Auto merge of #83386 - mark-i-m:stabilize-pat2015, r=nikomatsakis

Stabilize `:pat_param` and remove `:pat2021`

Blocked on #83384

cc `@rust-lang/lang` #79278

If I understand `@nikomatsakis` in  https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/or.20patterns/near/231133873, another FCP is not needed.

r? `@nikomatsakis`

1 files changed, 8 insertions, 6 deletions

diff --git a/compiler/rustc_parse/src/parser/nonterminal.rs b/compiler/rustc_parse/src/parser/nonterminal.rs
index 5c4a2785d6e..0c43e304f1e 100644
--- a/compiler/rustc_parse/src/parser/nonterminal.rs
+++ b/compiler/rustc_parse/src/parser/nonterminal.rs
@@ -61,7 +61,8 @@ impl<'a> Parser<'a> {
                 },
                 _ => false,
             },
-            NonterminalKind::Pat2015 { .. } | NonterminalKind::Pat2021 { .. } => match token.kind {
+            NonterminalKind::PatParam { .. } | NonterminalKind::PatWithOr { .. } => {
+                match token.kind {
                 token::Ident(..) |                  // box, ref, mut, and other identifiers (can stricten)
                 token::OpenDelim(token::Paren) |    // tuple pattern
                 token::OpenDelim(token::Bracket) |  // slice pattern
@@ -75,10 +76,11 @@ impl<'a> Parser<'a> {
                 token::Lt |                         // path (UFCS constant)
                 token::BinOp(token::Shl) => true,   // path (double UFCS)
                 // leading vert `|` or-pattern
-                token::BinOp(token::Or) =>  matches!(kind, NonterminalKind::Pat2021 {..}),
+                token::BinOp(token::Or) =>  matches!(kind, NonterminalKind::PatWithOr {..}),
                 token::Interpolated(ref nt) => may_be_ident(nt),
                 _ => false,
-            },
+            }
+            }
             NonterminalKind::Lifetime => match token.kind {
                 token::Lifetime(_) => true,
                 token::Interpolated(ref nt) => {
@@ -118,10 +120,10 @@ impl<'a> Parser<'a> {
                     return Err(self.struct_span_err(self.token.span, "expected a statement"));
                 }
             },
-            NonterminalKind::Pat2015 { .. } | NonterminalKind::Pat2021 { .. } => {
+            NonterminalKind::PatParam { .. } | NonterminalKind::PatWithOr { .. } => {
                 token::NtPat(self.collect_tokens_no_attrs(|this| match kind {
-                    NonterminalKind::Pat2015 { .. } => this.parse_pat_no_top_alt(None),
-                    NonterminalKind::Pat2021 { .. } => {
+                    NonterminalKind::PatParam { .. } => this.parse_pat_no_top_alt(None),
+                    NonterminalKind::PatWithOr { .. } => {
                         this.parse_pat_allow_top_alt(None, RecoverComma::No)
                     }
                     _ => unreachable!(),