cfg taken out of Attributes, put in Item

check item.is_fake() instead of self_id.is_some()

Remove empty branching in Attributes::from_ast

diverse small refacto after Josha review

cfg computation moved in merge_attrs

refacto use from_ast twice for coherence

take cfg out of Attributes and move it to Item

Author: Timothée Delabrouille

src/librustdoc/clean/auto_trait.rs

@@ -126,6 +126,7 @@ impl<'a, 'tcx> AutoTraitFinder<'a, 'tcx> {
                 synthetic: true,
                 blanket_impl: None,
             }),
+            cfg: None,
         })
     }
 

src/librustdoc/clean/blanket_impl.rs

@@ -128,6 +128,7 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                         synthetic: false,
                         blanket_impl: Some(trait_ref.self_ty().clean(self.cx)),
                     }),
+                    cfg: None,
                 });
             }
         }

src/librustdoc/clean/inline.rs

@@ -1,6 +1,7 @@
 //! Support for inlining external documentation into the current AST.
 
 use std::iter::once;
+use std::sync::Arc;
 
 use rustc_ast as ast;
 use rustc_data_structures::fx::FxHashSet;
@@ -15,7 +16,7 @@ use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 
-use crate::clean::{self, Attributes, GetDefId, ToSource};
+use crate::clean::{self, Attributes, AttributesExt, GetDefId, ToSource};
 use crate::core::DocContext;
 use crate::formats::item_type::ItemType;
 
@@ -120,11 +121,16 @@ crate fn try_inline(
         _ => return None,
     };
 
-    let target_attrs = load_attrs(cx, did);
-    let attrs = box merge_attrs(cx, Some(parent_module), target_attrs, attrs_clone);
-
+    let (attrs, cfg) = merge_attrs(cx, Some(parent_module), load_attrs(cx, did), attrs_clone);
     cx.inlined.insert(did);
-    ret.push(clean::Item::from_def_id_and_attrs_and_parts(did, Some(name), kind, attrs, cx));
+    ret.push(clean::Item::from_def_id_and_attrs_and_parts(
+        did,
+        Some(name),
+        kind,
+        box attrs,
+        cx,
+        cfg,
+    ));
     Some(ret)
 }
 
@@ -288,22 +294,24 @@ fn merge_attrs(
     parent_module: Option<DefId>,
     old_attrs: Attrs<'_>,
     new_attrs: Option<Attrs<'_>>,
-) -> clean::Attributes {
+) -> (clean::Attributes, Option<Arc<clean::cfg::Cfg>>) {
     // NOTE: If we have additional attributes (from a re-export),
     // always insert them first. This ensure that re-export
     // doc comments show up before the original doc comments
     // when we render them.
     if let Some(inner) = new_attrs {
-        if let Some(new_id) = parent_module {
-            let diag = cx.sess().diagnostic();
-            Attributes::from_ast(diag, old_attrs, Some((inner, new_id)))
-        } else {
-            let mut both = inner.to_vec();
-            both.extend_from_slice(old_attrs);
-            both.clean(cx)
-        }
+        let mut both = inner.to_vec();
+        both.extend_from_slice(old_attrs);
+        (
+            if let Some(new_id) = parent_module {
+                Attributes::from_ast(old_attrs, Some((inner, new_id)))
+            } else {
+                Attributes::from_ast(&both, None)
+            },
+            both.cfg(cx.sess().diagnostic()),
+        )
     } else {
-        old_attrs.clean(cx)
+        (old_attrs.clean(cx), old_attrs.cfg(cx.sess().diagnostic()))
     }
 }
 
@@ -414,8 +422,8 @@ crate fn build_impl(
 
     debug!("build_impl: impl {:?} for {:?}", trait_.def_id(), for_.def_id());
 
-    let attrs = box merge_attrs(cx, parent_module.into(), load_attrs(cx, did), attrs);
-    debug!("merged_attrs={:?}", attrs);
+    let (merged_attrs, cfg) = merge_attrs(cx, parent_module.into(), load_attrs(cx, did), attrs);
+    debug!("merged_attrs={:?}", merged_attrs);
 
     ret.push(clean::Item::from_def_id_and_attrs_and_parts(
         did,
@@ -432,8 +440,9 @@ crate fn build_impl(
             synthetic: false,
             blanket_impl: None,
         }),
-        attrs,
+        box merged_attrs,
         cx,
+        cfg,
     ));
 }
 
@@ -479,6 +488,7 @@ fn build_module(
                         },
                         true,
                     )),
+                    cfg: None,
                 });
             } else if let Some(i) = try_inline(cx, did, item.res, item.ident.name, None, visited) {
                 items.extend(i)

src/librustdoc/clean/mod.rs

@@ -122,8 +122,8 @@ impl Clean<Item> for doctree::Module<'_> {
 }
 
 impl Clean<Attributes> for [ast::Attribute] {
-    fn clean(&self, cx: &mut DocContext<'_>) -> Attributes {
-        Attributes::from_ast(cx.sess().diagnostic(), self, None)
+    fn clean(&self, _cx: &mut DocContext<'_>) -> Attributes {
+        Attributes::from_ast(self, None)
     }
 }
 
@@ -1998,13 +1998,15 @@ fn clean_extern_crate(
             return items;
         }
     }
+
     // FIXME: using `from_def_id_and_kind` breaks `rustdoc/masked` for some reason
     vec![Item {
         name: Some(name),
         attrs: box attrs.clean(cx),
         def_id: crate_def_id,
         visibility: krate.vis.clean(cx),
         kind: box ExternCrateItem { src: orig_name },
+        cfg: attrs.cfg(cx.sess().diagnostic()),
     }]
 }
 

src/librustdoc/clean/types.rs

@@ -219,11 +219,13 @@ crate struct Item {
     /// E.g., struct vs enum vs function.
     crate kind: Box<ItemKind>,
     crate def_id: DefId,
+
+    crate cfg: Option<Arc<Cfg>>,
 }
 
 // `Item` is used a lot. Make sure it doesn't unintentionally get bigger.
 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(Item, 40);
+rustc_data_structures::static_assert_size!(Item, 48);
 
 impl fmt::Debug for Item {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -235,6 +237,7 @@ impl fmt::Debug for Item {
             .field("kind", &self.kind)
             .field("visibility", &self.visibility)
             .field("def_id", def_id)
+            .field("cfg", &self.cfg)
             .finish()
     }
 }
@@ -262,6 +265,10 @@ impl Item {
         if self.is_fake() { None } else { tcx.lookup_deprecation(self.def_id) }
     }
 
+    crate fn inner_docs(&self, tcx: TyCtxt<'_>) -> bool {
+        if self.is_fake() { false } else { tcx.get_attrs(self.def_id).inner_docs() }
+    }
+
     crate fn span(&self, tcx: TyCtxt<'_>) -> Span {
         let kind = match &*self.kind {
             ItemKind::StrippedItem(k) => k,
@@ -305,12 +312,15 @@ impl Item {
         kind: ItemKind,
         cx: &mut DocContext<'_>,
     ) -> Item {
+        let ast_attrs = cx.tcx.get_attrs(def_id);
+
         Self::from_def_id_and_attrs_and_parts(
             def_id,
             name,
             kind,
-            box cx.tcx.get_attrs(def_id).clean(cx),
+            box ast_attrs.clean(cx),
             cx,
+            ast_attrs.cfg(cx.sess().diagnostic()),
         )
     }
 
@@ -320,6 +330,7 @@ impl Item {
         kind: ItemKind,
         attrs: Box<Attributes>,
         cx: &mut DocContext<'_>,
+        cfg: Option<Arc<Cfg>>,
     ) -> Item {
         debug!("name={:?}, def_id={:?}", name, def_id);
 
@@ -329,6 +340,7 @@ impl Item {
             name,
             attrs,
             visibility: cx.tcx.visibility(def_id).clean(cx),
+            cfg,
         }
     }
 
@@ -668,6 +680,8 @@ crate trait AttributesExt {
     fn inner_docs(&self) -> bool;
 
     fn other_attrs(&self) -> Vec<ast::Attribute>;
+
+    fn cfg(&self, diagnostic: &::rustc_errors::Handler) -> Option<Arc<Cfg>>;
 }
 
 impl AttributesExt for [ast::Attribute] {
@@ -691,6 +705,41 @@ impl AttributesExt for [ast::Attribute] {
     fn other_attrs(&self) -> Vec<ast::Attribute> {
         self.iter().filter(|attr| attr.doc_str().is_none()).cloned().collect()
     }
+
+    fn cfg(&self, diagnostic: &::rustc_errors::Handler) -> Option<Arc<Cfg>> {
+        let mut cfg = Cfg::True;
+
+        for attr in self.iter() {
+            if attr.doc_str().is_none() && attr.has_name(sym::doc) {
+                if let Some(mi) = attr.meta() {
+                    if let Some(cfg_mi) = Attributes::extract_cfg(&mi) {
+                        // Extracted #[doc(cfg(...))]
+                        match Cfg::parse(cfg_mi) {
+                            Ok(new_cfg) => cfg &= new_cfg,
+                            Err(e) => diagnostic.span_err(e.span, e.msg),
+                        }
+                    }
+                }
+            }
+        }
+
+        for attr in self.lists(sym::target_feature) {
+            if attr.has_name(sym::enable) {
+                if let Some(feat) = attr.value_str() {
+                    let meta = attr::mk_name_value_item_str(
+                        Ident::with_dummy_span(sym::target_feature),
+                        feat,
+                        DUMMY_SP,
+                    );
+                    if let Ok(feat_cfg) = Cfg::parse(&meta) {
+                        cfg &= feat_cfg;
+                    }
+                }
+            }
+        }
+
+        if cfg == Cfg::True { None } else { Some(Arc::new(cfg)) }
+    }
 }
 
 crate trait NestedAttributesExt {
@@ -799,7 +848,6 @@ impl<'a> FromIterator<&'a DocFragment> for String {
 crate struct Attributes {
     crate doc_strings: Vec<DocFragment>,
     crate other_attrs: Vec<ast::Attribute>,
-    crate cfg: Option<Arc<Cfg>>,
 }
 
 #[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
@@ -914,12 +962,10 @@ impl Attributes {
     }
 
     crate fn from_ast(
-        diagnostic: &::rustc_errors::Handler,
         attrs: &[ast::Attribute],
         additional_attrs: Option<(&[ast::Attribute], DefId)>,
     ) -> Attributes {
         let mut doc_strings: Vec<DocFragment> = vec![];
-        let mut cfg = Cfg::True;
         let mut doc_line = 0;
 
         fn update_need_backline(doc_strings: &mut Vec<DocFragment>, frag: &DocFragment) {
@@ -967,14 +1013,7 @@ impl Attributes {
             } else {
                 if attr.has_name(sym::doc) {
                     if let Some(mi) = attr.meta() {
-                        if let Some(cfg_mi) = Attributes::extract_cfg(&mi) {
-                            // Extracted #[doc(cfg(...))]
-                            match Cfg::parse(cfg_mi) {
-                                Ok(new_cfg) => cfg &= new_cfg,
-                                Err(e) => diagnostic.span_err(e.span, e.msg),
-                            }
-                        } else if let Some((filename, contents)) = Attributes::extract_include(&mi)
-                        {
+                        if let Some((filename, contents)) = Attributes::extract_include(&mi) {
                             let line = doc_line;
                             doc_line += contents.as_str().lines().count();
                             let frag = DocFragment {
@@ -1004,28 +1043,7 @@ impl Attributes {
             .filter_map(clean_attr)
             .collect();
 
-        // treat #[target_feature(enable = "feat")] attributes as if they were
-        // #[doc(cfg(target_feature = "feat"))] attributes as well
-        for attr in attrs.lists(sym::target_feature) {
-            if attr.has_name(sym::enable) {
-                if let Some(feat) = attr.value_str() {
-                    let meta = attr::mk_name_value_item_str(
-                        Ident::with_dummy_span(sym::target_feature),
-                        feat,
-                        DUMMY_SP,
-                    );
-                    if let Ok(feat_cfg) = Cfg::parse(&meta) {
-                        cfg &= feat_cfg;
-                    }
-                }
-            }
-        }
-
-        Attributes {
-            doc_strings,
-            other_attrs,
-            cfg: if cfg == Cfg::True { None } else { Some(Arc::new(cfg)) },
-        }
+        Attributes { doc_strings, other_attrs }
     }
 
     /// Finds the `doc` attribute as a NameValue and returns the corresponding
@@ -1091,7 +1109,6 @@ impl Attributes {
 impl PartialEq for Attributes {
     fn eq(&self, rhs: &Self) -> bool {
         self.doc_strings == rhs.doc_strings
-            && self.cfg == rhs.cfg
             && self
                 .other_attrs
                 .iter()
@@ -1105,7 +1122,6 @@ impl Eq for Attributes {}
 impl Hash for Attributes {
     fn hash<H: Hasher>(&self, hasher: &mut H) {
         self.doc_strings.hash(hasher);
-        self.cfg.hash(hasher);
         for attr in &self.other_attrs {
             attr.id.hash(hasher);
         }

src/librustdoc/doctest.rs

@@ -1093,9 +1093,9 @@ impl<'a, 'hir, 'tcx> HirCollector<'a, 'hir, 'tcx> {
         nested: F,
     ) {
         let ast_attrs = self.tcx.hir().attrs(hir_id);
+        let mut attrs = Attributes::from_ast(ast_attrs, None);
 
-        let mut attrs = Attributes::from_ast(self.sess.diagnostic(), ast_attrs, None);
-        if let Some(ref cfg) = attrs.cfg {
+        if let Some(ref cfg) = ast_attrs.cfg(self.sess.diagnostic()) {
             if !cfg.matches(&self.sess.parse_sess, Some(&self.sess.features_untracked())) {
                 return;
             }

src/librustdoc/html/render/cache.rs

@@ -9,8 +9,7 @@ use serde::ser::{Serialize, SerializeStruct, Serializer};
 
 use crate::clean;
 use crate::clean::types::{
-    AttributesExt, FnDecl, FnRetTy, GenericBound, Generics, GetDefId, Type, TypeKind,
-    WherePredicate,
+    AttributesExt, FnDecl, FnRetTy, GenericBound, Generics, GetDefId, Type, WherePredicate,
 };
 use crate::formats::cache::Cache;
 use crate::formats::item_type::ItemType;

src/librustdoc/html/render/mod.rs

@@ -608,17 +608,12 @@ fn document_item_info(
 }
 
 fn portability(item: &clean::Item, parent: Option<&clean::Item>) -> Option<String> {
-    let cfg = match (&item.attrs.cfg, parent.and_then(|p| p.attrs.cfg.as_ref())) {
+    let cfg = match (&item.cfg, parent.and_then(|p| p.cfg.as_ref())) {
         (Some(cfg), Some(parent_cfg)) => cfg.simplify_with(parent_cfg),
         (cfg, _) => cfg.as_deref().cloned(),
     };
 
-    debug!(
-        "Portability {:?} - {:?} = {:?}",
-        item.attrs.cfg,
-        parent.and_then(|p| p.attrs.cfg.as_ref()),
-        cfg
-    );
+    debug!("Portability {:?} - {:?} = {:?}", item.cfg, parent.and_then(|p| p.cfg.as_ref()), cfg);
 
     Some(format!("<div class=\"stab portability\">{}</div>", cfg?.render_long_html()))
 }