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.
16 use syntax::ext::base::MacroKind;
20 use rustc::hir::def::{Def, CtorKind};
21 use rustc::hir::def_id::DefId;
22 use rustc::middle::cstore::LoadedMacro;
24 use rustc::util::nodemap::FxHashSet;
26 use core::{DocContext, DocAccessLevels};
28 use clean::{self, GetDefId, ToSource, 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, visited: &mut FxHashSet<DefId>)
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, visited))
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))
103 // FIXME(misdreavus): if attributes/derives come down here we should probably document them
105 Def::Macro(did, MacroKind::Bang) => {
106 record_extern_fqn(cx, did, clean::TypeKind::Macro);
107 if let Some(mac) = build_macro(cx, did, name) {
108 clean::MacroItem(mac)
115 cx.renderinfo.borrow_mut().inlined.insert(did);
116 ret.push(clean::Item {
117 source: cx.tcx.def_span(did).clean(cx),
118 name: Some(name.clean(cx)),
119 attrs: load_attrs(cx, did),
121 visibility: Some(clean::Public),
122 stability: cx.tcx.lookup_stability(did).clean(cx),
123 deprecation: cx.tcx.lookup_deprecation(did).clean(cx),
129 pub fn try_inline_glob(cx: &DocContext, def: Def, visited: &mut FxHashSet<DefId>)
130 -> Option<Vec<clean::Item>>
132 if def == Def::Err { return None }
133 let did = def.def_id();
134 if did.is_local() { return None }
138 let m = build_module(cx, did, visited);
141 // glob imports on things like enums aren't inlined even for local exports, so just bail
146 pub fn load_attrs(cx: &DocContext, did: DefId) -> clean::Attributes {
147 cx.tcx.get_attrs(did).clean(cx)
150 /// Record an external fully qualified name in the external_paths cache.
152 /// These names are used later on by HTML rendering to generate things like
153 /// source links back to the original item.
154 pub fn record_extern_fqn(cx: &DocContext, did: DefId, kind: clean::TypeKind) {
156 debug!("record_extern_fqn(did={:?}, kind+{:?}): def_id is local, aborting", did, kind);
160 let crate_name = cx.tcx.crate_name(did.krate).to_string();
161 let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
162 // extern blocks have an empty name
163 let s = elem.data.to_string();
170 let fqn = if let clean::TypeKind::Macro = kind {
171 vec![crate_name, relative.last().unwrap()]
173 once(crate_name).chain(relative).collect()
175 cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind));
178 pub fn build_external_trait(cx: &DocContext, did: DefId) -> clean::Trait {
179 let auto_trait = cx.tcx.trait_def(did).has_auto_impl;
180 let trait_items = cx.tcx.associated_items(did).map(|item| item.clean(cx)).collect();
181 let predicates = cx.tcx.predicates_of(did);
182 let generics = (cx.tcx.generics_of(did), &predicates).clean(cx);
183 let generics = filter_non_trait_generics(did, generics);
184 let (generics, supertrait_bounds) = separate_supertrait_bounds(generics);
185 let is_spotlight = load_attrs(cx, did).has_doc_flag("spotlight");
186 let is_auto = cx.tcx.trait_is_auto(did);
189 unsafety: cx.tcx.trait_def(did).unsafety,
192 bounds: supertrait_bounds,
198 fn build_external_function(cx: &DocContext, did: DefId) -> clean::Function {
199 let sig = cx.tcx.fn_sig(did);
201 let constness = if cx.tcx.is_const_fn(did) {
202 hir::Constness::Const
204 hir::Constness::NotConst
207 let predicates = cx.tcx.predicates_of(did);
209 decl: (did, sig).clean(cx),
210 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
211 header: hir::FnHeader {
212 unsafety: sig.unsafety(),
215 asyncness: hir::IsAsync::NotAsync,
220 fn build_enum(cx: &DocContext, did: DefId) -> clean::Enum {
221 let predicates = cx.tcx.predicates_of(did);
224 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
225 variants_stripped: false,
226 variants: cx.tcx.adt_def(did).variants.clean(cx),
230 fn build_struct(cx: &DocContext, did: DefId) -> clean::Struct {
231 let predicates = cx.tcx.predicates_of(did);
232 let variant = cx.tcx.adt_def(did).non_enum_variant();
235 struct_type: match variant.ctor_kind {
236 CtorKind::Fictive => doctree::Plain,
237 CtorKind::Fn => doctree::Tuple,
238 CtorKind::Const => doctree::Unit,
240 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
241 fields: variant.fields.clean(cx),
242 fields_stripped: false,
246 fn build_union(cx: &DocContext, did: DefId) -> clean::Union {
247 let predicates = cx.tcx.predicates_of(did);
248 let variant = cx.tcx.adt_def(did).non_enum_variant();
251 struct_type: doctree::Plain,
252 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
253 fields: variant.fields.clean(cx),
254 fields_stripped: false,
258 fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
259 let predicates = cx.tcx.predicates_of(did);
262 type_: cx.tcx.type_of(did).clean(cx),
263 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
267 pub fn build_impls(cx: &DocContext, did: DefId, auto_traits: bool) -> Vec<clean::Item> {
269 let mut impls = Vec::new();
271 for &did in tcx.inherent_impls(did).iter() {
272 build_impl(cx, did, &mut impls);
276 let auto_impls = get_auto_traits_with_def_id(cx, did);
277 let mut renderinfo = cx.renderinfo.borrow_mut();
278 let new_impls: Vec<clean::Item> = auto_impls.into_iter()
279 .filter(|i| renderinfo.inlined.insert(i.def_id)).collect();
281 impls.extend(new_impls);
284 // If this is the first time we've inlined something from another crate, then
285 // we inline *all* impls from all the crates into this crate. Note that there's
286 // currently no way for us to filter this based on type, and we likely need
287 // many impls for a variety of reasons.
289 // Primarily, the impls will be used to populate the documentation for this
290 // type being inlined, but impls can also be used when generating
291 // documentation for primitives (no way to find those specifically).
292 if cx.populated_all_crate_impls.get() {
296 cx.populated_all_crate_impls.set(true);
298 for &cnum in tcx.crates().iter() {
299 for did in tcx.all_trait_implementations(cnum).iter() {
300 build_impl(cx, *did, &mut impls);
304 // Also try to inline primitive impls from other crates.
305 let lang_items = tcx.lang_items();
306 let primitive_impls = [
307 lang_items.isize_impl(),
308 lang_items.i8_impl(),
309 lang_items.i16_impl(),
310 lang_items.i32_impl(),
311 lang_items.i64_impl(),
312 lang_items.i128_impl(),
313 lang_items.usize_impl(),
314 lang_items.u8_impl(),
315 lang_items.u16_impl(),
316 lang_items.u32_impl(),
317 lang_items.u64_impl(),
318 lang_items.u128_impl(),
319 lang_items.f32_impl(),
320 lang_items.f64_impl(),
321 lang_items.f32_runtime_impl(),
322 lang_items.f64_runtime_impl(),
323 lang_items.char_impl(),
324 lang_items.str_impl(),
325 lang_items.slice_impl(),
326 lang_items.slice_u8_impl(),
327 lang_items.str_alloc_impl(),
328 lang_items.slice_alloc_impl(),
329 lang_items.slice_u8_alloc_impl(),
330 lang_items.const_ptr_impl(),
331 lang_items.mut_ptr_impl(),
334 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
335 if !def_id.is_local() {
336 build_impl(cx, def_id, &mut impls);
338 let auto_impls = get_auto_traits_with_def_id(cx, def_id);
339 let mut renderinfo = cx.renderinfo.borrow_mut();
341 let new_impls: Vec<clean::Item> = auto_impls.into_iter()
342 .filter(|i| renderinfo.inlined.insert(i.def_id)).collect();
344 impls.extend(new_impls);
351 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
352 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
356 let attrs = load_attrs(cx, did);
358 let associated_trait = tcx.impl_trait_ref(did);
360 // Only inline impl if the implemented trait is
361 // reachable in rustdoc generated documentation
362 if let Some(traitref) = associated_trait {
363 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
368 let for_ = tcx.type_of(did).clean(cx);
370 // Only inline impl if the implementing type is
371 // reachable in rustdoc generated documentation
372 if let Some(did) = for_.def_id() {
373 if !cx.access_levels.borrow().is_doc_reachable(did) {
378 let predicates = tcx.predicates_of(did);
379 let trait_items = tcx.associated_items(did).filter_map(|item| {
380 if associated_trait.is_some() || item.vis == ty::Visibility::Public {
385 }).collect::<Vec<_>>();
386 let polarity = tcx.impl_polarity(did);
387 let trait_ = associated_trait.clean(cx).map(|bound| {
389 clean::GenericBound::TraitBound(polyt, _) => polyt.trait_,
390 clean::GenericBound::Outlives(..) => unreachable!(),
393 if trait_.def_id() == tcx.lang_items().deref_trait() {
394 super::build_deref_target_impls(cx, &trait_items, ret);
396 if let Some(trait_did) = trait_.def_id() {
397 record_extern_trait(cx, trait_did);
400 let provided = trait_.def_id().map(|did| {
401 tcx.provided_trait_methods(did)
403 .map(|meth| meth.ident.to_string())
405 }).unwrap_or(FxHashSet());
407 ret.push(clean::Item {
408 inner: clean::ImplItem(clean::Impl {
409 unsafety: hir::Unsafety::Normal,
410 generics: (tcx.generics_of(did), &predicates).clean(cx),
411 provided_trait_methods: provided,
415 polarity: Some(polarity.clean(cx)),
418 source: tcx.def_span(did).clean(cx),
421 visibility: Some(clean::Inherited),
422 stability: tcx.lookup_stability(did).clean(cx),
423 deprecation: tcx.lookup_deprecation(did).clean(cx),
428 fn build_module(cx: &DocContext, did: DefId, visited: &mut FxHashSet<DefId>) -> clean::Module {
429 let mut items = Vec::new();
430 fill_in(cx, did, &mut items, visited);
431 return clean::Module {
436 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>,
437 visited: &mut FxHashSet<DefId>) {
438 // If we're re-exporting a re-export it may actually re-export something in
439 // two namespaces, so the target may be listed twice. Make sure we only
440 // visit each node at most once.
441 for &item in cx.tcx.item_children(did).iter() {
442 let def_id = item.def.def_id();
443 if item.vis == ty::Visibility::Public {
444 if did == def_id || !visited.insert(def_id) { continue }
445 if let Some(i) = try_inline(cx, item.def, item.ident.name, visited) {
453 pub fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
454 cx.tcx.rendered_const(did)
457 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
459 type_: cx.tcx.type_of(did).clean(cx),
460 expr: print_inlined_const(cx, did)
464 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
466 type_: cx.tcx.type_of(did).clean(cx),
467 mutability: if mutable {clean::Mutable} else {clean::Immutable},
468 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
472 fn build_macro(cx: &DocContext, did: DefId, name: ast::Name) -> Option<clean::Macro> {
473 let imported_from = cx.tcx.original_crate_name(did.krate);
474 let def = match cx.cstore.load_macro_untracked(did, cx.sess()) {
475 LoadedMacro::MacroDef(macro_def) => macro_def,
476 // FIXME(jseyfried): document proc macro re-exports
477 LoadedMacro::ProcMacro(..) => return None,
480 let matchers: hir::HirVec<Span> = if let ast::ItemKind::MacroDef(ref def) = def.node {
481 let tts: Vec<_> = def.stream().into_trees().collect();
482 tts.chunks(4).map(|arm| arm[0].span()).collect()
487 let source = format!("macro_rules! {} {{\n{}}}",
489 matchers.iter().map(|span| {
490 format!(" {} => {{ ... }};\n", span.to_src(cx))
491 }).collect::<String>());
495 imported_from: Some(imported_from).clean(cx),
499 /// A trait's generics clause actually contains all of the predicates for all of
500 /// its associated types as well. We specifically move these clauses to the
501 /// associated types instead when displaying, so when we're generating the
502 /// generics for the trait itself we need to be sure to remove them.
503 /// We also need to remove the implied "recursive" Self: Trait bound.
505 /// The inverse of this filtering logic can be found in the `Clean`
506 /// implementation for `AssociatedType`
507 fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) -> 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::GenericBound::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::GenericBound>) {
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());
564 pub fn record_extern_trait(cx: &DocContext, did: DefId) {
565 if cx.external_traits.borrow().contains_key(&did) ||
566 cx.active_extern_traits.borrow().contains(&did)
571 cx.active_extern_traits.borrow_mut().push(did);
573 let trait_ = build_external_trait(cx, did);
575 cx.external_traits.borrow_mut().insert(did, trait_);
576 cx.active_extern_traits.borrow_mut().remove_item(&did);