drive-by: Add is_async fn to hir::IsAsync

compiler/rustc_const_eval/src/transform/check_consts/mod.rs

@@ -62,7 +62,7 @@ impl<'mir, 'tcx> ConstCx<'mir, 'tcx> {
     }
 
     fn is_async(&self) -> bool {
-        self.tcx.asyncness(self.def_id()) == hir::IsAsync::Async
+        self.tcx.asyncness(self.def_id()).is_async()
     }
 }
 

compiler/rustc_hir/src/hir.rs

@@ -2720,6 +2720,12 @@ pub enum IsAsync {
     NotAsync,
 }
 
+impl IsAsync {
+    pub fn is_async(self) -> bool {
+        self == IsAsync::Async
+    }
+}
+
 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, Encodable, Decodable, HashStable_Generic)]
 pub enum Defaultness {
     Default { has_value: bool },

compiler/rustc_hir_analysis/src/check/compare_method.rs

@@ -688,9 +688,7 @@ fn report_trait_method_mismatch<'tcx>(
                 // Suggestion to change output type. We do not suggest in `async` functions
                 // to avoid complex logic or incorrect output.
                 match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind {
-                    ImplItemKind::Fn(ref sig, _)
+                    ImplItemKind::Fn(ref sig, _) if !sig.header.asyncness.is_async() => {
-                        if sig.header.asyncness == hir::IsAsync::NotAsync =>
-                    {
                         let msg = "change the output type to match the trait";
                         let ap = Applicability::MachineApplicable;
                         match sig.decl.output {

src/tools/clippy/clippy_lints/src/manual_async_fn.rs

@@ -6,7 +6,7 @@ use rustc_errors::Applicability;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{
     AsyncGeneratorKind, Block, Body, Closure, Expr, ExprKind, FnDecl, FnRetTy, GeneratorKind, GenericArg, GenericBound,
-    HirId, IsAsync, ItemKind, LifetimeName, Term, TraitRef, Ty, TyKind, TypeBindingKind,
+    HirId, ItemKind, LifetimeName, Term, TraitRef, Ty, TyKind, TypeBindingKind,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -49,7 +49,7 @@ impl<'tcx> LateLintPass<'tcx> for ManualAsyncFn {
     ) {
         if_chain! {
             if let Some(header) = kind.header();
-            if header.asyncness == IsAsync::NotAsync;
+            if !header.asyncness.is_async();
             // Check that this function returns `impl Future`
             if let FnRetTy::Return(ret_ty) = decl.output;
             if let Some((trait_ref, output_lifetimes)) = future_trait_ref(cx, ret_ty);

src/tools/clippy/clippy_lints/src/unused_async.rs

@@ -1,6 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_help;
 use rustc_hir::intravisit::{walk_expr, walk_fn, FnKind, Visitor};
-use rustc_hir::{Body, Expr, ExprKind, FnDecl, HirId, IsAsync, YieldSource};
+use rustc_hir::{Body, Expr, ExprKind, FnDecl, HirId, YieldSource};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -68,7 +68,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedAsync {
         span: Span,
         hir_id: HirId,
     ) {
-        if !span.from_expansion() && fn_kind.asyncness() == IsAsync::Async {
+        if !span.from_expansion() && fn_kind.asyncness().is_async() {
             let mut visitor = AsyncFnVisitor { cx, found_await: false };
             walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), hir_id);
             if !visitor.found_await {

src/tools/clippy/clippy_utils/src/lib.rs

@@ -87,10 +87,10 @@ use rustc_hir::hir_id::{HirIdMap, HirIdSet};
 use rustc_hir::intravisit::{walk_expr, FnKind, Visitor};
 use rustc_hir::LangItem::{OptionNone, ResultErr, ResultOk};
 use rustc_hir::{
-    def, Arm, ArrayLen, BindingAnnotation, Block, BlockCheckMode, Body, Closure, Constness, Destination, Expr,
+    def, Arm, ArrayLen, BindingAnnotation, Block, BlockCheckMode, Body, Closure, Constness,
-    ExprKind, FnDecl, HirId, Impl, ImplItem, ImplItemKind, IsAsync, Item, ItemKind, LangItem, Local, MatchSource,
+    Destination, Expr, ExprKind, FnDecl, HirId, Impl, ImplItem, ImplItemKind, Item, ItemKind,
-    Mutability, Node, Param, Pat, PatKind, Path, PathSegment, PrimTy, QPath, Stmt, StmtKind, TraitItem, TraitItemKind,
+    LangItem, Local, MatchSource, Mutability, Node, Param, Pat, PatKind, Path, PathSegment, PrimTy,
-    TraitRef, TyKind, UnOp,
+    QPath, Stmt, StmtKind, TraitItem, TraitItemKind, TraitRef, TyKind, UnOp,
 };
 use rustc_lexer::{tokenize, TokenKind};
 use rustc_lint::{LateContext, Level, Lint, LintContext};
@@ -1861,7 +1861,7 @@ pub fn if_sequence<'tcx>(mut expr: &'tcx Expr<'tcx>) -> (Vec<&'tcx Expr<'tcx>>,
 
 /// Checks if the given function kind is an async function.
 pub fn is_async_fn(kind: FnKind<'_>) -> bool {
-    matches!(kind, FnKind::ItemFn(_, _, header) if header.asyncness == IsAsync::Async)
+    matches!(kind, FnKind::ItemFn(_, _, header) if header.asyncness.is_async())
 }
 
 /// Peels away all the compiler generated code surrounding the body of an async function,