Auto merge of rust-lang#138083 - nnethercote:rm-NtItem-NtStmt, r=<try>

Remove `NtItem` and `NtStmt`

Another piece of rust-lang#124141.

r? `@petrochenkov`

Author: bors

compiler/rustc_expand/src/proc_macro.rs

@@ -122,7 +122,7 @@ impl MultiItemModifier for DeriveProcMacro {
         // We had a lint for a long time, but now we just emit a hard error.
         // Eventually we might remove the special case hard error check
         // altogether. See #73345.
-        crate::base::ann_pretty_printing_compatibility_hack(&item, &ecx.sess);
+        crate::base::ann_pretty_printing_compatibility_hack(&item, &ecx.sess.psess);
         let input = item.to_tokens();
         let stream = {
             let _timer =

compiler/rustc_expand/src/proc_macro_server.rs

@@ -115,11 +115,43 @@ impl FromInternal<(TokenStream, &mut Rustc<'_, '_>)> for Vec<TokenTree<TokenStre
 
         while let Some(tree) = iter.next() {
             let (Token { kind, span }, joint) = match tree.clone() {
-                tokenstream::TokenTree::Delimited(span, _, delim, tts) => {
-                    let delimiter = pm::Delimiter::from_internal(delim);
+                tokenstream::TokenTree::Delimited(span, _, mut delim, mut stream) => {
+                    // We used to have an alternative behaviour for crates that
+                    // needed it: a hack used to pass AST fragments to
+                    // attribute and derive macros as a single nonterminal
+                    // token instead of a token stream. Such token needs to be
+                    // "unwrapped" and not represented as a delimited group. We
+                    // had a lint for a long time, but now we just emit a hard
+                    // error. Eventually we might remove the special case hard
+                    // error check altogether. See #73345.
+                    if let Delimiter::Invisible(InvisibleOrigin::MetaVar(kind)) = delim {
+                        crate::base::stream_pretty_printing_compatibility_hack(
+                            kind,
+                            &stream,
+                            rustc.psess(),
+                        );
+                    }
+
+                    // In `mk_delimited` we avoid nesting invisible delimited
+                    // of the same `MetaVarKind`. Here we do the same but
+                    // ignore the `MetaVarKind` because it is discarded when we
+                    // convert it to a `Group`.
+                    while let Delimiter::Invisible(InvisibleOrigin::MetaVar(_)) = delim {
+                        if stream.len() == 1
+                            && let tree = stream.iter().next().unwrap()
+                            && let tokenstream::TokenTree::Delimited(_, _, delim2, stream2) = tree
+                            && let Delimiter::Invisible(InvisibleOrigin::MetaVar(_)) = delim2
+                        {
+                            delim = *delim2;
+                            stream = stream2.clone();
+                        } else {
+                            break;
+                        }
+                    }
+
                     trees.push(TokenTree::Group(Group {
-                        delimiter,
-                        stream: Some(tts),
+                        delimiter: pm::Delimiter::from_internal(delim),
+                        stream: Some(stream),
                         span: DelimSpan {
                             open: span.open,
                             close: span.close,
@@ -279,15 +311,6 @@ impl FromInternal<(TokenStream, &mut Rustc<'_, '_>)> for Vec<TokenTree<TokenStre
 
                 Interpolated(nt) => {
                     let stream = TokenStream::from_nonterminal_ast(&nt);
-                    // We used to have an alternative behaviour for crates that
-                    // needed it: a hack used to pass AST fragments to
-                    // attribute and derive macros as a single nonterminal
-                    // token instead of a token stream. Such token needs to be
-                    // "unwrapped" and not represented as a delimited group. We
-                    // had a lint for a long time, but now we just emit a hard
-                    // error. Eventually we might remove the special case hard
-                    // error check altogether. See #73345.
-                    crate::base::nt_pretty_printing_compatibility_hack(&nt, rustc.ecx.sess);
                     trees.push(TokenTree::Group(Group {
                         delimiter: pm::Delimiter::None,
                         stream: Some(stream),

compiler/rustc_hir/src/lib.rs

@@ -4,6 +4,7 @@
 
 // tidy-alphabetical-start
 #![allow(internal_features)]
+#![cfg_attr(doc, recursion_limit = "256")] // FIXME(nnethercote): will be removed by #124141
 #![feature(associated_type_defaults)]
 #![feature(box_patterns)]
 #![feature(closure_track_caller)]