Add test for #6861

Author: luqmana

src/test/run-pass/unit-like-struct-drop-run.rs

@@ -0,0 +1,28 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Make sure the destructor is run for unit-like structs.
+
+use std::task;
+
+struct Foo;
+
+impl Drop for Foo {
+    fn finalize(&self) {
+        fail!("This failure should happen.");
+    }
+}
+
+fn main() {
+    let x = do task::try {
+        let _b = Foo;
+    };
+    assert_eq!(x, Err(()));
+}