Make some matches exhaustive to avoid bugs, fix tools

compiler/rustc_ast_lowering/src/item.rs

@@ -1035,6 +1035,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let (Some(coroutine_kind), Some(body)) = (coroutine_kind, body) else {
             return self.lower_fn_body_block(span, decl, body);
         };
+        // FIXME(gen_blocks): Introduce `closure_id` method and remove ALL destructuring.
         let (CoroutineKind::Async { closure_id, .. }
         | CoroutineKind::Gen { closure_id, .. }
         | CoroutineKind::AsyncGen { closure_id, .. }) = coroutine_kind;

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1271,14 +1271,15 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
         // Functions cannot both be `const async` or `const gen`
         if let Some(&FnHeader {
             constness: Const::Yes(cspan),
-            coroutine_kind:
+            coroutine_kind: Some(coro_kind),
-                Some(
-                    CoroutineKind::Async { span: aspan, .. }
-                    | CoroutineKind::Gen { span: aspan, .. },
-                ),
             ..
         }) = fk.header()
         {
+            let aspan = match coro_kind {
+                CoroutineKind::Async { span: aspan, .. }
+                | CoroutineKind::Gen { span: aspan, .. }
+                | CoroutineKind::AsyncGen { span: aspan, .. } => aspan,
+            };
             // FIXME(gen_blocks): Report a different error for `const gen`
             self.err_handler().emit_err(errors::ConstAndAsync {
                 spans: vec![cspan, aspan],

compiler/rustc_builtin_macros/src/test.rs

@@ -541,12 +541,30 @@ fn check_test_signature(
         return Err(sd.emit_err(errors::TestBadFn { span: i.span, cause: span, kind: "unsafe" }));
     }
 
-    if let Some(ast::CoroutineKind::Async { span, .. }) = f.sig.header.coroutine_kind {
+    if let Some(coro_kind) = f.sig.header.coroutine_kind {
-        return Err(sd.emit_err(errors::TestBadFn { span: i.span, cause: span, kind: "async" }));
+        match coro_kind {
-    }
+            ast::CoroutineKind::Async { span, .. } => {
-
+                return Err(sd.emit_err(errors::TestBadFn {
-    if let Some(ast::CoroutineKind::Gen { span, .. }) = f.sig.header.coroutine_kind {
+                    span: i.span,
-        return Err(sd.emit_err(errors::TestBadFn { span: i.span, cause: span, kind: "gen" }));
+                    cause: span,
+                    kind: "async",
+                }));
+            }
+            ast::CoroutineKind::Gen { span, .. } => {
+                return Err(sd.emit_err(errors::TestBadFn {
+                    span: i.span,
+                    cause: span,
+                    kind: "gen",
+                }));
+            }
+            ast::CoroutineKind::AsyncGen { span, .. } => {
+                return Err(sd.emit_err(errors::TestBadFn {
+                    span: i.span,
+                    cause: span,
+                    kind: "async gen",
+                }));
+            }
+        }
     }
 
     // If the termination trait is active, the compiler will check that the output

compiler/rustc_lint/src/early.rs

@@ -162,11 +162,10 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
         // Explicitly check for lints associated with 'closure_id', since
         // it does not have a corresponding AST node
         if let ast_visit::FnKind::Fn(_, _, sig, _, _, _) = fk {
-            if let Some(
+            if let Some(coro_kind) = sig.header.coroutine_kind {
-                ast::CoroutineKind::Async { closure_id, .. }
+                let (ast::CoroutineKind::Async { closure_id, .. }
-                | ast::CoroutineKind::Gen { closure_id, .. },
+                | ast::CoroutineKind::Gen { closure_id, .. }
-            ) = sig.header.coroutine_kind
+                | ast::CoroutineKind::AsyncGen { closure_id, .. }) = coro_kind;
-            {
                 self.check_id(closure_id);
             }
         }
@@ -227,13 +226,13 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
         // it does not have a corresponding AST node
         match e.kind {
             ast::ExprKind::Closure(box ast::Closure {
-                coroutine_kind:
+                coroutine_kind: Some(coro_kind), ..
-                    Some(
+            }) => {
-                        ast::CoroutineKind::Async { closure_id, .. }
+                let (ast::CoroutineKind::Async { closure_id, .. }
-                        | ast::CoroutineKind::Gen { closure_id, .. },
+                | ast::CoroutineKind::Gen { closure_id, .. }
-                    ),
+                | ast::CoroutineKind::AsyncGen { closure_id, .. }) = coro_kind;
-                ..
+                self.check_id(closure_id);
-            }) => self.check_id(closure_id),
+            }
             _ => {}
         }
         lint_callback!(self, check_expr_post, e);

compiler/rustc_resolve/src/def_collector.rs

@@ -156,29 +156,33 @@ impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> {
 
     fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
         if let FnKind::Fn(_, _, sig, _, generics, body) = fn_kind {
-            if let Some(
+            match sig.header.coroutine_kind {
-                CoroutineKind::Async { closure_id, .. } | CoroutineKind::Gen { closure_id, .. },
+                Some(
-            ) = sig.header.coroutine_kind
+                    CoroutineKind::Async { closure_id, .. }
-            {
+                    | CoroutineKind::Gen { closure_id, .. }
-                self.visit_generics(generics);
+                    | CoroutineKind::AsyncGen { closure_id, .. },
+                ) => {
+                    self.visit_generics(generics);
 
-                // For async functions, we need to create their inner defs inside of a
+                    // For async functions, we need to create their inner defs inside of a
-                // closure to match their desugared representation. Besides that,
+                    // closure to match their desugared representation. Besides that,
-                // we must mirror everything that `visit::walk_fn` below does.
+                    // we must mirror everything that `visit::walk_fn` below does.
-                self.visit_fn_header(&sig.header);
+                    self.visit_fn_header(&sig.header);
-                for param in &sig.decl.inputs {
+                    for param in &sig.decl.inputs {
-                    self.visit_param(param);
+                        self.visit_param(param);
+                    }
+                    self.visit_fn_ret_ty(&sig.decl.output);
+                    // If this async fn has no body (i.e. it's an async fn signature in a trait)
+                    // then the closure_def will never be used, and we should avoid generating a
+                    // def-id for it.
+                    if let Some(body) = body {
+                        let closure_def =
+                            self.create_def(closure_id, kw::Empty, DefKind::Closure, span);
+                        self.with_parent(closure_def, |this| this.visit_block(body));
+                    }
+                    return;
                 }
-                self.visit_fn_ret_ty(&sig.decl.output);
+                None => {}
-                // If this async fn has no body (i.e. it's an async fn signature in a trait)
-                // then the closure_def will never be used, and we should avoid generating a
-                // def-id for it.
-                if let Some(body) = body {
-                    let closure_def =
-                        self.create_def(closure_id, kw::Empty, DefKind::Closure, span);
-                    self.with_parent(closure_def, |this| this.visit_block(body));
-                }
-                return;
             }
         }
 

src/tools/clippy/clippy_utils/src/ast_utils.rs

@@ -566,7 +566,8 @@ pub fn eq_fn_sig(l: &FnSig, r: &FnSig) -> bool {
 fn eq_opt_coroutine_kind(l: Option<CoroutineKind>, r: Option<CoroutineKind>) -> bool {
     match (l, r) {
         (Some(CoroutineKind::Async { .. }), Some(CoroutineKind::Async { .. }))
-        | (Some(CoroutineKind::Gen { .. }), Some(CoroutineKind::Gen { .. })) => true,
+        | (Some(CoroutineKind::Gen { .. }), Some(CoroutineKind::Gen { .. }))
+        | (Some(CoroutineKind::AsyncGen { .. }), Some(CoroutineKind::AsyncGen { .. })) => true,
         (None, None) => true,
         _ => false,
     }

src/tools/rustfmt/src/closures.rs

@@ -275,6 +275,7 @@ fn rewrite_closure_fn_decl(
     let coro = match coroutine_kind {
         Some(ast::CoroutineKind::Async { .. }) => "async ",
         Some(ast::CoroutineKind::Gen { .. }) => "gen ",
+        Some(ast::CoroutineKind::AsyncGen { .. }) => "async gen ",
         None => "",
     };
     let mover = if matches!(capture, ast::CaptureBy::Value { .. }) {

src/tools/rustfmt/src/utils.rs

@@ -79,6 +79,7 @@ pub(crate) fn format_coro(coroutine_kind: &ast::CoroutineKind) -> &'static str {
     match coroutine_kind {
         ast::CoroutineKind::Async { .. } => "async ",
         ast::CoroutineKind::Gen { .. } => "gen ",
+        ast::CoroutineKind::AsyncGen { .. } => "async gen ",
     }
 }