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 clean::MacroItem(build_macro(cx, did, name))
111 cx.renderinfo.borrow_mut().inlined.insert(did);
112 ret.push(clean::Item {
113 source: cx.tcx.def_span(did).clean(cx),
114 name: Some(name.clean(cx)),
115 attrs: load_attrs(cx, did),
117 visibility: Some(clean::Public),
118 stability: cx.tcx.lookup_stability(did).clean(cx),
119 deprecation: cx.tcx.lookup_deprecation(did).clean(cx),
125 pub fn try_inline_glob(cx: &DocContext, def: Def, visited: &mut FxHashSet<DefId>)
126 -> Option<Vec<clean::Item>>
128 if def == Def::Err { return None }
129 let did = def.def_id();
130 if did.is_local() { return None }
134 let m = build_module(cx, did, visited);
137 // glob imports on things like enums aren't inlined even for local exports, so just bail
142 pub fn load_attrs(cx: &DocContext, did: DefId) -> clean::Attributes {
143 cx.tcx.get_attrs(did).clean(cx)
146 /// Record an external fully qualified name in the external_paths cache.
148 /// These names are used later on by HTML rendering to generate things like
149 /// source links back to the original item.
150 pub fn record_extern_fqn(cx: &DocContext, did: DefId, kind: clean::TypeKind) {
152 debug!("record_extern_fqn(did={:?}, kind+{:?}): def_id is local, aborting", did, kind);
156 let crate_name = cx.tcx.crate_name(did.krate).to_string();
157 let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
158 // extern blocks have an empty name
159 let s = elem.data.to_string();
166 let fqn = if let clean::TypeKind::Macro = kind {
167 vec![crate_name, relative.last().unwrap()]
169 once(crate_name).chain(relative).collect()
171 cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind));
174 pub fn build_external_trait(cx: &DocContext, did: DefId) -> clean::Trait {
175 let auto_trait = cx.tcx.trait_def(did).has_auto_impl;
176 let trait_items = cx.tcx.associated_items(did).map(|item| item.clean(cx)).collect();
177 let predicates = cx.tcx.predicates_of(did);
178 let generics = (cx.tcx.generics_of(did), &predicates).clean(cx);
179 let generics = filter_non_trait_generics(did, generics);
180 let (generics, supertrait_bounds) = separate_supertrait_bounds(generics);
181 let is_spotlight = load_attrs(cx, did).has_doc_flag("spotlight");
182 let is_auto = cx.tcx.trait_is_auto(did);
185 unsafety: cx.tcx.trait_def(did).unsafety,
188 bounds: supertrait_bounds,
194 fn build_external_function(cx: &DocContext, did: DefId) -> clean::Function {
195 let sig = cx.tcx.fn_sig(did);
197 let constness = if cx.tcx.is_const_fn(did) {
198 hir::Constness::Const
200 hir::Constness::NotConst
203 let predicates = cx.tcx.predicates_of(did);
205 decl: (did, sig).clean(cx),
206 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
207 header: hir::FnHeader {
208 unsafety: sig.unsafety(),
211 asyncness: hir::IsAsync::NotAsync,
216 fn build_enum(cx: &DocContext, did: DefId) -> clean::Enum {
217 let predicates = cx.tcx.predicates_of(did);
220 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
221 variants_stripped: false,
222 variants: cx.tcx.adt_def(did).variants.clean(cx),
226 fn build_struct(cx: &DocContext, did: DefId) -> clean::Struct {
227 let predicates = cx.tcx.predicates_of(did);
228 let variant = cx.tcx.adt_def(did).non_enum_variant();
231 struct_type: match variant.ctor_kind {
232 CtorKind::Fictive => doctree::Plain,
233 CtorKind::Fn => doctree::Tuple,
234 CtorKind::Const => doctree::Unit,
236 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
237 fields: variant.fields.clean(cx),
238 fields_stripped: false,
242 fn build_union(cx: &DocContext, did: DefId) -> clean::Union {
243 let predicates = cx.tcx.predicates_of(did);
244 let variant = cx.tcx.adt_def(did).non_enum_variant();
247 struct_type: doctree::Plain,
248 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
249 fields: variant.fields.clean(cx),
250 fields_stripped: false,
254 fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
255 let predicates = cx.tcx.predicates_of(did);
258 type_: cx.tcx.type_of(did).clean(cx),
259 generics: (cx.tcx.generics_of(did), &predicates).clean(cx),
263 pub fn build_impls(cx: &DocContext, did: DefId, auto_traits: bool) -> Vec<clean::Item> {
265 let mut impls = Vec::new();
267 for &did in tcx.inherent_impls(did).iter() {
268 build_impl(cx, did, &mut impls);
272 let auto_impls = get_auto_traits_with_def_id(cx, did);
273 let mut renderinfo = cx.renderinfo.borrow_mut();
275 let new_impls: Vec<clean::Item> = auto_impls.into_iter()
276 .filter(|i| renderinfo.inlined.insert(i.def_id)).collect();
278 impls.extend(new_impls);
281 // If this is the first time we've inlined something from another crate, then
282 // we inline *all* impls from all the crates into this crate. Note that there's
283 // currently no way for us to filter this based on type, and we likely need
284 // many impls for a variety of reasons.
286 // Primarily, the impls will be used to populate the documentation for this
287 // type being inlined, but impls can also be used when generating
288 // documentation for primitives (no way to find those specifically).
289 if cx.populated_all_crate_impls.get() {
293 cx.populated_all_crate_impls.set(true);
295 for &cnum in tcx.crates().iter() {
296 for did in tcx.all_trait_implementations(cnum).iter() {
297 build_impl(cx, *did, &mut impls);
301 // Also try to inline primitive impls from other crates.
302 let lang_items = tcx.lang_items();
303 let primitive_impls = [
304 lang_items.isize_impl(),
305 lang_items.i8_impl(),
306 lang_items.i16_impl(),
307 lang_items.i32_impl(),
308 lang_items.i64_impl(),
309 lang_items.i128_impl(),
310 lang_items.usize_impl(),
311 lang_items.u8_impl(),
312 lang_items.u16_impl(),
313 lang_items.u32_impl(),
314 lang_items.u64_impl(),
315 lang_items.u128_impl(),
316 lang_items.f32_impl(),
317 lang_items.f64_impl(),
318 lang_items.f32_runtime_impl(),
319 lang_items.f64_runtime_impl(),
320 lang_items.char_impl(),
321 lang_items.str_impl(),
322 lang_items.slice_impl(),
323 lang_items.slice_u8_impl(),
324 lang_items.str_alloc_impl(),
325 lang_items.slice_alloc_impl(),
326 lang_items.slice_u8_alloc_impl(),
327 lang_items.const_ptr_impl(),
328 lang_items.mut_ptr_impl(),
331 for def_id in primitive_impls.iter().filter_map(|&def_id| def_id) {
332 if !def_id.is_local() {
333 build_impl(cx, def_id, &mut impls);
335 let auto_impls = get_auto_traits_with_def_id(cx, def_id);
336 let mut renderinfo = cx.renderinfo.borrow_mut();
338 let new_impls: Vec<clean::Item> = auto_impls.into_iter()
339 .filter(|i| renderinfo.inlined.insert(i.def_id)).collect();
341 impls.extend(new_impls);
348 pub fn build_impl(cx: &DocContext, did: DefId, ret: &mut Vec<clean::Item>) {
349 if !cx.renderinfo.borrow_mut().inlined.insert(did) {
353 let attrs = load_attrs(cx, did);
355 let associated_trait = tcx.impl_trait_ref(did);
357 // Only inline impl if the implemented trait is
358 // reachable in rustdoc generated documentation
359 if let Some(traitref) = associated_trait {
360 if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) {
365 let for_ = tcx.type_of(did).clean(cx);
367 // Only inline impl if the implementing type is
368 // reachable in rustdoc generated documentation
369 if let Some(did) = for_.def_id() {
370 if !cx.access_levels.borrow().is_doc_reachable(did) {
375 let predicates = tcx.predicates_of(did);
376 let trait_items = tcx.associated_items(did).filter_map(|item| {
377 if associated_trait.is_some() || item.vis == ty::Visibility::Public {
382 }).collect::<Vec<_>>();
383 let polarity = tcx.impl_polarity(did);
384 let trait_ = associated_trait.clean(cx).map(|bound| {
386 clean::GenericBound::TraitBound(polyt, _) => polyt.trait_,
387 clean::GenericBound::Outlives(..) => unreachable!(),
390 if trait_.def_id() == tcx.lang_items().deref_trait() {
391 super::build_deref_target_impls(cx, &trait_items, ret);
393 if let Some(trait_did) = trait_.def_id() {
394 record_extern_trait(cx, trait_did);
397 let provided = trait_.def_id().map(|did| {
398 tcx.provided_trait_methods(did)
400 .map(|meth| meth.ident.to_string())
402 }).unwrap_or(FxHashSet());
404 ret.push(clean::Item {
405 inner: clean::ImplItem(clean::Impl {
406 unsafety: hir::Unsafety::Normal,
407 generics: (tcx.generics_of(did), &predicates).clean(cx),
408 provided_trait_methods: provided,
412 polarity: Some(polarity.clean(cx)),
415 source: tcx.def_span(did).clean(cx),
418 visibility: Some(clean::Inherited),
419 stability: tcx.lookup_stability(did).clean(cx),
420 deprecation: tcx.lookup_deprecation(did).clean(cx),
425 fn build_module(cx: &DocContext, did: DefId, visited: &mut FxHashSet<DefId>) -> clean::Module {
426 let mut items = Vec::new();
427 fill_in(cx, did, &mut items, visited);
428 return clean::Module {
433 fn fill_in(cx: &DocContext, did: DefId, items: &mut Vec<clean::Item>,
434 visited: &mut FxHashSet<DefId>) {
435 // If we're re-exporting a re-export it may actually re-export something in
436 // two namespaces, so the target may be listed twice. Make sure we only
437 // visit each node at most once.
438 for &item in cx.tcx.item_children(did).iter() {
439 let def_id = item.def.def_id();
440 if item.vis == ty::Visibility::Public {
441 if did == def_id || !visited.insert(def_id) { continue }
442 if let Some(i) = try_inline(cx, item.def, item.ident.name, visited) {
450 pub fn print_inlined_const(cx: &DocContext, did: DefId) -> String {
451 cx.tcx.rendered_const(did)
454 fn build_const(cx: &DocContext, did: DefId) -> clean::Constant {
456 type_: cx.tcx.type_of(did).clean(cx),
457 expr: print_inlined_const(cx, did)
461 fn build_static(cx: &DocContext, did: DefId, mutable: bool) -> clean::Static {
463 type_: cx.tcx.type_of(did).clean(cx),
464 mutability: if mutable {clean::Mutable} else {clean::Immutable},
465 expr: "\n\n\n".to_string(), // trigger the "[definition]" links
469 fn build_macro(cx: &DocContext, did: DefId, name: ast::Name) -> clean::Macro {
470 let imported_from = cx.tcx.original_crate_name(did.krate);
471 let def = match cx.cstore.load_macro_untracked(did, cx.sess()) {
472 LoadedMacro::MacroDef(macro_def) => macro_def,
473 // FIXME(jseyfried): document proc macro re-exports
474 LoadedMacro::ProcMacro(..) => panic!("attempting to document proc-macro re-export"),
477 let matchers: hir::HirVec<Span> = if let ast::ItemKind::MacroDef(ref def) = def.node {
478 let tts: Vec<_> = def.stream().into_trees().collect();
479 tts.chunks(4).map(|arm| arm[0].span()).collect()
484 let source = format!("macro_rules! {} {{\n{}}}",
486 matchers.iter().map(|span| {
487 format!(" {} => {{ ... }};\n", span.to_src(cx))
488 }).collect::<String>());
492 imported_from: Some(imported_from).clean(cx),
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 generating 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) -> clean::Generics {
505 for pred in &mut g.where_predicates {
507 clean::WherePredicate::BoundPredicate {
508 ty: clean::Generic(ref s),
510 } if *s == "Self" => {
511 bounds.retain(|bound| {
513 clean::GenericBound::TraitBound(clean::PolyTrait {
514 trait_: clean::ResolvedPath { did, .. },
516 }, _) => did != trait_did,
525 g.where_predicates.retain(|pred| {
527 clean::WherePredicate::BoundPredicate {
529 self_type: box clean::Generic(ref s),
530 trait_: box clean::ResolvedPath { did, .. },
533 } => !(*s == "Self" && did == trait_did) && !bounds.is_empty(),
540 /// Supertrait bounds for a trait are also listed in the generics coming from
541 /// the metadata for a crate, so we want to separate those out and create a new
542 /// list of explicit supertrait bounds to render nicely.
543 fn separate_supertrait_bounds(mut g: clean::Generics)
544 -> (clean::Generics, Vec<clean::GenericBound>) {
545 let mut ty_bounds = Vec::new();
546 g.where_predicates.retain(|pred| {
548 clean::WherePredicate::BoundPredicate {
549 ty: clean::Generic(ref s),
551 } if *s == "Self" => {
552 ty_bounds.extend(bounds.iter().cloned());
561 pub fn record_extern_trait(cx: &DocContext, did: DefId) {
562 if cx.external_traits.borrow().contains_key(&did) ||
563 cx.active_extern_traits.borrow().contains(&did)
568 cx.active_extern_traits.borrow_mut().push(did);
570 let trait_ = build_external_trait(cx, did);
572 cx.external_traits.borrow_mut().insert(did, trait_);
573 cx.active_extern_traits.borrow_mut().remove_item(&did);