diff options
Diffstat (limited to 'compiler/rustc_lint/src/unused.rs')
| -rw-r--r-- | compiler/rustc_lint/src/unused.rs | 71 |
1 files changed, 47 insertions, 24 deletions
diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs index 5015b751e..6041f8075 100644 --- a/compiler/rustc_lint/src/unused.rs +++ b/compiler/rustc_lint/src/unused.rs @@ -94,7 +94,9 @@ declare_lint_pass!(UnusedResults => [UNUSED_MUST_USE, UNUSED_RESULTS]); impl<'tcx> LateLintPass<'tcx> for UnusedResults { fn check_stmt(&mut self, cx: &LateContext<'_>, s: &hir::Stmt<'_>) { - let hir::StmtKind::Semi(mut expr) = s.kind else { return; }; + let hir::StmtKind::Semi(mut expr) = s.kind else { + return; + }; let mut expr_is_from_block = false; while let hir::ExprKind::Block(blk, ..) = expr.kind @@ -284,22 +286,25 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { } ty::Adt(def, _) => is_def_must_use(cx, def.did(), span), ty::Alias(ty::Opaque, ty::AliasTy { def_id: def, .. }) => { - elaborate(cx.tcx, cx.tcx.explicit_item_bounds(def).subst_identity_iter_copied()) - // We only care about self bounds for the impl-trait - .filter_only_self() - .find_map(|(pred, _span)| { - // We only look at the `DefId`, so it is safe to skip the binder here. - if let ty::ClauseKind::Trait(ref poly_trait_predicate) = - pred.kind().skip_binder() - { - let def_id = poly_trait_predicate.trait_ref.def_id; - - is_def_must_use(cx, def_id, span) - } else { - None - } - }) - .map(|inner| MustUsePath::Opaque(Box::new(inner))) + elaborate( + cx.tcx, + cx.tcx.explicit_item_bounds(def).instantiate_identity_iter_copied(), + ) + // We only care about self bounds for the impl-trait + .filter_only_self() + .find_map(|(pred, _span)| { + // We only look at the `DefId`, so it is safe to skip the binder here. + if let ty::ClauseKind::Trait(ref poly_trait_predicate) = + pred.kind().skip_binder() + { + let def_id = poly_trait_predicate.trait_ref.def_id; + + is_def_must_use(cx, def_id, span) + } else { + None + } + }) + .map(|inner| MustUsePath::Opaque(Box::new(inner))) } ty::Dynamic(binders, _, _) => binders.iter().find_map(|predicate| { if let ty::ExistentialPredicate::Trait(ref trait_ref) = predicate.skip_binder() @@ -409,7 +414,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { match path { MustUsePath::Suppressed => {} MustUsePath::Boxed(path) => { - let descr_pre = &format!("{}boxed ", descr_pre); + let descr_pre = &format!("{descr_pre}boxed "); emit_must_use_untranslated( cx, path, @@ -421,7 +426,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { ); } MustUsePath::Opaque(path) => { - let descr_pre = &format!("{}implementer{} of ", descr_pre, plural_suffix); + let descr_pre = &format!("{descr_pre}implementer{plural_suffix} of "); emit_must_use_untranslated( cx, path, @@ -433,7 +438,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { ); } MustUsePath::TraitObject(path) => { - let descr_post = &format!(" trait object{}{}", plural_suffix, descr_post); + let descr_post = &format!(" trait object{plural_suffix}{descr_post}"); emit_must_use_untranslated( cx, path, @@ -446,7 +451,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { } MustUsePath::TupleElement(elems) => { for (index, path) in elems { - let descr_post = &format!(" in tuple element {}", index); + let descr_post = &format!(" in tuple element {index}"); emit_must_use_untranslated( cx, path, @@ -459,7 +464,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults { } } MustUsePath::Array(path, len) => { - let descr_pre = &format!("{}array{} of ", descr_pre, plural_suffix); + let descr_pre = &format!("{descr_pre}array{plural_suffix} of "); emit_must_use_untranslated( cx, path, @@ -648,7 +653,7 @@ trait UnusedDelimLint { ExprKind::Call(fn_, _params) => fn_, ExprKind::Cast(expr, _ty) => expr, ExprKind::Type(expr, _ty) => expr, - ExprKind::Index(base, _subscript) => base, + ExprKind::Index(base, _subscript, _) => base, _ => break, }; if !classify::expr_requires_semi_to_be_stmt(innermost) { @@ -661,6 +666,24 @@ trait UnusedDelimLint { if !followed_by_block { return false; } + + // Check if we need parens for `match &( Struct { feild: }) {}`. + { + let mut innermost = inner; + loop { + innermost = match &innermost.kind { + ExprKind::AddrOf(_, _, expr) => expr, + _ => { + if parser::contains_exterior_struct_lit(&innermost) { + return true; + } else { + break; + } + } + } + } + } + let mut innermost = inner; loop { innermost = match &innermost.kind { @@ -825,7 +848,7 @@ trait UnusedDelimLint { (value, UnusedDelimsCtx::ReturnValue, false, Some(left), None, true) } - Index(_, ref value) => (value, UnusedDelimsCtx::IndexExpr, false, None, None, false), + Index(_, ref value, _) => (value, UnusedDelimsCtx::IndexExpr, false, None, None, false), Assign(_, ref value, _) | AssignOp(.., ref value) => { (value, UnusedDelimsCtx::AssignedValue, false, None, None, false) |