Add a rustfix test to the test project

Author: phansch

test-project/tests/tests.rs

@@ -19,6 +19,7 @@ fn run_mode(mode: &'static str) {
 fn compile_test() {
     run_mode("compile-fail");
     run_mode("run-pass");
+    run_mode("ui");
 
     #[cfg(not(feature = "stable"))]
     run_mode("pretty");

test-project/tests/ui/dyn-keyword.fixed

@@ -0,0 +1,19 @@
+// Copyright 2018 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.
+
+// run-rustfix
+
+#![allow(unused_variables)]
+#![deny(keyword_idents)]
+
+fn main() {
+    let r#dyn = (); //~ ERROR dyn
+    //~^ WARN hard error in the 2018 edition
+}

test-project/tests/ui/dyn-keyword.rs

@@ -0,0 +1,19 @@
+// Copyright 2018 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.
+
+// run-rustfix
+
+#![allow(unused_variables)]
+#![deny(keyword_idents)]
+
+fn main() {
+    let dyn = (); //~ ERROR dyn
+    //~^ WARN hard error in the 2018 edition
+}

test-project/tests/ui/dyn-keyword.stderr

@@ -0,0 +1,16 @@
+error: `dyn` is a keyword in the 2018 edition
+  --> $DIR/dyn-keyword.rs:17:9
+   |
+17 |     let dyn = (); //~ ERROR dyn
+   |         ^^^ help: you can use a raw identifier to stay compatible: `r#dyn`
+   |
+note: lint level defined here
+  --> $DIR/dyn-keyword.rs:14:9
+   |
+14 | #![deny(keyword_idents)]
+   |         ^^^^^^^^^^^^^^
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
+   = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
+
+error: aborting due to previous error
+