Add regression test.

Author: jseyfried

src/test/compile-fail/paths-in-macro-invocations.rs

@@ -0,0 +1,38 @@
+// Copyright 2016 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.
+
+::foo::bar!(); //~ ERROR expected macro name without module separators
+foo::bar!(); //~ ERROR expected macro name without module separators
+
+trait T {
+    foo::bar!(); //~ ERROR expected macro name without module separators
+    ::foo::bar!(); //~ ERROR expected macro name without module separators
+}
+
+struct S {
+    x: foo::bar!(), //~ ERROR expected macro name without module separators
+    y: ::foo::bar!(), //~ ERROR expected macro name without module separators
+}
+
+impl S {
+    foo::bar!(); //~ ERROR expected macro name without module separators
+    ::foo::bar!(); //~ ERROR expected macro name without module separators
+}
+
+fn main() {
+    foo::bar!(); //~ ERROR expected macro name without module separators
+    ::foo::bar!(); //~ ERROR expected macro name without module separators
+
+    let _ = foo::bar!(); //~ ERROR expected macro name without module separators
+    let _ = ::foo::bar!(); //~ ERROR expected macro name without module separators
+
+    let foo::bar!() = 0; //~ ERROR expected macro name without module separators
+    let ::foo::bar!() = 0; //~ ERROR expected macro name without module separators
+}