Port #[macro_export] to the new attribute parsing infrastructure

Author: Periodic1911

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -367,6 +367,9 @@ pub enum AttributeKind {
     /// Represents `#[macro_escape]`.
     MacroEscape(Span),
 
+    /// Represents [`#[macro_export}`](https://doc.rust-lang.org/reference/macros-by-example.html#r-macro.decl.scope.path).
+    MacroExport { span: Span, local_inner_macros: bool },
+
     /// Represents `#[rustc_macro_transparency]`.
     MacroTransparency(Transparency),
 

compiler/rustc_attr_data_structures/src/encode_cross_crate.rs

@@ -46,6 +46,7 @@ impl AttributeKind {
             LinkSection { .. } => Yes, // Needed for rustdoc
             LoopMatch(..) => No,
             MacroEscape(..) => No,
+            MacroExport { .. } => Yes,
             MacroTransparency(..) => Yes,
             MacroUse { .. } => No,
             Marker(..) => No,

compiler/rustc_attr_data_structures/src/lints.rs

@@ -10,7 +10,21 @@ pub struct AttributeLint<Id> {
 
 #[derive(Clone, Debug, HashStable_Generic)]
 pub enum AttributeLintKind {
-    UnusedDuplicate { this: Span, other: Span, warning: bool },
-    IllFormedAttributeInput { suggestions: Vec<String> },
-    EmptyAttribute { first_span: Span },
+    UnusedDuplicate {
+        this: Span,
+        other: Span,
+        warning: bool,
+    },
+    IllFormedAttributeInput {
+        suggestions: Vec<String>,
+    },
+    EmptyAttribute {
+        first_span: Span,
+    },
+    /// Copy of `IllFormedAttributeInput`
+    /// specifically for the `invalid_macro_export_arguments` lint until that is removed,
+    /// see <https://github.com/rust-lang/rust/pull/143857#issuecomment-3079175663>
+    InvalidMacroExportArguments {
+        suggestions: Vec<String>,
+    },
 }

compiler/rustc_attr_parsing/messages.ftl

@@ -32,6 +32,11 @@ attr_parsing_ill_formed_attribute_input = {$num_suggestions ->
         *[other] valid forms for the attribute are {$suggestions}
     }
 
+attr_parsing_invalid_macro_export_arguments = {$num_suggestions ->
+        [1] attribute must be of the form {$suggestions}
+        *[other] valid forms for the attribute are {$suggestions}
+    }
+
 attr_parsing_incorrect_repr_format_align_one_arg =
     incorrect `repr(align)` attribute format: `align` takes exactly one argument in parentheses
 

compiler/rustc_attr_parsing/src/attributes/macro_attrs.rs

@@ -1,10 +1,15 @@
+use rustc_attr_data_structures::AttributeKind::MacroExport;
+use rustc_attr_data_structures::lints::AttributeLintKind;
 use rustc_attr_data_structures::{AttributeKind, MacroUseArgs};
 use rustc_errors::DiagArgValue;
 use rustc_feature::{AttributeTemplate, template};
 use rustc_span::{Span, Symbol, sym};
 use thin_vec::ThinVec;
 
-use crate::attributes::{AcceptMapping, AttributeParser, NoArgsAttributeParser, OnDuplicate};
+use crate::attributes::{
+    AcceptMapping, AttributeOrder, AttributeParser, NoArgsAttributeParser, OnDuplicate,
+    SingleAttributeParser,
+};
 use crate::context::{AcceptContext, FinalizeContext, Stage};
 use crate::parser::ArgParser;
 use crate::session_diagnostics;
@@ -113,3 +118,58 @@ impl<S: Stage> AttributeParser<S> for MacroUseParser {
         Some(AttributeKind::MacroUse { span: self.first_span?, arguments: self.state })
     }
 }
+
+pub(crate) struct MacroExportParser;
+
+impl<S: Stage> SingleAttributeParser<S> for crate::attributes::macro_attrs::MacroExportParser {
+    const PATH: &[Symbol] = &[sym::macro_export];
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepOutermost;
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
+    const TEMPLATE: AttributeTemplate = template!(Word, List: "local_inner_macros");
+
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
+        let suggestions =
+            || <Self as SingleAttributeParser<S>>::TEMPLATE.suggestions(false, "macro_export");
+        let local_inner_macros = match args {
+            ArgParser::NoArgs => false,
+            ArgParser::List(list) => {
+                let Some(l) = list.single() else {
+                    let span = cx.attr_span;
+                    cx.emit_lint(
+                        AttributeLintKind::InvalidMacroExportArguments {
+                            suggestions: suggestions(),
+                        },
+                        span,
+                    );
+                    return None;
+                };
+                match l.meta_item().and_then(|i| i.path().word_sym()) {
+                    Some(sym::local_inner_macros) => true,
+                    _ => {
+                        let span = cx.attr_span;
+                        cx.emit_lint(
+                            AttributeLintKind::InvalidMacroExportArguments {
+                                suggestions: suggestions(),
+                            },
+                            span,
+                        );
+                        return None;
+                    }
+                }
+            }
+            ArgParser::NameValue(_) => {
+                let span = cx.attr_span;
+                let suggestions = suggestions();
+                cx.emit_err(session_diagnostics::IllFormedAttributeInputLint {
+                    num_suggestions: suggestions.len(),
+                    suggestions: DiagArgValue::StrListSepByAnd(
+                        suggestions.into_iter().map(|s| format!("`{s}`").into()).collect(),
+                    ),
+                    span,
+                });
+                return None;
+            }
+        };
+        Some(MacroExport { span: cx.attr_span, local_inner_macros })
+    }
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -33,7 +33,7 @@ use crate::attributes::lint_helpers::{
     AsPtrParser, AutomaticallyDerivedParser, PassByValueParser, PubTransparentParser,
 };
 use crate::attributes::loop_match::{ConstContinueParser, LoopMatchParser};
-use crate::attributes::macro_attrs::{MacroEscapeParser, MacroUseParser};
+use crate::attributes::macro_attrs::{MacroEscapeParser, MacroExportParser, MacroUseParser};
 use crate::attributes::must_use::MustUseParser;
 use crate::attributes::no_implicit_prelude::NoImplicitPreludeParser;
 use crate::attributes::non_exhaustive::NonExhaustiveParser;
@@ -154,6 +154,7 @@ attribute_parsers!(
         Single<LinkNameParser>,
         Single<LinkOrdinalParser>,
         Single<LinkSectionParser>,
+        Single<MacroExportParser>,
         Single<MustUseParser>,
         Single<OptimizeParser>,
         Single<PathAttributeParser>,

compiler/rustc_attr_parsing/src/lints.rs

@@ -34,5 +34,17 @@ pub fn emit_attribute_lint<L: LintEmitter>(lint: &AttributeLint<HirId>, lint_emi
             *first_span,
             session_diagnostics::EmptyAttributeList { attr_span: *first_span },
         ),
+        AttributeLintKind::InvalidMacroExportArguments { suggestions } => lint_emitter
+            .emit_node_span_lint(
+                rustc_session::lint::builtin::INVALID_MACRO_EXPORT_ARGUMENTS,
+                *id,
+                *span,
+                session_diagnostics::IllFormedAttributeInput {
+                    num_suggestions: suggestions.len(),
+                    suggestions: DiagArgValue::StrListSepByAnd(
+                        suggestions.into_iter().map(|s| format!("`{s}`").into()).collect(),
+                    ),
+                },
+            ),
     }
 }

compiler/rustc_expand/src/base.rs

@@ -909,9 +909,9 @@ impl SyntaxExtension {
         let allow_internal_unsafe =
             ast::attr::find_by_name(attrs, sym::allow_internal_unsafe).is_some();
 
-        let local_inner_macros = ast::attr::find_by_name(attrs, sym::macro_export)
-            .and_then(|macro_export| macro_export.meta_item_list())
-            .is_some_and(|l| ast::attr::list_contains_name(&l, sym::local_inner_macros));
+        let local_inner_macros =
+            *find_attr!(attrs, AttributeKind::MacroExport {local_inner_macros: l, ..} => l)
+                .unwrap_or(&false);
         let collapse_debuginfo = Self::get_collapse_debuginfo(sess, attrs, !is_local);
         tracing::debug!(?name, ?local_inner_macros, ?collapse_debuginfo, ?allow_internal_unsafe);
 

compiler/rustc_lint/src/non_local_def.rs

@@ -1,11 +1,12 @@
+use rustc_attr_data_structures::{AttributeKind, find_attr};
 use rustc_errors::MultiSpan;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::intravisit::{self, Visitor, VisitorExt};
 use rustc_hir::{Body, HirId, Item, ItemKind, Node, Path, TyKind};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::{declare_lint, impl_lint_pass};
 use rustc_span::def_id::{DefId, LOCAL_CRATE};
-use rustc_span::{ExpnKind, MacroKind, Span, kw, sym};
+use rustc_span::{ExpnKind, MacroKind, Span, kw};
 
 use crate::lints::{NonLocalDefinitionsCargoUpdateNote, NonLocalDefinitionsDiag};
 use crate::{LateContext, LateLintPass, LintContext, fluent_generated as fluent};
@@ -241,7 +242,10 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions {
                 )
             }
             ItemKind::Macro(_, _macro, MacroKind::Bang)
-                if cx.tcx.has_attr(item.owner_id.def_id, sym::macro_export) =>
+                if find_attr!(
+                    cx.tcx.get_all_attrs(item.owner_id.def_id),
+                    AttributeKind::MacroExport { .. }
+                ) =>
             {
                 cx.emit_span_lint(
                     NON_LOCAL_DEFINITIONS,

compiler/rustc_lint_defs/src/builtin.rs

@@ -4187,8 +4187,13 @@ declare_lint! {
     /// You can't have multiple arguments in a `#[macro_export(..)]`, or mention arguments other than `local_inner_macros`.
     ///
     pub INVALID_MACRO_EXPORT_ARGUMENTS,
-    Warn,
+    Deny,
     "\"invalid_parameter\" isn't a valid argument for `#[macro_export]`",
+    @future_incompatible = FutureIncompatibleInfo {
+        reason: FutureIncompatibilityReason::FutureReleaseError,
+        reference: "issue #57571 <https://github.com/rust-lang/rust/issues/57571>",
+        report_in_deps: true,
+    };
 }
 
 declare_lint! {