3 use crate::core::DocContext;
4 use crate::fold::DocFolder;
6 use rustc_data_structures::fx::FxHashSet;
7 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
8 use rustc_middle::ty::DefIdTree;
9 use rustc_span::symbol::sym;
11 crate const COLLECT_TRAIT_IMPLS: Pass = Pass {
12 name: "collect-trait-impls",
13 run: collect_trait_impls,
14 description: "retrieves trait impls for items in the crate",
17 crate fn collect_trait_impls(krate: Crate, cx: &DocContext<'_>) -> Crate {
18 let mut synth = SyntheticImplCollector::new(cx);
19 let mut krate = synth.fold_crate(krate);
21 let prims: FxHashSet<PrimitiveType> = krate.primitives.iter().map(|p| p.1).collect();
24 let mut coll = ItemCollector::new();
25 krate = coll.fold_crate(krate);
29 let mut new_items = Vec::new();
31 for &cnum in cx.tcx.crates().iter() {
32 for &(did, _) in cx.tcx.all_trait_implementations(cnum).iter() {
33 cx.tcx.sess.time("build_extern_trait_impl", || {
34 inline::build_impl(cx, None, did, None, &mut new_items);
39 // Also try to inline primitive impls from other crates.
40 for &def_id in PrimitiveType::all_impls(cx.tcx).values().flatten() {
41 if !def_id.is_local() {
42 inline::build_impl(cx, None, def_id, None, &mut new_items);
44 // FIXME(eddyb) is this `doc(hidden)` check needed?
45 if !cx.tcx.get_attrs(def_id).lists(sym::doc).has_word(sym::hidden) {
46 let self_ty = cx.tcx.type_of(def_id);
47 let impls = get_auto_trait_and_blanket_impls(cx, self_ty, def_id);
48 let mut renderinfo = cx.renderinfo.borrow_mut();
50 new_items.extend(impls.filter(|i| renderinfo.inlined.insert(i.def_id)));
55 let mut cleaner = BadImplStripper { prims, items: crate_items };
57 // scan through included items ahead of time to splice in Deref targets to the "valid" sets
58 for it in &new_items {
59 if let ImplItem(Impl { ref for_, ref trait_, ref items, .. }) = it.kind {
60 if cleaner.keep_item(for_) && trait_.def_id() == cx.tcx.lang_items().deref_trait() {
63 .find_map(|item| match item.kind {
64 TypedefItem(ref t, true) => Some(&t.type_),
67 .expect("Deref impl without Target type");
69 if let Some(prim) = target.primitive_type() {
70 cleaner.prims.insert(prim);
71 } else if let Some(did) = target.def_id() {
72 cleaner.items.insert(did);
78 new_items.retain(|it| {
79 if let ImplItem(Impl { ref for_, ref trait_, ref blanket_impl, .. }) = it.kind {
80 cleaner.keep_item(for_)
81 || trait_.as_ref().map_or(false, |t| cleaner.keep_item(t))
82 || blanket_impl.is_some()
88 // `tcx.crates()` doesn't include the local crate, and `tcx.all_trait_implementations`
89 // doesn't work with it anyway, so pull them from the HIR map instead
90 for &trait_did in cx.tcx.all_traits(LOCAL_CRATE).iter() {
91 for &impl_node in cx.tcx.hir().trait_impls(trait_did) {
92 let impl_did = cx.tcx.hir().local_def_id(impl_node);
93 cx.tcx.sess.time("build_local_trait_impl", || {
94 let mut extra_attrs = Vec::new();
95 let mut parent = cx.tcx.parent(impl_did.to_def_id());
96 while let Some(did) = parent {
101 .filter(|attr| attr.has_name(sym::doc))
103 if let Some([attr]) = attr.meta_item_list().as_deref() {
104 attr.has_name(sym::cfg)
111 parent = cx.tcx.parent(did);
116 impl_did.to_def_id(),
124 if let Some(ref mut it) = krate.module {
125 if let ModuleItem(Module { ref mut items, .. }) = it.kind {
126 items.extend(synth.impls);
127 items.extend(new_items);
129 panic!("collect-trait-impls can't run");
132 panic!("collect-trait-impls can't run");
138 struct SyntheticImplCollector<'a, 'tcx> {
139 cx: &'a DocContext<'tcx>,
143 impl<'a, 'tcx> SyntheticImplCollector<'a, 'tcx> {
144 fn new(cx: &'a DocContext<'tcx>) -> Self {
145 SyntheticImplCollector { cx, impls: Vec::new() }
149 impl<'a, 'tcx> DocFolder for SyntheticImplCollector<'a, 'tcx> {
150 fn fold_item(&mut self, i: Item) -> Option<Item> {
151 if i.is_struct() || i.is_enum() || i.is_union() {
152 // FIXME(eddyb) is this `doc(hidden)` check needed?
153 if !self.cx.tcx.get_attrs(i.def_id).lists(sym::doc).has_word(sym::hidden) {
154 self.impls.extend(get_auto_trait_and_blanket_impls(
156 self.cx.tcx.type_of(i.def_id),
162 Some(self.fold_item_recur(i))
167 struct ItemCollector {
168 items: FxHashSet<DefId>,
177 impl DocFolder for ItemCollector {
178 fn fold_item(&mut self, i: Item) -> Option<Item> {
179 self.items.insert(i.def_id);
181 Some(self.fold_item_recur(i))
185 struct BadImplStripper {
186 prims: FxHashSet<PrimitiveType>,
187 items: FxHashSet<DefId>,
190 impl BadImplStripper {
191 fn keep_item(&self, ty: &Type) -> bool {
192 if let Generic(_) = ty {
193 // keep impls made on generics
195 } else if let Some(prim) = ty.primitive_type() {
196 self.prims.contains(&prim)
197 } else if let Some(did) = ty.def_id() {
198 self.items.contains(&did)