Implement empty struct with braces (RFC 218)

src/test/compile-fail/empty-struct-with-braces-1.rs

@@ -1,4 +1,4 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// 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.
 //
@@ -8,13 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -Z parse-only
+// Empty struct defined with braces shouldn't add names into value namespace
 
-struct Foo;
+struct Empty {}
 
-fn f2() {
-    let _end_stmt     = Foo { };
-    //~^ ERROR: structure literal must either have at least one field
+fn main() {
+    let e = Empty; //~ ERROR `Empty` is the name of a struct or struct variant
 }
-
-fn main() {}

src/test/compile-fail/empty-struct-with-braces-2.rs

@@ -1,4 +1,4 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// 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.
 //
@@ -8,13 +8,17 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -Z parse-only
+// Empty struct defined with braces shouldn't add names into value namespace
 
-struct Foo;
+#![deny(warnings)]
 
-fn g3() {
-    let _mid_tuple    = (Foo { }, 2);
-    //~^ ERROR: structure literal must either have at least one field
+struct Empty {}
+
+fn main() {
+    let e = Empty {};
+
+    match e {
+        Empty => () //~ ERROR unused variable: `Empty`
+        //~^ ERROR variable `Empty` should have a snake case name such as `empty`
+    }
 }
-
-fn main() {}

src/test/compile-fail/issue-27831.rs

@@ -22,8 +22,8 @@ fn main() {
     let Foo { .. } = x; //~ ERROR `Foo` does not name a struct
 
     let x = Bar;
-    Bar { ..x }; //~ ERROR `Bar` does not name a structure
-    let Bar { .. } = x; //~ ERROR `Bar` does not name a struct
+    Bar { ..x };
+    let Bar { .. } = x;
 
     match Enum::Bar {
         Enum::Bar { .. } //~ ERROR `Enum::Bar` does not name a struct

src/test/parse-fail/struct-no-fields-4.rs

@@ -1,20 +0,0 @@
-// Copyright 2013 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.
-
-// compile-flags: -Z parse-only
-
-struct Foo;
-
-fn h4() {
-    let _end_of_tuple = (3, Foo { });
-    //~^ ERROR: structure literal must either have at least one field
-}
-
-fn main() {}

src/test/parse-fail/struct-no-fields-5.rs

@@ -1,20 +0,0 @@
-// Copyright 2013 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.
-
-// compile-flags: -Z parse-only
-
-struct Foo;
-
-fn i5() {
-    let _end_of_block = { Foo { } };
-    //~^ ERROR: structure literal must either have at least one field
-}
-
-fn main() {}

src/test/run-pass/empty-struct-with-braces.rs

@@ -0,0 +1,31 @@
+// 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.
+
+// Empty struct defined with braces add names into type namespace
+// Empty struct defined without braces add names into both type and value namespaces
+
+struct Empty1 {}
+struct Empty2;
+
+fn main() {
+    let e1: Empty1 = Empty1 {};
+    let e2: Empty2 = Empty2 {};
+    let e2: Empty2 = Empty2;
+
+    match e1 {
+        Empty1 {} => ()
+    }
+    match e2 {
+        Empty2 {} => ()
+    }
+    match e2 {
+        Empty2 => ()
+    }
+}

src/test/run-pass/issue-16819.rs

@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// 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.
 //
@@ -8,9 +8,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -Z parse-only
+//`#[cfg]` on struct field permits empty unusable struct
 
-struct Foo {}
-//~^ ERROR: unit-like struct definition should be written as `struct Foo;`
+struct S {
+    #[cfg(untrue)]
+    a: int,
+}
 
-fn main() {}
+fn main() {
+    let s = S {};
+}