Revert #96682.

The change was "Show invisible delimiters (within comments) when pretty
printing". It's useful to show these delimiters, but is a breaking
change for some proc macros.

Fixes #97608.

2 files changed, 7 insertions, 21 deletions

diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs
index 1522d12cbf9..85d9687c600 100644
--- a/compiler/rustc_ast/src/token.rs
+++ b/compiler/rustc_ast/src/token.rs
@@ -50,12 +50,11 @@ pub enum Delimiter {
     Brace,
     /// `[ ... ]`
     Bracket,
-    /// `/*«*/ ... /*»*/`
+    /// `Ø ... Ø`
     /// An invisible delimiter, that may, for example, appear around tokens coming from a
     /// "macro variable" `$var`. It is important to preserve operator priorities in cases like
     /// `$var * 3` where `$var` is `1 + 2`.
-    /// Invisible delimiters are not directly writable in normal Rust code except as comments.
-    /// Therefore, they might not survive a roundtrip of a token stream through a string.
+    /// Invisible delimiters might not survive roundtrip of a token stream through a string.
     Invisible,
 }
 
diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs
index 7357ddf2134..b80a553b418 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state.rs
@@ -590,28 +590,14 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
                     self.nbsp();
                 }
                 self.word("{");
-                let empty = tts.is_empty();
-                if !empty {
+                if !tts.is_empty() {
                     self.space();
                 }
                 self.ibox(0);
                 self.print_tts(tts, convert_dollar_crate);
                 self.end();
-                self.bclose(span, empty);
-            }
-            Some(Delimiter::Invisible) => {
-                self.word("/*«*/");
                 let empty = tts.is_empty();
-                if !empty {
-                    self.space();
-                }
-                self.ibox(0);
-                self.print_tts(tts, convert_dollar_crate);
-                self.end();
-                if !empty {
-                    self.space();
-                }
-                self.word("/*»*/");
+                self.bclose(span, empty);
             }
             Some(delim) => {
                 let token_str = self.token_kind_to_string(&token::OpenDelim(delim));
@@ -786,8 +772,9 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
             token::CloseDelim(Delimiter::Bracket) => "]".into(),
             token::OpenDelim(Delimiter::Brace) => "{".into(),
             token::CloseDelim(Delimiter::Brace) => "}".into(),
-            token::OpenDelim(Delimiter::Invisible) => "/*«*/".into(),
-            token::CloseDelim(Delimiter::Invisible) => "/*»*/".into(),
+            token::OpenDelim(Delimiter::Invisible) | token::CloseDelim(Delimiter::Invisible) => {
+                "".into()
+            }
             token::Pound => "#".into(),
             token::Dollar => "$".into(),
             token::Question => "?".into(),