From 8be07194c7717253aaf16daa9c614ce1f0994b2f Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Thu, 20 Feb 2020 18:33:38 +0800
Subject: [PATCH] string: fix capitalize

---
 vlib/builtin/string.v      | 3 +++
 vlib/builtin/string_test.v | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/vlib/builtin/string.v b/vlib/builtin/string.v
index b024f13b3f..dea073067e 100644
--- a/vlib/builtin/string.v
+++ b/vlib/builtin/string.v
@@ -752,6 +752,9 @@ pub fn (s string) to_upper() string {
 }
 
 pub fn (s string) capitalize() string {
+	if s.len == 0 {
+		return ''
+	}
 	sl := s.to_lower()
 	cap := sl[0].str().to_upper() + sl.right(1)
 	return cap
diff --git a/vlib/builtin/string_test.v b/vlib/builtin/string_test.v
index fae933c60c..b558f123cc 100644
--- a/vlib/builtin/string_test.v
+++ b/vlib/builtin/string_test.v
@@ -503,6 +503,8 @@ fn test_capitalize() {
 	assert s.capitalize() == 'Test'
     s = 'i am ray'
 	assert s.capitalize() == 'I am ray'
+	s = ''
+	assert s.capitalize() == ''
 }
 
 fn test_title() {