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, 6 insertions, 6 deletions

diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index 4935fc03256..a8ec9a1e952 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -371,12 +371,12 @@ impl<'psess, 'src> Lexer<'psess, 'src> {
                 rustc_lexer::TokenKind::Semi => token::Semi,
                 rustc_lexer::TokenKind::Comma => token::Comma,
                 rustc_lexer::TokenKind::Dot => token::Dot,
-                rustc_lexer::TokenKind::OpenParen => token::OpenDelim(Delimiter::Parenthesis),
-                rustc_lexer::TokenKind::CloseParen => token::CloseDelim(Delimiter::Parenthesis),
-                rustc_lexer::TokenKind::OpenBrace => token::OpenDelim(Delimiter::Brace),
-                rustc_lexer::TokenKind::CloseBrace => token::CloseDelim(Delimiter::Brace),
-                rustc_lexer::TokenKind::OpenBracket => token::OpenDelim(Delimiter::Bracket),
-                rustc_lexer::TokenKind::CloseBracket => token::CloseDelim(Delimiter::Bracket),
+                rustc_lexer::TokenKind::OpenParen => token::OpenParen,
+                rustc_lexer::TokenKind::CloseParen => token::CloseParen,
+                rustc_lexer::TokenKind::OpenBrace => token::OpenBrace,
+                rustc_lexer::TokenKind::CloseBrace => token::CloseBrace,
+                rustc_lexer::TokenKind::OpenBracket => token::OpenBracket,
+                rustc_lexer::TokenKind::CloseBracket => token::CloseBracket,
                 rustc_lexer::TokenKind::At => token::At,
                 rustc_lexer::TokenKind::Pound => token::Pound,
                 rustc_lexer::TokenKind::Tilde => token::Tilde,