Remove `token::{Open,Close}Delim`.

By replacing them with `{Open,Close}{Param,Brace,Bracket,Invisible}`.

PR #137902 made `ast::TokenKind` more like `lexer::TokenKind` by
replacing the compound `BinOp{,Eq}(BinOpToken)` variants with fieldless
variants `Plus`, `Minus`, `Star`, etc. This commit does a similar thing
with delimiters. It also makes `ast::TokenKind` more similar to
`parser::TokenType`.

This requires a few new methods:
- `TokenKind::is_{,open_,close_}delim()` replace various kinds of
  pattern matches.
- `Delimiter::as_{open,close}_token_kind` are used to convert
  `Delimiter` values to `TokenKind`.

Despite these additions, it's a net reduction in lines of code. This is
because e.g. `token::OpenParen` is so much shorter than
`token::OpenDelim(Delimiter::Parenthesis)` that many multi-line forms
reduce to single line forms. And many places where the number of lines
doesn't change are still easier to read, just because the names are
shorter, e.g.:
```
-   } else if self.token != token::CloseDelim(Delimiter::Brace) {
+   } else if self.token != token::CloseBrace {
```

1 files changed, 9 insertions, 10 deletions

diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs
index 0985ebf945b..6959cbd87f1 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state.rs
@@ -770,12 +770,12 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
                 self.bclose(span, empty);
             }
             delim => {
-                let token_str = self.token_kind_to_string(&token::OpenDelim(delim));
+                let token_str = self.token_kind_to_string(&delim.as_open_token_kind());
                 self.word(token_str);
                 self.ibox(0);
                 self.print_tts(tts, convert_dollar_crate);
                 self.end();
-                let token_str = self.token_kind_to_string(&token::CloseDelim(delim));
+                let token_str = self.token_kind_to_string(&delim.as_close_token_kind());
                 self.word(token_str);
             }
         }
@@ -932,14 +932,13 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
             token::RArrow => "->".into(),
             token::LArrow => "<-".into(),
             token::FatArrow => "=>".into(),
-            token::OpenDelim(Delimiter::Parenthesis) => "(".into(),
-            token::CloseDelim(Delimiter::Parenthesis) => ")".into(),
-            token::OpenDelim(Delimiter::Bracket) => "[".into(),
-            token::CloseDelim(Delimiter::Bracket) => "]".into(),
-            token::OpenDelim(Delimiter::Brace) => "{".into(),
-            token::CloseDelim(Delimiter::Brace) => "}".into(),
-            token::OpenDelim(Delimiter::Invisible(_))
-            | token::CloseDelim(Delimiter::Invisible(_)) => "".into(),
+            token::OpenParen => "(".into(),
+            token::CloseParen => ")".into(),
+            token::OpenBracket => "[".into(),
+            token::CloseBracket => "]".into(),
+            token::OpenBrace => "{".into(),
+            token::CloseBrace => "}".into(),
+            token::OpenInvisible(_) | token::CloseInvisible(_) => "".into(),
             token::Pound => "#".into(),
             token::Dollar => "$".into(),
             token::Question => "?".into(),