mtime.sec &&
+		  istate->timestamp.nsec <= sd->sd_mtime.nsec))
+#else
+		istate->timestamp.sec <= sd->sd_mtime.sec
+#endif
+		);
+}
+
 static int is_racy_timestamp(const struct index_state *istate,
 			     const struct cache_entry *ce)
 {
 	return (!S_ISGITLINK(ce->ce_mode) &&
-		istate->timestamp.sec &&
-#ifdef USE_NSEC
-		 /* nanosecond timestamped files can also be racy! */
-		(istate->timestamp.sec < ce->ce_stat_data.sd_mtime.sec ||
-		 (istate->timestamp.sec == ce->ce_stat_data.sd_mtime.sec &&
-		  istate->timestamp.nsec <= ce->ce_stat_data.sd_mtime.nsec))
-#else
-		istate->timestamp.sec <= ce->ce_stat_data.sd_mtime.sec
-#endif
-		 );
+		is_racy_stat(istate, &ce->ce_stat_data));
 }
 
 int ie_match_stat(const struct index_state *istate,