1 // Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Support for inlining external documentation into the current AST.
13 use std::collections::BTreeMap;
21 use rustc::hir::def::{Def, CtorKind};
22 use rustc::hir::def_id::DefId;
24 use rustc::util::nodemap::FxHashSet;
26 use core::{DocContext, DocAccessLevels};
28 use clean::{self, GetDefId};
32 /// Attempt to inline a definition into this AST.
34 /// This function will fetch the definition specified, and if it is
35 /// from another crate it will attempt to inline the documentation
36 /// from the other crate into this crate.
38 /// This is primarily used for `pub use` statements which are, in general,
39 /// implementation details. Inlining the documentation should help provide a
40 /// better experience when reading the documentation in this use case.
42 /// The returned value is `None` if the definition could not be inlined,
43 /// and `Some` of a vector of items if it was successfully expanded.
44 pub fn try_inline(cx: &DocContext, def: Def, name: ast::Name)
45 -> Option<Vec<clean::Item>> {
46 if def == Def::Err { return None }
47 let did = def.def_id();
48 if did.is_local() { return None }
49 let mut ret = Vec::new();
50 let inner = match def {
52 record_extern_fqn(cx, did, clean::TypeKind::Trait);
53 ret.extend(build_impls(cx, did));
54 clean::TraitItem(build_external_trait(cx, did))
57 record_extern_fqn(cx, did, clean::TypeKind::Function);
58 clean::FunctionItem(build_external_function(cx, did))
61 record_extern_fqn(cx, did, clean::TypeKind::Struct);
62 ret.extend(build_impls(cx, did));
63 clean::StructItem(build_struct(cx, did))
66 record_extern_fqn(cx, did, clean::TypeKind::Union);
67 ret.extend(build_impls(cx, did));
68 clean::UnionItem(build_union(cx, did))
70 Def::TyAlias(did) => {
71 record_extern_fqn(cx, did, clean::TypeKind::Typedef);
72 ret.extend(build_impls(cx, did));
73 clean::TypedefItem(build_type_alias(cx, did), false)
76 record_extern_fqn(cx, did, clean::TypeKind::Enum);
77 ret.extend(build_impls(cx, did));
78 clean::EnumItem(build_enum(cx, did))
80 Def::TyForeign(did) => {
81 record_extern_fqn(cx, did, clean::TypeKind::Foreign);
82 ret.extend(build_impls(cx, did));
83 clean::ForeignTypeItem
85 // Never inline enum variants but leave them shown as re-exports.
86 Def::Variant(..) => return None,
87 // Assume that enum variants and struct types are re-exported next to
88 // their constructors.
89 Def::VariantCtor(..) |
90 Def::StructCtor(..) => return Some(Vec::new()),
92 record_extern_fqn(cx, did, clean::TypeKind::Module);
93 clean::ModuleItem(build_module(cx, did))
95 Def::Static(did, mtbl) => {
96 record_extern_fqn(cx, did, clean::TypeKind::Static);
97 clean::StaticItem(build_static(cx, did, mtbl))
100 record_extern_fqn(cx, did, clean::TypeKind::Const);
101 clean::ConstantItem(build_const(cx, did))
105 cx.renderinfo.borrow_mut().inlined.insert(did);
106 ret.push(clean::Item {
107 source: cx.tcx.def_span(did).clean(cx),
108 name: Some(name.clean(cx)),
109 attrs: load_attrs(cx, did),
111 visibility: Some(clean::Public),
112 stability: cx.tcx.lookup_stability(did).clean(cx),
113 deprecation: cx.tcx.lookup_deprecation(did).clean(cx),
119 pub fn load_attrs(cx: &DocContext, did: DefId) -> clean::Attributes {
120 cx.tcx.get_attrs(did).clean(cx)
123 /// Record an external fully qualified name in the external_paths cache.
125 /// These names are used later on by HTML rendering to generate things like
126 /// source links back to the original item.
127 pub fn record_extern_fqn(cx: &DocContext, did: DefId, kind: clean::TypeKind) {
128 let crate_name = cx.tcx.crate_name(did.krate).to_string();
129 let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
130 // extern blocks have an empty name
131 let s = elem.data.to_string();
138 let fqn = if let clean::TypeKind::Macro = kind {
139 vec![crate_name, relative.last().unwrap()]
141 once(crate_name).chain(relative).collect()
143 cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind));
146 pub fn build_external_trait(cx: &DocContext, did: DefId) -> clean::Trait {
147 let trait_items = cx.tcx.associated_items(did).map(|item| item.clean(cx)).collect();
148 let predicates = cx.tcx.predicates_of(did);
149 let generics = (cx.tcx.generics_of(did), &predicates).clean(cx);
150 let generics = filter_non_trait_generics(did, generics);
151 let (generics, supertrait_bounds) = separate_supertrait_bounds(generics);
152 let is_spotlight = load_attrs(cx, did).has_doc_flag("spotlight");
153 let is_auto = cx.tcx.trait_is_auto(did);
155 unsafety: cx.tcx.trait_def(did).unsafety,
158 bounds: supertrait_bounds,
164 fn build_external_function(cx: &DocContext, did: DefId) -> clean::Function {
165 let sig = cx.tcx.fn_sig(did);
167 let constness = if cx.tcx.is_const_fn(did) {
168 hir::Constness::Const
170 hir::Constness::NotConst
173 let predicates = cx.tcx.predicates_of(did);
175 decl: (did, sig).clean(cx),
176 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
177 unsafety: sig.unsafety(),
183 fn build_enum(cx: &DocContext, did: DefId) -> clean::Enum {
184 let predicates = cx.tcx.predicates_of(did);
187 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
188 variants_stripped: false,
189 variants: cx.tcx.adt_def(did).variants.clean(cx),
193 fn build_struct(cx: &DocContext, did: DefId) -> clean::Struct {
194 let predicates = cx.tcx.predicates_of(did);
195 let variant = cx.tcx.adt_def(did).non_enum_variant();
198 struct_type: match variant.ctor_kind {
199 CtorKind::Fictive => doctree::Plain,
200 CtorKind::Fn => doctree::Tuple,
201 CtorKind::Const => doctree::Unit,
203 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
204 fields: variant.fields.clean(cx),
205 fields_stripped: false,
209 fn build_union(cx: &DocContext, did: DefId) -> clean::Union {
210 let predicates = cx.tcx.predicates_of(did);
211 let variant = cx.tcx.adt_def(did).non_enum_variant();
214 struct_type: doctree::Plain,
215 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
216 fields: variant.fields.clean(cx),
217 fields_stripped: false,
221 fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
222 let predicates = cx.tcx.predicates_of(did);
225 type_: cx.tcx.type_of(did).clean(cx),
226 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
230 pub fn build_impls(cx: &DocContext, did: DefId) -> Vec<clean::Item> {
232 let mut impls = Vec::new();
234 for &did in tcx.inherent_impls(did).iter() {
235 build_impl(cx, did, &mut impls);
238 // If this is the first time we've inlined something from another crate, then
239 // we inline *all* impls from all the crates into this crate. Note that there's
240 // currently no way for us to filter this based on type, and we likely need
241 // many impls for a variety of reasons.
243 // Primarily, the impls will be used to populate the documentation for this
244 // type being inlined, but impls can also be used when generating
245 // documentation for primitives (no way to find those specifically).
246 if cx.populated_all_crate_impls.get() {
250 cx.populated_all_crate_impls.set(true);
252 for &cnum in tcx.crates().iter() {
253 for did in tcx.all_trait_implementations(cnum).iter() {
254 build_impl(cx, *did, &mut impls);
258 // Also try to inline primitive impls from other crates.
259 let lang_items = tcx.lang_items();
260 let primitive_impls = [
261 lang_items.isize_impl(),
262 lang_items.i8_impl(),
263 lang_items.i16_impl(),
264 lang_items.i32_impl(),
265 lang_items.i64_impl(),
266 lang_items.i128_impl(),
267 lang_items.usize_impl(),
268 lang_items.u8_impl(),
269 lang_items.u16_impl(),
270 lang_items.u32_impl(),
271 lang_items.u64_impl(),
272 lang_items.u128_impl(),
273 lang_items.f32_impl(),
274 lang_items.f64_impl(),
275 lang_items.char_impl(),
276 lang_items.str_impl(),
277 lang_items.slice_impl(),
278 lang_items.slice_u8_impl(),
279 lang_items.const_ptr_impl(),
280 lang_items.mut_ptr_impl(),
283 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
284 if !def_id.is_local() {
285 build_impl(cx, def_id, &mut impls);
292 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
293 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
297 let attrs = load_attrs(cx, did);
299 let associated_trait = tcx.impl_trait_ref(did);
301 // Only inline impl if the implemented trait is
302 // reachable in rustdoc generated documentation
303 if let Some(traitref) = associated_trait {
304 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
309 let for_ = tcx.type_of(did).clean(cx);
311 // Only inline impl if the implementing type is
312 // reachable in rustdoc generated documentation
313 if let Some(did) = for_.def_id() {
314 if !cx.access_levels.borrow().is_doc_reachable(did) {
319 let predicates = tcx.predicates_of(did);
320 let trait_items = tcx.associated_items(did).filter_map(|item| {
321 if associated_trait.is_some() || item.vis == ty::Visibility::Public {
326 }).collect::<Vec<_>>();
327 let polarity = tcx.impl_polarity(did);
328 let trait_ = associated_trait.clean(cx).map(|bound| {
330 clean::TraitBound(polyt, _) => polyt.trait_,
331 clean::RegionBound(..) => unreachable!(),
334 if trait_.def_id() == tcx.lang_items().deref_trait() {
335 super::build_deref_target_impls(cx, &trait_items, ret);
337 if let Some(trait_did) = trait_.def_id() {
338 record_extern_trait(cx, trait_did);
341 let provided = trait_.def_id().map(|did| {
342 tcx.provided_trait_methods(did)
344 .map(|meth| meth.name.to_string())
346 }).unwrap_or(FxHashSet());
348 ret.push(clean::Item {
349 inner: clean::ImplItem(clean::Impl {
350 unsafety: hir::Unsafety::Normal, // FIXME: this should be decoded
351 provided_trait_methods: provided,
354 generics: (tcx.generics_of(did), &predicates).clean(cx),
356 polarity: Some(polarity.clean(cx)),
358 source: tcx.def_span(did).clean(cx),
361 visibility: Some(clean::Inherited),
362 stability: tcx.lookup_stability(did).clean(cx),
363 deprecation: tcx.lookup_deprecation(did).clean(cx),
368 fn build_module(cx: &DocContext, did: DefId) -> clean::Module {
369 let mut items = Vec::new();
370 fill_in(cx, did, &mut items);
371 return clean::Module {
376 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>) {
377 // If we're re-exporting a re-export it may actually re-export something in
378 // two namespaces, so the target may be listed twice. Make sure we only
379 // visit each node at most once.
380 let mut visited = FxHashSet();
381 for &item in cx.tcx.item_children(did).iter() {
382 let def_id = item.def.def_id();
383 if item.vis == ty::Visibility::Public {
384 if !visited.insert(def_id) { continue }
385 if let Some(i) = try_inline(cx, item.def, item.ident.name) {
393 struct InlinedConst {
394 nested_bodies: Rc<BTreeMap<hir::BodyId, hir::Body>>
397 impl hir::print::PpAnn for InlinedConst {
398 fn nested(&self, state: &mut hir::print::State, nested: hir::print::Nested)
400 if let hir::print::Nested::Body(body) = nested {
401 state.print_expr(&self.nested_bodies[&body].value)
408 pub fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
409 let body = cx.tcx.extern_const_body(did).body;
410 let inlined = InlinedConst {
411 nested_bodies: cx.tcx.item_body_nested_bodies(did).nested_bodies
413 hir::print::to_string(&inlined, |s| s.print_expr(&body.value))
416 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
418 type_: cx.tcx.type_of(did).clean(cx),
419 expr: print_inlined_const(cx, did)
423 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
425 type_: cx.tcx.type_of(did).clean(cx),
426 mutability: if mutable {clean::Mutable} else {clean::Immutable},
427 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
431 /// A trait's generics clause actually contains all of the predicates for all of
432 /// its associated types as well. We specifically move these clauses to the
433 /// associated types instead when displaying, so when we're generating the
434 /// generics for the trait itself we need to be sure to remove them.
435 /// We also need to remove the implied "recursive" Self: Trait bound.
437 /// The inverse of this filtering logic can be found in the `Clean`
438 /// implementation for `AssociatedType`
439 fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) -> clean::Generics {
440 for pred in &mut g.where_predicates {
442 clean::WherePredicate::BoundPredicate {
443 ty: clean::Generic(ref s),
445 } if *s == "Self" => {
446 bounds.retain(|bound| {
448 clean::TyParamBound::TraitBound(clean::PolyTrait {
449 trait_: clean::ResolvedPath { did, .. },
451 }, _) => did != trait_did,
460 g.where_predicates.retain(|pred| {
462 clean::WherePredicate::BoundPredicate {
464 self_type: box clean::Generic(ref s),
465 trait_: box clean::ResolvedPath { did, .. },
468 } => !(*s == "Self" && did == trait_did) && !bounds.is_empty(),
475 /// Supertrait bounds for a trait are also listed in the generics coming from
476 /// the metadata for a crate, so we want to separate those out and create a new
477 /// list of explicit supertrait bounds to render nicely.
478 fn separate_supertrait_bounds(mut g: clean::Generics)
479 -> (clean::Generics, Vec<clean::TyParamBound>) {
480 let mut ty_bounds = Vec::new();
481 g.where_predicates.retain(|pred| {
483 clean::WherePredicate::BoundPredicate {
484 ty: clean::Generic(ref s),
486 } if *s == "Self" => {
487 ty_bounds.extend(bounds.iter().cloned());
496 pub fn record_extern_trait(cx: &DocContext, did: DefId) {
497 if cx.external_traits.borrow().contains_key(&did) &&
498 cx.active_extern_traits.borrow().contains(&did)
503 cx.active_extern_traits.borrow_mut().push(did);
505 let trait_ = build_external_trait(cx, did);
507 cx.external_traits.borrow_mut().insert(did, trait_);
508 cx.active_extern_traits.borrow_mut().remove_item(&did);