| // Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! Support for inlining external documentation into the current AST. |
| |
| use std::collections::HashSet; |
| use std::iter::once; |
| |
| use syntax::ast; |
| use rustc::hir; |
| |
| use rustc::middle::cstore; |
| use rustc::hir::def::Def; |
| use rustc::hir::def_id::DefId; |
| use rustc::hir::print as pprust; |
| use rustc::ty::{self, TyCtxt}; |
| use rustc::ty::subst; |
| |
| use rustc_const_eval::lookup_const_by_id; |
| |
| use core::{DocContext, DocAccessLevels}; |
| use doctree; |
| use clean::{self, GetDefId}; |
| |
| use super::Clean; |
| |
| /// Attempt to inline the definition of a local node id into this AST. |
| /// |
| /// This function will fetch the definition of the id specified, and if it is |
| /// from another crate it will attempt to inline the documentation from the |
| /// other crate into this crate. |
| /// |
| /// This is primarily used for `pub use` statements which are, in general, |
| /// implementation details. Inlining the documentation should help provide a |
| /// better experience when reading the documentation in this use case. |
| /// |
| /// The returned value is `None` if the `id` could not be inlined, and `Some` |
| /// of a vector of items if it was successfully expanded. |
| pub fn try_inline(cx: &DocContext, id: ast::NodeId, into: Option<ast::Name>) |
| -> Option<Vec<clean::Item>> { |
| let tcx = match cx.tcx_opt() { |
| Some(tcx) => tcx, |
| None => return None, |
| }; |
| let def = match tcx.expect_def_or_none(id) { |
| Some(def) => def, |
| None => return None, |
| }; |
| let did = def.def_id(); |
| if did.is_local() { return None } |
| try_inline_def(cx, tcx, def).map(|vec| { |
| vec.into_iter().map(|mut item| { |
| match into { |
| Some(into) if item.name.is_some() => { |
| item.name = Some(into.clean(cx)); |
| } |
| _ => {} |
| } |
| item |
| }).collect() |
| }) |
| } |
| |
| fn try_inline_def<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| def: Def) -> Option<Vec<clean::Item>> { |
| let mut ret = Vec::new(); |
| let did = def.def_id(); |
| let inner = match def { |
| Def::Trait(did) => { |
| record_extern_fqn(cx, did, clean::TypeTrait); |
| ret.extend(build_impls(cx, tcx, did)); |
| clean::TraitItem(build_external_trait(cx, tcx, did)) |
| } |
| Def::Fn(did) => { |
| record_extern_fqn(cx, did, clean::TypeFunction); |
| clean::FunctionItem(build_external_function(cx, tcx, did)) |
| } |
| Def::Struct(did) |
| // If this is a struct constructor, we skip it |
| if tcx.sess.cstore.tuple_struct_definition_if_ctor(did).is_none() => { |
| record_extern_fqn(cx, did, clean::TypeStruct); |
| ret.extend(build_impls(cx, tcx, did)); |
| clean::StructItem(build_struct(cx, tcx, did)) |
| } |
| Def::TyAlias(did) => { |
| record_extern_fqn(cx, did, clean::TypeTypedef); |
| ret.extend(build_impls(cx, tcx, did)); |
| build_type(cx, tcx, did) |
| } |
| Def::Enum(did) => { |
| record_extern_fqn(cx, did, clean::TypeEnum); |
| ret.extend(build_impls(cx, tcx, did)); |
| build_type(cx, tcx, did) |
| } |
| // Assume that the enum type is reexported next to the variant, and |
| // variants don't show up in documentation specially. |
| Def::Variant(..) => return Some(Vec::new()), |
| Def::Mod(did) => { |
| record_extern_fqn(cx, did, clean::TypeModule); |
| clean::ModuleItem(build_module(cx, tcx, did)) |
| } |
| Def::Static(did, mtbl) => { |
| record_extern_fqn(cx, did, clean::TypeStatic); |
| clean::StaticItem(build_static(cx, tcx, did, mtbl)) |
| } |
| Def::Const(did) | Def::AssociatedConst(did) => { |
| record_extern_fqn(cx, did, clean::TypeConst); |
| clean::ConstantItem(build_const(cx, tcx, did)) |
| } |
| _ => return None, |
| }; |
| cx.renderinfo.borrow_mut().inlined.insert(did); |
| ret.push(clean::Item { |
| source: clean::Span::empty(), |
| name: Some(tcx.item_name(did).to_string()), |
| attrs: load_attrs(cx, tcx, did), |
| inner: inner, |
| visibility: Some(clean::Public), |
| stability: tcx.lookup_stability(did).clean(cx), |
| deprecation: tcx.lookup_deprecation(did).clean(cx), |
| def_id: did, |
| }); |
| Some(ret) |
| } |
| |
| pub fn load_attrs<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> Vec<clean::Attribute> { |
| tcx.get_attrs(did).iter().map(|a| a.clean(cx)).collect() |
| } |
| |
| /// Record an external fully qualified name in the external_paths cache. |
| /// |
| /// These names are used later on by HTML rendering to generate things like |
| /// source links back to the original item. |
| pub fn record_extern_fqn(cx: &DocContext, did: DefId, kind: clean::TypeKind) { |
| if let Some(tcx) = cx.tcx_opt() { |
| let crate_name = tcx.sess.cstore.crate_name(did.krate).to_string(); |
| let relative = tcx.def_path(did).data.into_iter().filter_map(|elem| { |
| // extern blocks have an empty name |
| let s = elem.data.to_string(); |
| if !s.is_empty() { |
| Some(s) |
| } else { |
| None |
| } |
| }); |
| let fqn = once(crate_name).chain(relative).collect(); |
| cx.renderinfo.borrow_mut().external_paths.insert(did, (fqn, kind)); |
| } |
| } |
| |
| pub fn build_external_trait<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::Trait { |
| let def = tcx.lookup_trait_def(did); |
| let trait_items = tcx.trait_items(did).clean(cx); |
| let predicates = tcx.lookup_predicates(did); |
| let generics = (&def.generics, &predicates, subst::TypeSpace).clean(cx); |
| let generics = filter_non_trait_generics(did, generics); |
| let (generics, supertrait_bounds) = separate_supertrait_bounds(generics); |
| clean::Trait { |
| unsafety: def.unsafety, |
| generics: generics, |
| items: trait_items, |
| bounds: supertrait_bounds, |
| } |
| } |
| |
| fn build_external_function<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::Function { |
| let t = tcx.lookup_item_type(did); |
| let (decl, style, abi) = match t.ty.sty { |
| ty::TyFnDef(_, _, ref f) => ((did, &f.sig).clean(cx), f.unsafety, f.abi), |
| _ => panic!("bad function"), |
| }; |
| |
| let constness = if tcx.sess.cstore.is_const_fn(did) { |
| hir::Constness::Const |
| } else { |
| hir::Constness::NotConst |
| }; |
| |
| let predicates = tcx.lookup_predicates(did); |
| clean::Function { |
| decl: decl, |
| generics: (&t.generics, &predicates, subst::FnSpace).clean(cx), |
| unsafety: style, |
| constness: constness, |
| abi: abi, |
| } |
| } |
| |
| fn build_struct<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::Struct { |
| let t = tcx.lookup_item_type(did); |
| let predicates = tcx.lookup_predicates(did); |
| let variant = tcx.lookup_adt_def(did).struct_variant(); |
| |
| clean::Struct { |
| struct_type: match &variant.fields[..] { |
| &[] => doctree::Unit, |
| &[_] if variant.kind == ty::VariantKind::Tuple => doctree::Newtype, |
| &[..] if variant.kind == ty::VariantKind::Tuple => doctree::Tuple, |
| _ => doctree::Plain, |
| }, |
| generics: (&t.generics, &predicates, subst::TypeSpace).clean(cx), |
| fields: variant.fields.clean(cx), |
| fields_stripped: false, |
| } |
| } |
| |
| fn build_type<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::ItemEnum { |
| let t = tcx.lookup_item_type(did); |
| let predicates = tcx.lookup_predicates(did); |
| match t.ty.sty { |
| ty::TyEnum(edef, _) if !tcx.sess.cstore.is_typedef(did) => { |
| return clean::EnumItem(clean::Enum { |
| generics: (&t.generics, &predicates, subst::TypeSpace).clean(cx), |
| variants_stripped: false, |
| variants: edef.variants.clean(cx), |
| }) |
| } |
| _ => {} |
| } |
| |
| clean::TypedefItem(clean::Typedef { |
| type_: t.ty.clean(cx), |
| generics: (&t.generics, &predicates, subst::TypeSpace).clean(cx), |
| }, false) |
| } |
| |
| pub fn build_impls<'a, 'tcx>(cx: &DocContext, |
| tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> Vec<clean::Item> { |
| tcx.populate_inherent_implementations_for_type_if_necessary(did); |
| let mut impls = Vec::new(); |
| |
| if let Some(i) = tcx.inherent_impls.borrow().get(&did) { |
| for &did in i.iter() { |
| build_impl(cx, tcx, did, &mut impls); |
| } |
| } |
| |
| // If this is the first time we've inlined something from this crate, then |
| // we inline *all* impls from the crate into this crate. Note that there's |
| // currently no way for us to filter this based on type, and we likely need |
| // many impls for a variety of reasons. |
| // |
| // Primarily, the impls will be used to populate the documentation for this |
| // type being inlined, but impls can also be used when generating |
| // documentation for primitives (no way to find those specifically). |
| if cx.populated_crate_impls.borrow_mut().insert(did.krate) { |
| for item in tcx.sess.cstore.crate_top_level_items(did.krate) { |
| populate_impls(cx, tcx, item.def, &mut impls); |
| } |
| |
| fn populate_impls<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| def: cstore::DefLike, |
| impls: &mut Vec<clean::Item>) { |
| match def { |
| cstore::DlImpl(did) => build_impl(cx, tcx, did, impls), |
| cstore::DlDef(Def::Mod(did)) => { |
| for item in tcx.sess.cstore.item_children(did) { |
| populate_impls(cx, tcx, item.def, impls) |
| } |
| } |
| _ => {} |
| } |
| } |
| } |
| |
| impls |
| } |
| |
| pub fn build_impl<'a, 'tcx>(cx: &DocContext, |
| tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId, |
| ret: &mut Vec<clean::Item>) { |
| if !cx.renderinfo.borrow_mut().inlined.insert(did) { |
| return |
| } |
| |
| let attrs = load_attrs(cx, tcx, did); |
| let associated_trait = tcx.impl_trait_ref(did); |
| |
| // Only inline impl if the implemented trait is |
| // reachable in rustdoc generated documentation |
| if let Some(traitref) = associated_trait { |
| if !cx.access_levels.borrow().is_doc_reachable(traitref.def_id) { |
| return |
| } |
| } |
| |
| // If this is a defaulted impl, then bail out early here |
| if tcx.sess.cstore.is_default_impl(did) { |
| return ret.push(clean::Item { |
| inner: clean::DefaultImplItem(clean::DefaultImpl { |
| // FIXME: this should be decoded |
| unsafety: hir::Unsafety::Normal, |
| trait_: match associated_trait.as_ref().unwrap().clean(cx) { |
| clean::TraitBound(polyt, _) => polyt.trait_, |
| clean::RegionBound(..) => unreachable!(), |
| }, |
| }), |
| source: clean::Span::empty(), |
| name: None, |
| attrs: attrs, |
| visibility: Some(clean::Inherited), |
| stability: tcx.lookup_stability(did).clean(cx), |
| deprecation: tcx.lookup_deprecation(did).clean(cx), |
| def_id: did, |
| }); |
| } |
| |
| let ty = tcx.lookup_item_type(did); |
| let for_ = ty.ty.clean(cx); |
| |
| // Only inline impl if the implementing type is |
| // reachable in rustdoc generated documentation |
| if let Some(did) = for_.def_id() { |
| if !cx.access_levels.borrow().is_doc_reachable(did) { |
| return |
| } |
| } |
| |
| let predicates = tcx.lookup_predicates(did); |
| let trait_items = tcx.sess.cstore.impl_items(did) |
| .iter() |
| .filter_map(|did| { |
| let did = did.def_id(); |
| let impl_item = tcx.impl_or_trait_item(did); |
| match impl_item { |
| ty::ConstTraitItem(ref assoc_const) => { |
| let did = assoc_const.def_id; |
| let type_scheme = tcx.lookup_item_type(did); |
| let default = if assoc_const.has_value { |
| Some(pprust::expr_to_string( |
| lookup_const_by_id(tcx, did, None).unwrap().0)) |
| } else { |
| None |
| }; |
| Some(clean::Item { |
| name: Some(assoc_const.name.clean(cx)), |
| inner: clean::AssociatedConstItem( |
| type_scheme.ty.clean(cx), |
| default, |
| ), |
| source: clean::Span::empty(), |
| attrs: vec![], |
| visibility: None, |
| stability: tcx.lookup_stability(did).clean(cx), |
| deprecation: tcx.lookup_deprecation(did).clean(cx), |
| def_id: did |
| }) |
| } |
| ty::MethodTraitItem(method) => { |
| if method.vis != ty::Visibility::Public && associated_trait.is_none() { |
| return None |
| } |
| let mut item = method.clean(cx); |
| item.inner = match item.inner.clone() { |
| clean::TyMethodItem(clean::TyMethod { |
| unsafety, decl, generics, abi |
| }) => { |
| let constness = if tcx.sess.cstore.is_const_fn(did) { |
| hir::Constness::Const |
| } else { |
| hir::Constness::NotConst |
| }; |
| |
| clean::MethodItem(clean::Method { |
| unsafety: unsafety, |
| constness: constness, |
| decl: decl, |
| generics: generics, |
| abi: abi |
| }) |
| } |
| _ => panic!("not a tymethod"), |
| }; |
| Some(item) |
| } |
| ty::TypeTraitItem(ref assoc_ty) => { |
| let did = assoc_ty.def_id; |
| let type_scheme = ty::TypeScheme { |
| ty: assoc_ty.ty.unwrap(), |
| generics: ty::Generics::empty() |
| }; |
| // Not sure the choice of ParamSpace actually matters here, |
| // because an associated type won't have generics on the LHS |
| let typedef = (type_scheme, ty::GenericPredicates::empty(), |
| subst::ParamSpace::TypeSpace).clean(cx); |
| Some(clean::Item { |
| name: Some(assoc_ty.name.clean(cx)), |
| inner: clean::TypedefItem(typedef, true), |
| source: clean::Span::empty(), |
| attrs: vec![], |
| visibility: None, |
| stability: tcx.lookup_stability(did).clean(cx), |
| deprecation: tcx.lookup_deprecation(did).clean(cx), |
| def_id: did |
| }) |
| } |
| } |
| }).collect::<Vec<_>>(); |
| let polarity = tcx.trait_impl_polarity(did); |
| let trait_ = associated_trait.clean(cx).map(|bound| { |
| match bound { |
| clean::TraitBound(polyt, _) => polyt.trait_, |
| clean::RegionBound(..) => unreachable!(), |
| } |
| }); |
| if trait_.def_id() == cx.deref_trait_did.get() { |
| super::build_deref_target_impls(cx, &trait_items, ret); |
| } |
| |
| let provided = trait_.def_id().map(|did| { |
| cx.tcx().provided_trait_methods(did) |
| .into_iter() |
| .map(|meth| meth.name.to_string()) |
| .collect() |
| }).unwrap_or(HashSet::new()); |
| |
| ret.push(clean::Item { |
| inner: clean::ImplItem(clean::Impl { |
| unsafety: hir::Unsafety::Normal, // FIXME: this should be decoded |
| provided_trait_methods: provided, |
| trait_: trait_, |
| for_: for_, |
| generics: (&ty.generics, &predicates, subst::TypeSpace).clean(cx), |
| items: trait_items, |
| polarity: polarity.map(|p| { p.clean(cx) }), |
| }), |
| source: clean::Span::empty(), |
| name: None, |
| attrs: attrs, |
| visibility: Some(clean::Inherited), |
| stability: tcx.lookup_stability(did).clean(cx), |
| deprecation: tcx.lookup_deprecation(did).clean(cx), |
| def_id: did, |
| }); |
| } |
| |
| fn build_module<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::Module { |
| let mut items = Vec::new(); |
| fill_in(cx, tcx, did, &mut items); |
| return clean::Module { |
| items: items, |
| is_crate: false, |
| }; |
| |
| fn fill_in<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId, items: &mut Vec<clean::Item>) { |
| // If we're reexporting a reexport it may actually reexport something in |
| // two namespaces, so the target may be listed twice. Make sure we only |
| // visit each node at most once. |
| let mut visited = HashSet::new(); |
| for item in tcx.sess.cstore.item_children(did) { |
| match item.def { |
| cstore::DlDef(Def::ForeignMod(did)) => { |
| fill_in(cx, tcx, did, items); |
| } |
| cstore::DlDef(def) if item.vis == ty::Visibility::Public => { |
| if !visited.insert(def) { continue } |
| if let Some(i) = try_inline_def(cx, tcx, def) { |
| items.extend(i) |
| } |
| } |
| cstore::DlDef(..) => {} |
| // All impls were inlined above |
| cstore::DlImpl(..) => {} |
| cstore::DlField => panic!("unimplemented field"), |
| } |
| } |
| } |
| } |
| |
| fn build_const<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId) -> clean::Constant { |
| let (expr, ty) = lookup_const_by_id(tcx, did, None).unwrap_or_else(|| { |
| panic!("expected lookup_const_by_id to succeed for {:?}", did); |
| }); |
| debug!("converting constant expr {:?} to snippet", expr); |
| let sn = pprust::expr_to_string(expr); |
| debug!("got snippet {}", sn); |
| |
| clean::Constant { |
| type_: ty.map(|t| t.clean(cx)).unwrap_or_else(|| tcx.lookup_item_type(did).ty.clean(cx)), |
| expr: sn |
| } |
| } |
| |
| fn build_static<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| did: DefId, |
| mutable: bool) -> clean::Static { |
| clean::Static { |
| type_: tcx.lookup_item_type(did).ty.clean(cx), |
| mutability: if mutable {clean::Mutable} else {clean::Immutable}, |
| expr: "\n\n\n".to_string(), // trigger the "[definition]" links |
| } |
| } |
| |
| /// A trait's generics clause actually contains all of the predicates for all of |
| /// its associated types as well. We specifically move these clauses to the |
| /// associated types instead when displaying, so when we're genering the |
| /// generics for the trait itself we need to be sure to remove them. |
| /// |
| /// The inverse of this filtering logic can be found in the `Clean` |
| /// implementation for `AssociatedType` |
| fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) |
| -> clean::Generics { |
| g.where_predicates.retain(|pred| { |
| match *pred { |
| clean::WherePredicate::BoundPredicate { |
| ty: clean::QPath { |
| self_type: box clean::Generic(ref s), |
| trait_: box clean::ResolvedPath { did, .. }, |
| name: ref _name, |
| }, .. |
| } => *s != "Self" || did != trait_did, |
| _ => true, |
| } |
| }); |
| return g; |
| } |
| |
| /// Supertrait bounds for a trait are also listed in the generics coming from |
| /// the metadata for a crate, so we want to separate those out and create a new |
| /// list of explicit supertrait bounds to render nicely. |
| fn separate_supertrait_bounds(mut g: clean::Generics) |
| -> (clean::Generics, Vec<clean::TyParamBound>) { |
| let mut ty_bounds = Vec::new(); |
| g.where_predicates.retain(|pred| { |
| match *pred { |
| clean::WherePredicate::BoundPredicate { |
| ty: clean::Generic(ref s), |
| ref bounds |
| } if *s == "Self" => { |
| ty_bounds.extend(bounds.iter().cloned()); |
| false |
| } |
| _ => true, |
| } |
| }); |
| (g, ty_bounds) |
| } |
