| use super::Pass; |
| use crate::clean::*; |
| use crate::core::DocContext; |
| use crate::fold::DocFolder; |
| |
| use rustc_data_structures::fx::{FxHashMap, FxHashSet}; |
| use rustc_hir::def_id::{DefId, LOCAL_CRATE}; |
| use rustc_middle::ty::DefIdTree; |
| use rustc_span::symbol::sym; |
| |
| crate const COLLECT_TRAIT_IMPLS: Pass = Pass { |
| name: "collect-trait-impls", |
| run: collect_trait_impls, |
| description: "retrieves trait impls for items in the crate", |
| }; |
| |
| crate fn collect_trait_impls(krate: Crate, cx: &DocContext<'_>) -> Crate { |
| let mut synth = SyntheticImplCollector::new(cx); |
| let mut krate = cx.sess().time("collect_synthetic_impls", || synth.fold_crate(krate)); |
| |
| let prims: FxHashSet<PrimitiveType> = krate.primitives.iter().map(|p| p.1).collect(); |
| |
| let crate_items = { |
| let mut coll = ItemCollector::new(); |
| krate = cx.sess().time("collect_items_for_trait_impls", || coll.fold_crate(krate)); |
| coll.items |
| }; |
| |
| let mut new_items = Vec::new(); |
| |
| for &cnum in cx.tcx.crates().iter() { |
| for &(did, _) in cx.tcx.all_trait_implementations(cnum).iter() { |
| cx.tcx.sess.time("build_extern_trait_impl", || { |
| inline::build_impl(cx, None, did, None, &mut new_items); |
| }); |
| } |
| } |
| |
| // Also try to inline primitive impls from other crates. |
| for &def_id in PrimitiveType::all_impls(cx.tcx).values().flatten() { |
| if !def_id.is_local() { |
| cx.sess().time("build_primitive_trait_impl", || { |
| inline::build_impl(cx, None, def_id, None, &mut new_items); |
| |
| // FIXME(eddyb) is this `doc(hidden)` check needed? |
| if !cx.tcx.get_attrs(def_id).lists(sym::doc).has_word(sym::hidden) { |
| let self_ty = cx.tcx.type_of(def_id); |
| let impls = get_auto_trait_and_blanket_impls(cx, self_ty, def_id); |
| let mut renderinfo = cx.renderinfo.borrow_mut(); |
| |
| new_items.extend(impls.filter(|i| renderinfo.inlined.insert(i.def_id))); |
| } |
| }) |
| } |
| } |
| |
| // `tcx.crates()` doesn't include the local crate, and `tcx.all_trait_implementations` |
| // doesn't work with it anyway, so pull them from the HIR map instead |
| for &trait_did in cx.tcx.all_traits(LOCAL_CRATE).iter() { |
| for &impl_node in cx.tcx.hir().trait_impls(trait_did) { |
| let impl_did = cx.tcx.hir().local_def_id(impl_node); |
| cx.tcx.sess.time("build_local_trait_impl", || { |
| let mut extra_attrs = Vec::new(); |
| let mut parent = cx.tcx.parent(impl_did.to_def_id()); |
| while let Some(did) = parent { |
| extra_attrs.extend( |
| cx.tcx |
| .get_attrs(did) |
| .iter() |
| .filter(|attr| attr.has_name(sym::doc)) |
| .filter(|attr| { |
| if let Some([attr]) = attr.meta_item_list().as_deref() { |
| attr.has_name(sym::cfg) |
| } else { |
| false |
| } |
| }) |
| .cloned(), |
| ); |
| parent = cx.tcx.parent(did); |
| } |
| inline::build_impl( |
| cx, |
| None, |
| impl_did.to_def_id(), |
| Some(&extra_attrs), |
| &mut new_items, |
| ); |
| }); |
| } |
| } |
| |
| let mut cleaner = BadImplStripper { prims, items: crate_items }; |
| |
| let mut type_did_to_deref_target: FxHashMap<DefId, &Type> = FxHashMap::default(); |
| // Gather all type to `Deref` target edges. |
| for it in &new_items { |
| if let ImplItem(Impl { ref for_, ref trait_, ref items, .. }) = *it.kind { |
| if trait_.def_id() == cx.tcx.lang_items().deref_trait() { |
| let target = items.iter().find_map(|item| match *item.kind { |
| TypedefItem(ref t, true) => Some(&t.type_), |
| _ => None, |
| }); |
| if let (Some(for_did), Some(target)) = (for_.def_id(), target) { |
| type_did_to_deref_target.insert(for_did, target); |
| } |
| } |
| } |
| } |
| // Follow all `Deref` targets of included items and recursively add them as valid |
| fn add_deref_target( |
| map: &FxHashMap<DefId, &Type>, |
| cleaner: &mut BadImplStripper, |
| type_did: &DefId, |
| ) { |
| if let Some(target) = map.get(type_did) { |
| debug!("add_deref_target: type {:?}, target {:?}", type_did, target); |
| if let Some(target_prim) = target.primitive_type() { |
| cleaner.prims.insert(target_prim); |
| } else if let Some(target_did) = target.def_id() { |
| // `impl Deref<Target = S> for S` |
| if target_did == *type_did { |
| // Avoid infinite cycles |
| return; |
| } |
| cleaner.items.insert(target_did); |
| add_deref_target(map, cleaner, &target_did); |
| } |
| } |
| } |
| for type_did in type_did_to_deref_target.keys() { |
| // Since only the `DefId` portion of the `Type` instances is known to be same for both the |
| // `Deref` target type and the impl for type positions, this map of types is keyed by |
| // `DefId` and for convenience uses a special cleaner that accepts `DefId`s directly. |
| if cleaner.keep_impl_with_def_id(type_did) { |
| add_deref_target(&type_did_to_deref_target, &mut cleaner, type_did); |
| } |
| } |
| |
| new_items.retain(|it| { |
| if let ImplItem(Impl { ref for_, ref trait_, ref blanket_impl, .. }) = *it.kind { |
| cleaner.keep_impl(for_) |
| || trait_.as_ref().map_or(false, |t| cleaner.keep_impl(t)) |
| || blanket_impl.is_some() |
| } else { |
| true |
| } |
| }); |
| |
| if let Some(ref mut it) = krate.module { |
| if let ModuleItem(Module { ref mut items, .. }) = *it.kind { |
| items.extend(synth.impls); |
| items.extend(new_items); |
| } else { |
| panic!("collect-trait-impls can't run"); |
| } |
| } else { |
| panic!("collect-trait-impls can't run"); |
| } |
| |
| krate |
| } |
| |
| struct SyntheticImplCollector<'a, 'tcx> { |
| cx: &'a DocContext<'tcx>, |
| impls: Vec<Item>, |
| } |
| |
| impl<'a, 'tcx> SyntheticImplCollector<'a, 'tcx> { |
| fn new(cx: &'a DocContext<'tcx>) -> Self { |
| SyntheticImplCollector { cx, impls: Vec::new() } |
| } |
| } |
| |
| impl<'a, 'tcx> DocFolder for SyntheticImplCollector<'a, 'tcx> { |
| fn fold_item(&mut self, i: Item) -> Option<Item> { |
| if i.is_struct() || i.is_enum() || i.is_union() { |
| // FIXME(eddyb) is this `doc(hidden)` check needed? |
| if !self.cx.tcx.get_attrs(i.def_id).lists(sym::doc).has_word(sym::hidden) { |
| self.cx.sess().time("get_auto_trait_and_blanket_synthetic_impls", || { |
| self.impls.extend(get_auto_trait_and_blanket_impls( |
| self.cx, |
| self.cx.tcx.type_of(i.def_id), |
| i.def_id, |
| )); |
| }); |
| } |
| } |
| |
| Some(self.fold_item_recur(i)) |
| } |
| } |
| |
| #[derive(Default)] |
| struct ItemCollector { |
| items: FxHashSet<DefId>, |
| } |
| |
| impl ItemCollector { |
| fn new() -> Self { |
| Self::default() |
| } |
| } |
| |
| impl DocFolder for ItemCollector { |
| fn fold_item(&mut self, i: Item) -> Option<Item> { |
| self.items.insert(i.def_id); |
| |
| Some(self.fold_item_recur(i)) |
| } |
| } |
| |
| struct BadImplStripper { |
| prims: FxHashSet<PrimitiveType>, |
| items: FxHashSet<DefId>, |
| } |
| |
| impl BadImplStripper { |
| fn keep_impl(&self, ty: &Type) -> bool { |
| if let Generic(_) = ty { |
| // keep impls made on generics |
| true |
| } else if let Some(prim) = ty.primitive_type() { |
| self.prims.contains(&prim) |
| } else if let Some(did) = ty.def_id() { |
| self.keep_impl_with_def_id(&did) |
| } else { |
| false |
| } |
| } |
| |
| fn keep_impl_with_def_id(&self, did: &DefId) -> bool { |
| self.items.contains(did) |
| } |
| } |