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_span::symbol::sym;
10 pub const COLLECT_TRAIT_IMPLS: Pass = Pass {
11 name: "collect-trait-impls",
12 run: collect_trait_impls,
13 description: "retrieves trait impls for items in the crate",
16 pub fn collect_trait_impls(krate: Crate, cx: &DocContext<'_>) -> Crate {
17 let mut synth = SyntheticImplCollector::new(cx);
18 let mut krate = synth.fold_crate(krate);
20 let prims: FxHashSet<PrimitiveType> = krate.primitives.iter().map(|p| p.1).collect();
23 let mut coll = ItemCollector::new();
24 krate = coll.fold_crate(krate);
28 let mut new_items = Vec::new();
30 for &cnum in cx.tcx.crates().iter() {
31 for &(did, _) in cx.tcx.all_trait_implementations(cnum).iter() {
32 cx.tcx.sess.time("build_extern_trait_impl", || {
33 inline::build_impl(cx, did, None, &mut new_items);
38 // Also try to inline primitive impls from other crates.
39 for &def_id in PrimitiveType::all_impls(cx.tcx).values().flatten() {
40 if !def_id.is_local() {
41 inline::build_impl(cx, def_id, None, &mut new_items);
43 // FIXME(eddyb) is this `doc(hidden)` check needed?
44 if !cx.tcx.get_attrs(def_id).lists(sym::doc).has_word(sym::hidden) {
45 let self_ty = cx.tcx.type_of(def_id);
46 let impls = get_auto_trait_and_blanket_impls(cx, self_ty, def_id);
47 let mut renderinfo = cx.renderinfo.borrow_mut();
49 new_items.extend(impls.filter(|i| renderinfo.inlined.insert(i.def_id)));
54 let mut cleaner = BadImplStripper { prims, items: crate_items };
56 // scan through included items ahead of time to splice in Deref targets to the "valid" sets
57 for it in &new_items {
58 if let ImplItem(Impl { ref for_, ref trait_, ref items, .. }) = it.inner {
59 if cleaner.keep_item(for_) && trait_.def_id() == cx.tcx.lang_items().deref_trait() {
62 .find_map(|item| match item.inner {
63 TypedefItem(ref t, true) => Some(&t.type_),
66 .expect("Deref impl without Target type");
68 if let Some(prim) = target.primitive_type() {
69 cleaner.prims.insert(prim);
70 } else if let Some(did) = target.def_id() {
71 cleaner.items.insert(did);
77 new_items.retain(|it| {
78 if let ImplItem(Impl { ref for_, ref trait_, ref blanket_impl, .. }) = it.inner {
79 cleaner.keep_item(for_)
80 || trait_.as_ref().map_or(false, |t| cleaner.keep_item(t))
81 || blanket_impl.is_some()
87 // `tcx.crates()` doesn't include the local crate, and `tcx.all_trait_implementations`
88 // doesn't work with it anyway, so pull them from the HIR map instead
89 for &trait_did in cx.tcx.all_traits(LOCAL_CRATE).iter() {
90 for &impl_node in cx.tcx.hir().trait_impls(trait_did) {
91 let impl_did = cx.tcx.hir().local_def_id(impl_node);
92 cx.tcx.sess.time("build_local_trait_impl", || {
93 inline::build_impl(cx, impl_did.to_def_id(), None, &mut new_items);
98 if let Some(ref mut it) = krate.module {
99 if let ModuleItem(Module { ref mut items, .. }) = it.inner {
100 items.extend(synth.impls);
101 items.extend(new_items);
103 panic!("collect-trait-impls can't run");
106 panic!("collect-trait-impls can't run");
112 struct SyntheticImplCollector<'a, 'tcx> {
113 cx: &'a DocContext<'tcx>,
117 impl<'a, 'tcx> SyntheticImplCollector<'a, 'tcx> {
118 fn new(cx: &'a DocContext<'tcx>) -> Self {
119 SyntheticImplCollector { cx, impls: Vec::new() }
123 impl<'a, 'tcx> DocFolder for SyntheticImplCollector<'a, 'tcx> {
124 fn fold_item(&mut self, i: Item) -> Option<Item> {
125 if i.is_struct() || i.is_enum() || i.is_union() {
126 // FIXME(eddyb) is this `doc(hidden)` check needed?
127 if !self.cx.tcx.get_attrs(i.def_id).lists(sym::doc).has_word(sym::hidden) {
128 self.impls.extend(get_auto_trait_and_blanket_impls(
130 self.cx.tcx.type_of(i.def_id),
136 self.fold_item_recur(i)
141 struct ItemCollector {
142 items: FxHashSet<DefId>,
151 impl DocFolder for ItemCollector {
152 fn fold_item(&mut self, i: Item) -> Option<Item> {
153 self.items.insert(i.def_id);
155 self.fold_item_recur(i)
159 struct BadImplStripper {
160 prims: FxHashSet<PrimitiveType>,
161 items: FxHashSet<DefId>,
164 impl BadImplStripper {
165 fn keep_item(&self, ty: &Type) -> bool {
166 if let Generic(_) = ty {
167 // keep impls made on generics
169 } else if let Some(prim) = ty.primitive_type() {
170 self.prims.contains(&prim)
171 } else if let Some(did) = ty.def_id() {
172 self.items.contains(&did)