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 // Never inline enum variants but leave them shown as reexports.
81 Def::Variant(..) => return None,
82 // Assume that enum variants and struct types are reexported next to
83 // their constructors.
84 Def::VariantCtor(..) |
85 Def::StructCtor(..) => return Some(Vec::new()),
87 record_extern_fqn(cx, did, clean::TypeKind::Module);
88 clean::ModuleItem(build_module(cx, did))
90 Def::Static(did, mtbl) => {
91 record_extern_fqn(cx, did, clean::TypeKind::Static);
92 clean::StaticItem(build_static(cx, did, mtbl))
95 record_extern_fqn(cx, did, clean::TypeKind::Const);
96 clean::ConstantItem(build_const(cx, did))
100 cx.renderinfo.borrow_mut().inlined.insert(did);
101 ret.push(clean::Item {
102 source: cx.tcx.def_span(did).clean(cx),
103 name: Some(name.clean(cx)),
104 attrs: load_attrs(cx, did),
106 visibility: Some(clean::Public),
107 stability: cx.tcx.lookup_stability(did).clean(cx),
108 deprecation: cx.tcx.lookup_deprecation(did).clean(cx),
114 pub fn load_attrs(cx: &DocContext, did: DefId) -> clean::Attributes {
115 cx.tcx.get_attrs(did).clean(cx)
118 /// Record an external fully qualified name in the external_paths cache.
120 /// These names are used later on by HTML rendering to generate things like
121 /// source links back to the original item.
122 pub fn record_extern_fqn(cx: &DocContext, did: DefId, kind: clean::TypeKind) {
123 let crate_name = cx.tcx.crate_name(did.krate).to_string();
124 let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
125 // extern blocks have an empty name
126 let s = elem.data.to_string();
133 let fqn = once(crate_name).chain(relative).collect();
134 cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind));
137 pub fn build_external_trait(cx: &DocContext, did: DefId) -> clean::Trait {
138 let trait_items = cx.tcx.associated_items(did).map(|item| item.clean(cx)).collect();
139 let predicates = cx.tcx.predicates_of(did);
140 let generics = (cx.tcx.generics_of(did), &predicates).clean(cx);
141 let generics = filter_non_trait_generics(did, generics);
142 let (generics, supertrait_bounds) = separate_supertrait_bounds(generics);
144 unsafety: cx.tcx.trait_def(did).unsafety,
147 bounds: supertrait_bounds,
151 fn build_external_function(cx: &DocContext, did: DefId) -> clean::Function {
152 let sig = cx.tcx.fn_sig(did);
154 let constness = if cx.tcx.is_const_fn(did) {
155 hir::Constness::Const
157 hir::Constness::NotConst
160 let predicates = cx.tcx.predicates_of(did);
162 decl: (did, sig).clean(cx),
163 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
164 unsafety: sig.unsafety(),
170 fn build_enum(cx: &DocContext, did: DefId) -> clean::Enum {
171 let predicates = cx.tcx.predicates_of(did);
174 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
175 variants_stripped: false,
176 variants: cx.tcx.adt_def(did).variants.clean(cx),
180 fn build_struct(cx: &DocContext, did: DefId) -> clean::Struct {
181 let predicates = cx.tcx.predicates_of(did);
182 let variant = cx.tcx.adt_def(did).struct_variant();
185 struct_type: match variant.ctor_kind {
186 CtorKind::Fictive => doctree::Plain,
187 CtorKind::Fn => doctree::Tuple,
188 CtorKind::Const => doctree::Unit,
190 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
191 fields: variant.fields.clean(cx),
192 fields_stripped: false,
196 fn build_union(cx: &DocContext, did: DefId) -> clean::Union {
197 let predicates = cx.tcx.predicates_of(did);
198 let variant = cx.tcx.adt_def(did).struct_variant();
201 struct_type: doctree::Plain,
202 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
203 fields: variant.fields.clean(cx),
204 fields_stripped: false,
208 fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
209 let predicates = cx.tcx.predicates_of(did);
212 type_: cx.tcx.type_of(did).clean(cx),
213 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
217 pub fn build_impls(cx: &DocContext, did: DefId) -> Vec<clean::Item> {
219 let mut impls = Vec::new();
221 for &did in tcx.inherent_impls(did).iter() {
222 build_impl(cx, did, &mut impls);
225 // If this is the first time we've inlined something from another crate, then
226 // we inline *all* impls from all the crates into this crate. Note that there's
227 // currently no way for us to filter this based on type, and we likely need
228 // many impls for a variety of reasons.
230 // Primarily, the impls will be used to populate the documentation for this
231 // type being inlined, but impls can also be used when generating
232 // documentation for primitives (no way to find those specifically).
233 if cx.populated_all_crate_impls.get() {
237 cx.populated_all_crate_impls.set(true);
239 for cnum in tcx.sess.cstore.crates() {
240 for did in tcx.all_trait_implementations(cnum).iter() {
241 build_impl(cx, *did, &mut impls);
245 // Also try to inline primitive impls from other crates.
246 let primitive_impls = [
247 tcx.lang_items.isize_impl(),
248 tcx.lang_items.i8_impl(),
249 tcx.lang_items.i16_impl(),
250 tcx.lang_items.i32_impl(),
251 tcx.lang_items.i64_impl(),
252 tcx.lang_items.i128_impl(),
253 tcx.lang_items.usize_impl(),
254 tcx.lang_items.u8_impl(),
255 tcx.lang_items.u16_impl(),
256 tcx.lang_items.u32_impl(),
257 tcx.lang_items.u64_impl(),
258 tcx.lang_items.u128_impl(),
259 tcx.lang_items.f32_impl(),
260 tcx.lang_items.f64_impl(),
261 tcx.lang_items.char_impl(),
262 tcx.lang_items.str_impl(),
263 tcx.lang_items.slice_impl(),
264 tcx.lang_items.const_ptr_impl(),
265 tcx.lang_items.mut_ptr_impl(),
268 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
269 if !def_id.is_local() {
270 build_impl(cx, def_id, &mut impls);
277 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
278 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
282 let attrs = load_attrs(cx, did);
284 let associated_trait = tcx.impl_trait_ref(did);
286 // Only inline impl if the implemented trait is
287 // reachable in rustdoc generated documentation
288 if let Some(traitref) = associated_trait {
289 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
294 // If this is a defaulted impl, then bail out early here
295 if tcx.is_default_impl(did) {
296 return ret.push(clean::Item {
297 inner: clean::DefaultImplItem(clean::DefaultImpl {
298 // FIXME: this should be decoded
299 unsafety: hir::Unsafety::Normal,
300 trait_: match associated_trait.as_ref().unwrap().clean(cx) {
301 clean::TraitBound(polyt, _) => polyt.trait_,
302 clean::RegionBound(..) => unreachable!(),
305 source: tcx.def_span(did).clean(cx),
308 visibility: Some(clean::Inherited),
309 stability: tcx.lookup_stability(did).clean(cx),
310 deprecation: tcx.lookup_deprecation(did).clean(cx),
315 let for_ = tcx.type_of(did).clean(cx);
317 // Only inline impl if the implementing type is
318 // reachable in rustdoc generated documentation
319 if let Some(did) = for_.def_id() {
320 if !cx.access_levels.borrow().is_doc_reachable(did) {
325 let predicates = tcx.predicates_of(did);
326 let trait_items = tcx.associated_items(did).filter_map(|item| {
328 ty::AssociatedKind::Const => {
329 let default = if item.defaultness.has_value() {
330 Some(print_inlined_const(cx, item.def_id))
335 name: Some(item.name.clean(cx)),
336 inner: clean::AssociatedConstItem(
337 tcx.type_of(item.def_id).clean(cx),
340 source: tcx.def_span(item.def_id).clean(cx),
341 attrs: clean::Attributes::default(),
343 stability: tcx.lookup_stability(item.def_id).clean(cx),
344 deprecation: tcx.lookup_deprecation(item.def_id).clean(cx),
348 ty::AssociatedKind::Method => {
349 if item.vis != ty::Visibility::Public && associated_trait.is_none() {
352 let mut cleaned = item.clean(cx);
353 cleaned.inner = match cleaned.inner.clone() {
354 clean::TyMethodItem(clean::TyMethod {
355 unsafety, decl, generics, abi
357 let constness = if tcx.is_const_fn(item.def_id) {
358 hir::Constness::Const
360 hir::Constness::NotConst
363 clean::MethodItem(clean::Method {
371 ref r => panic!("not a tymethod: {:?}", r),
375 ty::AssociatedKind::Type => {
376 let typedef = clean::Typedef {
377 type_: tcx.type_of(item.def_id).clean(cx),
378 generics: clean::Generics {
381 where_predicates: vec![]
385 name: Some(item.name.clean(cx)),
386 inner: clean::TypedefItem(typedef, true),
387 source: tcx.def_span(item.def_id).clean(cx),
388 attrs: clean::Attributes::default(),
390 stability: tcx.lookup_stability(item.def_id).clean(cx),
391 deprecation: tcx.lookup_deprecation(item.def_id).clean(cx),
396 }).collect::<Vec<_>>();
397 let polarity = tcx.impl_polarity(did);
398 let trait_ = associated_trait.clean(cx).map(|bound| {
400 clean::TraitBound(polyt, _) => polyt.trait_,
401 clean::RegionBound(..) => unreachable!(),
404 if trait_.def_id() == tcx.lang_items.deref_trait() {
405 super::build_deref_target_impls(cx, &trait_items, ret);
408 let provided = trait_.def_id().map(|did| {
409 tcx.provided_trait_methods(did)
411 .map(|meth| meth.name.to_string())
413 }).unwrap_or(FxHashSet());
415 ret.push(clean::Item {
416 inner: clean::ImplItem(clean::Impl {
417 unsafety: hir::Unsafety::Normal, // FIXME: this should be decoded
418 provided_trait_methods: provided,
421 generics: (tcx.generics_of(did), &predicates).clean(cx),
423 polarity: Some(polarity.clean(cx)),
425 source: tcx.def_span(did).clean(cx),
428 visibility: Some(clean::Inherited),
429 stability: tcx.lookup_stability(did).clean(cx),
430 deprecation: tcx.lookup_deprecation(did).clean(cx),
435 fn build_module(cx: &DocContext, did: DefId) -> clean::Module {
436 let mut items = Vec::new();
437 fill_in(cx, did, &mut items);
438 return clean::Module {
443 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>) {
444 // If we're reexporting a reexport it may actually reexport something in
445 // two namespaces, so the target may be listed twice. Make sure we only
446 // visit each node at most once.
447 let mut visited = FxHashSet();
448 for &item in cx.tcx.item_children(did).iter() {
449 let def_id = item.def.def_id();
450 if cx.tcx.visibility(def_id) == ty::Visibility::Public {
451 if !visited.insert(def_id) { continue }
452 if let Some(i) = try_inline(cx, item.def, item.ident.name) {
460 struct InlinedConst {
461 nested_bodies: Rc<BTreeMap<hir::BodyId, hir::Body>>
464 impl hir::print::PpAnn for InlinedConst {
465 fn nested(&self, state: &mut hir::print::State, nested: hir::print::Nested)
467 if let hir::print::Nested::Body(body) = nested {
468 state.print_expr(&self.nested_bodies[&body].value)
475 fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
476 let body = cx.tcx.sess.cstore.item_body(cx.tcx, did);
477 let inlined = InlinedConst {
478 nested_bodies: cx.tcx.item_body_nested_bodies(did)
480 hir::print::to_string(&inlined, |s| s.print_expr(&body.value))
483 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
485 type_: cx.tcx.type_of(did).clean(cx),
486 expr: print_inlined_const(cx, did)
490 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
492 type_: cx.tcx.type_of(did).clean(cx),
493 mutability: if mutable {clean::Mutable} else {clean::Immutable},
494 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
498 /// A trait's generics clause actually contains all of the predicates for all of
499 /// its associated types as well. We specifically move these clauses to the
500 /// associated types instead when displaying, so when we're generating the
501 /// generics for the trait itself we need to be sure to remove them.
502 /// We also need to remove the implied "recursive" Self: Trait bound.
504 /// The inverse of this filtering logic can be found in the `Clean`
505 /// implementation for `AssociatedType`
506 fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics)
508 for pred in &mut g.where_predicates {
510 clean::WherePredicate::BoundPredicate {
511 ty: clean::Generic(ref s),
513 } if *s == "Self" => {
514 bounds.retain(|bound| {
516 clean::TyParamBound::TraitBound(clean::PolyTrait {
517 trait_: clean::ResolvedPath { did, .. },
519 }, _) => did != trait_did,
528 g.where_predicates.retain(|pred| {
530 clean::WherePredicate::BoundPredicate {
532 self_type: box clean::Generic(ref s),
533 trait_: box clean::ResolvedPath { did, .. },
536 } => !(*s == "Self" && did == trait_did) && !bounds.is_empty(),
543 /// Supertrait bounds for a trait are also listed in the generics coming from
544 /// the metadata for a crate, so we want to separate those out and create a new
545 /// list of explicit supertrait bounds to render nicely.
546 fn separate_supertrait_bounds(mut g: clean::Generics)
547 -> (clean::Generics, Vec<clean::TyParamBound>) {
548 let mut ty_bounds = Vec::new();
549 g.where_predicates.retain(|pred| {
551 clean::WherePredicate::BoundPredicate {
552 ty: clean::Generic(ref s),
554 } if *s == "Self" => {
555 ty_bounds.extend(bounds.iter().cloned());