1 //! This module implements [RFC 1946]: Intra-rustdoc-links
3 //! [RFC 1946]: https://github.com/rust-lang/rfcs/blob/master/text/1946-intra-rustdoc-links.md
5 use pulldown_cmark::LinkType;
6 use rustc_ast::util::comments::may_have_doc_links;
7 use rustc_data_structures::{fx::FxHashMap, intern::Interned, stable_set::FxHashSet};
8 use rustc_errors::{Applicability, Diagnostic};
9 use rustc_hir::def::Namespace::*;
10 use rustc_hir::def::{DefKind, Namespace, PerNS};
11 use rustc_hir::def_id::{DefId, CRATE_DEF_ID};
12 use rustc_hir::Mutability;
13 use rustc_middle::ty::{DefIdTree, Ty, TyCtxt};
14 use rustc_middle::{bug, span_bug, ty};
15 use rustc_resolve::ParentScope;
16 use rustc_session::lint::Lint;
17 use rustc_span::hygiene::MacroKind;
18 use rustc_span::symbol::{sym, Ident, Symbol};
19 use rustc_span::{BytePos, DUMMY_SP};
20 use smallvec::{smallvec, SmallVec};
27 use crate::clean::{self, utils::find_nearest_parent_module};
28 use crate::clean::{Crate, Item, ItemId, ItemLink, PrimitiveType};
29 use crate::core::DocContext;
30 use crate::html::markdown::{markdown_links, MarkdownLink};
31 use crate::lint::{BROKEN_INTRA_DOC_LINKS, PRIVATE_INTRA_DOC_LINKS};
32 use crate::passes::Pass;
33 use crate::visit::DocVisitor;
36 crate use early::early_resolve_intra_doc_links;
38 crate const COLLECT_INTRA_DOC_LINKS: Pass = Pass {
39 name: "collect-intra-doc-links",
40 run: collect_intra_doc_links,
41 description: "resolves intra-doc links",
44 fn collect_intra_doc_links(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
46 LinkCollector { cx, mod_ids: Vec::new(), visited_links: FxHashMap::default() };
47 collector.visit_crate(&krate);
51 /// Top-level errors emitted by this pass.
53 Resolve(Box<ResolutionFailure<'a>>),
54 AnchorFailure(AnchorFailure),
57 impl<'a> From<ResolutionFailure<'a>> for ErrorKind<'a> {
58 fn from(err: ResolutionFailure<'a>) -> Self {
59 ErrorKind::Resolve(box err)
63 #[derive(Copy, Clone, Debug, Hash)]
66 Primitive(PrimitiveType),
69 type ResolveRes = rustc_hir::def::Res<rustc_ast::NodeId>;
72 fn descr(self) -> &'static str {
74 Res::Def(kind, id) => ResolveRes::Def(kind, id).descr(),
75 Res::Primitive(_) => "builtin type",
79 fn article(self) -> &'static str {
81 Res::Def(kind, id) => ResolveRes::Def(kind, id).article(),
82 Res::Primitive(_) => "a",
86 fn name(self, tcx: TyCtxt<'_>) -> Symbol {
88 Res::Def(_, id) => tcx.item_name(id),
89 Res::Primitive(prim) => prim.as_sym(),
93 fn def_id(self, tcx: TyCtxt<'_>) -> DefId {
95 Res::Def(_, id) => id,
96 Res::Primitive(prim) => *PrimitiveType::primitive_locations(tcx).get(&prim).unwrap(),
100 fn as_hir_res(self) -> Option<rustc_hir::def::Res> {
102 Res::Def(kind, id) => Some(rustc_hir::def::Res::Def(kind, id)),
103 // FIXME: maybe this should handle the subset of PrimitiveType that fits into hir::PrimTy?
104 Res::Primitive(_) => None,
108 /// Used for error reporting.
109 fn disambiguator_suggestion(self) -> Suggestion {
110 let kind = match self {
111 Res::Primitive(_) => return Suggestion::Prefix("prim"),
112 Res::Def(kind, _) => kind,
114 if kind == DefKind::Macro(MacroKind::Bang) {
115 return Suggestion::Macro;
116 } else if kind == DefKind::Fn || kind == DefKind::AssocFn {
117 return Suggestion::Function;
118 } else if kind == DefKind::Field {
119 return Suggestion::RemoveDisambiguator;
122 let prefix = match kind {
123 DefKind::Struct => "struct",
124 DefKind::Enum => "enum",
125 DefKind::Trait => "trait",
126 DefKind::Union => "union",
127 DefKind::Mod => "mod",
128 DefKind::Const | DefKind::ConstParam | DefKind::AssocConst | DefKind::AnonConst => {
131 DefKind::Static(_) => "static",
132 DefKind::Macro(MacroKind::Derive) => "derive",
133 // Now handle things that don't have a specific disambiguator
136 .expect("tried to calculate a disambiguator for a def without a namespace?")
138 Namespace::TypeNS => "type",
139 Namespace::ValueNS => "value",
140 Namespace::MacroNS => "macro",
144 Suggestion::Prefix(prefix)
148 impl TryFrom<ResolveRes> for Res {
151 fn try_from(res: ResolveRes) -> Result<Self, ()> {
152 use rustc_hir::def::Res::*;
154 Def(kind, id) => Ok(Res::Def(kind, id)),
155 PrimTy(prim) => Ok(Res::Primitive(PrimitiveType::from_hir(prim))),
157 NonMacroAttr(..) | Err => Result::Err(()),
158 other => bug!("unrecognized res {:?}", other),
163 /// A link failed to resolve.
164 #[derive(Clone, Debug)]
165 enum ResolutionFailure<'a> {
166 /// This resolved, but with the wrong namespace.
168 /// What the link resolved to.
170 /// The expected namespace for the resolution, determined from the link's disambiguator.
172 /// E.g., for `[fn@Result]` this is [`Namespace::ValueNS`],
173 /// even though `Result`'s actual namespace is [`Namespace::TypeNS`].
174 expected_ns: Namespace,
176 /// The link failed to resolve. [`resolution_failure`] should look to see if there's
177 /// a more helpful error that can be given.
179 /// Item on which the link is resolved, used for resolving `Self`.
181 /// The scope the link was resolved in.
183 /// If part of the link resolved, this has the `Res`.
185 /// In `[std::io::Error::x]`, `std::io::Error` would be a partial resolution.
186 partial_res: Option<Res>,
187 /// The remaining unresolved path segments.
189 /// In `[std::io::Error::x]`, `x` would be unresolved.
190 unresolved: Cow<'a, str>,
192 /// This happens when rustdoc can't determine the parent scope for an item.
193 /// It is always a bug in rustdoc.
195 /// This link has malformed generic parameters; e.g., the angle brackets are unbalanced.
196 MalformedGenerics(MalformedGenerics),
197 /// Used to communicate that this should be ignored, but shouldn't be reported to the user.
199 /// This happens when there is no disambiguator and one of the namespaces
200 /// failed to resolve.
204 #[derive(Clone, Debug)]
205 enum MalformedGenerics {
206 /// This link has unbalanced angle brackets.
208 /// For example, `Vec<T` should trigger this, as should `Vec<T>>`.
209 UnbalancedAngleBrackets,
210 /// The generics are not attached to a type.
212 /// For example, `<T>` should trigger this.
214 /// This is detected by checking if the path is empty after the generics are stripped.
216 /// The link uses fully-qualified syntax, which is currently unsupported.
218 /// For example, `<Vec as IntoIterator>::into_iter` should trigger this.
220 /// This is detected by checking if ` as ` (the keyword `as` with spaces around it) is inside
222 HasFullyQualifiedSyntax,
223 /// The link has an invalid path separator.
225 /// For example, `Vec:<T>:new()` should trigger this. Note that `Vec:new()` will **not**
226 /// trigger this because it has no generics and thus [`strip_generics_from_path`] will not be
229 /// Note that this will also **not** be triggered if the invalid path separator is inside angle
230 /// brackets because rustdoc mostly ignores what's inside angle brackets (except for
231 /// [`HasFullyQualifiedSyntax`](MalformedGenerics::HasFullyQualifiedSyntax)).
233 /// This is detected by checking if there is a colon followed by a non-colon in the link.
234 InvalidPathSeparator,
235 /// The link has too many angle brackets.
237 /// For example, `Vec<<T>>` should trigger this.
238 TooManyAngleBrackets,
239 /// The link has empty angle brackets.
241 /// For example, `Vec<>` should trigger this.
245 impl ResolutionFailure<'_> {
246 /// This resolved fully (not just partially) but is erroneous for some other reason
248 /// Returns the full resolution of the link, if present.
249 fn full_res(&self) -> Option<Res> {
251 Self::WrongNamespace { res, expected_ns: _ } => Some(*res),
257 #[derive(Clone, Copy)]
259 /// User error: `[std#x#y]` is not valid
261 /// The anchor provided by the user conflicts with Rustdoc's generated anchor.
263 /// This is an unfortunate state of affairs. Not every item that can be
264 /// linked to has its own page; sometimes it is a subheading within a page,
265 /// like for associated items. In those cases, rustdoc uses an anchor to
266 /// link to the subheading. Since you can't have two anchors for the same
267 /// link, Rustdoc disallows having a user-specified anchor.
269 /// Most of the time this is fine, because you can just link to the page of
270 /// the item if you want to provide your own anchor.
271 RustdocAnchorConflict(Res),
274 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
275 crate enum UrlFragment {
281 /// Render the fragment, including the leading `#`.
282 crate fn render(&self, s: &mut String, tcx: TyCtxt<'_>) -> std::fmt::Result {
284 UrlFragment::Item(frag) => frag.render(s, tcx),
285 UrlFragment::UserWritten(raw) => write!(s, "#{}", raw),
290 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
291 crate struct ItemFragment(FragmentKind, DefId);
293 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
294 crate enum FragmentKind {
306 /// Create a fragment for an associated item.
307 #[instrument(level = "debug")]
308 fn from_assoc_item(item: &ty::AssocItem) -> Self {
309 let def_id = item.def_id;
311 ty::AssocKind::Fn => {
312 if item.defaultness.has_value() {
313 ItemFragment(FragmentKind::Method, def_id)
315 ItemFragment(FragmentKind::TyMethod, def_id)
318 ty::AssocKind::Const => ItemFragment(FragmentKind::AssociatedConstant, def_id),
319 ty::AssocKind::Type => ItemFragment(FragmentKind::AssociatedType, def_id),
323 /// Render the fragment, including the leading `#`.
324 crate fn render(&self, s: &mut String, tcx: TyCtxt<'_>) -> std::fmt::Result {
327 ItemFragment(kind, def_id) => {
328 let name = tcx.item_name(def_id);
330 FragmentKind::Method => write!(s, "method.{}", name),
331 FragmentKind::TyMethod => write!(s, "tymethod.{}", name),
332 FragmentKind::AssociatedConstant => write!(s, "associatedconstant.{}", name),
333 FragmentKind::AssociatedType => write!(s, "associatedtype.{}", name),
334 FragmentKind::StructField => write!(s, "structfield.{}", name),
335 FragmentKind::Variant => write!(s, "variant.{}", name),
336 FragmentKind::VariantField => {
337 let variant = tcx.item_name(tcx.parent(def_id));
338 write!(s, "variant.{}.field.{}", variant, name)
346 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
347 struct ResolutionInfo {
350 dis: Option<Disambiguator>,
352 extra_fragment: Option<String>,
356 struct DiagnosticInfo<'a> {
360 link_range: Range<usize>,
363 #[derive(Clone, Debug, Hash)]
365 res: (Res, Option<UrlFragment>),
368 struct LinkCollector<'a, 'tcx> {
369 cx: &'a mut DocContext<'tcx>,
370 /// A stack of modules used to decide what scope to resolve in.
372 /// The last module will be used if the parent scope of the current item is
375 /// Cache the resolved links so we can avoid resolving (and emitting errors for) the same link.
376 /// The link will be `None` if it could not be resolved (i.e. the error was cached).
377 visited_links: FxHashMap<ResolutionInfo, Option<CachedLink>>,
380 impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
381 /// Given a full link, parse it as an [enum struct variant].
383 /// In particular, this will return an error whenever there aren't three
384 /// full path segments left in the link.
386 /// [enum struct variant]: rustc_hir::VariantData::Struct
387 fn variant_field<'path>(
389 path_str: &'path str,
392 ) -> Result<(Res, Option<ItemFragment>), ErrorKind<'path>> {
393 let tcx = self.cx.tcx;
394 let no_res = || ResolutionFailure::NotResolved {
398 unresolved: path_str.into(),
401 debug!("looking for enum variant {}", path_str);
402 let mut split = path_str.rsplitn(3, "::");
403 let variant_field_name = split
405 .map(|f| Symbol::intern(f))
406 .expect("fold_item should ensure link is non-empty");
408 // we're not sure this is a variant at all, so use the full string
409 // If there's no second component, the link looks like `[path]`.
410 // So there's no partial res and we should say the whole link failed to resolve.
411 split.next().map(|f| Symbol::intern(f)).ok_or_else(no_res)?;
414 .map(|f| f.to_owned())
415 // If there's no third component, we saw `[a::b]` before and it failed to resolve.
416 // So there's no partial res.
417 .ok_or_else(no_res)?;
418 let ty_res = self.resolve_path(&path, TypeNS, item_id, module_id).ok_or_else(no_res)?;
421 Res::Def(DefKind::Enum, did) => {
425 .flat_map(|imp| tcx.associated_items(*imp).in_definition_order())
426 .any(|item| item.name == variant_name)
428 // This is just to let `fold_item` know that this shouldn't be considered;
429 // it's a bug for the error to make it to the user
430 return Err(ResolutionFailure::Dummy.into());
432 match tcx.type_of(did).kind() {
433 ty::Adt(def, _) if def.is_enum() => {
434 if let Some(field) = def.all_fields().find(|f| f.name == variant_field_name)
436 Ok((ty_res, Some(ItemFragment(FragmentKind::VariantField, field.did))))
438 Err(ResolutionFailure::NotResolved {
441 partial_res: Some(Res::Def(DefKind::Enum, def.did())),
442 unresolved: variant_field_name.to_string().into(),
450 _ => Err(ResolutionFailure::NotResolved {
453 partial_res: Some(ty_res),
454 unresolved: variant_name.to_string().into(),
460 /// Given a primitive type, try to resolve an associated item.
461 fn resolve_primitive_associated_item(
463 prim_ty: PrimitiveType,
466 ) -> Option<(Res, ItemFragment)> {
467 let tcx = self.cx.tcx;
469 prim_ty.impls(tcx).find_map(|impl_| {
470 tcx.associated_items(impl_)
471 .find_by_name_and_namespace(tcx, Ident::with_dummy_span(item_name), ns, impl_)
473 let fragment = ItemFragment::from_assoc_item(item);
474 (Res::Primitive(prim_ty), fragment)
479 /// Resolves a string as a macro.
481 /// FIXME(jynelson): Can this be unified with `resolve()`?
487 ) -> Result<Res, ResolutionFailure<'a>> {
488 self.resolve_path(path_str, MacroNS, item_id, module_id).ok_or_else(|| {
489 ResolutionFailure::NotResolved {
493 unresolved: path_str.into(),
498 fn resolve_self_ty(&self, path_str: &str, ns: Namespace, item_id: ItemId) -> Option<Res> {
499 if ns != TypeNS || path_str != "Self" {
503 let tcx = self.cx.tcx;
506 .map(|def_id| match tcx.def_kind(def_id) {
507 def_kind @ (DefKind::AssocFn
508 | DefKind::AssocConst
511 | DefKind::Field) => {
512 let parent_def_id = tcx.parent(def_id);
513 if def_kind == DefKind::Field && tcx.def_kind(parent_def_id) == DefKind::Variant
515 tcx.parent(parent_def_id)
522 .and_then(|self_id| match tcx.def_kind(self_id) {
523 DefKind::Impl => self.def_id_to_res(self_id),
524 def_kind => Some(Res::Def(def_kind, self_id)),
528 /// HACK: Try to search the macro name in the list of all `macro_rules` items in the crate.
529 /// Used when nothing else works, may often give an incorrect result.
530 fn resolve_macro_rules(&self, path_str: &str, ns: Namespace) -> Option<Res> {
538 .get(&Symbol::intern(path_str))
540 .and_then(|res| res.try_into().ok())
543 /// Convenience wrapper around `resolve_rustdoc_path`.
545 /// This also handles resolving `true` and `false` as booleans.
546 /// NOTE: `resolve_rustdoc_path` knows only about paths, not about types.
547 /// Associated items will never be resolved by this function.
555 if let res @ Some(..) = self.resolve_self_ty(path_str, ns, item_id) {
559 // Resolver doesn't know about true, false, and types that aren't paths (e.g. `()`).
563 .doc_link_resolutions
564 .get(&(Symbol::intern(path_str), ns, module_id))
567 self.cx.enter_resolver(|resolver| {
569 ParentScope::module(resolver.expect_module(module_id), resolver);
570 resolver.resolve_rustdoc_path(path_str, ns, parent_scope)
573 .and_then(|res| res.try_into().ok())
574 .or_else(|| resolve_primitive(path_str, ns))
575 .or_else(|| self.resolve_macro_rules(path_str, ns));
576 debug!("{} resolved to {:?} in namespace {:?}", path_str, result, ns);
580 /// Resolves a string as a path within a particular namespace. Returns an
581 /// optional URL fragment in the case of variants and methods.
584 path_str: &'path str,
588 user_fragment: &Option<String>,
589 ) -> Result<(Res, Option<UrlFragment>), ErrorKind<'path>> {
590 let (res, rustdoc_fragment) = self.resolve_inner(path_str, ns, item_id, module_id)?;
591 let chosen_fragment = match (user_fragment, rustdoc_fragment) {
592 (Some(_), Some(r_frag)) => {
593 let diag_res = match r_frag {
594 ItemFragment(_, did) => Res::Def(self.cx.tcx.def_kind(did), did),
596 let failure = AnchorFailure::RustdocAnchorConflict(diag_res);
597 return Err(ErrorKind::AnchorFailure(failure));
599 (Some(u_frag), None) => Some(UrlFragment::UserWritten(u_frag.clone())),
600 (None, Some(r_frag)) => Some(UrlFragment::Item(r_frag)),
601 (None, None) => None,
603 Ok((res, chosen_fragment))
606 fn resolve_inner<'path>(
608 path_str: &'path str,
612 ) -> Result<(Res, Option<ItemFragment>), ErrorKind<'path>> {
613 if let Some(res) = self.resolve_path(path_str, ns, item_id, module_id) {
615 // FIXME(#76467): make this fallthrough to lookup the associated
616 // item a separate function.
617 Res::Def(DefKind::AssocFn | DefKind::AssocConst, _) => assert_eq!(ns, ValueNS),
618 Res::Def(DefKind::AssocTy, _) => assert_eq!(ns, TypeNS),
619 Res::Def(DefKind::Variant, _) => {
620 return handle_variant(self.cx, res);
622 // Not a trait item; just return what we found.
623 _ => return Ok((res, None)),
627 // Try looking for methods and associated items.
628 let mut split = path_str.rsplitn(2, "::");
629 // NB: `split`'s first element is always defined, even if the delimiter was not present.
630 // NB: `item_str` could be empty when resolving in the root namespace (e.g. `::std`).
631 let item_str = split.next().unwrap();
632 let item_name = Symbol::intern(item_str);
633 let path_root = split
635 .map(|f| f.to_owned())
636 // If there's no `::`, it's not an associated item.
637 // So we can be sure that `rustc_resolve` was accurate when it said it wasn't resolved.
639 debug!("found no `::`, assumming {} was correctly not in scope", item_name);
640 ResolutionFailure::NotResolved {
644 unresolved: item_str.into(),
648 // FIXME(#83862): this arbitrarily gives precedence to primitives over modules to support
649 // links to primitives when `#[doc(primitive)]` is present. It should give an ambiguity
650 // error instead and special case *only* modules with `#[doc(primitive)]`, not all
652 resolve_primitive(&path_root, TypeNS)
653 .or_else(|| self.resolve_path(&path_root, TypeNS, item_id, module_id))
655 let (res, fragment) =
656 self.resolve_associated_item(ty_res, item_name, ns, module_id)?;
658 Some(Ok((res, Some(fragment))))
661 if ns == Namespace::ValueNS {
662 self.variant_field(path_str, item_id, module_id)
664 Err(ResolutionFailure::NotResolved {
668 unresolved: path_root.into(),
675 /// Convert a DefId to a Res, where possible.
677 /// This is used for resolving type aliases.
678 fn def_id_to_res(&self, ty_id: DefId) -> Option<Res> {
679 use PrimitiveType::*;
680 Some(match *self.cx.tcx.type_of(ty_id).kind() {
681 ty::Bool => Res::Primitive(Bool),
682 ty::Char => Res::Primitive(Char),
683 ty::Int(ity) => Res::Primitive(ity.into()),
684 ty::Uint(uty) => Res::Primitive(uty.into()),
685 ty::Float(fty) => Res::Primitive(fty.into()),
686 ty::Str => Res::Primitive(Str),
687 ty::Tuple(tys) if tys.is_empty() => Res::Primitive(Unit),
688 ty::Tuple(_) => Res::Primitive(Tuple),
689 ty::Array(..) => Res::Primitive(Array),
690 ty::Slice(_) => Res::Primitive(Slice),
691 ty::RawPtr(_) => Res::Primitive(RawPointer),
692 ty::Ref(..) => Res::Primitive(Reference),
693 ty::FnDef(..) => panic!("type alias to a function definition"),
694 ty::FnPtr(_) => Res::Primitive(Fn),
695 ty::Never => Res::Primitive(Never),
696 ty::Adt(ty::AdtDef(Interned(&ty::AdtDefData { did, .. }, _)), _) | ty::Foreign(did) => {
697 Res::Def(self.cx.tcx.def_kind(did), did)
702 | ty::GeneratorWitness(_)
709 | ty::Error(_) => return None,
713 /// Convert a PrimitiveType to a Ty, where possible.
715 /// This is used for resolving trait impls for primitives
716 fn primitive_type_to_ty(&mut self, prim: PrimitiveType) -> Option<Ty<'tcx>> {
717 use PrimitiveType::*;
718 let tcx = self.cx.tcx;
720 // FIXME: Only simple types are supported here, see if we can support
721 // other types such as Tuple, Array, Slice, etc.
722 // See https://github.com/rust-lang/rust/issues/90703#issuecomment-1004263455
723 Some(tcx.mk_ty(match prim {
728 I8 => ty::Int(ty::IntTy::I8),
729 I16 => ty::Int(ty::IntTy::I16),
730 I32 => ty::Int(ty::IntTy::I32),
731 I64 => ty::Int(ty::IntTy::I64),
732 I128 => ty::Int(ty::IntTy::I128),
733 Isize => ty::Int(ty::IntTy::Isize),
734 F32 => ty::Float(ty::FloatTy::F32),
735 F64 => ty::Float(ty::FloatTy::F64),
736 U8 => ty::Uint(ty::UintTy::U8),
737 U16 => ty::Uint(ty::UintTy::U16),
738 U32 => ty::Uint(ty::UintTy::U32),
739 U64 => ty::Uint(ty::UintTy::U64),
740 U128 => ty::Uint(ty::UintTy::U128),
741 Usize => ty::Uint(ty::UintTy::Usize),
746 /// Resolve an associated item, returning its containing page's `Res`
747 /// and the fragment targeting the associated item on its page.
748 fn resolve_associated_item(
754 ) -> Option<(Res, ItemFragment)> {
755 let tcx = self.cx.tcx;
758 Res::Primitive(prim) => {
759 self.resolve_primitive_associated_item(prim, ns, item_name).or_else(|| {
760 let assoc_item = self
761 .primitive_type_to_ty(prim)
763 resolve_associated_trait_item(ty, module_id, item_name, ns, self.cx)
767 assoc_item.map(|item| {
768 let fragment = ItemFragment::from_assoc_item(&item);
773 Res::Def(DefKind::TyAlias, did) => {
774 // Resolve the link on the type the alias points to.
775 // FIXME: if the associated item is defined directly on the type alias,
776 // it will show up on its documentation page, we should link there instead.
777 let res = self.def_id_to_res(did)?;
778 self.resolve_associated_item(res, item_name, ns, module_id)
781 def_kind @ (DefKind::Struct | DefKind::Union | DefKind::Enum | DefKind::ForeignTy),
784 debug!("looking for associated item named {} for item {:?}", item_name, did);
785 // Checks if item_name is a variant of the `SomeItem` enum
786 if ns == TypeNS && def_kind == DefKind::Enum {
787 match tcx.type_of(did).kind() {
788 ty::Adt(adt_def, _) => {
789 for variant in adt_def.variants() {
790 if variant.name == item_name {
793 ItemFragment(FragmentKind::Variant, variant.def_id),
802 // Checks if item_name belongs to `impl SomeItem`
807 tcx.associated_items(imp).find_by_name_and_namespace(
809 Ident::with_dummy_span(item_name),
815 // There should only ever be one associated item that matches from any inherent impl
817 // Check if item_name belongs to `impl SomeTrait for SomeItem`
818 // FIXME(#74563): This gives precedence to `impl SomeItem`:
819 // Although having both would be ambiguous, use impl version for compatibility's sake.
820 // To handle that properly resolve() would have to support
821 // something like [`ambi_fn`](<SomeStruct as SomeTrait>::ambi_fn)
823 resolve_associated_trait_item(
832 debug!("got associated item {:?}", assoc_item);
834 if let Some(item) = assoc_item {
835 let fragment = ItemFragment::from_assoc_item(&item);
836 return Some((root_res, fragment));
839 if ns != Namespace::ValueNS {
842 debug!("looking for fields named {} for {:?}", item_name, did);
843 // FIXME: this doesn't really belong in `associated_item` (maybe `variant_field` is better?)
844 // NOTE: it's different from variant_field because it only resolves struct fields,
845 // not variant fields (2 path segments, not 3).
847 // We need to handle struct (and union) fields in this code because
848 // syntactically their paths are identical to associated item paths:
849 // `module::Type::field` and `module::Type::Assoc`.
851 // On the other hand, variant fields can't be mistaken for associated
852 // items because they look like this: `module::Type::Variant::field`.
854 // Variants themselves don't need to be handled here, even though
855 // they also look like associated items (`module::Type::Variant`),
856 // because they are real Rust syntax (unlike the intra-doc links
857 // field syntax) and are handled by the compiler's resolver.
858 let def = match tcx.type_of(did).kind() {
859 ty::Adt(def, _) if !def.is_enum() => def,
863 def.non_enum_variant().fields.iter().find(|item| item.name == item_name)?;
864 Some((root_res, ItemFragment(FragmentKind::StructField, field.did)))
866 Res::Def(DefKind::Trait, did) => tcx
867 .associated_items(did)
868 .find_by_name_and_namespace(tcx, Ident::with_dummy_span(item_name), ns, did)
870 let fragment = ItemFragment::from_assoc_item(item);
871 let res = Res::Def(item.kind.as_def_kind(), item.def_id);
878 /// Used for reporting better errors.
880 /// Returns whether the link resolved 'fully' in another namespace.
881 /// 'fully' here means that all parts of the link resolved, not just some path segments.
882 /// This returns the `Res` even if it was erroneous for some reason
883 /// (such as having invalid URL fragments or being in the wrong namespace).
890 extra_fragment: &Option<String>,
892 // resolve() can't be used for macro namespace
893 let result = match ns {
894 Namespace::MacroNS => self
895 .resolve_macro(path_str, item_id, module_id)
896 .map(|res| (res, None))
897 .map_err(ErrorKind::from),
898 Namespace::TypeNS | Namespace::ValueNS => {
899 self.resolve(path_str, ns, item_id, module_id, extra_fragment)
903 let res = match result {
905 if let Some(UrlFragment::Item(ItemFragment(_, id))) = frag {
906 Some(Res::Def(self.cx.tcx.def_kind(id), id))
911 Err(ErrorKind::Resolve(box kind)) => kind.full_res(),
912 Err(ErrorKind::AnchorFailure(AnchorFailure::RustdocAnchorConflict(res))) => Some(res),
913 Err(ErrorKind::AnchorFailure(AnchorFailure::MultipleAnchors)) => None,
919 /// Look to see if a resolved item has an associated item named `item_name`.
921 /// Given `[std::io::Error::source]`, where `source` is unresolved, this would
922 /// find `std::error::Error::source` and return
923 /// `<io::Error as error::Error>::source`.
924 fn resolve_associated_trait_item<'a>(
929 cx: &mut DocContext<'a>,
930 ) -> Option<ty::AssocItem> {
931 // FIXME: this should also consider blanket impls (`impl<T> X for T`). Unfortunately
932 // `get_auto_trait_and_blanket_impls` is broken because the caching behavior is wrong. In the
933 // meantime, just don't look for these blanket impls.
935 // Next consider explicit impls: `impl MyTrait for MyType`
936 // Give precedence to inherent impls.
937 let traits = trait_impls_for(cx, ty, module);
938 debug!("considering traits {:?}", traits);
939 let mut candidates = traits.iter().filter_map(|&(impl_, trait_)| {
941 .associated_items(trait_)
942 .find_by_name_and_namespace(cx.tcx, Ident::with_dummy_span(item_name), ns, trait_)
944 trait_assoc_to_impl_assoc_item(cx.tcx, impl_, trait_assoc.def_id)
945 .unwrap_or(trait_assoc)
948 // FIXME(#74563): warn about ambiguity
949 debug!("the candidates were {:?}", candidates.clone().collect::<Vec<_>>());
950 candidates.next().copied()
953 /// Find the associated item in the impl `impl_id` that corresponds to the
954 /// trait associated item `trait_assoc_id`.
956 /// This function returns `None` if no associated item was found in the impl.
957 /// This can occur when the trait associated item has a default value that is
958 /// not overridden in the impl.
960 /// This is just a wrapper around [`TyCtxt::impl_item_implementor_ids()`] and
961 /// [`TyCtxt::associated_item()`] (with some helpful logging added).
962 #[instrument(level = "debug", skip(tcx))]
963 fn trait_assoc_to_impl_assoc_item<'tcx>(
966 trait_assoc_id: DefId,
967 ) -> Option<&'tcx ty::AssocItem> {
968 let trait_to_impl_assoc_map = tcx.impl_item_implementor_ids(impl_id);
969 debug!(?trait_to_impl_assoc_map);
970 let impl_assoc_id = *trait_to_impl_assoc_map.get(&trait_assoc_id)?;
971 debug!(?impl_assoc_id);
972 let impl_assoc = tcx.associated_item(impl_assoc_id);
977 /// Given a type, return all trait impls in scope in `module` for that type.
978 /// Returns a set of pairs of `(impl_id, trait_id)`.
980 /// NOTE: this cannot be a query because more traits could be available when more crates are compiled!
981 /// So it is not stable to serialize cross-crate.
982 #[instrument(level = "debug", skip(cx))]
983 fn trait_impls_for<'a>(
984 cx: &mut DocContext<'a>,
987 ) -> FxHashSet<(DefId, DefId)> {
989 let iter = cx.resolver_caches.traits_in_scope[&module].iter().flat_map(|trait_candidate| {
990 let trait_ = trait_candidate.def_id;
991 trace!("considering explicit impl for trait {:?}", trait_);
993 // Look at each trait implementation to see if it's an impl for `did`
994 tcx.find_map_relevant_impl(trait_, ty, |impl_| {
995 let trait_ref = tcx.impl_trait_ref(impl_).expect("this is not an inherent impl");
996 // Check if these are the same type.
997 let impl_type = trait_ref.self_ty();
999 "comparing type {} with kind {:?} against type {:?}",
1004 // Fast path: if this is a primitive simple `==` will work
1005 // NOTE: the `match` is necessary; see #92662.
1006 // this allows us to ignore generics because the user input
1007 // may not include the generic placeholders
1008 // e.g. this allows us to match Foo (user comment) with Foo<T> (actual type)
1009 let saw_impl = impl_type == ty
1010 || match (impl_type.kind(), ty.kind()) {
1011 (ty::Adt(impl_def, _), ty::Adt(ty_def, _)) => {
1012 debug!("impl def_id: {:?}, ty def_id: {:?}", impl_def.did(), ty_def.did());
1013 impl_def.did() == ty_def.did()
1018 if saw_impl { Some((impl_, trait_)) } else { None }
1024 /// Check for resolve collisions between a trait and its derive.
1026 /// These are common and we should just resolve to the trait in that case.
1027 fn is_derive_trait_collision<T>(ns: &PerNS<Result<(Res, T), ResolutionFailure<'_>>>) -> bool {
1031 type_ns: Ok((Res::Def(DefKind::Trait, _), _)),
1032 macro_ns: Ok((Res::Def(DefKind::Macro(MacroKind::Derive), _), _)),
1038 impl<'a, 'tcx> DocVisitor for LinkCollector<'a, 'tcx> {
1039 fn visit_item(&mut self, item: &Item) {
1041 item.item_id.as_def_id().and_then(|did| find_nearest_parent_module(self.cx.tcx, did));
1042 if parent_node.is_some() {
1043 trace!("got parent node for {:?} {:?}, id {:?}", item.type_(), item.name, item.item_id);
1046 let inner_docs = item.inner_docs(self.cx.tcx);
1048 if item.is_mod() && inner_docs {
1049 self.mod_ids.push(item.item_id.expect_def_id());
1052 // We want to resolve in the lexical scope of the documentation.
1053 // In the presence of re-exports, this is not the same as the module of the item.
1054 // Rather than merging all documentation into one, resolve it one attribute at a time
1055 // so we know which module it came from.
1056 for (parent_module, doc) in item.attrs.prepare_to_doc_link_resolution() {
1057 if !may_have_doc_links(&doc) {
1060 debug!("combined_docs={}", doc);
1061 // NOTE: if there are links that start in one crate and end in another, this will not resolve them.
1062 // This is a degenerate case and it's not supported by rustdoc.
1063 let parent_node = parent_module.or(parent_node);
1064 let mut tmp_links = self
1069 .expect("`markdown_links` are already borrowed");
1070 if !tmp_links.contains_key(&doc) {
1071 tmp_links.insert(doc.clone(), preprocessed_markdown_links(&doc));
1073 for md_link in &tmp_links[&doc] {
1074 let link = self.resolve_link(&item, &doc, parent_node, md_link);
1075 if let Some(link) = link {
1076 self.cx.cache.intra_doc_links.entry(item.item_id).or_default().push(link);
1079 self.cx.resolver_caches.markdown_links = Some(tmp_links);
1084 self.mod_ids.push(item.item_id.expect_def_id());
1087 self.visit_item_recur(item);
1090 self.visit_item_recur(item)
1095 enum PreprocessingError {
1096 Anchor(AnchorFailure),
1097 Disambiguator(Range<usize>, String),
1098 Resolution(ResolutionFailure<'static>, String, Option<Disambiguator>),
1101 impl From<AnchorFailure> for PreprocessingError {
1102 fn from(err: AnchorFailure) -> Self {
1108 struct PreprocessingInfo {
1110 disambiguator: Option<Disambiguator>,
1111 extra_fragment: Option<String>,
1115 // Not a typedef to avoid leaking several private structures from this module.
1116 crate struct PreprocessedMarkdownLink(Result<PreprocessingInfo, PreprocessingError>, MarkdownLink);
1119 /// - `None` if the link should be ignored.
1120 /// - `Some(Err)` if the link should emit an error
1121 /// - `Some(Ok)` if the link is valid
1123 /// `link_buffer` is needed for lifetime reasons; it will always be overwritten and the contents ignored.
1125 ori_link: &MarkdownLink,
1126 ) -> Option<Result<PreprocessingInfo, PreprocessingError>> {
1127 // [] is mostly likely not supposed to be a link
1128 if ori_link.link.is_empty() {
1132 // Bail early for real links.
1133 if ori_link.link.contains('/') {
1137 let stripped = ori_link.link.replace('`', "");
1138 let mut parts = stripped.split('#');
1140 let link = parts.next().unwrap();
1141 if link.trim().is_empty() {
1142 // This is an anchor to an element of the current page, nothing to do in here!
1145 let extra_fragment = parts.next();
1146 if parts.next().is_some() {
1147 // A valid link can't have multiple #'s
1148 return Some(Err(AnchorFailure::MultipleAnchors.into()));
1151 // Parse and strip the disambiguator from the link, if present.
1152 let (disambiguator, path_str, link_text) = match Disambiguator::from_str(link) {
1153 Ok(Some((d, path, link_text))) => (Some(d), path.trim(), link_text.trim()),
1154 Ok(None) => (None, link.trim(), link.trim()),
1155 Err((err_msg, relative_range)) => {
1156 // Only report error if we would not have ignored this link. See issue #83859.
1157 if !should_ignore_link_with_disambiguators(link) {
1158 let no_backticks_range = range_between_backticks(ori_link);
1159 let disambiguator_range = (no_backticks_range.start + relative_range.start)
1160 ..(no_backticks_range.start + relative_range.end);
1161 return Some(Err(PreprocessingError::Disambiguator(disambiguator_range, err_msg)));
1168 if should_ignore_link(path_str) {
1172 // Strip generics from the path.
1173 let path_str = if path_str.contains(['<', '>'].as_slice()) {
1174 match strip_generics_from_path(path_str) {
1177 debug!("link has malformed generics: {}", path_str);
1178 return Some(Err(PreprocessingError::Resolution(
1180 path_str.to_owned(),
1189 // Sanity check to make sure we don't have any angle brackets after stripping generics.
1190 assert!(!path_str.contains(['<', '>'].as_slice()));
1192 // The link is not an intra-doc link if it still contains spaces after stripping generics.
1193 if path_str.contains(' ') {
1197 Some(Ok(PreprocessingInfo {
1200 extra_fragment: extra_fragment.map(|frag| frag.to_owned()),
1201 link_text: link_text.to_owned(),
1205 fn preprocessed_markdown_links(s: &str) -> Vec<PreprocessedMarkdownLink> {
1206 markdown_links(s, |link| {
1207 preprocess_link(&link).map(|pp_link| PreprocessedMarkdownLink(pp_link, link))
1211 impl LinkCollector<'_, '_> {
1212 /// This is the entry point for resolving an intra-doc link.
1214 /// FIXME(jynelson): this is way too many arguments
1219 parent_node: Option<DefId>,
1220 link: &PreprocessedMarkdownLink,
1221 ) -> Option<ItemLink> {
1222 let PreprocessedMarkdownLink(pp_link, ori_link) = link;
1223 trace!("considering link '{}'", ori_link.link);
1225 let diag_info = DiagnosticInfo {
1228 ori_link: &ori_link.link,
1229 link_range: ori_link.range.clone(),
1232 let PreprocessingInfo { path_str, disambiguator, extra_fragment, link_text } = match pp_link
1237 PreprocessingError::Anchor(err) => anchor_failure(self.cx, diag_info, *err),
1238 PreprocessingError::Disambiguator(range, msg) => {
1239 disambiguator_error(self.cx, diag_info, range.clone(), msg)
1241 PreprocessingError::Resolution(err, path_str, disambiguator) => {
1247 smallvec![err.clone()],
1254 let disambiguator = *disambiguator;
1256 let inner_docs = item.inner_docs(self.cx.tcx);
1258 // In order to correctly resolve intra-doc links we need to
1259 // pick a base AST node to work from. If the documentation for
1260 // this module came from an inner comment (//!) then we anchor
1261 // our name resolution *inside* the module. If, on the other
1262 // hand it was an outer comment (///) then we anchor the name
1263 // resolution in the parent module on the basis that the names
1264 // used are more likely to be intended to be parent names. For
1265 // this, we set base_node to None for inner comments since
1266 // we've already pushed this node onto the resolution stack but
1267 // for outer comments we explicitly try and resolve against the
1268 // parent_node first.
1270 if item.is_mod() && inner_docs { self.mod_ids.last().copied() } else { parent_node };
1272 let Some(module_id) = base_node else {
1274 debug!("attempting to resolve item without parent module: {}", path_str);
1280 smallvec![ResolutionFailure::NoParentItem],
1285 let (mut res, fragment) = self.resolve_with_disambiguator_cached(
1287 item_id: item.item_id,
1290 path_str: path_str.to_owned(),
1291 extra_fragment: extra_fragment.clone(),
1293 diag_info.clone(), // this struct should really be Copy, but Range is not :(
1294 matches!(ori_link.kind, LinkType::Reference | LinkType::Shortcut),
1297 // Check for a primitive which might conflict with a module
1298 // Report the ambiguity and require that the user specify which one they meant.
1299 // FIXME: could there ever be a primitive not in the type namespace?
1302 None | Some(Disambiguator::Namespace(Namespace::TypeNS) | Disambiguator::Primitive)
1303 ) && !matches!(res, Res::Primitive(_))
1305 if let Some(prim) = resolve_primitive(path_str, TypeNS) {
1307 if matches!(disambiguator, Some(Disambiguator::Primitive)) {
1310 // `[char]` when a `char` module is in scope
1311 let candidates = vec![res, prim];
1312 ambiguity_error(self.cx, diag_info, path_str, candidates);
1319 Res::Primitive(prim) => {
1320 if let Some(UrlFragment::Item(ItemFragment(_, id))) = fragment {
1321 // We're actually resolving an associated item of a primitive, so we need to
1322 // verify the disambiguator (if any) matches the type of the associated item.
1323 // This case should really follow the same flow as the `Res::Def` branch below,
1324 // but attempting to add a call to `clean::register_res` causes an ICE. @jyn514
1325 // thinks `register_res` is only needed for cross-crate re-exports, but Rust
1326 // doesn't allow statements like `use str::trim;`, making this a (hopefully)
1327 // valid omission. See https://github.com/rust-lang/rust/pull/80660#discussion_r551585677
1328 // for discussion on the matter.
1329 let kind = self.cx.tcx.def_kind(id);
1330 self.verify_disambiguator(
1340 // FIXME: it would be nice to check that the feature gate was enabled in the original crate, not just ignore it altogether.
1341 // However I'm not sure how to check that across crates.
1342 if prim == PrimitiveType::RawPointer
1343 && item.item_id.is_local()
1344 && !self.cx.tcx.features().intra_doc_pointers
1346 self.report_rawptr_assoc_feature_gate(dox, &ori_link, item);
1349 match disambiguator {
1350 Some(Disambiguator::Primitive | Disambiguator::Namespace(_)) | None => {}
1352 self.report_disambiguator_mismatch(
1353 path_str, &ori_link, other, res, &diag_info,
1361 link: ori_link.link.clone(),
1362 link_text: link_text.clone(),
1363 did: res.def_id(self.cx.tcx),
1367 Res::Def(kind, id) => {
1368 let (kind_for_dis, id_for_dis) =
1369 if let Some(UrlFragment::Item(ItemFragment(_, id))) = fragment {
1370 (self.cx.tcx.def_kind(id), id)
1374 self.verify_disambiguator(
1383 let id = clean::register_res(self.cx, rustc_hir::def::Res::Def(kind, id));
1385 link: ori_link.link.clone(),
1386 link_text: link_text.clone(),
1394 fn verify_disambiguator(
1397 ori_link: &MarkdownLink,
1400 disambiguator: Option<Disambiguator>,
1402 diag_info: &DiagnosticInfo<'_>,
1404 debug!("intra-doc link to {} resolved to {:?}", path_str, (kind, id));
1406 // Disallow e.g. linking to enums with `struct@`
1407 debug!("saw kind {:?} with disambiguator {:?}", kind, disambiguator);
1408 match (kind, disambiguator) {
1409 | (DefKind::Const | DefKind::ConstParam | DefKind::AssocConst | DefKind::AnonConst, Some(Disambiguator::Kind(DefKind::Const)))
1410 // NOTE: this allows 'method' to mean both normal functions and associated functions
1411 // This can't cause ambiguity because both are in the same namespace.
1412 | (DefKind::Fn | DefKind::AssocFn, Some(Disambiguator::Kind(DefKind::Fn)))
1413 // These are namespaces; allow anything in the namespace to match
1414 | (_, Some(Disambiguator::Namespace(_)))
1415 // If no disambiguator given, allow anything
1417 // All of these are valid, so do nothing
1419 (actual, Some(Disambiguator::Kind(expected))) if actual == expected => {}
1420 (_, Some(specified @ Disambiguator::Kind(_) | specified @ Disambiguator::Primitive)) => {
1421 self.report_disambiguator_mismatch(path_str,ori_link,specified, Res::Def(kind, id),diag_info);
1426 // item can be non-local e.g. when using #[doc(primitive = "pointer")]
1427 if let Some((src_id, dst_id)) = id
1429 // The `expect_def_id()` should be okay because `local_def_id_to_hir_id`
1430 // would presumably panic if a fake `DefIndex` were passed.
1431 .and_then(|dst_id| {
1432 item.item_id.expect_def_id().as_local().map(|src_id| (src_id, dst_id))
1435 if self.cx.tcx.privacy_access_levels(()).is_exported(src_id)
1436 && !self.cx.tcx.privacy_access_levels(()).is_exported(dst_id)
1438 privacy_error(self.cx, diag_info, path_str);
1445 fn report_disambiguator_mismatch(
1448 ori_link: &MarkdownLink,
1449 specified: Disambiguator,
1451 diag_info: &DiagnosticInfo<'_>,
1453 // The resolved item did not match the disambiguator; give a better error than 'not found'
1454 let msg = format!("incompatible link kind for `{}`", path_str);
1455 let callback = |diag: &mut Diagnostic, sp: Option<rustc_span::Span>| {
1457 "this link resolved to {} {}, which is not {} {}",
1460 specified.article(),
1463 if let Some(sp) = sp {
1464 diag.span_label(sp, ¬e);
1468 suggest_disambiguator(resolved, diag, path_str, &ori_link.link, sp);
1470 report_diagnostic(self.cx.tcx, BROKEN_INTRA_DOC_LINKS, &msg, &diag_info, callback);
1473 fn report_rawptr_assoc_feature_gate(&self, dox: &str, ori_link: &MarkdownLink, item: &Item) {
1475 super::source_span_for_markdown_range(self.cx.tcx, dox, &ori_link.range, &item.attrs)
1476 .unwrap_or_else(|| item.attr_span(self.cx.tcx));
1477 rustc_session::parse::feature_err(
1478 &self.cx.tcx.sess.parse_sess,
1479 sym::intra_doc_pointers,
1481 "linking to associated items of raw pointers is experimental",
1483 .note("rustdoc does not allow disambiguating between `*const` and `*mut`, and pointers are unstable until it does")
1487 fn resolve_with_disambiguator_cached(
1489 key: ResolutionInfo,
1490 diag: DiagnosticInfo<'_>,
1491 cache_resolution_failure: bool,
1492 ) -> Option<(Res, Option<UrlFragment>)> {
1493 if let Some(ref cached) = self.visited_links.get(&key) {
1496 return Some(cached.res.clone());
1498 None if cache_resolution_failure => return None,
1500 // Although we hit the cache and found a resolution error, this link isn't
1501 // supposed to cache those. Run link resolution again to emit the expected
1502 // resolution error.
1507 let res = self.resolve_with_disambiguator(&key, diag);
1509 // Cache only if resolved successfully - don't silence duplicate errors
1510 if let Some(res) = res {
1511 // Store result for the actual namespace
1512 self.visited_links.insert(key, Some(CachedLink { res: res.clone() }));
1516 if cache_resolution_failure {
1517 // For reference-style links we only want to report one resolution error
1518 // so let's cache them as well.
1519 self.visited_links.insert(key, None);
1526 /// After parsing the disambiguator, resolve the main part of the link.
1527 // FIXME(jynelson): wow this is just so much
1528 fn resolve_with_disambiguator(
1530 key: &ResolutionInfo,
1531 diag: DiagnosticInfo<'_>,
1532 ) -> Option<(Res, Option<UrlFragment>)> {
1533 let disambiguator = key.dis;
1534 let path_str = &key.path_str;
1535 let item_id = key.item_id;
1536 let base_node = key.module_id;
1537 let extra_fragment = &key.extra_fragment;
1539 match disambiguator.map(Disambiguator::ns) {
1540 Some(expected_ns @ (ValueNS | TypeNS)) => {
1541 match self.resolve(path_str, expected_ns, item_id, base_node, extra_fragment) {
1542 Ok(res) => Some(res),
1543 Err(ErrorKind::Resolve(box mut kind)) => {
1544 // We only looked in one namespace. Try to give a better error if possible.
1545 if kind.full_res().is_none() {
1546 let other_ns = if expected_ns == ValueNS { TypeNS } else { ValueNS };
1547 // FIXME: really it should be `resolution_failure` that does this, not `resolve_with_disambiguator`
1548 // See https://github.com/rust-lang/rust/pull/76955#discussion_r493953382 for a good approach
1549 for new_ns in [other_ns, MacroNS] {
1550 if let Some(res) = self.check_full_res(
1557 kind = ResolutionFailure::WrongNamespace { res, expected_ns };
1562 resolution_failure(self, diag, path_str, disambiguator, smallvec![kind]);
1563 // This could just be a normal link or a broken link
1564 // we could potentially check if something is
1565 // "intra-doc-link-like" and warn in that case.
1568 Err(ErrorKind::AnchorFailure(msg)) => {
1569 anchor_failure(self.cx, diag, msg);
1576 let mut candidates = PerNS {
1578 .resolve_macro(path_str, item_id, base_node)
1579 .map(|res| (res, extra_fragment.clone().map(UrlFragment::UserWritten))),
1580 type_ns: match self.resolve(
1588 debug!("got res in TypeNS: {:?}", res);
1591 Err(ErrorKind::AnchorFailure(msg)) => {
1592 anchor_failure(self.cx, diag, msg);
1595 Err(ErrorKind::Resolve(box kind)) => Err(kind),
1597 value_ns: match self.resolve(
1605 Err(ErrorKind::AnchorFailure(msg)) => {
1606 anchor_failure(self.cx, diag, msg);
1609 Err(ErrorKind::Resolve(box kind)) => Err(kind),
1611 .and_then(|(res, fragment)| {
1612 // Constructors are picked up in the type namespace.
1614 Res::Def(DefKind::Ctor(..), _) => {
1615 Err(ResolutionFailure::WrongNamespace { res, expected_ns: TypeNS })
1618 match (fragment, extra_fragment.clone()) {
1619 (Some(fragment), Some(_)) => {
1620 // Shouldn't happen but who knows?
1621 Ok((res, Some(fragment)))
1623 (fragment, None) => Ok((res, fragment)),
1624 (None, fragment) => {
1625 Ok((res, fragment.map(UrlFragment::UserWritten)))
1633 let len = candidates.iter().filter(|res| res.is_ok()).count();
1641 candidates.into_iter().filter_map(|res| res.err()).collect(),
1643 // this could just be a normal link
1648 Some(candidates.into_iter().find_map(|res| res.ok()).unwrap())
1649 } else if len == 2 && is_derive_trait_collision(&candidates) {
1650 Some(candidates.type_ns.unwrap())
1652 if is_derive_trait_collision(&candidates) {
1653 candidates.macro_ns = Err(ResolutionFailure::Dummy);
1655 // If we're reporting an ambiguity, don't mention the namespaces that failed
1656 let candidates = candidates.map(|candidate| candidate.ok().map(|(res, _)| res));
1657 ambiguity_error(self.cx, diag, path_str, candidates.present_items().collect());
1662 match self.resolve_macro(path_str, item_id, base_node) {
1663 Ok(res) => Some((res, extra_fragment.clone().map(UrlFragment::UserWritten))),
1665 // `resolve_macro` only looks in the macro namespace. Try to give a better error if possible.
1666 for ns in [TypeNS, ValueNS] {
1667 if let Some(res) = self.check_full_res(
1675 ResolutionFailure::WrongNamespace { res, expected_ns: MacroNS };
1679 resolution_failure(self, diag, path_str, disambiguator, smallvec![kind]);
1688 /// Get the section of a link between the backticks,
1689 /// or the whole link if there aren't any backticks.
1697 fn range_between_backticks(ori_link: &MarkdownLink) -> Range<usize> {
1698 let after_first_backtick_group = ori_link.link.bytes().position(|b| b != b'`').unwrap_or(0);
1699 let before_second_backtick_group = ori_link
1702 .skip(after_first_backtick_group)
1703 .position(|b| b == b'`')
1704 .unwrap_or(ori_link.link.len());
1705 (ori_link.range.start + after_first_backtick_group)
1706 ..(ori_link.range.start + before_second_backtick_group)
1709 /// Returns true if we should ignore `link` due to it being unlikely
1710 /// that it is an intra-doc link. `link` should still have disambiguators
1711 /// if there were any.
1713 /// The difference between this and [`should_ignore_link()`] is that this
1714 /// check should only be used on links that still have disambiguators.
1715 fn should_ignore_link_with_disambiguators(link: &str) -> bool {
1716 link.contains(|ch: char| !(ch.is_alphanumeric() || ":_<>, !*&;@()".contains(ch)))
1719 /// Returns true if we should ignore `path_str` due to it being unlikely
1720 /// that it is an intra-doc link.
1721 fn should_ignore_link(path_str: &str) -> bool {
1722 path_str.contains(|ch: char| !(ch.is_alphanumeric() || ":_<>, !*&;".contains(ch)))
1725 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
1726 /// Disambiguators for a link.
1727 enum Disambiguator {
1730 /// This is buggy, see <https://github.com/rust-lang/rust/pull/77875#discussion_r503583103>
1732 /// `struct@` or `f()`
1735 Namespace(Namespace),
1738 impl Disambiguator {
1739 /// Given a link, parse and return `(disambiguator, path_str, link_text)`.
1741 /// This returns `Ok(Some(...))` if a disambiguator was found,
1742 /// `Ok(None)` if no disambiguator was found, or `Err(...)`
1743 /// if there was a problem with the disambiguator.
1744 fn from_str(link: &str) -> Result<Option<(Self, &str, &str)>, (String, Range<usize>)> {
1745 use Disambiguator::{Kind, Namespace as NS, Primitive};
1747 if let Some(idx) = link.find('@') {
1748 let (prefix, rest) = link.split_at(idx);
1749 let d = match prefix {
1750 "struct" => Kind(DefKind::Struct),
1751 "enum" => Kind(DefKind::Enum),
1752 "trait" => Kind(DefKind::Trait),
1753 "union" => Kind(DefKind::Union),
1754 "module" | "mod" => Kind(DefKind::Mod),
1755 "const" | "constant" => Kind(DefKind::Const),
1756 "static" => Kind(DefKind::Static(Mutability::Not)),
1757 "function" | "fn" | "method" => Kind(DefKind::Fn),
1758 "derive" => Kind(DefKind::Macro(MacroKind::Derive)),
1759 "type" => NS(Namespace::TypeNS),
1760 "value" => NS(Namespace::ValueNS),
1761 "macro" => NS(Namespace::MacroNS),
1762 "prim" | "primitive" => Primitive,
1763 _ => return Err((format!("unknown disambiguator `{}`", prefix), 0..idx)),
1765 Ok(Some((d, &rest[1..], &rest[1..])))
1768 ("!()", DefKind::Macro(MacroKind::Bang)),
1769 ("!{}", DefKind::Macro(MacroKind::Bang)),
1770 ("![]", DefKind::Macro(MacroKind::Bang)),
1771 ("()", DefKind::Fn),
1772 ("!", DefKind::Macro(MacroKind::Bang)),
1774 for (suffix, kind) in suffixes {
1775 if let Some(path_str) = link.strip_suffix(suffix) {
1776 // Avoid turning `!` or `()` into an empty string
1777 if !path_str.is_empty() {
1778 return Ok(Some((Kind(kind), path_str, link)));
1786 fn ns(self) -> Namespace {
1788 Self::Namespace(n) => n,
1790 k.ns().expect("only DefKinds with a valid namespace can be disambiguators")
1792 Self::Primitive => TypeNS,
1796 fn article(self) -> &'static str {
1798 Self::Namespace(_) => panic!("article() doesn't make sense for namespaces"),
1799 Self::Kind(k) => k.article(),
1800 Self::Primitive => "a",
1804 fn descr(self) -> &'static str {
1806 Self::Namespace(n) => n.descr(),
1807 // HACK(jynelson): the source of `DefKind::descr` only uses the DefId for
1808 // printing "module" vs "crate" so using the wrong ID is not a huge problem
1809 Self::Kind(k) => k.descr(CRATE_DEF_ID.to_def_id()),
1810 Self::Primitive => "builtin type",
1815 /// A suggestion to show in a diagnostic.
1818 Prefix(&'static str),
1823 /// `foo` without any disambiguator
1824 RemoveDisambiguator,
1828 fn descr(&self) -> Cow<'static, str> {
1830 Self::Prefix(x) => format!("prefix with `{}@`", x).into(),
1831 Self::Function => "add parentheses".into(),
1832 Self::Macro => "add an exclamation mark".into(),
1833 Self::RemoveDisambiguator => "remove the disambiguator".into(),
1837 fn as_help(&self, path_str: &str) -> String {
1838 // FIXME: if this is an implied shortcut link, it's bad style to suggest `@`
1840 Self::Prefix(prefix) => format!("{}@{}", prefix, path_str),
1841 Self::Function => format!("{}()", path_str),
1842 Self::Macro => format!("{}!", path_str),
1843 Self::RemoveDisambiguator => path_str.into(),
1851 sp: rustc_span::Span,
1852 ) -> Vec<(rustc_span::Span, String)> {
1853 let inner_sp = match ori_link.find('(') {
1854 Some(index) => sp.with_hi(sp.lo() + BytePos(index as _)),
1857 let inner_sp = match ori_link.find('!') {
1858 Some(index) => inner_sp.with_hi(inner_sp.lo() + BytePos(index as _)),
1861 let inner_sp = match ori_link.find('@') {
1862 Some(index) => inner_sp.with_lo(inner_sp.lo() + BytePos(index as u32 + 1)),
1866 Self::Prefix(prefix) => {
1867 // FIXME: if this is an implied shortcut link, it's bad style to suggest `@`
1868 let mut sugg = vec![(sp.with_hi(inner_sp.lo()), format!("{}@", prefix))];
1869 if sp.hi() != inner_sp.hi() {
1870 sugg.push((inner_sp.shrink_to_hi().with_hi(sp.hi()), String::new()));
1875 let mut sugg = vec![(inner_sp.shrink_to_hi().with_hi(sp.hi()), "()".to_string())];
1876 if sp.lo() != inner_sp.lo() {
1877 sugg.push((inner_sp.shrink_to_lo().with_lo(sp.lo()), String::new()));
1882 let mut sugg = vec![(inner_sp.shrink_to_hi(), "!".to_string())];
1883 if sp.lo() != inner_sp.lo() {
1884 sugg.push((inner_sp.shrink_to_lo().with_lo(sp.lo()), String::new()));
1888 Self::RemoveDisambiguator => vec![(sp, path_str.into())],
1893 /// Reports a diagnostic for an intra-doc link.
1895 /// If no link range is provided, or the source span of the link cannot be determined, the span of
1896 /// the entire documentation block is used for the lint. If a range is provided but the span
1897 /// calculation fails, a note is added to the diagnostic pointing to the link in the markdown.
1899 /// The `decorate` callback is invoked in all cases to allow further customization of the
1900 /// diagnostic before emission. If the span of the link was able to be determined, the second
1901 /// parameter of the callback will contain it, and the primary span of the diagnostic will be set
1903 fn report_diagnostic(
1905 lint: &'static Lint,
1907 DiagnosticInfo { item, ori_link: _, dox, link_range }: &DiagnosticInfo<'_>,
1908 decorate: impl FnOnce(&mut Diagnostic, Option<rustc_span::Span>),
1910 let Some(hir_id) = DocContext::as_local_hir_id(tcx, item.item_id)
1912 // If non-local, no need to check anything.
1913 info!("ignoring warning from parent crate: {}", msg);
1917 let sp = item.attr_span(tcx);
1919 tcx.struct_span_lint_hir(lint, hir_id, sp, |lint| {
1920 let mut diag = lint.build(msg);
1923 super::source_span_for_markdown_range(tcx, dox, link_range, &item.attrs).map(|sp| {
1924 if dox.as_bytes().get(link_range.start) == Some(&b'`')
1925 && dox.as_bytes().get(link_range.end - 1) == Some(&b'`')
1927 sp.with_lo(sp.lo() + BytePos(1)).with_hi(sp.hi() - BytePos(1))
1933 if let Some(sp) = span {
1936 // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
1939 // last_new_line_offset
1940 let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
1941 let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
1943 // Print the line containing the `link_range` and manually mark it with '^'s.
1945 "the link appears in this line:\n\n{line}\n\
1946 {indicator: <before$}{indicator:^<found$}",
1949 before = link_range.start - last_new_line_offset,
1950 found = link_range.len(),
1954 decorate(&mut diag, span);
1960 /// Reports a link that failed to resolve.
1962 /// This also tries to resolve any intermediate path segments that weren't
1963 /// handled earlier. For example, if passed `Item::Crate(std)` and `path_str`
1964 /// `std::io::Error::x`, this will resolve `std::io::Error`.
1965 fn resolution_failure(
1966 collector: &mut LinkCollector<'_, '_>,
1967 diag_info: DiagnosticInfo<'_>,
1969 disambiguator: Option<Disambiguator>,
1970 kinds: SmallVec<[ResolutionFailure<'_>; 3]>,
1972 let tcx = collector.cx.tcx;
1975 BROKEN_INTRA_DOC_LINKS,
1976 &format!("unresolved link to `{}`", path_str),
1979 let item = |res: Res| format!("the {} `{}`", res.descr(), res.name(tcx),);
1980 let assoc_item_not_allowed = |res: Res| {
1981 let name = res.name(tcx);
1983 "`{}` is {} {}, not a module or type, and cannot have associated items",
1989 // ignore duplicates
1990 let mut variants_seen = SmallVec::<[_; 3]>::new();
1991 for mut failure in kinds {
1992 let variant = std::mem::discriminant(&failure);
1993 if variants_seen.contains(&variant) {
1996 variants_seen.push(variant);
1998 if let ResolutionFailure::NotResolved {
2007 let item_id = *item_id;
2008 let module_id = *module_id;
2009 // FIXME(jynelson): this might conflict with my `Self` fix in #76467
2010 // FIXME: maybe use itertools `collect_tuple` instead?
2011 fn split(path: &str) -> Option<(&str, &str)> {
2012 let mut splitter = path.rsplitn(2, "::");
2013 splitter.next().and_then(|right| splitter.next().map(|left| (left, right)))
2016 // Check if _any_ parent of the path gets resolved.
2017 // If so, report it and say the first which failed; if not, say the first path segment didn't resolve.
2018 let mut name = path_str;
2020 let Some((start, end)) = split(name) else {
2021 // avoid bug that marked [Quux::Z] as missing Z, not Quux
2022 if partial_res.is_none() {
2023 *unresolved = name.into();
2028 for ns in [TypeNS, ValueNS, MacroNS] {
2030 collector.check_full_res(ns, start, item_id, module_id, &None)
2032 debug!("found partial_res={:?}", res);
2033 *partial_res = Some(res);
2034 *unresolved = end.into();
2038 *unresolved = end.into();
2041 let last_found_module = match *partial_res {
2042 Some(Res::Def(DefKind::Mod, id)) => Some(id),
2043 None => Some(module_id),
2046 // See if this was a module: `[path]` or `[std::io::nope]`
2047 if let Some(module) = last_found_module {
2048 let note = if partial_res.is_some() {
2049 // Part of the link resolved; e.g. `std::io::nonexistent`
2050 let module_name = tcx.item_name(module);
2051 format!("no item named `{}` in module `{}`", unresolved, module_name)
2053 // None of the link resolved; e.g. `Notimported`
2054 format!("no item named `{}` in scope", unresolved)
2056 if let Some(span) = sp {
2057 diag.span_label(span, ¬e);
2062 // If the link has `::` in it, assume it was meant to be an intra-doc link.
2063 // Otherwise, the `[]` might be unrelated.
2064 // FIXME: don't show this for autolinks (`<>`), `()` style links, or reference links
2065 if !path_str.contains("::") {
2066 diag.help(r#"to escape `[` and `]` characters, add '\' before them like `\[` or `\]`"#);
2072 // Otherwise, it must be an associated item or variant
2073 let res = partial_res.expect("None case was handled by `last_found_module`");
2074 let name = res.name(tcx);
2075 let kind = match res {
2076 Res::Def(kind, _) => Some(kind),
2077 Res::Primitive(_) => None,
2079 let path_description = if let Some(kind) = kind {
2081 Mod | ForeignMod => "inner item",
2082 Struct => "field or associated item",
2083 Enum | Union => "variant or associated item",
2101 let note = assoc_item_not_allowed(res);
2102 if let Some(span) = sp {
2103 diag.span_label(span, ¬e);
2109 Trait | TyAlias | ForeignTy | OpaqueTy | TraitAlias | TyParam
2110 | Static(_) => "associated item",
2111 Impl | GlobalAsm => unreachable!("not a path"),
2117 "the {} `{}` has no {} named `{}`",
2120 disambiguator.map_or(path_description, |d| d.descr()),
2123 if let Some(span) = sp {
2124 diag.span_label(span, ¬e);
2131 let note = match failure {
2132 ResolutionFailure::NotResolved { .. } => unreachable!("handled above"),
2133 ResolutionFailure::Dummy => continue,
2134 ResolutionFailure::WrongNamespace { res, expected_ns } => {
2135 suggest_disambiguator(res, diag, path_str, diag_info.ori_link, sp);
2138 "this link resolves to {}, which is not in the {} namespace",
2143 ResolutionFailure::NoParentItem => {
2144 // FIXME(eddyb) this doesn't belong here, whatever made
2145 // the `ResolutionFailure::NoParentItem` should emit an
2146 // immediate or delayed `span_bug` about the issue.
2147 tcx.sess.delay_span_bug(
2148 sp.unwrap_or(DUMMY_SP),
2149 "intra-doc link missing parent item",
2152 "BUG: all intra-doc links should have a parent item".to_owned()
2154 ResolutionFailure::MalformedGenerics(variant) => match variant {
2155 MalformedGenerics::UnbalancedAngleBrackets => {
2156 String::from("unbalanced angle brackets")
2158 MalformedGenerics::MissingType => {
2159 String::from("missing type for generic parameters")
2161 MalformedGenerics::HasFullyQualifiedSyntax => {
2162 diag.note("see https://github.com/rust-lang/rust/issues/74563 for more information");
2163 String::from("fully-qualified syntax is unsupported")
2165 MalformedGenerics::InvalidPathSeparator => {
2166 String::from("has invalid path separator")
2168 MalformedGenerics::TooManyAngleBrackets => {
2169 String::from("too many angle brackets")
2171 MalformedGenerics::EmptyAngleBrackets => {
2172 String::from("empty angle brackets")
2176 if let Some(span) = sp {
2177 diag.span_label(span, ¬e);
2186 /// Report an anchor failure.
2187 fn anchor_failure(cx: &DocContext<'_>, diag_info: DiagnosticInfo<'_>, failure: AnchorFailure) {
2188 let (msg, anchor_idx) = match failure {
2189 AnchorFailure::MultipleAnchors => {
2190 (format!("`{}` contains multiple anchors", diag_info.ori_link), 1)
2192 AnchorFailure::RustdocAnchorConflict(res) => (
2194 "`{}` contains an anchor, but links to {kind}s are already anchored",
2202 report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, &msg, &diag_info, |diag, sp| {
2203 if let Some(mut sp) = sp {
2204 if let Some((fragment_offset, _)) =
2205 diag_info.ori_link.char_indices().filter(|(_, x)| *x == '#').nth(anchor_idx)
2207 sp = sp.with_lo(sp.lo() + BytePos(fragment_offset as _));
2209 diag.span_label(sp, "invalid anchor");
2211 if let AnchorFailure::RustdocAnchorConflict(Res::Primitive(_)) = failure {
2212 if let Some(sp) = sp {
2213 span_bug!(sp, "anchors should be allowed now");
2215 bug!("anchors should be allowed now");
2221 /// Report an error in the link disambiguator.
2222 fn disambiguator_error(
2223 cx: &DocContext<'_>,
2224 mut diag_info: DiagnosticInfo<'_>,
2225 disambiguator_range: Range<usize>,
2228 diag_info.link_range = disambiguator_range;
2229 report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, _sp| {
2231 "see {}/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
2232 crate::DOC_RUST_LANG_ORG_CHANNEL
2238 /// Report an ambiguity error, where there were multiple possible resolutions.
2240 cx: &DocContext<'_>,
2241 diag_info: DiagnosticInfo<'_>,
2243 candidates: Vec<Res>,
2245 let mut msg = format!("`{}` is ", path_str);
2247 match candidates.as_slice() {
2248 [first_def, second_def] => {
2250 "both {} {} and {} {}",
2251 first_def.article(),
2253 second_def.article(),
2258 let mut candidates = candidates.iter().peekable();
2259 while let Some(res) = candidates.next() {
2260 if candidates.peek().is_some() {
2261 msg += &format!("{} {}, ", res.article(), res.descr());
2263 msg += &format!("and {} {}", res.article(), res.descr());
2269 report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, &msg, &diag_info, |diag, sp| {
2270 if let Some(sp) = sp {
2271 diag.span_label(sp, "ambiguous link");
2273 diag.note("ambiguous link");
2276 for res in candidates {
2277 suggest_disambiguator(res, diag, path_str, diag_info.ori_link, sp);
2282 /// In case of an ambiguity or mismatched disambiguator, suggest the correct
2284 fn suggest_disambiguator(
2286 diag: &mut Diagnostic,
2289 sp: Option<rustc_span::Span>,
2291 let suggestion = res.disambiguator_suggestion();
2292 let help = format!("to link to the {}, {}", res.descr(), suggestion.descr());
2294 if let Some(sp) = sp {
2295 let mut spans = suggestion.as_help_span(path_str, ori_link, sp);
2296 if spans.len() > 1 {
2297 diag.multipart_suggestion(&help, spans, Applicability::MaybeIncorrect);
2299 let (sp, suggestion_text) = spans.pop().unwrap();
2300 diag.span_suggestion_verbose(sp, &help, suggestion_text, Applicability::MaybeIncorrect);
2303 diag.help(&format!("{}: {}", help, suggestion.as_help(path_str)));
2307 /// Report a link from a public item to a private one.
2308 fn privacy_error(cx: &DocContext<'_>, diag_info: &DiagnosticInfo<'_>, path_str: &str) {
2310 let item_name = match diag_info.item.name {
2315 None => "<unknown>",
2318 format!("public documentation for `{}` links to private item `{}`", item_name, path_str);
2320 report_diagnostic(cx.tcx, PRIVATE_INTRA_DOC_LINKS, &msg, diag_info, |diag, sp| {
2321 if let Some(sp) = sp {
2322 diag.span_label(sp, "this item is private");
2325 let note_msg = if cx.render_options.document_private {
2326 "this link resolves only because you passed `--document-private-items`, but will break without"
2328 "this link will resolve properly if you pass `--document-private-items`"
2330 diag.note(note_msg);
2334 /// Given an enum variant's res, return the res of its enum and the associated fragment.
2336 cx: &DocContext<'_>,
2338 ) -> Result<(Res, Option<ItemFragment>), ErrorKind<'static>> {
2339 let parent = cx.tcx.parent(res.def_id(cx.tcx));
2340 let parent_def = Res::Def(DefKind::Enum, parent);
2341 let variant = cx.tcx.expect_variant_res(res.as_hir_res().unwrap());
2342 Ok((parent_def, Some(ItemFragment(FragmentKind::Variant, variant.def_id))))
2345 /// Resolve a primitive type or value.
2346 fn resolve_primitive(path_str: &str, ns: Namespace) -> Option<Res> {
2350 use PrimitiveType::*;
2351 let prim = match path_str {
2367 "bool" | "true" | "false" => Bool,
2368 "str" | "&str" => Str,
2369 // See #80181 for why these don't have symbols associated.
2374 "pointer" | "*const" | "*mut" => RawPointer,
2375 "reference" | "&" | "&mut" => Reference,
2377 "never" | "!" => Never,
2380 debug!("resolved primitives {:?}", prim);
2381 Some(Res::Primitive(prim))
2384 fn strip_generics_from_path(path_str: &str) -> Result<String, ResolutionFailure<'static>> {
2385 let mut stripped_segments = vec![];
2386 let mut path = path_str.chars().peekable();
2387 let mut segment = Vec::new();
2389 while let Some(chr) = path.next() {
2392 if path.next_if_eq(&':').is_some() {
2393 let stripped_segment =
2394 strip_generics_from_path_segment(mem::take(&mut segment))?;
2395 if !stripped_segment.is_empty() {
2396 stripped_segments.push(stripped_segment);
2399 return Err(ResolutionFailure::MalformedGenerics(
2400 MalformedGenerics::InvalidPathSeparator,
2409 return Err(ResolutionFailure::MalformedGenerics(
2410 MalformedGenerics::TooManyAngleBrackets,
2414 return Err(ResolutionFailure::MalformedGenerics(
2415 MalformedGenerics::EmptyAngleBrackets,
2421 while let Some(chr) = path.next_if(|c| *c != '>') {
2428 _ => segment.push(chr),
2430 trace!("raw segment: {:?}", segment);
2433 if !segment.is_empty() {
2434 let stripped_segment = strip_generics_from_path_segment(segment)?;
2435 if !stripped_segment.is_empty() {
2436 stripped_segments.push(stripped_segment);
2440 debug!("path_str: {:?}\nstripped segments: {:?}", path_str, &stripped_segments);
2442 let stripped_path = stripped_segments.join("::");
2444 if !stripped_path.is_empty() {
2447 Err(ResolutionFailure::MalformedGenerics(MalformedGenerics::MissingType))
2451 fn strip_generics_from_path_segment(
2453 ) -> Result<String, ResolutionFailure<'static>> {
2454 let mut stripped_segment = String::new();
2455 let mut param_depth = 0;
2457 let mut latest_generics_chunk = String::new();
2462 latest_generics_chunk.clear();
2463 } else if c == '>' {
2465 if latest_generics_chunk.contains(" as ") {
2466 // The segment tries to use fully-qualified syntax, which is currently unsupported.
2467 // Give a helpful error message instead of completely ignoring the angle brackets.
2468 return Err(ResolutionFailure::MalformedGenerics(
2469 MalformedGenerics::HasFullyQualifiedSyntax,
2473 if param_depth == 0 {
2474 stripped_segment.push(c);
2476 latest_generics_chunk.push(c);
2481 if param_depth == 0 {
2482 Ok(stripped_segment)
2484 // The segment has unbalanced angle brackets, e.g. `Vec<T` or `Vec<T>>`
2485 Err(ResolutionFailure::MalformedGenerics(MalformedGenerics::UnbalancedAngleBrackets))