From 6ac83de691c5eb180e2007fcbe3236fd359d2ab7 Mon Sep 17 00:00:00 2001
From: Knight <knight42@mail.ustc.edu.cn>
Date: Wed, 27 Jul 2016 02:30:50 +0800
Subject: [PATCH] Add test for string AddAssign

---
 src/libcollectionstest/string.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/libcollectionstest/string.rs b/src/libcollectionstest/string.rs
index 7f0fd282ae5e9..1652fb5a88d80 100644
--- a/src/libcollectionstest/string.rs
+++ b/src/libcollectionstest/string.rs
@@ -192,6 +192,17 @@ fn test_push_str() {
     assert_eq!(&s[0..], "abcประเทศไทย中华Việt Nam");
 }
 
+#[test]
+fn test_add_assign() {
+    let mut s = String::new();
+    s += "";
+    assert_eq!(s.as_str(), "");
+    s += "abc";
+    assert_eq!(s.as_str(), "abc");
+    s += "ประเทศไทย中华Việt Nam";
+    assert_eq!(s.as_str(), "abcประเทศไทย中华Việt Nam");
+}
+
 #[test]
 fn test_push() {
     let mut data = String::from("ประเทศไทย中");