Implement RFC 2128 (use_nested_groups)

This commit adds support for nested groups inside `use` declarations,
such as `use foo::{bar, sub::{baz::Foo, *}};`.

1 files changed, 22 insertions, 0 deletions

diff --git a/src/test/compile-fail/absolute-paths-in-nested-use-groups.rs b/src/test/compile-fail/absolute-paths-in-nested-use-groups.rs
new file mode 100644
index 00000000000..8e5ba489c56
--- /dev/null
+++ b/src/test/compile-fail/absolute-paths-in-nested-use-groups.rs
@@ -0,0 +1,22 @@
+// Copyright 2017 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(use_nested_groups)]
+#![allow(unused_imports)]
+
+mod foo {}
+
+use foo::{
+    ::bar,       //~ ERROR crate root in paths can only be used in start position
+    super::bar,  //~ ERROR `super` in paths can only be used in start position
+    self::bar,   //~ ERROR `self` in paths can only be used in start position
+};
+
+fn main() {}