add tests

src/test/compile-fail/for-loop-hygiene.rs

@@ -0,0 +1,20 @@
+// Copyright 2014 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.
+
+// for-loops are expanded in the front end, and use an `iter` ident in their expansion. Check that
+// `iter` is not accessible inside the for loop.
+
+#![allow(unstable)]
+
+fn main() {
+    for _ in 0..10 {
+        iter.next();  //~ error: unresolved name `iter`
+    }
+}

src/test/run-pass/for-loop-into-iterator.rs

@@ -0,0 +1,27 @@
+// Copyright 2014 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.
+
+// Test that for loops can do what RFC #235 claims
+
+fn main() {
+    let mut v = vec![1];
+
+    for x in &v {
+        assert_eq!(x, &1);
+    }
+
+    for x in &mut v {
+        assert_eq!(x, &mut 1);
+    }
+
+    for x in v {
+        assert_eq!(x, 1);
+    }
+}