1 // Copyright 2018 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 use rustc::lint as lint;
15 use rustc::hir::def::Def;
18 use syntax::ast::{self, Ident, NodeId};
19 use syntax::feature_gate::UnstableFeatures;
20 use syntax::symbol::Symbol;
21 use syntax_pos::{self, DUMMY_SP};
27 use html::markdown::markdown_links;
29 use passes::{look_for_tests, Pass};
31 pub const COLLECT_INTRA_DOC_LINKS: Pass =
32 Pass::early("collect-intra-doc-links", collect_intra_doc_links,
33 "reads a crate's documentation to resolve intra-doc-links");
35 pub fn collect_intra_doc_links(krate: Crate, cx: &DocContext) -> Crate {
36 if !UnstableFeatures::from_environment().is_nightly_build() {
39 let mut coll = LinkCollector::new(cx);
41 coll.fold_crate(krate)
47 /// can be either value or type, not a macro
51 /// values, functions, consts, statics, everything in the value namespace
53 /// types, traits, everything in the type namespace
57 struct LinkCollector<'a, 'tcx: 'a, 'rcx: 'a, 'cstore: 'rcx> {
58 cx: &'a DocContext<'a, 'tcx, 'rcx, 'cstore>,
60 is_nightly_build: bool,
63 impl<'a, 'tcx, 'rcx, 'cstore> LinkCollector<'a, 'tcx, 'rcx, 'cstore> {
64 fn new(cx: &'a DocContext<'a, 'tcx, 'rcx, 'cstore>) -> Self {
68 is_nightly_build: UnstableFeatures::from_environment().is_nightly_build(),
72 /// Resolve a given string as a path, along with whether or not it is
73 /// in the value namespace. Also returns an optional URL fragment in the case
74 /// of variants and methods
78 current_item: &Option<String>,
79 parent_id: Option<NodeId>)
80 -> Result<(Def, Option<String>), ()>
84 // In case we're in a module, try to resolve the relative
86 if let Some(id) = parent_id.or(self.mod_ids.last().cloned()) {
87 // FIXME: `with_scope` requires the NodeId of a module
88 let result = cx.resolver.borrow_mut()
91 resolver.resolve_str_path_error(DUMMY_SP,
95 if let Ok(result) = result {
96 // In case this is a trait item, skip the
97 // early return and try looking for the trait
98 let value = match result.def {
99 Def::Method(_) | Def::AssociatedConst(_) => true,
100 Def::AssociatedTy(_) => false,
101 Def::Variant(_) => return handle_variant(cx, result.def),
102 // not a trait item, just return what we found
103 _ => return Ok((result.def, None))
109 } else if let Some(prim) = is_primitive(path_str, is_val) {
110 return Ok((prim, Some(path_str.to_owned())))
112 // If resolution failed, it may still be a method
113 // because methods are not handled by the resolver
114 // If so, bail when we're not looking for a value
120 // Try looking for methods and associated items
121 let mut split = path_str.rsplitn(2, "::");
122 let item_name = if let Some(first) = split.next() {
128 let mut path = if let Some(second) = split.next() {
134 if path == "self" || path == "Self" {
135 if let Some(name) = current_item.as_ref() {
140 // FIXME: `with_scope` requires the NodeId of a module
141 let ty = cx.resolver.borrow_mut()
144 resolver.resolve_str_path_error(DUMMY_SP, &path, false)
147 Def::Struct(did) | Def::Union(did) | Def::Enum(did) | Def::TyAlias(did) => {
148 let item = cx.tcx.inherent_impls(did)
150 .flat_map(|imp| cx.tcx.associated_items(*imp))
151 .find(|item| item.ident.name == item_name);
152 if let Some(item) = item {
153 let out = match item.kind {
154 ty::AssociatedKind::Method if is_val => "method",
155 ty::AssociatedKind::Const if is_val => "associatedconstant",
158 Ok((ty.def, Some(format!("{}.{}", out, item_name))))
160 match cx.tcx.type_of(did).sty {
162 if let Some(item) = if def.is_enum() {
163 def.all_fields().find(|item| item.ident.name == item_name)
165 def.non_enum_variant()
168 .find(|item| item.ident.name == item_name)
171 Some(format!("{}.{}",
187 let item = cx.tcx.associated_item_def_ids(did).iter()
188 .map(|item| cx.tcx.associated_item(*item))
189 .find(|item| item.ident.name == item_name);
190 if let Some(item) = item {
191 let kind = match item.kind {
192 ty::AssociatedKind::Const if is_val => "associatedconstant",
193 ty::AssociatedKind::Type if !is_val => "associatedtype",
194 ty::AssociatedKind::Method if is_val => {
195 if item.defaultness.has_value() {
204 Ok((ty.def, Some(format!("{}.{}", kind, item_name))))
217 impl<'a, 'tcx, 'rcx, 'cstore> DocFolder for LinkCollector<'a, 'tcx, 'rcx, 'cstore> {
218 fn fold_item(&mut self, mut item: Item) -> Option<Item> {
219 let item_node_id = if item.is_mod() {
220 if let Some(id) = self.cx.tcx.hir.as_local_node_id(item.def_id) {
223 debug!("attempting to fold on a non-local item: {:?}", item);
224 return self.fold_item_recur(item);
230 // FIXME: get the resolver to work with non-local resolve scopes
231 let parent_node = self.cx.as_local_node_id(item.def_id).and_then(|node_id| {
232 // FIXME: this fails hard for impls in non-module scope, but is necessary for the
233 // current resolve() implementation
234 match self.cx.tcx.hir.get_module_parent_node(node_id) {
235 id if id != node_id => Some(id),
240 if parent_node.is_some() {
241 debug!("got parent node for {} {:?}, id {:?}", item.type_(), item.name, item.def_id);
244 let current_item = match item.inner {
246 if item.attrs.inner_docs {
247 if item_node_id.unwrap() != NodeId::from_u32(0) {
253 match parent_node.or(self.mod_ids.last().cloned()) {
254 Some(parent) if parent != NodeId::from_u32(0) => {
255 //FIXME: can we pull the parent module's name from elsewhere?
256 Some(self.cx.tcx.hir.name(parent).to_string())
262 ImplItem(Impl { ref for_, .. }) => {
263 for_.def_id().map(|did| self.cx.tcx.item_name(did).to_string())
265 // we don't display docs on `extern crate` items anyway, so don't process them
266 ExternCrateItem(..) => return self.fold_item_recur(item),
267 ImportItem(Import::Simple(ref name, ..)) => Some(name.clone()),
268 MacroItem(..) => None,
269 _ => item.name.clone(),
272 if item.is_mod() && item.attrs.inner_docs {
273 self.mod_ids.push(item_node_id.unwrap());
277 let dox = item.attrs.collapsed_doc_value().unwrap_or_else(String::new);
279 look_for_tests(&cx, &dox, &item, true);
281 if !self.is_nightly_build {
285 for (ori_link, link_range) in markdown_links(&dox) {
286 // bail early for real links
287 if ori_link.contains('/') {
290 let link = ori_link.replace("`", "");
291 let (def, fragment) = {
292 let mut kind = PathKind::Unknown;
293 let path_str = if let Some(prefix) =
294 ["struct@", "enum@", "type@",
295 "trait@", "union@"].iter()
296 .find(|p| link.starts_with(**p)) {
297 kind = PathKind::Type;
298 link.trim_left_matches(prefix)
299 } else if let Some(prefix) =
300 ["const@", "static@",
301 "value@", "function@", "mod@",
302 "fn@", "module@", "method@"]
303 .iter().find(|p| link.starts_with(**p)) {
304 kind = PathKind::Value;
305 link.trim_left_matches(prefix)
306 } else if link.ends_with("()") {
307 kind = PathKind::Value;
308 link.trim_right_matches("()")
309 } else if link.starts_with("macro@") {
310 kind = PathKind::Macro;
311 link.trim_left_matches("macro@")
312 } else if link.ends_with('!') {
313 kind = PathKind::Macro;
314 link.trim_right_matches('!')
319 if path_str.contains(|ch: char| !(ch.is_alphanumeric() ||
320 ch == ':' || ch == '_')) {
326 if let Ok(def) = self.resolve(path_str, true, ¤t_item, parent_node) {
329 resolution_failure(cx, &item.attrs, path_str, &dox, link_range);
330 // this could just be a normal link or a broken link
331 // we could potentially check if something is
332 // "intra-doc-link-like" and warn in that case
337 if let Ok(def) = self.resolve(path_str, false, ¤t_item, parent_node) {
340 resolution_failure(cx, &item.attrs, path_str, &dox, link_range);
341 // this could just be a normal link
345 PathKind::Unknown => {
347 if let Some(macro_def) = macro_resolve(cx, path_str) {
348 if let Ok(type_def) =
349 self.resolve(path_str, false, ¤t_item, parent_node)
351 let (type_kind, article, type_disambig)
352 = type_ns_kind(type_def.0, path_str);
353 ambiguity_error(cx, &item.attrs, path_str,
354 article, type_kind, &type_disambig,
355 "a", "macro", &format!("macro@{}", path_str));
357 } else if let Ok(value_def) =
358 self.resolve(path_str, true, ¤t_item, parent_node)
360 let (value_kind, value_disambig)
361 = value_ns_kind(value_def.0, path_str)
362 .expect("struct and mod cases should have been \
363 caught in previous branch");
364 ambiguity_error(cx, &item.attrs, path_str,
365 "a", value_kind, &value_disambig,
366 "a", "macro", &format!("macro@{}", path_str));
369 } else if let Ok(type_def) =
370 self.resolve(path_str, false, ¤t_item, parent_node)
372 // It is imperative we search for not-a-value first
373 // Otherwise we will find struct ctors for when we are looking
374 // for structs, and the link won't work.
375 // if there is something in both namespaces
376 if let Ok(value_def) =
377 self.resolve(path_str, true, ¤t_item, parent_node)
379 let kind = value_ns_kind(value_def.0, path_str);
380 if let Some((value_kind, value_disambig)) = kind {
381 let (type_kind, article, type_disambig)
382 = type_ns_kind(type_def.0, path_str);
383 ambiguity_error(cx, &item.attrs, path_str,
384 article, type_kind, &type_disambig,
385 "a", value_kind, &value_disambig);
390 } else if let Ok(value_def) =
391 self.resolve(path_str, true, ¤t_item, parent_node)
395 resolution_failure(cx, &item.attrs, path_str, &dox, link_range);
396 // this could just be a normal link
401 if let Some(def) = macro_resolve(cx, path_str) {
404 resolution_failure(cx, &item.attrs, path_str, &dox, link_range);
411 if let Def::PrimTy(_) = def {
412 item.attrs.links.push((ori_link, None, fragment));
414 let id = register_def(cx, def);
415 item.attrs.links.push((ori_link, Some(id), fragment));
419 if item.is_mod() && !item.attrs.inner_docs {
420 self.mod_ids.push(item_node_id.unwrap());
424 let ret = self.fold_item_recur(item);
430 self.fold_item_recur(item)
435 /// Resolve a string as a macro
436 fn macro_resolve(cx: &DocContext, path_str: &str) -> Option<Def> {
437 use syntax::ext::base::{MacroKind, SyntaxExtension};
438 let segment = ast::PathSegment::from_ident(Ident::from_str(path_str));
439 let path = ast::Path { segments: vec![segment], span: DUMMY_SP };
440 let mut resolver = cx.resolver.borrow_mut();
441 let parent_scope = resolver.dummy_parent_scope();
442 if let Ok(def) = resolver.resolve_macro_to_def_inner(&path, MacroKind::Bang,
443 &parent_scope, false, false) {
444 if let SyntaxExtension::DeclMacro { .. } = *resolver.get_macro(def) {
448 if let Some(def) = resolver.all_macros.get(&Symbol::intern(path_str)) {
454 pub fn span_of_attrs(attrs: &Attributes) -> syntax_pos::Span {
455 if attrs.doc_strings.is_empty() {
458 let start = attrs.doc_strings[0].span();
459 let end = attrs.doc_strings.last().expect("No doc strings provided").span();
463 fn resolution_failure(
468 link_range: Option<Range<usize>>,
470 let sp = span_of_attrs(attrs);
471 let msg = format!("`[{}]` cannot be resolved, ignoring it...", path_str);
473 let code_dox = sp.to_src(cx);
475 let doc_comment_padding = 3;
476 let mut diag = if let Some(link_range) = link_range {
477 // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
480 // last_new_line_offset
483 if dox.lines().count() == code_dox.lines().count() {
484 let line_offset = dox[..link_range.start].lines().count();
485 // The span starts in the `///`, so we don't have to account for the leading whitespace
486 let code_dox_len = if line_offset <= 1 {
490 doc_comment_padding +
491 // Each subsequent leading whitespace and `///`
492 code_dox.lines().skip(1).take(line_offset - 1).fold(0, |sum, line| {
493 sum + doc_comment_padding + line.len() - line.trim_start().len()
497 // Extract the specific span
498 let sp = sp.from_inner_byte_pos(
499 link_range.start + code_dox_len,
500 link_range.end + code_dox_len,
503 diag = cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
507 diag.span_label(sp, "cannot be resolved, ignoring");
509 diag = cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
514 let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
515 let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
517 // Print the line containing the `link_range` and manually mark it with '^'s
519 "the link appears in this line:\n\n{line}\n\
520 {indicator: <before$}{indicator:^<found$}",
523 before=link_range.start - last_new_line_offset,
524 found=link_range.len(),
529 cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
534 diag.help("to escape `[` and `]` characters, just add '\\' before them like \
539 fn ambiguity_error(cx: &DocContext, attrs: &Attributes,
541 article1: &str, kind1: &str, disambig1: &str,
542 article2: &str, kind2: &str, disambig2: &str) {
543 let sp = span_of_attrs(attrs);
545 .struct_span_warn(sp,
546 &format!("`{}` is both {} {} and {} {}",
547 path_str, article1, kind1,
549 .help(&format!("try `{}` if you want to select the {}, \
550 or `{}` if you want to \
552 disambig1, kind1, disambig2,
557 /// Given a def, returns its name and disambiguator
558 /// for a value namespace
560 /// Returns None for things which cannot be ambiguous since
561 /// they exist in both namespaces (structs and modules)
562 fn value_ns_kind(def: Def, path_str: &str) -> Option<(&'static str, String)> {
564 // structs, variants, and mods exist in both namespaces. skip them
565 Def::StructCtor(..) | Def::Mod(..) | Def::Variant(..) |
566 Def::VariantCtor(..) | Def::SelfCtor(..)
569 => Some(("function", format!("{}()", path_str))),
571 => Some(("method", format!("{}()", path_str))),
573 => Some(("const", format!("const@{}", path_str))),
575 => Some(("static", format!("static@{}", path_str))),
576 _ => Some(("value", format!("value@{}", path_str))),
580 /// Given a def, returns its name, the article to be used, and a disambiguator
581 /// for the type namespace
582 fn type_ns_kind(def: Def, path_str: &str) -> (&'static str, &'static str, String) {
583 let (kind, article) = match def {
584 // we can still have non-tuple structs
585 Def::Struct(..) => ("struct", "a"),
586 Def::Enum(..) => ("enum", "an"),
587 Def::Trait(..) => ("trait", "a"),
588 Def::Union(..) => ("union", "a"),
591 (kind, article, format!("{}@{}", kind, path_str))
594 /// Given an enum variant's def, return the def of its enum and the associated fragment
595 fn handle_variant(cx: &DocContext, def: Def) -> Result<(Def, Option<String>), ()> {
596 use rustc::ty::DefIdTree;
598 let parent = if let Some(parent) = cx.tcx.parent(def.def_id()) {
603 let parent_def = Def::Enum(parent);
604 let variant = cx.tcx.expect_variant_def(def);
605 Ok((parent_def, Some(format!("{}.v", variant.name))))
608 const PRIMITIVES: &[(&str, Def)] = &[
609 ("u8", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U8))),
610 ("u16", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U16))),
611 ("u32", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U32))),
612 ("u64", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U64))),
613 ("u128", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U128))),
614 ("usize", Def::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::Usize))),
615 ("i8", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I8))),
616 ("i16", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I16))),
617 ("i32", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I32))),
618 ("i64", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I64))),
619 ("i128", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I128))),
620 ("isize", Def::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::Isize))),
621 ("f32", Def::PrimTy(hir::PrimTy::Float(syntax::ast::FloatTy::F32))),
622 ("f64", Def::PrimTy(hir::PrimTy::Float(syntax::ast::FloatTy::F64))),
623 ("str", Def::PrimTy(hir::PrimTy::Str)),
624 ("bool", Def::PrimTy(hir::PrimTy::Bool)),
625 ("char", Def::PrimTy(hir::PrimTy::Char)),
628 fn is_primitive(path_str: &str, is_val: bool) -> Option<Def> {
632 PRIMITIVES.iter().find(|x| x.0 == path_str).map(|x| x.1)