diff --git a/library/alloc/tests/str.rs b/library/alloc/tests/str.rs
index b20cf076aca..411893d65de 100644
--- a/library/alloc/tests/str.rs
+++ b/library/alloc/tests/str.rs
@@ -1921,3 +1921,11 @@ fn different_str_pattern_forwarding_lifetimes() {
 
     foo::<&str>("x");
 }
+
+#[test]
+fn test_str_concat() {
+    let a: String = "hello".to_string();
+    let b: String = "world".to_string();
+    let s: String = format!("{}{}", a, b);
+    assert_eq!(s.as_bytes()[9], 'd' as u8);
+}
diff --git a/src/test/ui/str-concat.rs b/src/test/ui/str-concat.rs
deleted file mode 100644
index fa2fc97d7b8..00000000000
--- a/src/test/ui/str-concat.rs
+++ /dev/null
@@ -1,9 +0,0 @@
-// run-pass
-
-pub fn main() {
-    let a: String = "hello".to_string();
-    let b: String = "world".to_string();
-    let s: String = format!("{}{}", a, b);
-    println!("{}", s.clone());
-    assert_eq!(s.as_bytes()[9], 'd' as u8);
-}