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;
16 use rustc_data_structures::sync::Lrc;
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, get_auto_traits_with_def_id};
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, false));
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, true));
63 clean::StructItem(build_struct(cx, did))
66 record_extern_fqn(cx, did, clean::TypeKind::Union);
67 ret.extend(build_impls(cx, did, true));
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, false));
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, true));
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, false));
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) {
129 debug!("record_extern_fqn(did={:?}, kind+{:?}): def_id is local, aborting", did, kind);
133 let crate_name = cx.tcx.crate_name(did.krate).to_string();
134 let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
135 // extern blocks have an empty name
136 let s = elem.data.to_string();
143 let fqn = if let clean::TypeKind::Macro = kind {
144 vec![crate_name, relative.last().unwrap()]
146 once(crate_name).chain(relative).collect()
148 cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind));
151 pub fn build_external_trait(cx: &DocContext, did: DefId) -> clean::Trait {
152 let auto_trait = cx.tcx.trait_def(did).has_auto_impl;
153 let trait_items = cx.tcx.associated_items(did).map(|item| item.clean(cx)).collect();
154 let predicates = cx.tcx.predicates_of(did);
155 let generics = (cx.tcx.generics_of(did), &predicates).clean(cx);
156 let generics = filter_non_trait_generics(did, generics);
157 let (generics, supertrait_bounds) = separate_supertrait_bounds(generics);
158 let is_spotlight = load_attrs(cx, did).has_doc_flag("spotlight");
159 let is_auto = cx.tcx.trait_is_auto(did);
162 unsafety: cx.tcx.trait_def(did).unsafety,
165 bounds: supertrait_bounds,
171 fn build_external_function(cx: &DocContext, did: DefId) -> clean::Function {
172 let sig = cx.tcx.fn_sig(did);
174 let constness = if cx.tcx.is_const_fn(did) {
175 hir::Constness::Const
177 hir::Constness::NotConst
180 let predicates = cx.tcx.predicates_of(did);
182 decl: (did, sig).clean(cx),
183 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
184 unsafety: sig.unsafety(),
190 fn build_enum(cx: &DocContext, did: DefId) -> clean::Enum {
191 let predicates = cx.tcx.predicates_of(did);
194 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
195 variants_stripped: false,
196 variants: cx.tcx.adt_def(did).variants.clean(cx),
200 fn build_struct(cx: &DocContext, did: DefId) -> clean::Struct {
201 let predicates = cx.tcx.predicates_of(did);
202 let variant = cx.tcx.adt_def(did).non_enum_variant();
205 struct_type: match variant.ctor_kind {
206 CtorKind::Fictive => doctree::Plain,
207 CtorKind::Fn => doctree::Tuple,
208 CtorKind::Const => doctree::Unit,
210 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
211 fields: variant.fields.clean(cx),
212 fields_stripped: false,
216 fn build_union(cx: &DocContext, did: DefId) -> clean::Union {
217 let predicates = cx.tcx.predicates_of(did);
218 let variant = cx.tcx.adt_def(did).non_enum_variant();
221 struct_type: doctree::Plain,
222 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
223 fields: variant.fields.clean(cx),
224 fields_stripped: false,
228 fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
229 let predicates = cx.tcx.predicates_of(did);
232 type_: cx.tcx.type_of(did).clean(cx),
233 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
237 pub fn build_impls(cx: &DocContext, did: DefId, auto_traits: bool) -> Vec<clean::Item> {
239 let mut impls = Vec::new();
241 for &did in tcx.inherent_impls(did).iter() {
242 build_impl(cx, did, &mut impls);
246 let auto_impls = get_auto_traits_with_def_id(cx, did);
247 let mut renderinfo = cx.renderinfo.borrow_mut();
249 let new_impls: Vec<clean::Item> = auto_impls.into_iter()
250 .filter(|i| renderinfo.inlined.insert(i.def_id)).collect();
252 impls.extend(new_impls);
255 // If this is the first time we've inlined something from another crate, then
256 // we inline *all* impls from all the crates into this crate. Note that there's
257 // currently no way for us to filter this based on type, and we likely need
258 // many impls for a variety of reasons.
260 // Primarily, the impls will be used to populate the documentation for this
261 // type being inlined, but impls can also be used when generating
262 // documentation for primitives (no way to find those specifically).
263 if cx.populated_all_crate_impls.get() {
267 cx.populated_all_crate_impls.set(true);
269 for &cnum in tcx.crates().iter() {
270 for did in tcx.all_trait_implementations(cnum).iter() {
271 build_impl(cx, *did, &mut impls);
275 // Also try to inline primitive impls from other crates.
276 let lang_items = tcx.lang_items();
277 let primitive_impls = [
278 lang_items.isize_impl(),
279 lang_items.i8_impl(),
280 lang_items.i16_impl(),
281 lang_items.i32_impl(),
282 lang_items.i64_impl(),
283 lang_items.i128_impl(),
284 lang_items.usize_impl(),
285 lang_items.u8_impl(),
286 lang_items.u16_impl(),
287 lang_items.u32_impl(),
288 lang_items.u64_impl(),
289 lang_items.u128_impl(),
290 lang_items.f32_impl(),
291 lang_items.f64_impl(),
292 lang_items.char_impl(),
293 lang_items.str_impl(),
294 lang_items.slice_impl(),
295 lang_items.slice_u8_impl(),
296 lang_items.const_ptr_impl(),
297 lang_items.mut_ptr_impl(),
300 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
301 if !def_id.is_local() {
302 build_impl(cx, def_id, &mut impls);
309 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
310 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
314 let attrs = load_attrs(cx, did);
316 let associated_trait = tcx.impl_trait_ref(did);
318 // Only inline impl if the implemented trait is
319 // reachable in rustdoc generated documentation
320 if let Some(traitref) = associated_trait {
321 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
326 let for_ = tcx.type_of(did).clean(cx);
328 // Only inline impl if the implementing type is
329 // reachable in rustdoc generated documentation
330 if let Some(did) = for_.def_id() {
331 if !cx.access_levels.borrow().is_doc_reachable(did) {
336 let predicates = tcx.predicates_of(did);
337 let trait_items = tcx.associated_items(did).filter_map(|item| {
338 if associated_trait.is_some() || item.vis == ty::Visibility::Public {
343 }).collect::<Vec<_>>();
344 let polarity = tcx.impl_polarity(did);
345 let trait_ = associated_trait.clean(cx).map(|bound| {
347 clean::TraitBound(polyt, _) => polyt.trait_,
348 clean::RegionBound(..) => unreachable!(),
351 if trait_.def_id() == tcx.lang_items().deref_trait() {
352 super::build_deref_target_impls(cx, &trait_items, ret);
354 if let Some(trait_did) = trait_.def_id() {
355 record_extern_trait(cx, trait_did);
358 let provided = trait_.def_id().map(|did| {
359 tcx.provided_trait_methods(did)
361 .map(|meth| meth.name.to_string())
363 }).unwrap_or(FxHashSet());
365 ret.push(clean::Item {
366 inner: clean::ImplItem(clean::Impl {
367 unsafety: hir::Unsafety::Normal,
368 generics: (tcx.generics_of(did), &predicates).clean(cx),
369 provided_trait_methods: provided,
373 polarity: Some(polarity.clean(cx)),
376 source: tcx.def_span(did).clean(cx),
379 visibility: Some(clean::Inherited),
380 stability: tcx.lookup_stability(did).clean(cx),
381 deprecation: tcx.lookup_deprecation(did).clean(cx),
386 fn build_module(cx: &DocContext, did: DefId) -> clean::Module {
387 let mut items = Vec::new();
388 fill_in(cx, did, &mut items);
389 return clean::Module {
394 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>) {
395 // If we're re-exporting a re-export it may actually re-export something in
396 // two namespaces, so the target may be listed twice. Make sure we only
397 // visit each node at most once.
398 let mut visited = FxHashSet();
399 for &item in cx.tcx.item_children(did).iter() {
400 let def_id = item.def.def_id();
401 if item.vis == ty::Visibility::Public {
402 if !visited.insert(def_id) { continue }
403 if let Some(i) = try_inline(cx, item.def, item.ident.name) {
411 struct InlinedConst {
412 nested_bodies: Lrc<BTreeMap<hir::BodyId, hir::Body>>
415 impl hir::print::PpAnn for InlinedConst {
416 fn nested(&self, state: &mut hir::print::State, nested: hir::print::Nested)
418 if let hir::print::Nested::Body(body) = nested {
419 state.print_expr(&self.nested_bodies[&body].value)
426 pub fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
427 let body = cx.tcx.extern_const_body(did).body;
428 let inlined = InlinedConst {
429 nested_bodies: cx.tcx.item_body_nested_bodies(did).nested_bodies
431 hir::print::to_string(&inlined, |s| s.print_expr(&body.value))
434 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
436 type_: cx.tcx.type_of(did).clean(cx),
437 expr: print_inlined_const(cx, did)
441 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
443 type_: cx.tcx.type_of(did).clean(cx),
444 mutability: if mutable {clean::Mutable} else {clean::Immutable},
445 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
449 /// A trait's generics clause actually contains all of the predicates for all of
450 /// its associated types as well. We specifically move these clauses to the
451 /// associated types instead when displaying, so when we're generating the
452 /// generics for the trait itself we need to be sure to remove them.
453 /// We also need to remove the implied "recursive" Self: Trait bound.
455 /// The inverse of this filtering logic can be found in the `Clean`
456 /// implementation for `AssociatedType`
457 fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) -> clean::Generics {
458 for pred in &mut g.where_predicates {
460 clean::WherePredicate::BoundPredicate {
461 ty: clean::Generic(ref s),
463 } if *s == "Self" => {
464 bounds.retain(|bound| {
466 clean::TyParamBound::TraitBound(clean::PolyTrait {
467 trait_: clean::ResolvedPath { did, .. },
469 }, _) => did != trait_did,
478 g.where_predicates.retain(|pred| {
480 clean::WherePredicate::BoundPredicate {
482 self_type: box clean::Generic(ref s),
483 trait_: box clean::ResolvedPath { did, .. },
486 } => !(*s == "Self" && did == trait_did) && !bounds.is_empty(),
493 /// Supertrait bounds for a trait are also listed in the generics coming from
494 /// the metadata for a crate, so we want to separate those out and create a new
495 /// list of explicit supertrait bounds to render nicely.
496 fn separate_supertrait_bounds(mut g: clean::Generics)
497 -> (clean::Generics, Vec<clean::TyParamBound>) {
498 let mut ty_bounds = Vec::new();
499 g.where_predicates.retain(|pred| {
501 clean::WherePredicate::BoundPredicate {
502 ty: clean::Generic(ref s),
504 } if *s == "Self" => {
505 ty_bounds.extend(bounds.iter().cloned());
514 pub fn record_extern_trait(cx: &DocContext, did: DefId) {
515 if cx.external_traits.borrow().contains_key(&did) ||
516 cx.active_extern_traits.borrow().contains(&did)
521 cx.active_extern_traits.borrow_mut().push(did);
523 let trait_ = build_external_trait(cx, did);
525 cx.external_traits.borrow_mut().insert(did, trait_);
526 cx.active_extern_traits.borrow_mut().remove_item(&did);