Auto merge of #29714 - petrochenkov:strparse, r=nrc

In particular, attributes are now parsed on fields of tuple variants

src/test/compile-fail/issue-12560-1.rs

@@ -8,15 +8,15 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -Z parse-only
-
 // For style and consistency reasons, non-parametrized enum variants must
 // be used simply as `ident` instead of `ident ()`.
 // This test-case covers enum declaration.
 
 enum Foo {
-    Bar(), //~ ERROR nullary enum variants are written with no trailing `( )`
-    Baz(), //~ ERROR nullary enum variants are written with no trailing `( )`
+    Bar(), //~ ERROR empty tuple structs and enum variants are not allowed
+    //~^ HELP remove trailing `()` to make a unit struct or unit enum variant
+    Baz(), //~ ERROR empty tuple structs and enum variants are not allowed
+    //~^ HELP remove trailing `()` to make a unit struct or unit enum variant
     Bazar
 }
 

src/test/compile-fail/issue-16819.rs

@@ -10,9 +10,17 @@
 
 struct TS ( //~ ERROR empty tuple structs and enum variants are not allowed
     #[cfg(untrue)]
-    int,
+    i32,
 );
 
-fn main() {
-    let s = S;
+enum E {
+    TV ( //~ ERROR empty tuple structs and enum variants are not allowed
+        #[cfg(untrue)]
+        i32,
+    )
+}
+
+fn main() {
+    let s = TS;
+    let tv = E::TV;
 }