stabilize :pat2015, leave :pat2021 gated

Author: mark-i-m

compiler/rustc_expand/src/mbe/quoted.rs

@@ -62,19 +62,16 @@ pub(super) fn parse(
                                 Some((frag, _)) => {
                                     let span = token.span.with_lo(start_sp.lo());
 
-                                    match frag.name {
-                                        sym::pat2015 | sym::pat2021 => {
-                                            if !features.edition_macro_pats {
-                                                feature_err(
-                                                    sess,
-                                                    sym::edition_macro_pats,
-                                                    frag.span,
-                                                    "`pat2015` and `pat2021` are unstable.",
-                                                )
-                                                .emit();
-                                            }
-                                        }
-                                        _ => {}
+                                    if matches!(frag.name, sym::pat2021)
+                                        && !features.edition_macro_pats
+                                    {
+                                        feature_err(
+                                            sess,
+                                            sym::edition_macro_pats,
+                                            frag.span,
+                                            "`pat2021` is unstable.",
+                                        )
+                                        .emit();
                                     }
 
                                     let kind =

compiler/rustc_feature/src/active.rs

@@ -609,7 +609,7 @@ declare_features! (
     /// Allows arbitrary expressions in key-value attributes at parse time.
     (active, extended_key_value_attributes, "1.50.0", Some(78835), None),
 
-    /// `:pat2015` and `:pat2021` macro matchers.
+    /// `:pat2021` macro matcher.
     (active, edition_macro_pats, "1.51.0", Some(54883), None),
 
     /// Allows const generics to have default values (e.g. `struct Foo<const N: usize = 3>(...);`).

src/test/ui/feature-gates/feature-gate-edition_macro_pats.rs

@@ -1,8 +1,8 @@
 // Feature gate test for `edition_macro_pats` feature.
 
 macro_rules! foo {
-    ($x:pat2015) => {}; //~ERROR `pat2015` and `pat2021` are unstable
-    ($x:pat2021) => {}; //~ERROR `pat2015` and `pat2021` are unstable
+    ($x:pat2015) => {}; // ok
+    ($x:pat2021) => {}; //~ERROR `pat2021` is unstable
 }
 
 fn main() {}

src/test/ui/feature-gates/feature-gate-edition_macro_pats.stderr

@@ -1,13 +1,4 @@
-error[E0658]: `pat2015` and `pat2021` are unstable.
-  --> $DIR/feature-gate-edition_macro_pats.rs:4:9
-   |
-LL |     ($x:pat2015) => {};
-   |         ^^^^^^^
-   |
-   = note: see issue #54883 <https://github.com/rust-lang/rust/issues/54883> for more information
-   = help: add `#![feature(edition_macro_pats)]` to the crate attributes to enable
-
-error[E0658]: `pat2015` and `pat2021` are unstable.
+error[E0658]: `pat2021` is unstable.
   --> $DIR/feature-gate-edition_macro_pats.rs:5:9
    |
 LL |     ($x:pat2021) => {};
@@ -16,6 +7,6 @@ LL |     ($x:pat2021) => {};
    = note: see issue #54883 <https://github.com/rust-lang/rust/issues/54883> for more information
    = help: add `#![feature(edition_macro_pats)]` to the crate attributes to enable
 
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0658`.