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 // Assume that the enum type is reexported next to the variant, and
81 // variants don't show up in documentation specially.
82 // Similarly, consider that struct type is reexported next to its constructor.
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.sess.cstore.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.type_of(did).fn_sig();
154 let constness = if cx.tcx.sess.cstore.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(),
165 constness: constness,
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 did in tcx.sess.cstore.implementations_of_trait(None) {
240 build_impl(cx, did, &mut impls);
243 // Also try to inline primitive impls from other crates.
244 let primitive_impls = [
245 tcx.lang_items.isize_impl(),
246 tcx.lang_items.i8_impl(),
247 tcx.lang_items.i16_impl(),
248 tcx.lang_items.i32_impl(),
249 tcx.lang_items.i64_impl(),
250 tcx.lang_items.i128_impl(),
251 tcx.lang_items.usize_impl(),
252 tcx.lang_items.u8_impl(),
253 tcx.lang_items.u16_impl(),
254 tcx.lang_items.u32_impl(),
255 tcx.lang_items.u64_impl(),
256 tcx.lang_items.u128_impl(),
257 tcx.lang_items.f32_impl(),
258 tcx.lang_items.f64_impl(),
259 tcx.lang_items.char_impl(),
260 tcx.lang_items.str_impl(),
261 tcx.lang_items.slice_impl(),
262 tcx.lang_items.const_ptr_impl(),
263 tcx.lang_items.mut_ptr_impl(),
266 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
267 if !def_id.is_local() {
268 build_impl(cx, def_id, &mut impls);
275 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
276 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
280 let attrs = load_attrs(cx, did);
282 let associated_trait = tcx.impl_trait_ref(did);
284 // Only inline impl if the implemented trait is
285 // reachable in rustdoc generated documentation
286 if let Some(traitref) = associated_trait {
287 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
292 // If this is a defaulted impl, then bail out early here
293 if tcx.sess.cstore.is_default_impl(did) {
294 return ret.push(clean::Item {
295 inner: clean::DefaultImplItem(clean::DefaultImpl {
296 // FIXME: this should be decoded
297 unsafety: hir::Unsafety::Normal,
298 trait_: match associated_trait.as_ref().unwrap().clean(cx) {
299 clean::TraitBound(polyt, _) => polyt.trait_,
300 clean::RegionBound(..) => unreachable!(),
303 source: tcx.def_span(did).clean(cx),
306 visibility: Some(clean::Inherited),
307 stability: tcx.lookup_stability(did).clean(cx),
308 deprecation: tcx.lookup_deprecation(did).clean(cx),
313 let for_ = tcx.type_of(did).clean(cx);
315 // Only inline impl if the implementing type is
316 // reachable in rustdoc generated documentation
317 if let Some(did) = for_.def_id() {
318 if !cx.access_levels.borrow().is_doc_reachable(did) {
323 let predicates = tcx.predicates_of(did);
324 let trait_items = tcx.associated_items(did).filter_map(|item| {
326 ty::AssociatedKind::Const => {
327 let default = if item.defaultness.has_value() {
328 Some(print_inlined_const(cx, item.def_id))
333 name: Some(item.name.clean(cx)),
334 inner: clean::AssociatedConstItem(
335 tcx.type_of(item.def_id).clean(cx),
338 source: tcx.def_span(item.def_id).clean(cx),
339 attrs: clean::Attributes::default(),
341 stability: tcx.lookup_stability(item.def_id).clean(cx),
342 deprecation: tcx.lookup_deprecation(item.def_id).clean(cx),
346 ty::AssociatedKind::Method => {
347 if item.vis != ty::Visibility::Public && associated_trait.is_none() {
350 let mut cleaned = item.clean(cx);
351 cleaned.inner = match cleaned.inner.clone() {
352 clean::TyMethodItem(clean::TyMethod {
353 unsafety, decl, generics, abi
355 let constness = if tcx.sess.cstore.is_const_fn(item.def_id) {
356 hir::Constness::Const
358 hir::Constness::NotConst
361 clean::MethodItem(clean::Method {
363 constness: constness,
369 ref r => panic!("not a tymethod: {:?}", r),
373 ty::AssociatedKind::Type => {
374 let typedef = clean::Typedef {
375 type_: tcx.type_of(item.def_id).clean(cx),
376 generics: clean::Generics {
379 where_predicates: vec![]
383 name: Some(item.name.clean(cx)),
384 inner: clean::TypedefItem(typedef, true),
385 source: tcx.def_span(item.def_id).clean(cx),
386 attrs: clean::Attributes::default(),
388 stability: tcx.lookup_stability(item.def_id).clean(cx),
389 deprecation: tcx.lookup_deprecation(item.def_id).clean(cx),
394 }).collect::<Vec<_>>();
395 let polarity = tcx.impl_polarity(did);
396 let trait_ = associated_trait.clean(cx).map(|bound| {
398 clean::TraitBound(polyt, _) => polyt.trait_,
399 clean::RegionBound(..) => unreachable!(),
402 if trait_.def_id() == tcx.lang_items.deref_trait() {
403 super::build_deref_target_impls(cx, &trait_items, ret);
406 let provided = trait_.def_id().map(|did| {
407 tcx.provided_trait_methods(did)
409 .map(|meth| meth.name.to_string())
411 }).unwrap_or(FxHashSet());
413 ret.push(clean::Item {
414 inner: clean::ImplItem(clean::Impl {
415 unsafety: hir::Unsafety::Normal, // FIXME: this should be decoded
416 provided_trait_methods: provided,
419 generics: (tcx.generics_of(did), &predicates).clean(cx),
421 polarity: Some(polarity.clean(cx)),
423 source: tcx.def_span(did).clean(cx),
426 visibility: Some(clean::Inherited),
427 stability: tcx.lookup_stability(did).clean(cx),
428 deprecation: tcx.lookup_deprecation(did).clean(cx),
433 fn build_module(cx: &DocContext, did: DefId) -> clean::Module {
434 let mut items = Vec::new();
435 fill_in(cx, did, &mut items);
436 return clean::Module {
441 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>) {
442 // If we're reexporting a reexport it may actually reexport something in
443 // two namespaces, so the target may be listed twice. Make sure we only
444 // visit each node at most once.
445 let mut visited = FxHashSet();
446 for item in cx.tcx.sess.cstore.item_children(did) {
447 let def_id = item.def.def_id();
448 if cx.tcx.sess.cstore.visibility(def_id) == ty::Visibility::Public {
449 if !visited.insert(def_id) { continue }
450 if let Some(i) = try_inline(cx, item.def, item.name) {
458 struct InlinedConst {
459 nested_bodies: Rc<BTreeMap<hir::BodyId, hir::Body>>
462 impl hir::print::PpAnn for InlinedConst {
463 fn nested(&self, state: &mut hir::print::State, nested: hir::print::Nested)
465 if let hir::print::Nested::Body(body) = nested {
466 state.print_expr(&self.nested_bodies[&body].value)
473 fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
474 let body = cx.tcx.sess.cstore.item_body(cx.tcx, did);
475 let inlined = InlinedConst {
476 nested_bodies: cx.tcx.item_body_nested_bodies(did)
478 hir::print::to_string(&inlined, |s| s.print_expr(&body.value))
481 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
483 type_: cx.tcx.type_of(did).clean(cx),
484 expr: print_inlined_const(cx, did)
488 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
490 type_: cx.tcx.type_of(did).clean(cx),
491 mutability: if mutable {clean::Mutable} else {clean::Immutable},
492 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
496 /// A trait's generics clause actually contains all of the predicates for all of
497 /// its associated types as well. We specifically move these clauses to the
498 /// associated types instead when displaying, so when we're genering the
499 /// generics for the trait itself we need to be sure to remove them.
500 /// We also need to remove the implied "recursive" Self: Trait bound.
502 /// The inverse of this filtering logic can be found in the `Clean`
503 /// implementation for `AssociatedType`
504 fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics)
506 for pred in &mut g.where_predicates {
508 clean::WherePredicate::BoundPredicate {
509 ty: clean::Generic(ref s),
511 } if *s == "Self" => {
512 bounds.retain(|bound| {
514 clean::TyParamBound::TraitBound(clean::PolyTrait {
515 trait_: clean::ResolvedPath { did, .. },
517 }, _) => did != trait_did,
526 g.where_predicates.retain(|pred| {
528 clean::WherePredicate::BoundPredicate {
530 self_type: box clean::Generic(ref s),
531 trait_: box clean::ResolvedPath { did, .. },
534 } => !(*s == "Self" && did == trait_did) && !bounds.is_empty(),
541 /// Supertrait bounds for a trait are also listed in the generics coming from
542 /// the metadata for a crate, so we want to separate those out and create a new
543 /// list of explicit supertrait bounds to render nicely.
544 fn separate_supertrait_bounds(mut g: clean::Generics)
545 -> (clean::Generics, Vec<clean::TyParamBound>) {
546 let mut ty_bounds = Vec::new();
547 g.where_predicates.retain(|pred| {
549 clean::WherePredicate::BoundPredicate {
550 ty: clean::Generic(ref s),
552 } if *s == "Self" => {
553 ty_bounds.extend(bounds.iter().cloned());