Add test of impl formatting

Author: wthrowe

src/test/rustdoc/impl-parts.rs

@@ -0,0 +1,23 @@
+// Copyright 2015 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.
+
+#![feature(optin_builtin_traits)]
+
+pub trait AnOibit {}
+
+impl AnOibit for .. {}
+
+pub struct Foo<T> { field: T }
+
+// @has impl_parts/struct.Foo.html '//*[@class="impl"]//code' \
+//     "impl<T: Clone> !AnOibit for Foo<T> where T: Sync"
+// @has impl_parts/trait.AnOibit.html '//*[@class="item-list"]//code' \
+//     "impl<T: Clone> !AnOibit for Foo<T> where T: Sync"
+impl<T: Clone> !AnOibit for Foo<T> where T: Sync {}