Port #[rustc_lint_opt_deny_field_access] to attribute parser

Author: Bryntet

compiler/rustc_attr_parsing/src/attributes/rustc_internal.rs

@@ -117,6 +117,30 @@ impl<S: Stage> SingleAttributeParser<S> for RustcLegacyConstGenericsParser {
     }
 }
 
+pub(crate) struct RustcLintOptDenyFieldAccessParser;
+
+impl<S: Stage> SingleAttributeParser<S> for RustcLintOptDenyFieldAccessParser {
+    const PATH: &[Symbol] = &[sym::rustc_lint_opt_deny_field_access];
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepInnermost;
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::Field)]);
+    const TEMPLATE: AttributeTemplate = template!(Word);
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser) -> Option<AttributeKind> {
+        let Some(arg) = args.list().and_then(MetaItemListParser::single) else {
+            cx.expected_single_argument(cx.attr_span);
+            return None;
+        };
+
+        let MetaItemOrLitParser::Lit(MetaItemLit { kind: LitKind::Str(lint_message, _), .. }) = arg
+        else {
+            cx.expected_string_literal(arg.span(), arg.lit());
+            return None;
+        };
+
+        Some(AttributeKind::RustcLintOptDenyFieldAccess { lint_message: *lint_message })
+    }
+}
+
 pub(crate) struct RustcLintOptTyParser;
 
 impl<S: Stage> NoArgsAttributeParser<S> for RustcLintOptTyParser {

compiler/rustc_attr_parsing/src/context.rs

@@ -61,9 +61,9 @@ use crate::attributes::prototype::CustomMirParser;
 use crate::attributes::repr::{AlignParser, AlignStaticParser, ReprParser};
 use crate::attributes::rustc_internal::{
     RustcLayoutScalarValidRangeEndParser, RustcLayoutScalarValidRangeStartParser,
-    RustcLegacyConstGenericsParser, RustcLintOptTyParser, RustcLintQueryInstabilityParser,
-    RustcMainParser, RustcNeverReturnsNullPointerParser, RustcNoImplicitAutorefsParser,
-    RustcObjectLifetimeDefaultParser, RustcScalableVectorParser,
+    RustcLegacyConstGenericsParser, RustcLintOptDenyFieldAccessParser, RustcLintOptTyParser,
+    RustcLintQueryInstabilityParser, RustcMainParser, RustcNeverReturnsNullPointerParser,
+    RustcNoImplicitAutorefsParser, RustcObjectLifetimeDefaultParser, RustcScalableVectorParser,
     RustcSimdMonomorphizeLaneLimitParser,
 };
 use crate::attributes::semantics::MayDangleParser;
@@ -213,6 +213,7 @@ attribute_parsers!(
         Single<RustcLayoutScalarValidRangeEndParser>,
         Single<RustcLayoutScalarValidRangeStartParser>,
         Single<RustcLegacyConstGenericsParser>,
+        Single<RustcLintOptDenyFieldAccessParser>,
         Single<RustcObjectLifetimeDefaultParser>,
         Single<RustcScalableVectorParser>,
         Single<RustcSimdMonomorphizeLaneLimitParser>,

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -931,6 +931,9 @@ pub enum AttributeKind {
     /// Represents `#[rustc_legacy_const_generics]`
     RustcLegacyConstGenerics { fn_indexes: ThinVec<(usize, Span)>, attr_span: Span },
 
+    /// Represents `#[rustc_lint_opt_deny_field_access]`
+    RustcLintOptDenyFieldAccess { lint_message: Symbol },
+
     /// Represents `#[rustc_lint_opt_ty]`
     RustcLintOptTy,
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -94,6 +94,7 @@ impl AttributeKind {
             RustcLayoutScalarValidRangeEnd(..) => Yes,
             RustcLayoutScalarValidRangeStart(..) => Yes,
             RustcLegacyConstGenerics { .. } => Yes,
+            RustcLintOptDenyFieldAccess { .. } => Yes,
             RustcLintOptTy => Yes,
             RustcLintQueryInstability => Yes,
             RustcMain => No,

compiler/rustc_lint/src/internal.rs

@@ -668,17 +668,12 @@ impl LateLintPass<'_> for BadOptAccess {
 
         for field in adt_def.all_fields() {
             if field.name == target.name
-                && let Some(attr) =
-                    cx.tcx.get_attr(field.did, sym::rustc_lint_opt_deny_field_access)
-                && let Some(items) = attr.meta_item_list()
-                && let Some(item) = items.first()
-                && let Some(lit) = item.lit()
-                && let ast::LitKind::Str(val, _) = lit.kind
+                && let Some(lint_message) = find_attr!(cx.tcx.get_all_attrs(field.did), AttributeKind::RustcLintOptDenyFieldAccess { lint_message, } => lint_message)
             {
                 cx.emit_span_lint(
                     BAD_OPT_ACCESS,
                     expr.span,
-                    BadOptAccessDiag { msg: val.as_str() },
+                    BadOptAccessDiag { msg: lint_message.as_str() },
                 );
             }
         }

compiler/rustc_passes/messages.ftl

@@ -473,9 +473,6 @@ passes_rustc_legacy_const_generics_only =
     #[rustc_legacy_const_generics] functions must only have const generics
     .label = non-const generic parameter
 
-passes_rustc_lint_opt_deny_field_access =
-    `#[rustc_lint_opt_deny_field_access]` should be applied to a field
-    .label = not a field
 
 passes_rustc_pub_transparent =
     attribute should be applied to `#[repr(transparent)]` types

compiler/rustc_passes/src/check_attr.rs

@@ -258,6 +258,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | AttributeKind::RustcNoImplicitAutorefs
                     | AttributeKind::RustcLayoutScalarValidRangeStart(..)
                     | AttributeKind::RustcLayoutScalarValidRangeEnd(..)
+                    | AttributeKind::RustcLintOptDenyFieldAccess { .. }
                     | AttributeKind::RustcLintOptTy
                     | AttributeKind::RustcLintQueryInstability
                     | AttributeKind::RustcNeverReturnsNullPointer
@@ -314,9 +315,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                         [sym::rustc_lint_diagnostics, ..] => {
                             self.check_applied_to_fn_or_method(hir_id, attr.span(), span, target)
                         }
-                        [sym::rustc_lint_opt_deny_field_access, ..] => {
-                            self.check_rustc_lint_opt_deny_field_access(attr, span, target)
-                        }
                         [sym::rustc_clean, ..]
                         | [sym::rustc_dirty, ..]
                         | [sym::rustc_if_this_changed, ..]
@@ -1251,18 +1249,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         }
     }
 
-    /// Checks that the `#[rustc_lint_opt_deny_field_access]` attribute is only applied to a field.
-    fn check_rustc_lint_opt_deny_field_access(&self, attr: &Attribute, span: Span, target: Target) {
-        match target {
-            Target::Field => {}
-            _ => {
-                self.tcx
-                    .dcx()
-                    .emit_err(errors::RustcLintOptDenyFieldAccess { attr_span: attr.span(), span });
-            }
-        }
-    }
-
     /// Checks that the dep-graph debugging attributes are only present when the query-dep-graph
     /// option is passed to the compiler.
     fn check_rustc_dirty_clean(&self, attr: &Attribute) {

compiler/rustc_passes/src/errors.rs

@@ -412,15 +412,6 @@ pub(crate) struct UnusedMultiple {
     pub name: Symbol,
 }
 
-#[derive(Diagnostic)]
-#[diag(passes_rustc_lint_opt_deny_field_access)]
-pub(crate) struct RustcLintOptDenyFieldAccess {
-    #[primary_span]
-    pub attr_span: Span,
-    #[label]
-    pub span: Span,
-}
-
 #[derive(Diagnostic)]
 #[diag(passes_collapse_debuginfo)]
 pub(crate) struct CollapseDebuginfo {