---

yaml
---
r: 152323
b: refs/heads/try2
c: 3fecd10
h: refs/heads/master
i:
  152321: 4d3e301
  152319: 3ded02a
v: v3

Author: nikomatsakis

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
 refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: bc5eb7d98c9ef2ede97f1cb533936ab8210d49a4
+refs/heads/try2: 3fecd10428bbefd162a75512acb807dd65dcb1dd
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/src/test/run-pass/trait-contravariant-self.rs

@@ -0,0 +1,37 @@
+// 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.
+
+// This is an interesting test case. We have a trait (Bar) that is
+// implemented for a `Box<Foo>` object (note: no bounds). And then we
+// have a `Box<Foo:Send>` object. The impl for `Box<Foo>` is applicable
+// to `Box<Foo:Send>` because:
+//
+// 1. The trait Bar is contravariant w/r/t Self because `Self` appears
+//    only in argument position.
+// 2. The impl provides `Bar for Box<Foo>`
+// 3. The fn `wants_bar()` requires `Bar for Box<Foo:Send>`.
+// 4. `Bar for Box<Foo> <: Bar for Box<Foo:Send>` because
+//    `Box<Foo:Send> <: Box<Foo>`.
+
+trait Foo { }
+struct SFoo;
+impl Foo for SFoo { }
+
+trait Bar { fn dummy(&self); }
+impl Bar for Box<Foo> { fn dummy(&self) { } }
+
+fn wants_bar<B:Bar>(b: &B) { }
+
+fn main() {
+    let x: Box<Foo:Send> = (box SFoo);
+    wants_bar(&x);
+}
+
+