Move /src/test to /tests

tests/ui/empty/empty-struct-unit-expr.rs

@@ -0,0 +1,21 @@
+// Can't use unit struct as constructor function
+
+// aux-build:empty-struct.rs
+
+extern crate empty_struct;
+use empty_struct::*;
+
+struct Empty2;
+
+enum E {
+    Empty4
+}
+
+fn main() {
+    let e2 = Empty2(); //~ ERROR expected function, found struct `Empty2`
+    let e4 = E::Empty4();
+    //~^ ERROR expected function, found enum variant `E::Empty4` [E0618]
+    let xe2 = XEmpty2(); //~ ERROR expected function, found struct `XEmpty2`
+    let xe4 = XE::XEmpty4();
+    //~^ ERROR expected function, found enum variant `XE::XEmpty4` [E0618]
+}