Rollup merge of #62258 - petrochenkov:idclean, r=Centril

syntax: Unsupport `foo! bar { ... }` macros in the parser

Their support in expansion was removed in https://github.com/rust-lang/rust/pull/61606.

Also un-reserve `macro_rules` as a macro name, there's no ambiguity between `macro_rules` definitions and macro calls (it also wasn't reserved correctly).

cc https://github.com/rust-lang-nursery/wg-grammar/issues/51

src/test/ui/issues/issue-10536.rs

@@ -11,13 +11,9 @@ macro_rules! foo{
 pub fn main() {
     foo!();
 
-    assert!({one! two()});
-    //~^ ERROR macros that expand to items
-    //~| ERROR cannot find macro `one!` in this scope
-    //~| ERROR mismatched types
+    assert!({one! two()}); //~ ERROR expected open delimiter
 
     // regardless of whether nested macro_rules works, the following should at
     // least throw a conventional error.
-    assert!({one! two});
-    //~^ ERROR expected `(` or `{`, found `}`
+    assert!({one! two}); //~ ERROR expected open delimiter
 }

src/test/ui/issues/issue-10536.stderr

@@ -1,38 +1,14 @@
-error: macros that expand to items must be delimited with braces or followed by a semicolon
-  --> $DIR/issue-10536.rs:14:22
+error: expected open delimiter
+  --> $DIR/issue-10536.rs:14:19
    |
 LL |     assert!({one! two()});
-   |                      ^^
-help: change the delimiters to curly braces
-   |
-LL |     assert!({one! two {}});
-   |                       ^^
-help: add a semicolon
-   |
-LL |     assert!({one! two();});
-   |                        ^
+   |                   ^^^ expected open delimiter
 
-error: expected `(` or `{`, found `}`
-  --> $DIR/issue-10536.rs:21:22
+error: expected open delimiter
+  --> $DIR/issue-10536.rs:18:19
    |
 LL |     assert!({one! two});
-   |                      ^ expected `(` or `{`
+   |                   ^^^ expected open delimiter
 
-error: cannot find macro `one!` in this scope
-  --> $DIR/issue-10536.rs:14:14
-   |
-LL |     assert!({one! two()});
-   |              ^^^
+error: aborting due to 2 previous errors
 
-error[E0308]: mismatched types
-  --> $DIR/issue-10536.rs:14:13
-   |
-LL |     assert!({one! two()});
-   |             ^^^^^^^^^^^^ expected bool, found ()
-   |
-   = note: expected type `bool`
-              found type `()`
-
-error: aborting due to 4 previous errors
-
-For more information about this error, try `rustc --explain E0308`.

src/test/ui/parser/macro-bad-delimiter-ident.rs

@@ -1,3 +1,3 @@
 fn main() {
-    foo! bar < //~ ERROR expected `(` or `{`, found `<`
+    foo! bar < //~ ERROR expected open delimiter
 }

src/test/ui/parser/macro-bad-delimiter-ident.stderr

@@ -1,8 +1,8 @@
-error: expected `(` or `{`, found `<`
-  --> $DIR/macro-bad-delimiter-ident.rs:2:14
+error: expected open delimiter
+  --> $DIR/macro-bad-delimiter-ident.rs:2:10
    |
 LL |     foo! bar <
-   |              ^ expected `(` or `{`
+   |          ^^^ expected open delimiter
 
 error: aborting due to previous error
 

src/test/ui/user-defined-macro-rules.rs

@@ -1,5 +1,9 @@
-#![allow(unused_macros)]
+// check-pass
 
-macro_rules! macro_rules { () => {} } //~ ERROR user-defined macros may not be named `macro_rules`
+macro_rules! macro_rules { () => { struct S; } } // OK
 
-fn main() {}
+macro_rules! {} // OK, calls the macro defined above
+
+fn main() {
+    let s = S;
+}

src/test/ui/user-defined-macro-rules.stderr

@@ -1,8 +0,0 @@
-error: user-defined macros may not be named `macro_rules`
-  --> $DIR/user-defined-macro-rules.rs:3:1
-   |
-LL | macro_rules! macro_rules { () => {} }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-