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.
15 use syntax::attr::AttrMetaMethods;
17 use rustc::metadata::csearch;
18 use rustc::metadata::decoder;
19 use rustc::middle::def;
20 use rustc::middle::ty;
21 use rustc::middle::subst;
22 use rustc::middle::stability;
30 /// Attempt to inline the definition of a local node id into this AST.
32 /// This function will fetch the definition of the id specified, and if it is
33 /// from another crate it will attempt to inline the documentation from the
34 /// other crate into this crate.
36 /// This is primarily used for `pub use` statements which are, in general,
37 /// implementation details. Inlining the documentation should help provide a
38 /// better experience when reading the documentation in this use case.
40 /// The returned value is `None` if the `id` could not be inlined, and `Some`
41 /// of a vector of items if it was successfully expanded.
42 pub fn try_inline(cx: &DocContext, id: ast::NodeId, into: Option<ast::Ident>)
43 -> Option<Vec<clean::Item>> {
44 let tcx = match cx.tcx_opt() {
48 let def = match tcx.def_map.borrow().get(&id) {
52 let did = def.def_id();
53 if ast_util::is_local(did) { return None }
54 try_inline_def(cx, tcx, def).map(|vec| {
55 vec.into_iter().map(|mut item| {
57 Some(into) if item.name.is_some() => {
58 item.name = Some(into.clean(cx));
67 fn try_inline_def(cx: &DocContext, tcx: &ty::ctxt,
68 def: def::Def) -> Option<Vec<clean::Item>> {
69 let mut ret = Vec::new();
70 let did = def.def_id();
71 let inner = match def {
72 def::DefTrait(did) => {
73 record_extern_fqn(cx, did, clean::TypeTrait);
74 clean::TraitItem(build_external_trait(cx, tcx, did))
76 def::DefFn(did, false) => {
77 // If this function is a tuple struct constructor, we just skip it
78 record_extern_fqn(cx, did, clean::TypeFunction);
79 clean::FunctionItem(build_external_function(cx, tcx, did))
81 def::DefStruct(did) => {
82 record_extern_fqn(cx, did, clean::TypeStruct);
83 ret.extend(build_impls(cx, tcx, did).into_iter());
84 clean::StructItem(build_struct(cx, tcx, did))
86 def::DefTy(did, false) => {
87 record_extern_fqn(cx, did, clean::TypeTypedef);
88 ret.extend(build_impls(cx, tcx, did).into_iter());
89 build_type(cx, tcx, did)
91 def::DefTy(did, true) => {
92 record_extern_fqn(cx, did, clean::TypeEnum);
93 ret.extend(build_impls(cx, tcx, did).into_iter());
94 build_type(cx, tcx, did)
96 // Assume that the enum type is reexported next to the variant, and
97 // variants don't show up in documentation specially.
98 def::DefVariant(..) => return Some(Vec::new()),
100 record_extern_fqn(cx, did, clean::TypeModule);
101 clean::ModuleItem(build_module(cx, tcx, did))
103 def::DefStatic(did, mtbl) => {
104 record_extern_fqn(cx, did, clean::TypeStatic);
105 clean::StaticItem(build_static(cx, tcx, did, mtbl))
107 def::DefConst(did) => {
108 record_extern_fqn(cx, did, clean::TypeConst);
109 clean::ConstantItem(build_const(cx, tcx, did))
113 let fqn = csearch::get_item_path(tcx, did);
114 cx.inlined.borrow_mut().as_mut().unwrap().insert(did);
115 ret.push(clean::Item {
116 source: clean::Span::empty(),
117 name: Some(fqn.last().unwrap().to_string()),
118 attrs: load_attrs(cx, tcx, did),
120 visibility: Some(ast::Public),
121 stability: stability::lookup(tcx, did).clean(cx),
127 pub fn load_attrs(cx: &DocContext, tcx: &ty::ctxt,
128 did: ast::DefId) -> Vec<clean::Attribute> {
129 let attrs = csearch::get_item_attrs(&tcx.sess.cstore, did);
130 attrs.into_iter().map(|a| a.clean(cx)).collect()
133 /// Record an external fully qualified name in the external_paths cache.
135 /// These names are used later on by HTML rendering to generate things like
136 /// source links back to the original item.
137 pub fn record_extern_fqn(cx: &DocContext, did: ast::DefId, kind: clean::TypeKind) {
140 let fqn = csearch::get_item_path(tcx, did);
141 let fqn = fqn.into_iter().map(|i| i.to_string()).collect();
142 cx.external_paths.borrow_mut().as_mut().unwrap().insert(did, (fqn, kind));
148 pub fn build_external_trait(cx: &DocContext, tcx: &ty::ctxt,
149 did: ast::DefId) -> clean::Trait {
150 use clean::TraitMethod;
152 let def = ty::lookup_trait_def(tcx, did);
153 let trait_items = ty::trait_items(tcx, did).clean(cx);
154 let provided = ty::provided_trait_methods(tcx, did);
155 let items = trait_items.into_iter().map(|trait_item| {
156 match trait_item.inner {
157 clean::TyMethodItem(_) => {
158 if provided.iter().any(|a| a.def_id == trait_item.def_id) {
159 TraitMethod::ProvidedMethod(trait_item)
161 TraitMethod::RequiredMethod(trait_item)
164 clean::AssociatedTypeItem(_) => TraitMethod::TypeTraitItem(trait_item),
168 let trait_def = ty::lookup_trait_def(tcx, did);
169 let bounds = trait_def.bounds.clean(cx);
171 unsafety: def.unsafety,
172 generics: (&def.generics, subst::TypeSpace).clean(cx),
173 items: items.collect(),
178 fn build_external_function(cx: &DocContext, tcx: &ty::ctxt, did: ast::DefId) -> clean::Function {
179 let t = ty::lookup_item_type(tcx, did);
180 let (decl, style) = match t.ty.sty {
181 ty::ty_bare_fn(_, ref f) => ((did, &f.sig).clean(cx), f.unsafety),
182 _ => panic!("bad function"),
186 generics: (&t.generics, subst::FnSpace).clean(cx),
191 fn build_struct(cx: &DocContext, tcx: &ty::ctxt, did: ast::DefId) -> clean::Struct {
192 use syntax::parse::token::special_idents::unnamed_field;
194 let t = ty::lookup_item_type(tcx, did);
195 let fields = ty::lookup_struct_fields(tcx, did);
198 struct_type: match fields.as_slice() {
200 [ref f] if f.name == unnamed_field.name => doctree::Newtype,
201 [ref f, ..] if f.name == unnamed_field.name => doctree::Tuple,
204 generics: (&t.generics, subst::TypeSpace).clean(cx),
205 fields: fields.clean(cx),
206 fields_stripped: false,
210 fn build_type(cx: &DocContext, tcx: &ty::ctxt, did: ast::DefId) -> clean::ItemEnum {
211 let t = ty::lookup_item_type(tcx, did);
213 ty::ty_enum(edid, _) if !csearch::is_typedef(&tcx.sess.cstore, did) => {
214 return clean::EnumItem(clean::Enum {
215 generics: (&t.generics, subst::TypeSpace).clean(cx),
216 variants_stripped: false,
217 variants: ty::enum_variants(tcx, edid).clean(cx),
223 clean::TypedefItem(clean::Typedef {
224 type_: t.ty.clean(cx),
225 generics: (&t.generics, subst::TypeSpace).clean(cx),
229 fn build_impls(cx: &DocContext, tcx: &ty::ctxt,
230 did: ast::DefId) -> Vec<clean::Item> {
231 ty::populate_implementations_for_type_if_necessary(tcx, did);
232 let mut impls = Vec::new();
234 match tcx.inherent_impls.borrow().get(&did) {
237 impls.extend(i.iter().map(|&did| { build_impl(cx, tcx, did) }));
241 // If this is the first time we've inlined something from this crate, then
242 // we inline *all* impls from the crate into this crate. Note that there's
243 // currently no way for us to filter this based on type, and we likely need
244 // many impls for a variety of reasons.
246 // Primarily, the impls will be used to populate the documentation for this
247 // type being inlined, but impls can also be used when generating
248 // documentation for primitives (no way to find those specifically).
249 if cx.populated_crate_impls.borrow_mut().insert(did.krate) {
250 csearch::each_top_level_item_of_crate(&tcx.sess.cstore,
253 populate_impls(cx, tcx, def, &mut impls)
256 fn populate_impls(cx: &DocContext, tcx: &ty::ctxt,
257 def: decoder::DefLike,
258 impls: &mut Vec<Option<clean::Item>>) {
260 decoder::DlImpl(did) => impls.push(build_impl(cx, tcx, did)),
261 decoder::DlDef(def::DefMod(did)) => {
262 csearch::each_child_of_item(&tcx.sess.cstore,
265 populate_impls(cx, tcx, def, impls)
273 impls.into_iter().filter_map(|a| a).collect()
276 fn build_impl(cx: &DocContext, tcx: &ty::ctxt,
277 did: ast::DefId) -> Option<clean::Item> {
278 if !cx.inlined.borrow_mut().as_mut().unwrap().insert(did) {
282 let associated_trait = csearch::get_impl_trait(tcx, did);
283 // If this is an impl for a #[doc(hidden)] trait, be sure to not inline it.
284 match associated_trait {
286 let trait_attrs = load_attrs(cx, tcx, t.def_id);
287 if trait_attrs.iter().any(|a| is_doc_hidden(a)) {
294 let attrs = load_attrs(cx, tcx, did);
295 let ty = ty::lookup_item_type(tcx, did);
296 let trait_items = csearch::get_impl_items(&tcx.sess.cstore, did)
299 let did = did.def_id();
300 let impl_item = ty::impl_or_trait_item(tcx, did);
302 ty::MethodTraitItem(method) => {
303 if method.vis != ast::Public && associated_trait.is_none() {
306 let mut item = method.clean(cx);
307 item.inner = match item.inner.clone() {
308 clean::TyMethodItem(clean::TyMethod {
309 unsafety, decl, self_, generics
311 clean::MethodItem(clean::Method {
318 _ => panic!("not a tymethod"),
322 ty::TypeTraitItem(ref assoc_ty) => {
323 let did = assoc_ty.def_id;
324 let type_scheme = ty::lookup_item_type(tcx, did);
325 // Not sure the choice of ParamSpace actually matters here, because an
326 // associated type won't have generics on the LHS
327 let typedef = (type_scheme, subst::ParamSpace::TypeSpace).clean(cx);
329 name: Some(assoc_ty.name.clean(cx)),
330 inner: clean::TypedefItem(typedef),
331 source: clean::Span::empty(),
334 stability: stability::lookup(tcx, did).clean(cx),
340 let polarity = csearch::get_impl_polarity(tcx, did);
341 return Some(clean::Item {
342 inner: clean::ImplItem(clean::Impl {
343 derived: clean::detect_derived(attrs.as_slice()),
344 trait_: associated_trait.clean(cx).map(|bound| {
346 clean::TraitBound(polyt, _) => polyt.trait_,
347 clean::RegionBound(..) => unreachable!(),
350 for_: ty.ty.clean(cx),
351 generics: (&ty.generics, subst::TypeSpace).clean(cx),
353 polarity: polarity.map(|p| { p.clean(cx) }),
355 source: clean::Span::empty(),
358 visibility: Some(ast::Inherited),
359 stability: stability::lookup(tcx, did).clean(cx),
363 fn is_doc_hidden(a: &clean::Attribute) -> bool {
365 clean::List(ref name, ref inner) if *name == "doc" => {
366 inner.iter().any(|a| {
368 clean::Word(ref s) => *s == "hidden",
378 fn build_module(cx: &DocContext, tcx: &ty::ctxt,
379 did: ast::DefId) -> clean::Module {
380 let mut items = Vec::new();
381 fill_in(cx, tcx, did, &mut items);
382 return clean::Module {
387 // FIXME: this doesn't handle reexports inside the module itself.
388 // Should they be handled?
389 fn fill_in(cx: &DocContext, tcx: &ty::ctxt, did: ast::DefId,
390 items: &mut Vec<clean::Item>) {
391 csearch::each_child_of_item(&tcx.sess.cstore, did, |def, _, vis| {
393 decoder::DlDef(def::DefForeignMod(did)) => {
394 fill_in(cx, tcx, did, items);
396 decoder::DlDef(def) if vis == ast::Public => {
397 match try_inline_def(cx, tcx, def) {
398 Some(i) => items.extend(i.into_iter()),
402 decoder::DlDef(..) => {}
403 // All impls were inlined above
404 decoder::DlImpl(..) => {}
405 decoder::DlField => panic!("unimplemented field"),
411 fn build_const(cx: &DocContext, tcx: &ty::ctxt,
412 did: ast::DefId) -> clean::Constant {
413 use rustc::middle::const_eval;
414 use syntax::print::pprust;
416 let expr = const_eval::lookup_const_by_id(tcx, did).unwrap_or_else(|| {
417 panic!("expected lookup_const_by_id to succeed for {:?}", did);
419 debug!("converting constant expr {:?} to snippet", expr);
420 let sn = pprust::expr_to_string(expr);
421 debug!("got snippet {}", sn);
424 type_: ty::lookup_item_type(tcx, did).ty.clean(cx),
429 fn build_static(cx: &DocContext, tcx: &ty::ctxt,
431 mutable: bool) -> clean::Static {
433 type_: ty::lookup_item_type(tcx, did).ty.clean(cx),
434 mutability: if mutable {clean::Mutable} else {clean::Immutable},
435 expr: "\n\n\n".to_string(), // trigger the "[definition]" links