From 2db0dc32970a70bcf622e0854c944753a065cb15 Mon Sep 17 00:00:00 2001
From: Arpad Borsos <swatinem@swatinem.de>
Date: Sat, 26 Nov 2022 21:33:12 +0100
Subject: [PATCH] Simplify checking for `GeneratorKind::Async`
Adds a helper method around `generator_kind` that makes matching async constructs simpler.
---
.../rustc_borrowck/src/diagnostics/region_errors.rs | 7 +------
compiler/rustc_lint/src/unused.rs | 5 +----
compiler/rustc_middle/src/ty/context.rs | 5 +++++
.../src/traits/error_reporting/suggestions.rs | 11 ++---------
.../src/traits/select/candidate_assembly.rs | 4 +---
5 files changed, 10 insertions(+), 22 deletions(-)
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index 534675f1dc0..7aa099433a7 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -514,12 +514,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
span: *span,
ty_err: match output_ty.kind() {
ty::Closure(_, _) => FnMutReturnTypeErr::ReturnClosure { span: *span },
- ty::Generator(def, ..)
- if matches!(
- self.infcx.tcx.generator_kind(def),
- Some(hir::GeneratorKind::Async(_))
- ) =>
- {
+ ty::Generator(def, ..) if self.infcx.tcx.generator_is_async(*def) => {
FnMutReturnTypeErr::ReturnAsyncBlock { span: *span }
}
_ => FnMutReturnTypeErr::ReturnRef { span: *span },
diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs
index 43864ed45fa..88ad4c67d93 100644
--- a/compiler/rustc_lint/src/unused.rs
+++ b/compiler/rustc_lint/src/unused.rs
@@ -322,10 +322,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
ty::Closure(..) => Some(MustUsePath::Closure(span)),
ty::Generator(def_id, ..) => {
// async fn should be treated as "implementor of `Future`"
- let must_use = if matches!(
- cx.tcx.generator_kind(def_id),
- Some(hir::GeneratorKind::Async(..))
- ) {
+ let must_use = if cx.tcx.generator_is_async(def_id) {
let def_id = cx.tcx.lang_items().future_trait().unwrap();
is_def_must_use(cx, def_id, span)
.map(|inner| MustUsePath::Opaque(Box::new(inner)))
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index bf30a403d9b..1628cca638e 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -1360,6 +1360,11 @@ impl<'tcx> TyCtxt<'tcx> {
self.diagnostic_items(did.krate).name_to_id.get(&name) == Some(&did)
}
+ /// Returns `true` if the node pointed to by `def_id` is a generator for an async construct.
+ pub fn generator_is_async(self, def_id: DefId) -> bool {
+ matches!(self.generator_kind(def_id), Some(hir::GeneratorKind::Async(_)))
+ }
+
pub fn stability(self) -> &'tcx stability::Index {
self.stability_index(())
}
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index 992ea175516..eeb4693eec3 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -1988,11 +1988,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
.as_local()
.and_then(|def_id| hir.maybe_body_owned_by(def_id))
.map(|body_id| hir.body(body_id));
- let is_async = self
- .tcx
- .generator_kind(generator_did)
- .map(|generator_kind| matches!(generator_kind, hir::GeneratorKind::Async(..)))
- .unwrap_or(false);
let mut visitor = AwaitsVisitor::default();
if let Some(body) = generator_body {
visitor.visit_body(body);
@@ -2069,6 +2064,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
debug!(?interior_or_upvar_span);
if let Some(interior_or_upvar_span) = interior_or_upvar_span {
+ let is_async = self.tcx.generator_is_async(generator_did);
let typeck_results = match generator_data {
GeneratorData::Local(typeck_results) => Some(typeck_results),
GeneratorData::Foreign(_) => None,
@@ -2641,10 +2637,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
if is_future
&& obligated_types.last().map_or(false, |ty| match ty.kind() {
ty::Generator(last_def_id, ..) => {
- matches!(
- tcx.generator_kind(last_def_id),
- Some(GeneratorKind::Async(..))
- )
+ tcx.generator_is_async(*last_def_id)
}
_ => false,
})
diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
index 10854ede652..627ed4674b0 100644
--- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
@@ -430,9 +430,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
) {
let self_ty = obligation.self_ty().skip_binder();
if let ty::Generator(did, ..) = self_ty.kind() {
- if let Some(rustc_hir::GeneratorKind::Async(_generator_kind)) =
- self.tcx().generator_kind(did)
- {
+ if self.tcx().generator_is_async(*did) {
debug!(?self_ty, ?obligation, "assemble_future_candidates",);
candidates.vec.push(FutureCandidate);