Use assert_matches around the compiler

compiler/rustc_parse/src/lib.rs

@@ -5,6 +5,7 @@
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
 #![feature(array_windows)]
+#![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(debug_closure_helpers)]
 #![feature(if_let_guard)]

compiler/rustc_parse/src/parser/mod.rs

@@ -10,6 +10,7 @@ mod path;
 mod stmt;
 mod ty;
 
+use std::assert_matches::debug_assert_matches;
 use std::ops::Range;
 use std::{fmt, mem, slice};
 
@@ -1385,7 +1386,7 @@ impl<'a> Parser<'a> {
                     // can capture these tokens if necessary.
                     self.bump();
                     if self.token_cursor.stack.len() == target_depth {
-                        debug_assert!(matches!(self.token.kind, token::CloseDelim(_)));
+                        debug_assert_matches!(self.token.kind, token::CloseDelim(_));
                         break;
                     }
                 }

compiler/rustc_parse/src/parser/tests.rs

@@ -1,3 +1,4 @@
+use std::assert_matches::assert_matches;
 use std::io::prelude::*;
 use std::iter::Peekable;
 use std::path::{Path, PathBuf};
@@ -1747,7 +1748,7 @@ fn out_of_line_mod() {
         .unwrap();
 
         let ast::ItemKind::Mod(_, mod_kind) = &item.kind else { panic!() };
-        assert!(matches!(mod_kind, ast::ModKind::Loaded(items, ..) if items.len() == 2));
+        assert_matches!(mod_kind, ast::ModKind::Loaded(items, ..) if items.len() == 2);
     });
 }