1 use crate::clean::auto_trait::AutoTraitFinder;
2 use crate::clean::blanket_impl::BlanketImplFinder;
4 inline, Clean, Crate, Generic, GenericArg, GenericArgs, ImportSource, Item, ItemKind, Lifetime,
5 Path, PathSegment, PolyTrait, Primitive, PrimitiveType, ResolvedPath, Type, TypeBinding,
7 use crate::core::DocContext;
8 use crate::formats::item_type::ItemType;
10 use rustc_ast::tokenstream::TokenTree;
12 use rustc_hir::def::{DefKind, Res};
13 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
14 use rustc_middle::mir::interpret::ConstValue;
15 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
16 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
17 use rustc_span::symbol::{kw, sym, Symbol};
18 use std::fmt::Write as _;
24 crate fn krate(cx: &mut DocContext<'_>) -> Crate {
25 use crate::visit_lib::LibEmbargoVisitor;
27 let krate = cx.tcx.hir().krate();
28 let module = crate::visit_ast::RustdocVisitor::new(cx).visit(krate);
30 cx.cache.deref_trait_did = cx.tcx.lang_items().deref_trait();
31 cx.cache.deref_mut_trait_did = cx.tcx.lang_items().deref_mut_trait();
32 cx.cache.owned_box_did = cx.tcx.lang_items().owned_box();
34 let mut externs = Vec::new();
35 for &cnum in cx.tcx.crates(()).iter() {
36 externs.push((cnum, cnum.clean(cx)));
37 // Analyze doc-reachability for extern items
38 LibEmbargoVisitor::new(cx).visit_lib(cnum);
40 externs.sort_by(|&(a, _), &(b, _)| a.cmp(&b));
42 // Clean the crate, translating the entire librustc_ast AST to one that is
43 // understood by rustdoc.
44 let mut module = module.clean(cx);
47 ItemKind::ModuleItem(ref module) => {
48 for it in &module.items {
49 // `compiler_builtins` should be masked too, but we can't apply
50 // `#[doc(masked)]` to the injected `extern crate` because it's unstable.
51 if it.is_extern_crate()
52 && (it.attrs.has_doc_flag(sym::masked)
53 || cx.tcx.is_compiler_builtins(it.def_id.krate()))
55 cx.cache.masked_crates.insert(it.def_id.krate());
62 let local_crate = LOCAL_CRATE.clean(cx);
63 let src = local_crate.src(cx.tcx);
64 let name = local_crate.name(cx.tcx);
65 let primitives = local_crate.primitives(cx.tcx);
66 let keywords = local_crate.keywords(cx.tcx);
68 let m = match *module.kind {
69 ItemKind::ModuleItem(ref mut m) => m,
72 m.items.extend(primitives.iter().map(|&(def_id, prim)| {
73 Item::from_def_id_and_parts(
76 ItemKind::PrimitiveItem(prim),
80 m.items.extend(keywords.into_iter().map(|(def_id, kw)| {
81 Item::from_def_id_and_parts(def_id, Some(kw), ItemKind::KeywordItem(kw), cx)
91 external_traits: cx.external_traits.clone(),
96 fn external_generic_args(
97 cx: &mut DocContext<'_>,
98 trait_did: Option<DefId>,
100 bindings: Vec<TypeBinding>,
101 substs: SubstsRef<'_>,
103 let mut skip_self = has_self;
104 let mut ty_kind = None;
105 let args: Vec<_> = substs
107 .filter_map(|kind| match kind.unpack() {
108 GenericArgKind::Lifetime(lt) => match lt {
109 ty::ReLateBound(_, ty::BoundRegion { kind: ty::BrAnon(_), .. }) => {
110 Some(GenericArg::Lifetime(Lifetime::elided()))
112 _ => lt.clean(cx).map(GenericArg::Lifetime),
114 GenericArgKind::Type(_) if skip_self => {
118 GenericArgKind::Type(ty) => {
119 ty_kind = Some(ty.kind());
120 Some(GenericArg::Type(ty.clean(cx)))
122 GenericArgKind::Const(ct) => Some(GenericArg::Const(ct.clean(cx))),
127 // Attempt to sugar an external path like Fn<(A, B,), C> to Fn(A, B) -> C
128 Some(did) if cx.tcx.fn_trait_kind_from_lang_item(did).is_some() => {
129 assert!(ty_kind.is_some());
130 let inputs = match ty_kind {
131 Some(ty::Tuple(ref tys)) => tys.iter().map(|t| t.expect_ty().clean(cx)).collect(),
132 _ => return GenericArgs::AngleBracketed { args, bindings },
135 // FIXME(#20299) return type comes from a projection now
136 // match types[1].kind {
137 // ty::Tuple(ref v) if v.is_empty() => None, // -> ()
138 // _ => Some(types[1].clean(cx))
140 GenericArgs::Parenthesized { inputs, output }
142 _ => GenericArgs::AngleBracketed { args, bindings },
146 // trait_did should be set to a trait's DefId if called on a TraitRef, in order to sugar
147 // from Fn<(A, B,), C> to Fn(A, B) -> C
148 pub(super) fn external_path(
149 cx: &mut DocContext<'_>,
151 trait_did: Option<DefId>,
153 bindings: Vec<TypeBinding>,
154 substs: SubstsRef<'_>,
159 segments: vec![PathSegment {
161 args: external_generic_args(cx, trait_did, has_self, bindings, substs),
166 crate fn strip_type(ty: Type) -> Type {
168 Type::ResolvedPath { path, did, is_generic } => {
169 Type::ResolvedPath { path: strip_path(&path), did, is_generic }
171 Type::DynTrait(mut bounds, lt) => {
172 let first = bounds.remove(0);
173 let stripped_trait = strip_type(first.trait_);
177 PolyTrait { trait_: stripped_trait, generic_params: first.generic_params },
179 Type::DynTrait(bounds, lt)
181 Type::Tuple(inner_tys) => {
182 Type::Tuple(inner_tys.iter().map(|t| strip_type(t.clone())).collect())
184 Type::Slice(inner_ty) => Type::Slice(Box::new(strip_type(*inner_ty))),
185 Type::Array(inner_ty, s) => Type::Array(Box::new(strip_type(*inner_ty)), s),
186 Type::RawPointer(m, inner_ty) => Type::RawPointer(m, Box::new(strip_type(*inner_ty))),
187 Type::BorrowedRef { lifetime, mutability, type_ } => {
188 Type::BorrowedRef { lifetime, mutability, type_: Box::new(strip_type(*type_)) }
190 Type::QPath { name, self_type, trait_, self_def_id } => Type::QPath {
193 self_type: Box::new(strip_type(*self_type)),
194 trait_: Box::new(strip_type(*trait_)),
200 crate fn strip_path(path: &Path) -> Path {
204 .map(|s| PathSegment {
206 args: GenericArgs::AngleBracketed { args: vec![], bindings: vec![] },
210 Path { global: path.global, res: path.res, segments }
213 crate fn qpath_to_string(p: &hir::QPath<'_>) -> String {
214 let segments = match *p {
215 hir::QPath::Resolved(_, ref path) => &path.segments,
216 hir::QPath::TypeRelative(_, ref segment) => return segment.ident.to_string(),
217 hir::QPath::LangItem(lang_item, ..) => return lang_item.name().to_string(),
220 let mut s = String::new();
221 for (i, seg) in segments.iter().enumerate() {
225 if seg.ident.name != kw::PathRoot {
226 s.push_str(&seg.ident.as_str());
232 crate fn build_deref_target_impls(cx: &mut DocContext<'_>, items: &[Item], ret: &mut Vec<Item>) {
236 let target = match *item.kind {
237 ItemKind::TypedefItem(ref t, true) => &t.type_,
241 if let Some(prim) = target.primitive_type() {
242 for &did in prim.impls(tcx).iter().filter(|did| !did.is_local()) {
243 inline::build_impl(cx, None, did, None, ret);
245 } else if let ResolvedPath { did, .. } = *target {
247 inline::build_impls(cx, None, did, None, ret);
253 crate fn name_from_pat(p: &hir::Pat<'_>) -> Symbol {
255 debug!("trying to get a name from pattern: {:?}", p);
257 Symbol::intern(&match p.kind {
258 PatKind::Wild | PatKind::Struct(..) => return kw::Underscore,
259 PatKind::Binding(_, _, ident, _) => return ident.name,
260 PatKind::TupleStruct(ref p, ..) | PatKind::Path(ref p) => qpath_to_string(p),
261 PatKind::Or(ref pats) => pats
263 .map(|p| name_from_pat(&**p).to_string())
264 .collect::<Vec<String>>()
266 PatKind::Tuple(ref elts, _) => format!(
269 .map(|p| name_from_pat(&**p).to_string())
270 .collect::<Vec<String>>()
273 PatKind::Box(ref p) => return name_from_pat(&**p),
274 PatKind::Ref(ref p, _) => return name_from_pat(&**p),
275 PatKind::Lit(..) => {
277 "tried to get argument name from PatKind::Lit, which is silly in function arguments"
279 return Symbol::intern("()");
281 PatKind::Range(..) => return kw::Underscore,
282 PatKind::Slice(ref begin, ref mid, ref end) => {
283 let begin = begin.iter().map(|p| name_from_pat(&**p).to_string());
284 let mid = mid.as_ref().map(|p| format!("..{}", name_from_pat(&**p))).into_iter();
285 let end = end.iter().map(|p| name_from_pat(&**p).to_string());
286 format!("[{}]", begin.chain(mid).chain(end).collect::<Vec<_>>().join(", "))
291 crate fn print_const(cx: &DocContext<'_>, n: &'tcx ty::Const<'_>) -> String {
293 ty::ConstKind::Unevaluated(ty::Unevaluated { def, substs: _, promoted }) => {
294 let mut s = if let Some(def) = def.as_local() {
295 let hir_id = cx.tcx.hir().local_def_id_to_hir_id(def.did);
296 print_const_expr(cx.tcx, cx.tcx.hir().body_owned_by(hir_id))
298 inline::print_inlined_const(cx.tcx, def.did)
300 if let Some(promoted) = promoted {
301 s.push_str(&format!("::{:?}", promoted))
306 let mut s = n.to_string();
307 // array lengths are obviously usize
308 if s.ends_with("_usize") {
309 let n = s.len() - "_usize".len();
311 if s.ends_with(": ") {
312 let n = s.len() - ": ".len();
321 crate fn print_evaluated_const(tcx: TyCtxt<'_>, def_id: DefId) -> Option<String> {
322 tcx.const_eval_poly(def_id).ok().and_then(|val| {
323 let ty = tcx.type_of(def_id);
324 match (val, ty.kind()) {
325 (_, &ty::Ref(..)) => None,
326 (ConstValue::Scalar(_), &ty::Adt(_, _)) => None,
327 (ConstValue::Scalar(_), _) => {
328 let const_ = ty::Const::from_value(tcx, val, ty);
329 Some(print_const_with_custom_print_scalar(tcx, const_))
336 fn format_integer_with_underscore_sep(num: &str) -> String {
337 let num_chars: Vec<_> = num.chars().collect();
338 let mut num_start_index = if num_chars.get(0) == Some(&'-') { 1 } else { 0 };
339 let chunk_size = match num[num_start_index..].as_bytes() {
340 [b'0', b'b' | b'x', ..] => {
341 num_start_index += 2;
344 [b'0', b'o', ..] => {
345 num_start_index += 2;
346 let remaining_chars = num_chars.len() - num_start_index;
347 if remaining_chars <= 6 {
348 // don't add underscores to Unix permissions like 0755 or 100755
349 return num.to_string();
356 num_chars[..num_start_index]
358 .chain(num_chars[num_start_index..].rchunks(chunk_size).rev().intersperse(&['_']).flatten())
362 fn print_const_with_custom_print_scalar(tcx: TyCtxt<'_>, ct: &'tcx ty::Const<'tcx>) -> String {
363 // Use a slightly different format for integer types which always shows the actual value.
364 // For all other types, fallback to the original `pretty_print_const`.
365 match (ct.val, ct.ty.kind()) {
366 (ty::ConstKind::Value(ConstValue::Scalar(int)), ty::Uint(ui)) => {
367 format!("{}{}", format_integer_with_underscore_sep(&int.to_string()), ui.name_str())
369 (ty::ConstKind::Value(ConstValue::Scalar(int)), ty::Int(i)) => {
370 let ty = tcx.lift(ct.ty).unwrap();
371 let size = tcx.layout_of(ty::ParamEnv::empty().and(ty)).unwrap().size;
372 let data = int.assert_bits(size);
373 let sign_extended_data = size.sign_extend(data) as i128;
377 format_integer_with_underscore_sep(&sign_extended_data.to_string()),
385 crate fn is_literal_expr(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
386 if let hir::Node::Expr(expr) = tcx.hir().get(hir_id) {
387 if let hir::ExprKind::Lit(_) = &expr.kind {
391 if let hir::ExprKind::Unary(hir::UnOp::Neg, expr) = &expr.kind {
392 if let hir::ExprKind::Lit(_) = &expr.kind {
401 crate fn print_const_expr(tcx: TyCtxt<'_>, body: hir::BodyId) -> String {
403 let value = &hir.body(body).value;
405 let snippet = if !value.span.from_expansion() {
406 tcx.sess.source_map().span_to_snippet(value.span).ok()
411 snippet.unwrap_or_else(|| rustc_hir_pretty::id_to_string(&hir, body.hir_id))
414 /// Given a type Path, resolve it to a Type using the TyCtxt
415 crate fn resolve_type(cx: &mut DocContext<'_>, path: Path, id: hir::HirId) -> Type {
416 debug!("resolve_type({:?},{:?})", path, id);
418 let is_generic = match path.res {
419 Res::PrimTy(p) => return Primitive(PrimitiveType::from(p)),
420 Res::SelfTy(..) if path.segments.len() == 1 => {
421 return Generic(kw::SelfUpper);
423 Res::Def(DefKind::TyParam, _) if path.segments.len() == 1 => {
424 return Generic(Symbol::intern(&path.whole_name()));
426 Res::SelfTy(..) | Res::Def(DefKind::TyParam | DefKind::AssocTy, _) => true,
429 let did = register_res(cx, path.res);
430 ResolvedPath { path, did, is_generic }
433 crate fn get_auto_trait_and_blanket_impls(
434 cx: &mut DocContext<'tcx>,
436 ) -> impl Iterator<Item = Item> {
440 .generic_activity("get_auto_trait_impls")
441 .run(|| AutoTraitFinder::new(cx).get_auto_trait_impls(item_def_id));
442 let blanket_impls = cx
445 .generic_activity("get_blanket_impls")
446 .run(|| BlanketImplFinder { cx }.get_blanket_impls(item_def_id));
447 auto_impls.into_iter().chain(blanket_impls)
450 /// If `res` has a documentation page associated, store it in the cache.
452 /// This is later used by [`href()`] to determine the HTML link for the item.
454 /// [`href()`]: crate::html::format::href
455 crate fn register_res(cx: &mut DocContext<'_>, res: Res) -> DefId {
457 debug!("register_res({:?})", res);
459 let (did, kind) = match res {
460 Res::Def(DefKind::AssocTy | DefKind::AssocFn | DefKind::AssocConst, i) => {
461 // associated items are documented, but on the page of their parent
462 (cx.tcx.parent(i).unwrap(), ItemType::Trait)
464 Res::Def(DefKind::Variant, i) => {
465 // variant items are documented, but on the page of their parent
466 (cx.tcx.parent(i).expect("cannot get parent def id"), ItemType::Enum)
468 // Each of these have their own page.
472 (Fn | TyAlias | Enum | Trait | Struct | Union | Mod | ForeignTy | Const | Static
473 | Macro(..) | TraitAlias),
475 ) => (i, kind.into()),
476 // This is part of a trait definition; document the trait.
477 Res::SelfTy(Some(trait_def_id), _) => (trait_def_id, ItemType::Trait),
478 // This is an inherent impl; it doesn't have its own page.
479 Res::SelfTy(None, Some((impl_def_id, _))) => return impl_def_id,
480 Res::SelfTy(None, None)
485 | Res::NonMacroAttr(_)
486 | Res::Err => return res.def_id(),
488 TyParam | ConstParam | Ctor(..) | ExternCrate | Use | ForeignMod | AnonConst | OpaqueTy
489 | Field | LifetimeParam | GlobalAsm | Impl | Closure | Generator,
496 inline::record_extern_fqn(cx, did, kind);
497 if let ItemType::Trait = kind {
498 inline::record_extern_trait(cx, did);
503 crate fn resolve_use_source(cx: &mut DocContext<'_>, path: Path) -> ImportSource {
505 did: if path.res.opt_def_id().is_none() { None } else { Some(register_res(cx, path.res)) },
510 crate fn enter_impl_trait<F, R>(cx: &mut DocContext<'_>, f: F) -> R
512 F: FnOnce(&mut DocContext<'_>) -> R,
514 let old_bounds = mem::take(&mut cx.impl_trait_bounds);
516 assert!(cx.impl_trait_bounds.is_empty());
517 cx.impl_trait_bounds = old_bounds;
521 /// Find the nearest parent module of a [`DefId`].
522 crate fn find_nearest_parent_module(tcx: TyCtxt<'_>, def_id: DefId) -> Option<DefId> {
523 if def_id.is_top_level_module() {
524 // The crate root has no parent. Use it as the root instead.
527 let mut current = def_id;
528 // The immediate parent might not always be a module.
529 // Find the first parent which is.
530 while let Some(parent) = tcx.parent(current) {
531 if tcx.def_kind(parent) == DefKind::Mod {
540 /// Checks for the existence of `hidden` in the attribute below if `flag` is `sym::hidden`:
547 /// This function exists because it runs on `hir::Attributes` whereas the other is a
548 /// `clean::Attributes` method.
549 crate fn has_doc_flag(attrs: ty::Attributes<'_>, flag: Symbol) -> bool {
550 attrs.iter().any(|attr| {
551 attr.has_name(sym::doc)
552 && attr.meta_item_list().map_or(false, |l| rustc_attr::list_contains_name(&l, flag))
556 /// A link to `doc.rust-lang.org` that includes the channel name. Use this instead of manual links
557 /// so that the channel is consistent.
559 /// Set by `bootstrap::Builder::doc_rust_lang_org_channel` in order to keep tests passing on beta/stable.
560 crate const DOC_RUST_LANG_ORG_CHANNEL: &'static str = env!("DOC_RUST_LANG_ORG_CHANNEL");
562 /// Render a sequence of macro arms in a format suitable for displaying to the user
563 /// as part of an item declaration.
564 pub(super) fn render_macro_arms<'a>(
565 matchers: impl Iterator<Item = &'a TokenTree>,
568 let mut out = String::new();
569 for matcher in matchers {
570 writeln!(out, " {} => {{ ... }}{}", render_macro_matcher(matcher), arm_delim).unwrap();
575 /// Render a macro matcher in a format suitable for displaying to the user
576 /// as part of an item declaration.
577 pub(super) fn render_macro_matcher(matcher: &TokenTree) -> String {
578 rustc_ast_pretty::pprust::tt_to_string(matcher)