Move some checks from check_doc_attrs directly into rustc_attr_parsing

compiler/rustc_attr_parsing/messages.ftl

@@ -23,6 +23,9 @@ attr_parsing_doc_alias_malformed =
 attr_parsing_doc_alias_start_end =
     {$attr_str} cannot start or end with ' '
 
+attr_parsing_doc_attr_not_crate_level =
+    `#![doc({$attr_name} = "...")]` isn't allowed as a crate-level attribute
+
 attr_parsing_doc_attribute_not_attribute =
     nonexistent builtin attribute `{$attribute}` used in `#[doc(attribute = "...")]`
     .help = only existing builtin attributes are allowed in core/std

compiler/rustc_attr_parsing/src/attributes/doc.rs

@@ -1,5 +1,6 @@
 use rustc_ast::ast::{AttrStyle, LitKind, MetaItemLit};
 use rustc_feature::template;
+use rustc_hir::Target;
 use rustc_hir::attrs::{
     AttributeKind, CfgEntry, CfgHideShow, CfgInfo, DocAttribute, DocInline, HideOrShow,
 };
@@ -12,8 +13,8 @@ use super::{AcceptMapping, AttributeParser};
 use crate::context::{AcceptContext, FinalizeContext, Stage};
 use crate::parser::{ArgParser, MetaItemOrLitParser, MetaItemParser, OwnedPathParser};
 use crate::session_diagnostics::{
-    DocAliasBadChar, DocAliasEmpty, DocAliasMalformed, DocAliasStartEnd, DocAttributeNotAttribute,
-    DocKeywordNotKeyword,
+    DocAliasBadChar, DocAliasEmpty, DocAliasMalformed, DocAliasStartEnd, DocAttrNotCrateLevel,
+    DocAttributeNotAttribute, DocKeywordNotKeyword,
 };
 
 fn check_keyword<S: Stage>(cx: &mut AcceptContext<'_, '_, S>, keyword: Symbol, span: Span) -> bool {
@@ -43,16 +44,39 @@ fn check_attribute<S: Stage>(
     false
 }
 
-fn parse_keyword_and_attribute<S, F>(
+/// Checks that an attribute is *not* used at the crate level. Returns `true` if valid.
+fn check_attr_not_crate_level<S: Stage>(
+    cx: &mut AcceptContext<'_, '_, S>,
+    span: Span,
+    attr_name: Symbol,
+) -> bool {
+    if cx.shared.target.is_some_and(|target| target == Target::Crate) {
+        cx.emit_err(DocAttrNotCrateLevel { span, attr_name });
+        return false;
+    }
+    true
+}
+
+/// Checks that an attribute is used at the crate level. Returns `true` if valid.
+fn check_attr_crate_level<S: Stage>(cx: &mut AcceptContext<'_, '_, S>, span: Span) -> bool {
+    if cx.shared.target.is_some_and(|target| target != Target::Crate) {
+        cx.emit_lint(
+            rustc_session::lint::builtin::INVALID_DOC_ATTRIBUTES,
+            AttributeLintKind::AttrCrateLevelOnly,
+            span,
+        );
+        return false;
+    }
+    true
+}
+
+fn parse_keyword_and_attribute<S: Stage>(
     cx: &mut AcceptContext<'_, '_, S>,
     path: &OwnedPathParser,
     args: &ArgParser,
     attr_value: &mut Option<(Symbol, Span)>,
-    callback: F,
-) where
-    S: Stage,
-    F: FnOnce(&mut AcceptContext<'_, '_, S>, Symbol, Span) -> bool,
-{
+    attr_name: Symbol,
+) {
     let Some(nv) = args.name_value() else {
         cx.expected_name_value(args.span().unwrap_or(path.span()), path.word_sym());
         return;
@@ -63,16 +87,26 @@ fn parse_keyword_and_attribute<S, F>(
         return;
     };
 
-    if !callback(cx, value, nv.value_span) {
+    let ret = if attr_name == sym::keyword {
+        check_keyword(cx, value, nv.value_span)
+    } else {
+        check_attribute(cx, value, nv.value_span)
+    };
+    if !ret {
         return;
     }
 
+    let span = path.span();
     if attr_value.is_some() {
-        cx.duplicate_key(path.span(), path.word_sym().unwrap());
+        cx.duplicate_key(span, path.word_sym().unwrap());
         return;
     }
 
-    *attr_value = Some((value, path.span()));
+    if !check_attr_not_crate_level(cx, span, attr_name) {
+        return;
+    }
+
+    *attr_value = Some((value, span));
 }
 
 #[derive(Default, Debug)]
@@ -102,6 +136,10 @@ impl DocParser {
                     return;
                 }
 
+                if !check_attr_crate_level(cx, path.span()) {
+                    return;
+                }
+
                 self.attribute.no_crate_inject = Some(path.span())
             }
             Some(sym::attr) => {
@@ -155,6 +193,9 @@ impl DocParser {
             cx.emit_err(DocAliasStartEnd { span, attr_str });
             return;
         }
+        if !check_attr_not_crate_level(cx, span, sym::alias) {
+            return;
+        }
 
         if let Some(first_definition) = self.attribute.aliases.get(&alias).copied() {
             cx.emit_lint(
@@ -366,7 +407,33 @@ impl DocParser {
                 self.attribute.$ident = Some(path.span());
             }};
         }
-        macro_rules! string_arg {
+        macro_rules! no_args_and_not_crate_level {
+            ($ident: ident) => {{
+                if let Err(span) = args.no_args() {
+                    cx.expected_no_args(span);
+                    return;
+                }
+                let span = path.span();
+                if !check_attr_not_crate_level(cx, span, sym::$ident) {
+                    return;
+                }
+                self.attribute.$ident = Some(span);
+            }};
+        }
+        macro_rules! no_args_and_crate_level {
+            ($ident: ident) => {{
+                if let Err(span) = args.no_args() {
+                    cx.expected_no_args(span);
+                    return;
+                }
+                let span = path.span();
+                if !check_attr_crate_level(cx, span) {
+                    return;
+                }
+                self.attribute.$ident = Some(span);
+            }};
+        }
+        macro_rules! string_arg_and_crate_level {
             ($ident: ident) => {{
                 let Some(nv) = args.name_value() else {
                     cx.expected_name_value(args.span().unwrap_or(path.span()), path.word_sym());
@@ -378,6 +445,10 @@ impl DocParser {
                     return;
                 };
 
+                if !check_attr_crate_level(cx, path.span()) {
+                    return;
+                }
+
                 // FIXME: It's errorring when the attribute is passed multiple times on the command
                 // line.
                 // The right fix for this would be to only check this rule if the attribute is
@@ -394,12 +465,14 @@ impl DocParser {
         match path.word_sym() {
             Some(sym::alias) => self.parse_alias(cx, path, args),
             Some(sym::hidden) => no_args!(hidden),
-            Some(sym::html_favicon_url) => string_arg!(html_favicon_url),
-            Some(sym::html_logo_url) => string_arg!(html_logo_url),
-            Some(sym::html_no_source) => no_args!(html_no_source),
-            Some(sym::html_playground_url) => string_arg!(html_playground_url),
-            Some(sym::html_root_url) => string_arg!(html_root_url),
-            Some(sym::issue_tracker_base_url) => string_arg!(issue_tracker_base_url),
+            Some(sym::html_favicon_url) => string_arg_and_crate_level!(html_favicon_url),
+            Some(sym::html_logo_url) => string_arg_and_crate_level!(html_logo_url),
+            Some(sym::html_no_source) => no_args_and_crate_level!(html_no_source),
+            Some(sym::html_playground_url) => string_arg_and_crate_level!(html_playground_url),
+            Some(sym::html_root_url) => string_arg_and_crate_level!(html_root_url),
+            Some(sym::issue_tracker_base_url) => {
+                string_arg_and_crate_level!(issue_tracker_base_url)
+            }
             Some(sym::inline) => self.parse_inline(cx, path, args, DocInline::Inline),
             Some(sym::no_inline) => self.parse_inline(cx, path, args, DocInline::NoInline),
             Some(sym::masked) => no_args!(masked),
@@ -410,18 +483,18 @@ impl DocParser {
                 path,
                 args,
                 &mut self.attribute.keyword,
-                check_keyword,
+                sym::keyword,
             ),
             Some(sym::attribute) => parse_keyword_and_attribute(
                 cx,
                 path,
                 args,
                 &mut self.attribute.attribute,
-                check_attribute,
+                sym::attribute,
             ),
-            Some(sym::fake_variadic) => no_args!(fake_variadic),
-            Some(sym::search_unbox) => no_args!(search_unbox),
-            Some(sym::rust_logo) => no_args!(rust_logo),
+            Some(sym::fake_variadic) => no_args_and_not_crate_level!(fake_variadic),
+            Some(sym::search_unbox) => no_args_and_not_crate_level!(search_unbox),
+            Some(sym::rust_logo) => no_args_and_crate_level!(rust_logo),
             Some(sym::auto_cfg) => self.parse_auto_cfg(cx, path, args),
             Some(sym::test) => {
                 let Some(list) = args.list() else {

compiler/rustc_attr_parsing/src/context.rs

@@ -653,6 +653,7 @@ pub struct SharedContext<'p, 'sess, S: Stage> {
     pub(crate) target_span: Span,
     /// The id ([`NodeId`] if `S` is `Early`, [`HirId`] if `S` is `Late`) of the syntactical component this attribute was applied to
     pub(crate) target_id: S::Id,
+    pub(crate) target: Option<rustc_hir::Target>,
 
     pub(crate) emit_lint: &'p mut dyn FnMut(AttributeLint<S::Id>),
 }

compiler/rustc_attr_parsing/src/interface.rs

@@ -218,6 +218,7 @@ impl<'sess> AttributeParser<'sess, Early> {
                 cx: &mut parser,
                 target_span,
                 target_id: target_node_id,
+                target: None,
                 emit_lint: &mut emit_lint,
             },
             attr_span,
@@ -378,6 +379,7 @@ impl<'sess, S: Stage> AttributeParser<'sess, S> {
                                     cx: self,
                                     target_span,
                                     target_id,
+                                    target: Some(target),
                                     emit_lint: &mut emit_lint,
                                 },
                                 attr_span,
@@ -429,6 +431,7 @@ impl<'sess, S: Stage> AttributeParser<'sess, S> {
                     cx: self,
                     target_span,
                     target_id,
+                    target: Some(target),
                     emit_lint: &mut emit_lint,
                 },
                 all_attrs: &attr_paths,

compiler/rustc_attr_parsing/src/session_diagnostics.rs

@@ -47,6 +47,14 @@ pub(crate) struct DocAliasStartEnd<'a> {
     pub attr_str: &'a str,
 }
 
+#[derive(Diagnostic)]
+#[diag(attr_parsing_doc_attr_not_crate_level)]
+pub(crate) struct DocAttrNotCrateLevel {
+    #[primary_span]
+    pub span: Span,
+    pub attr_name: Symbol,
+}
+
 #[derive(Diagnostic)]
 #[diag(attr_parsing_doc_keyword_not_keyword)]
 #[help]

compiler/rustc_lint/messages.ftl

@@ -40,6 +40,11 @@ lint_atomic_ordering_load = atomic loads cannot have `Release` or `AcqRel` order
 lint_atomic_ordering_store = atomic stores cannot have `Acquire` or `AcqRel` ordering
     .help = consider using ordering modes `Release`, `SeqCst` or `Relaxed`
 
+lint_attr_crate_level =
+    this attribute can only be applied at the crate level
+    .suggestion = to apply to the crate, use an inner attribute
+    .note = read <https://doc.rust-lang.org/nightly/rustdoc/the-doc-attribute.html#at-the-crate-level> for more information
+
 lint_bad_attribute_argument = bad attribute argument
 
 lint_bad_opt_access = {$msg}

compiler/rustc_lint/src/early/diagnostics.rs

@@ -417,5 +417,7 @@ pub fn decorate_attribute_lint(
         }
 
         &AttributeLintKind::DocTestLiteral => lints::DocTestLiteral.decorate_lint(diag),
+
+        &AttributeLintKind::AttrCrateLevelOnly => lints::AttrCrateLevelOnly.decorate_lint(diag),
     }
 }

compiler/rustc_lint/src/lints.rs

@@ -3312,3 +3312,8 @@ pub(crate) struct DocTestUnknown {
 #[derive(LintDiagnostic)]
 #[diag(lint_doc_test_literal)]
 pub(crate) struct DocTestLiteral;
+
+#[derive(LintDiagnostic)]
+#[diag(lint_attr_crate_level)]
+#[note]
+pub(crate) struct AttrCrateLevelOnly;

compiler/rustc_lint_defs/src/lib.rs

@@ -820,6 +820,7 @@ pub enum AttributeLintKind {
         name: Symbol,
     },
     DocTestLiteral,
+    AttrCrateLevelOnly,
 }
 
 pub type RegisteredTools = FxIndexSet<Ident>;

compiler/rustc_passes/messages.ftl

@@ -29,11 +29,6 @@ passes_attr_application_struct_union =
     attribute should be applied to a struct or union
     .label = not a struct or union
 
-passes_attr_crate_level =
-    this attribute can only be applied at the crate level
-    .suggestion = to apply to the crate, use an inner attribute
-    .note = read <https://doc.rust-lang.org/nightly/rustdoc/the-doc-attribute.html#at-the-crate-level> for more information
-
 passes_autodiff_attr =
     `#[autodiff]` should be applied to a function
     .label = not a function
@@ -112,9 +107,6 @@ passes_doc_alias_bad_location =
 passes_doc_alias_not_an_alias =
     `#[doc(alias = "{$attr_str}"]` is the same as the item's name
 
-passes_doc_attr_not_crate_level =
-    `#![doc({$attr_name} = "...")]` isn't allowed as a crate-level attribute
-
 passes_doc_fake_variadic_not_valid =
     `#[doc(fake_variadic)]` must be used on the first of a set of tuple or fn pointer trait impls with varying arity