Move /src/test to /tests

tests/ui/lint/dead-code/basic.rs

@@ -0,0 +1,15 @@
+#![deny(dead_code)]
+#![allow(unreachable_code)]
+
+fn foo() { //~ ERROR function `foo` is never used
+
+    // none of these should have any dead_code exposed to the user
+    panic!();
+
+    panic!("foo");
+
+    panic!("bar {}", "baz")
+}
+
+
+fn main() {}