1 //! Rustdoc's HTML rendering module.
3 //! This modules contains the bulk of the logic necessary for rendering a
4 //! rustdoc `clean::Crate` instance to a set of static HTML pages. This
5 //! rendering process is largely driven by the `format!` syntax extension to
6 //! perform all I/O into files and streams.
8 //! The rendering process is largely driven by the `Context` and `Cache`
9 //! structures. The cache is pre-populated by crawling the crate in question,
10 //! and then it is shared among the various rendering threads. The cache is meant
11 //! to be a fairly large structure not implementing `Clone` (because it's shared
12 //! among threads). The context, however, should be a lightweight structure. This
13 //! is cloned per-thread and contains information about what is currently being
16 //! In order to speed up rendering (mostly because of markdown rendering), the
17 //! rendering process has been parallelized. This parallelization is only
18 //! exposed through the `crate` method on the context, and then also from the
19 //! fact that the shared cache is stored in TLS (and must be accessed as such).
21 //! In addition to rendering the crate itself, this module is also responsible
22 //! for creating the corresponding search index and source file renderings.
23 //! These threads are not parallelized (they haven't been a bottleneck yet), and
24 //! both occur before the crate is rendered.
26 pub(crate) mod search_index;
36 pub(crate) use self::context::*;
37 pub(crate) use self::span_map::{collect_spans_and_sources, LinkFromSrc};
39 use std::collections::VecDeque;
40 use std::default::Default;
43 use std::iter::Peekable;
44 use std::path::PathBuf;
46 use std::string::ToString;
48 use rustc_ast_pretty::pprust;
49 use rustc_attr::{ConstStability, Deprecation, StabilityLevel};
50 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
51 use rustc_hir::def::CtorKind;
52 use rustc_hir::def_id::DefId;
53 use rustc_hir::Mutability;
54 use rustc_middle::middle::stability;
56 use rustc_middle::ty::TyCtxt;
58 symbol::{kw, sym, Symbol},
59 BytePos, FileName, RealFileName,
61 use serde::ser::SerializeSeq;
62 use serde::{Serialize, Serializer};
64 use crate::clean::{self, ItemId, RenderedLink, SelfTy};
65 use crate::error::Error;
66 use crate::formats::cache::Cache;
67 use crate::formats::item_type::ItemType;
68 use crate::formats::{AssocItemRender, Impl, RenderMode};
69 use crate::html::escape::Escape;
70 use crate::html::format::{
71 href, join_with_double_colon, print_abi_with_space, print_constness_with_space,
72 print_default_space, print_generic_bounds, print_where_clause, Buffer, HrefError,
75 use crate::html::highlight;
76 use crate::html::markdown::{HeadingOffset, IdMap, Markdown, MarkdownHtml, MarkdownSummaryLine};
77 use crate::html::sources;
78 use crate::html::static_files::SCRAPE_EXAMPLES_HELP_MD;
79 use crate::scrape_examples::{CallData, CallLocation};
81 use crate::DOC_RUST_LANG_ORG_CHANNEL;
83 /// A pair of name and its optional document.
84 pub(crate) type NameDoc = (String, Option<String>);
86 pub(crate) fn ensure_trailing_slash(v: &str) -> impl fmt::Display + '_ {
87 crate::html::format::display_fn(move |f| {
88 if !v.ends_with('/') && !v.is_empty() { write!(f, "{}/", v) } else { f.write_str(v) }
92 // Helper structs for rendering items/sidebars and carrying along contextual
95 /// Struct representing one entry in the JS search index. These are all emitted
96 /// by hand to a large JS file at the end of cache-creation.
98 pub(crate) struct IndexItem {
99 pub(crate) ty: ItemType,
100 pub(crate) name: String,
101 pub(crate) path: String,
102 pub(crate) desc: String,
103 pub(crate) parent: Option<DefId>,
104 pub(crate) parent_idx: Option<usize>,
105 pub(crate) search_type: Option<IndexItemFunctionType>,
106 pub(crate) aliases: Box<[Symbol]>,
109 /// A type used for the search index.
111 pub(crate) struct RenderType {
112 name: Option<String>,
113 generics: Option<Vec<TypeWithKind>>,
116 /// Full type of functions/methods in the search index.
118 pub(crate) struct IndexItemFunctionType {
119 inputs: Vec<TypeWithKind>,
120 output: Vec<TypeWithKind>,
123 impl Serialize for IndexItemFunctionType {
124 fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
128 // If we couldn't figure out a type, just write `null`.
129 let has_missing = self.inputs.iter().chain(self.output.iter()).any(|i| i.ty.name.is_none());
131 serializer.serialize_none()
133 let mut seq = serializer.serialize_seq(None)?;
134 seq.serialize_element(&self.inputs)?;
135 match self.output.as_slice() {
137 [one] => seq.serialize_element(one)?,
138 all => seq.serialize_element(all)?,
146 pub(crate) struct TypeWithKind {
151 impl From<(RenderType, ItemType)> for TypeWithKind {
152 fn from(x: (RenderType, ItemType)) -> TypeWithKind {
153 TypeWithKind { ty: x.0, kind: x.1 }
157 impl Serialize for TypeWithKind {
158 fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
162 let mut seq = serializer.serialize_seq(None)?;
163 seq.serialize_element(&self.ty.name)?;
164 seq.serialize_element(&self.kind)?;
165 if let Some(generics) = &self.ty.generics {
166 seq.serialize_element(generics)?;
172 #[derive(Debug, Clone)]
173 pub(crate) struct StylePath {
174 /// The path to the theme
175 pub(crate) path: PathBuf,
179 pub(crate) fn basename(&self) -> Result<String, Error> {
180 Ok(try_none!(try_none!(self.path.file_stem(), &self.path).to_str(), &self.path).to_string())
184 fn write_srclink(cx: &Context<'_>, item: &clean::Item, buf: &mut Buffer) {
185 if let Some(l) = cx.src_href(item) {
186 write!(buf, "<a class=\"srclink\" href=\"{}\">source</a>", l)
190 #[derive(Debug, Eq, PartialEq, Hash)]
197 fn new(mut url: String, name: String) -> ItemEntry {
198 while url.starts_with('/') {
201 ItemEntry { url, name }
206 pub(crate) fn print(&self) -> impl fmt::Display + '_ {
207 crate::html::format::display_fn(move |f| {
208 write!(f, "<a href=\"{}\">{}</a>", self.url, Escape(&self.name))
213 impl PartialOrd for ItemEntry {
214 fn partial_cmp(&self, other: &ItemEntry) -> Option<::std::cmp::Ordering> {
215 Some(self.cmp(other))
219 impl Ord for ItemEntry {
220 fn cmp(&self, other: &ItemEntry) -> ::std::cmp::Ordering {
221 self.name.cmp(&other.name)
227 structs: FxHashSet<ItemEntry>,
228 enums: FxHashSet<ItemEntry>,
229 unions: FxHashSet<ItemEntry>,
230 primitives: FxHashSet<ItemEntry>,
231 traits: FxHashSet<ItemEntry>,
232 macros: FxHashSet<ItemEntry>,
233 functions: FxHashSet<ItemEntry>,
234 typedefs: FxHashSet<ItemEntry>,
235 opaque_tys: FxHashSet<ItemEntry>,
236 statics: FxHashSet<ItemEntry>,
237 constants: FxHashSet<ItemEntry>,
238 attributes: FxHashSet<ItemEntry>,
239 derives: FxHashSet<ItemEntry>,
240 trait_aliases: FxHashSet<ItemEntry>,
244 fn new() -> AllTypes {
245 let new_set = |cap| FxHashSet::with_capacity_and_hasher(cap, Default::default());
247 structs: new_set(100),
249 unions: new_set(100),
250 primitives: new_set(26),
251 traits: new_set(100),
252 macros: new_set(100),
253 functions: new_set(100),
254 typedefs: new_set(100),
255 opaque_tys: new_set(100),
256 statics: new_set(100),
257 constants: new_set(100),
258 attributes: new_set(100),
259 derives: new_set(100),
260 trait_aliases: new_set(100),
264 fn append(&mut self, item_name: String, item_type: &ItemType) {
265 let mut url: Vec<_> = item_name.split("::").skip(1).collect();
266 if let Some(name) = url.pop() {
267 let new_url = format!("{}/{}.{}.html", url.join("/"), item_type, name);
269 let name = url.join("::");
271 ItemType::Struct => self.structs.insert(ItemEntry::new(new_url, name)),
272 ItemType::Enum => self.enums.insert(ItemEntry::new(new_url, name)),
273 ItemType::Union => self.unions.insert(ItemEntry::new(new_url, name)),
274 ItemType::Primitive => self.primitives.insert(ItemEntry::new(new_url, name)),
275 ItemType::Trait => self.traits.insert(ItemEntry::new(new_url, name)),
276 ItemType::Macro => self.macros.insert(ItemEntry::new(new_url, name)),
277 ItemType::Function => self.functions.insert(ItemEntry::new(new_url, name)),
278 ItemType::Typedef => self.typedefs.insert(ItemEntry::new(new_url, name)),
279 ItemType::OpaqueTy => self.opaque_tys.insert(ItemEntry::new(new_url, name)),
280 ItemType::Static => self.statics.insert(ItemEntry::new(new_url, name)),
281 ItemType::Constant => self.constants.insert(ItemEntry::new(new_url, name)),
282 ItemType::ProcAttribute => self.attributes.insert(ItemEntry::new(new_url, name)),
283 ItemType::ProcDerive => self.derives.insert(ItemEntry::new(new_url, name)),
284 ItemType::TraitAlias => self.trait_aliases.insert(ItemEntry::new(new_url, name)),
292 fn print(self, f: &mut Buffer) {
293 fn print_entries(f: &mut Buffer, e: &FxHashSet<ItemEntry>, title: &str, class: &str) {
295 let mut e: Vec<&ItemEntry> = e.iter().collect();
299 "<h3 id=\"{}\">{}</h3><ul class=\"{} docblock\">",
300 title.replace(' ', "-"), // IDs cannot contain whitespaces.
306 write!(f, "<li>{}</li>", s.print());
309 f.write_str("</ul>");
315 <span class=\"in-band\">List of all items</span>\
318 // Note: print_entries does not escape the title, because we know the current set of titles
319 // doesn't require escaping.
320 print_entries(f, &self.structs, "Structs", "structs");
321 print_entries(f, &self.enums, "Enums", "enums");
322 print_entries(f, &self.unions, "Unions", "unions");
323 print_entries(f, &self.primitives, "Primitives", "primitives");
324 print_entries(f, &self.traits, "Traits", "traits");
325 print_entries(f, &self.macros, "Macros", "macros");
326 print_entries(f, &self.attributes, "Attribute Macros", "attributes");
327 print_entries(f, &self.derives, "Derive Macros", "derives");
328 print_entries(f, &self.functions, "Functions", "functions");
329 print_entries(f, &self.typedefs, "Typedefs", "typedefs");
330 print_entries(f, &self.trait_aliases, "Trait Aliases", "trait-aliases");
331 print_entries(f, &self.opaque_tys, "Opaque Types", "opaque-types");
332 print_entries(f, &self.statics, "Statics", "statics");
333 print_entries(f, &self.constants, "Constants", "constants")
337 fn scrape_examples_help(shared: &SharedContext<'_>) -> String {
338 let mut content = SCRAPE_EXAMPLES_HELP_MD.to_owned();
339 content.push_str(&format!(
340 "## More information\n\n\
341 If you want more information about this feature, please read the [corresponding chapter in the Rustdoc book]({}/rustdoc/scraped-examples.html).",
342 DOC_RUST_LANG_ORG_CHANNEL));
344 let mut ids = IdMap::default();
346 "<div class=\"main-heading\">\
348 <span class=\"in-band\">About scraped examples</span>\
356 error_codes: shared.codes,
357 edition: shared.edition(),
358 playground: &shared.playground,
359 heading_offset: HeadingOffset::H1
369 parent: Option<&clean::Item>,
370 heading_offset: HeadingOffset,
372 if let Some(ref name) = item.name {
373 info!("Documenting {}", name);
375 document_item_info(w, cx, item, parent);
376 if parent.is_none() {
377 document_full_collapsible(w, item, cx, heading_offset);
379 document_full(w, item, cx, heading_offset);
383 /// Render md_text as markdown.
388 links: Vec<RenderedLink>,
389 heading_offset: HeadingOffset,
391 let mut ids = cx.id_map.borrow_mut();
394 "<div class=\"docblock\">{}</div>",
399 error_codes: cx.shared.codes,
400 edition: cx.shared.edition(),
401 playground: &cx.shared.playground,
408 /// Writes a documentation block containing only the first paragraph of the documentation. If the
409 /// docs are longer, a "Read more" link is appended to the end.
414 link: AssocItemLink<'_>,
415 parent: &clean::Item,
418 document_item_info(w, cx, item, Some(parent));
422 if let Some(s) = item.doc_value() {
423 let mut summary_html = MarkdownSummaryLine(&s, &item.links(cx)).into_string();
425 if s.contains('\n') {
426 let link = format!(r#" <a{}>Read more</a>"#, assoc_href_attr(item, link, cx));
428 if let Some(idx) = summary_html.rfind("</p>") {
429 summary_html.insert_str(idx, &link);
431 summary_html.push_str(&link);
435 write!(w, "<div class='docblock'>{}</div>", summary_html,);
439 fn document_full_collapsible(
443 heading_offset: HeadingOffset,
445 document_full_inner(w, item, cx, true, heading_offset);
452 heading_offset: HeadingOffset,
454 document_full_inner(w, item, cx, false, heading_offset);
457 fn document_full_inner(
461 is_collapsible: bool,
462 heading_offset: HeadingOffset,
464 if let Some(s) = item.collapsed_doc_value() {
465 debug!("Doc block: =====\n{}\n=====", s);
468 "<details class=\"rustdoc-toggle top-doc\" open>\
469 <summary class=\"hideme\">\
470 <span>Expand description</span>\
473 render_markdown(w, cx, &s, item.links(cx), heading_offset);
474 w.write_str("</details>");
476 render_markdown(w, cx, &s, item.links(cx), heading_offset);
480 let kind = match &*item.kind {
481 clean::ItemKind::StrippedItem(box kind) | kind => kind,
484 if let clean::ItemKind::FunctionItem(..) | clean::ItemKind::MethodItem(..) = kind {
485 render_call_locations(w, cx, item);
489 /// Add extra information about an item such as:
493 /// * Required features (through the `doc_cfg` feature)
494 fn document_item_info(
498 parent: Option<&clean::Item>,
500 let item_infos = short_item_info(item, cx, parent);
501 if !item_infos.is_empty() {
502 w.write_str("<span class=\"item-info\">");
503 for info in item_infos {
506 w.write_str("</span>");
510 fn portability(item: &clean::Item, parent: Option<&clean::Item>) -> Option<String> {
511 let cfg = match (&item.cfg, parent.and_then(|p| p.cfg.as_ref())) {
512 (Some(cfg), Some(parent_cfg)) => cfg.simplify_with(parent_cfg),
513 (cfg, _) => cfg.as_deref().cloned(),
516 debug!("Portability {:?} - {:?} = {:?}", item.cfg, parent.and_then(|p| p.cfg.as_ref()), cfg);
518 Some(format!("<div class=\"stab portability\">{}</div>", cfg?.render_long_html()))
521 /// Render the stability, deprecation and portability information that is displayed at the top of
522 /// the item's documentation.
526 parent: Option<&clean::Item>,
528 let mut extra_info = vec![];
529 let error_codes = cx.shared.codes;
531 if let Some(depr @ Deprecation { note, since, is_since_rustc_version: _, suggestion: _ }) =
532 item.deprecation(cx.tcx())
534 // We display deprecation messages for #[deprecated], but only display
535 // the future-deprecation messages for rustc versions.
536 let mut message = if let Some(since) = since {
537 let since = since.as_str();
538 if !stability::deprecation_in_effect(&depr) {
540 String::from("Deprecating in a future Rust version")
542 format!("Deprecating in {}", Escape(since))
545 format!("Deprecated since {}", Escape(since))
548 String::from("Deprecated")
551 if let Some(note) = note {
552 let note = note.as_str();
553 let mut ids = cx.id_map.borrow_mut();
554 let html = MarkdownHtml(
559 &cx.shared.playground,
561 message.push_str(&format!(": {}", html.into_string()));
563 extra_info.push(format!(
564 "<div class=\"stab deprecated\"><span class=\"emoji\">👎</span> {}</div>",
569 // Render unstable items. But don't render "rustc_private" crates (internal compiler crates).
570 // Those crates are permanently unstable so it makes no sense to render "unstable" everywhere.
571 if let Some((StabilityLevel::Unstable { reason: _, issue, .. }, feature)) = item
574 .filter(|stab| stab.feature != sym::rustc_private)
575 .map(|stab| (stab.level, stab.feature))
578 "<span class=\"emoji\">🔬</span> This is a nightly-only experimental API.".to_owned();
580 let mut feature = format!("<code>{}</code>", Escape(feature.as_str()));
581 if let (Some(url), Some(issue)) = (&cx.shared.issue_tracker_base_url, issue) {
582 feature.push_str(&format!(
583 " <a href=\"{url}{issue}\">#{issue}</a>",
589 message.push_str(&format!(" ({})", feature));
591 extra_info.push(format!("<div class=\"stab unstable\">{}</div>", message));
594 if let Some(portability) = portability(item, parent) {
595 extra_info.push(portability);
601 // Render the list of items inside one of the sections "Trait Implementations",
602 // "Auto Trait Implementations," "Blanket Trait Implementations" (on struct/enum pages).
607 containing_item: &clean::Item,
608 toggle_open_by_default: bool,
611 let mut rendered_impls = impls
614 let did = i.trait_did().unwrap();
615 let provided_trait_methods = i.inner_impl().provided_trait_methods(tcx);
616 let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_trait_methods);
617 let mut buffer = if w.is_for_html() { Buffer::html() } else { Buffer::new() };
627 ImplRenderingParameters {
629 is_on_foreign_type: false,
630 show_default_items: true,
631 show_non_assoc_items: true,
632 toggle_open_by_default,
637 .collect::<Vec<_>>();
638 rendered_impls.sort();
639 w.write_str(&rendered_impls.join(""));
642 /// Build a (possibly empty) `href` attribute (a key-value pair) for the given associated item.
643 fn assoc_href_attr(it: &clean::Item, link: AssocItemLink<'_>, cx: &Context<'_>) -> String {
644 let name = it.name.unwrap();
645 let item_type = it.type_();
647 let href = match link {
648 AssocItemLink::Anchor(Some(ref id)) => Some(format!("#{}", id)),
649 AssocItemLink::Anchor(None) => Some(format!("#{}.{}", item_type, name)),
650 AssocItemLink::GotoSource(did, provided_methods) => {
651 // We're creating a link from the implementation of an associated item to its
652 // declaration in the trait declaration.
653 let item_type = match item_type {
654 // For historical but not technical reasons, the item type of methods in
655 // trait declarations depends on whether the method is required (`TyMethod`) or
656 // provided (`Method`).
657 ItemType::Method | ItemType::TyMethod => {
658 if provided_methods.contains(&name) {
664 // For associated types and constants, no such distinction exists.
665 item_type => item_type,
668 match href(did.expect_def_id(), cx) {
669 Ok((url, ..)) => Some(format!("{}#{}.{}", url, item_type, name)),
670 // The link is broken since it points to an external crate that wasn't documented.
671 // Do not create any link in such case. This is better than falling back to a
672 // dummy anchor like `#{item_type}.{name}` representing the `id` of *this* impl item
673 // (that used to happen in older versions). Indeed, in most cases this dummy would
674 // coincide with the `id`. However, it would not always do so.
675 // In general, this dummy would be incorrect:
676 // If the type with the trait impl also had an inherent impl with an assoc. item of
677 // the *same* name as this impl item, the dummy would link to that one even though
678 // those two items are distinct!
679 // In this scenario, the actual `id` of this impl item would be
680 // `#{item_type}.{name}-{n}` for some number `n` (a disambiguator).
681 Err(HrefError::DocumentationNotBuilt) => None,
682 Err(_) => Some(format!("#{}.{}", item_type, name)),
687 // If there is no `href` for the reason explained above, simply do not render it which is valid:
688 // https://html.spec.whatwg.org/multipage/links.html#links-created-by-a-and-area-elements
689 href.map(|href| format!(" href=\"{}\"", href)).unwrap_or_default()
696 default: Option<&clean::ConstantKind>,
697 link: AssocItemLink<'_>,
703 "{extra}{vis}const <a{href} class=\"constant\">{name}</a>: {ty}",
705 vis = it.visibility.print_with_space(it.item_id, cx),
706 href = assoc_href_attr(it, link, cx),
707 name = it.name.as_ref().unwrap(),
710 if let Some(default) = default {
711 // FIXME: `.value()` uses `clean::utils::format_integer_with_underscore_sep` under the
712 // hood which adds noisy underscores and a type suffix to number literals.
713 // This hurts readability in this context especially when more complex expressions
714 // are involved and it doesn't add much of value.
715 // Find a way to print constants here without all that jazz.
716 write!(w, " = {}", default.value(cx.tcx()).unwrap_or_else(|| default.expr(cx.tcx())));
723 generics: &clean::Generics,
724 bounds: &[clean::GenericBound],
725 default: Option<&clean::Type>,
726 link: AssocItemLink<'_>,
732 "{indent}type <a{href} class=\"associatedtype\">{name}</a>{generics}",
733 indent = " ".repeat(indent),
734 href = assoc_href_attr(it, link, cx),
735 name = it.name.as_ref().unwrap(),
736 generics = generics.print(cx),
738 if !bounds.is_empty() {
739 write!(w, ": {}", print_generic_bounds(bounds, cx))
741 write!(w, "{}", print_where_clause(generics, cx, indent, false));
742 if let Some(default) = default {
743 write!(w, " = {}", default.print(cx))
752 link: AssocItemLink<'_>,
755 render_mode: RenderMode,
757 let header = meth.fn_header(cx.tcx()).expect("Trying to get header from a non-function item");
758 let name = meth.name.as_ref().unwrap();
759 let vis = meth.visibility.print_with_space(meth.item_id, cx).to_string();
760 // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
762 let constness = match render_mode {
763 RenderMode::Normal => {
764 print_constness_with_space(&header.constness, meth.const_stability(cx.tcx()))
766 RenderMode::ForDeref { .. } => "",
768 let asyncness = header.asyncness.print_with_space();
769 let unsafety = header.unsafety.print_with_space();
770 let defaultness = print_default_space(meth.is_default());
771 let abi = print_abi_with_space(header.abi).to_string();
772 let href = assoc_href_attr(meth, link, cx);
774 // NOTE: `{:#}` does not print HTML formatting, `{}` does. So `g.print` can't be reused between the length calculation and `write!`.
775 let generics_len = format!("{:#}", g.print(cx)).len();
776 let mut header_len = "fn ".len()
783 + name.as_str().len()
786 let (indent, indent_str, end_newline) = if parent == ItemType::Trait {
788 let indent_str = " ";
789 render_attributes_in_pre(w, meth, indent_str);
790 (4, indent_str, false)
792 render_attributes_in_code(w, meth);
795 w.reserve(header_len + "<a href=\"\" class=\"fnname\">{".len() + "</a>".len());
798 "{indent}{vis}{constness}{asyncness}{unsafety}{defaultness}{abi}fn <a{href} class=\"fnname\">{name}</a>\
799 {generics}{decl}{notable_traits}{where_clause}",
802 constness = constness,
803 asyncness = asyncness,
805 defaultness = defaultness,
809 generics = g.print(cx),
810 decl = d.full_print(header_len, indent, header.asyncness, cx),
811 notable_traits = notable_traits_decl(d, cx),
812 where_clause = print_where_clause(g, cx, indent, end_newline),
816 /// Writes a span containing the versions at which an item became stable and/or const-stable. For
817 /// example, if the item became stable at 1.0.0, and const-stable at 1.45.0, this function would
818 /// write a span containing "1.0.0 (const: 1.45.0)".
820 /// Returns `true` if a stability annotation was rendered.
822 /// Stability and const-stability are considered separately. If the item is unstable, no version
823 /// will be written. If the item is const-unstable, "const: unstable" will be appended to the
824 /// span, with a link to the tracking issue if present. If an item's stability or const-stability
825 /// version matches the version of its enclosing item, that version will be omitted.
827 /// Note that it is possible for an unstable function to be const-stable. In that case, the span
828 /// will include the const-stable version, but no stable version will be emitted, as a natural
829 /// consequence of the above rules.
830 fn render_stability_since_raw(
833 const_stability: Option<ConstStability>,
834 containing_ver: Option<Symbol>,
835 containing_const_ver: Option<Symbol>,
837 let stable_version = ver.filter(|inner| !inner.is_empty() && Some(*inner) != containing_ver);
839 let mut title = String::new();
840 let mut stability = String::new();
842 if let Some(ver) = stable_version {
843 stability.push_str(&ver.as_str());
844 title.push_str(&format!("Stable since Rust version {}", ver));
847 let const_title_and_stability = match const_stability {
848 Some(ConstStability { level: StabilityLevel::Stable { since }, .. })
849 if Some(since) != containing_const_ver =>
851 Some((format!("const since {}", since), format!("const: {}", since)))
853 Some(ConstStability { level: StabilityLevel::Unstable { issue, .. }, feature, .. }) => {
854 let unstable = if let Some(n) = issue {
856 r#"<a href="https://github.com/rust-lang/rust/issues/{}" title="Tracking issue for {}">unstable</a>"#,
860 String::from("unstable")
863 Some((String::from("const unstable"), format!("const: {}", unstable)))
868 if let Some((const_title, const_stability)) = const_title_and_stability {
869 if !title.is_empty() {
870 title.push_str(&format!(", {}", const_title));
872 title.push_str(&const_title);
875 if !stability.is_empty() {
876 stability.push_str(&format!(" ({})", const_stability));
878 stability.push_str(&const_stability);
882 if !stability.is_empty() {
883 write!(w, r#"<span class="since" title="{}">{}</span>"#, title, stability);
886 !stability.is_empty()
889 fn render_assoc_item(
892 link: AssocItemLink<'_>,
895 render_mode: RenderMode,
898 clean::StrippedItem(..) => {}
899 clean::TyMethodItem(m) => {
900 assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode)
902 clean::MethodItem(m, _) => {
903 assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode)
905 kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => assoc_const(
910 clean::TyAssocConstItem(_) => None,
911 clean::AssocConstItem(_, default) => Some(default),
915 if parent == ItemType::Trait { " " } else { "" },
918 clean::TyAssocTypeItem(ref generics, ref bounds) => assoc_type(
925 if parent == ItemType::Trait { 4 } else { 0 },
928 clean::AssocTypeItem(ref ty, ref bounds) => assoc_type(
933 Some(ty.item_type.as_ref().unwrap_or(&ty.type_)),
935 if parent == ItemType::Trait { 4 } else { 0 },
938 _ => panic!("render_assoc_item called on non-associated-item"),
942 const ALLOWED_ATTRIBUTES: &[Symbol] =
943 &[sym::export_name, sym::link_section, sym::no_mangle, sym::repr, sym::non_exhaustive];
945 fn attributes(it: &clean::Item) -> Vec<String> {
950 if ALLOWED_ATTRIBUTES.contains(&attr.name_or_empty()) {
952 pprust::attribute_to_string(attr)
964 // When an attribute is rendered inside a `<pre>` tag, it is formatted using
965 // a whitespace prefix and newline.
966 fn render_attributes_in_pre(w: &mut Buffer, it: &clean::Item, prefix: &str) {
967 for a in attributes(it) {
968 writeln!(w, "{}{}", prefix, a);
972 // When an attribute is rendered inside a <code> tag, it is formatted using
973 // a div to produce a newline after it.
974 fn render_attributes_in_code(w: &mut Buffer, it: &clean::Item) {
975 for a in attributes(it) {
976 write!(w, "<div class=\"code-attribute\">{}</div>", a);
980 #[derive(Copy, Clone)]
981 enum AssocItemLink<'a> {
982 Anchor(Option<&'a str>),
983 GotoSource(ItemId, &'a FxHashSet<Symbol>),
986 impl<'a> AssocItemLink<'a> {
987 fn anchor(&self, id: &'a str) -> Self {
989 AssocItemLink::Anchor(_) => AssocItemLink::Anchor(Some(id)),
995 fn render_assoc_items(
998 containing_item: &clean::Item,
1000 what: AssocItemRender<'_>,
1002 let mut derefs = FxHashSet::default();
1004 render_assoc_items_inner(w, cx, containing_item, it, what, &mut derefs)
1007 fn render_assoc_items_inner(
1010 containing_item: &clean::Item,
1012 what: AssocItemRender<'_>,
1013 derefs: &mut FxHashSet<DefId>,
1015 info!("Documenting associated items of {:?}", containing_item.name);
1016 let cache = cx.cache();
1017 let Some(v) = cache.impls.get(&it) else { return };
1018 let (non_trait, traits): (Vec<_>, _) = v.iter().partition(|i| i.inner_impl().trait_.is_none());
1019 if !non_trait.is_empty() {
1020 let mut tmp_buf = Buffer::empty_from(w);
1021 let (render_mode, id) = match what {
1022 AssocItemRender::All => {
1024 "<h2 id=\"implementations\" class=\"small-section-header\">\
1026 <a href=\"#implementations\" class=\"anchor\"></a>\
1029 (RenderMode::Normal, "implementations-list".to_owned())
1031 AssocItemRender::DerefFor { trait_, type_, deref_mut_ } => {
1033 cx.derive_id(small_url_encode(format!("deref-methods-{:#}", type_.print(cx))));
1034 if let Some(def_id) = type_.def_id(cx.cache()) {
1035 cx.deref_id_map.borrow_mut().insert(def_id, id.clone());
1039 "<h2 id=\"{id}\" class=\"small-section-header\">\
1040 <span>Methods from {trait_}<Target = {type_}></span>\
1041 <a href=\"#{id}\" class=\"anchor\"></a>\
1044 trait_ = trait_.print(cx),
1045 type_ = type_.print(cx),
1047 (RenderMode::ForDeref { mut_: deref_mut_ }, cx.derive_id(id))
1050 let mut impls_buf = Buffer::empty_from(w);
1051 for i in &non_trait {
1057 AssocItemLink::Anchor(None),
1061 ImplRenderingParameters {
1062 show_def_docs: true,
1063 is_on_foreign_type: false,
1064 show_default_items: true,
1065 show_non_assoc_items: true,
1066 toggle_open_by_default: true,
1070 if !impls_buf.is_empty() {
1071 w.push_buffer(tmp_buf);
1072 write!(w, "<div id=\"{}\">", id);
1073 w.push_buffer(impls_buf);
1074 w.write_str("</div>");
1078 if !traits.is_empty() {
1080 traits.iter().find(|t| t.trait_did() == cx.tcx().lang_items().deref_trait());
1081 if let Some(impl_) = deref_impl {
1083 traits.iter().any(|t| t.trait_did() == cx.tcx().lang_items().deref_mut_trait());
1084 render_deref_methods(w, cx, impl_, containing_item, has_deref_mut, derefs);
1087 // If we were already one level into rendering deref methods, we don't want to render
1088 // anything after recursing into any further deref methods above.
1089 if let AssocItemRender::DerefFor { .. } = what {
1093 let (synthetic, concrete): (Vec<&&Impl>, Vec<&&Impl>) =
1094 traits.iter().partition(|t| t.inner_impl().kind.is_auto());
1095 let (blanket_impl, concrete): (Vec<&&Impl>, _) =
1096 concrete.into_iter().partition(|t| t.inner_impl().kind.is_blanket());
1098 let mut impls = Buffer::empty_from(w);
1099 render_impls(cx, &mut impls, &concrete, containing_item, true);
1100 let impls = impls.into_inner();
1101 if !impls.is_empty() {
1104 "<h2 id=\"trait-implementations\" class=\"small-section-header\">\
1105 Trait Implementations\
1106 <a href=\"#trait-implementations\" class=\"anchor\"></a>\
1108 <div id=\"trait-implementations-list\">{}</div>",
1113 if !synthetic.is_empty() {
1115 "<h2 id=\"synthetic-implementations\" class=\"small-section-header\">\
1116 Auto Trait Implementations\
1117 <a href=\"#synthetic-implementations\" class=\"anchor\"></a>\
1119 <div id=\"synthetic-implementations-list\">",
1121 render_impls(cx, w, &synthetic, containing_item, false);
1122 w.write_str("</div>");
1125 if !blanket_impl.is_empty() {
1127 "<h2 id=\"blanket-implementations\" class=\"small-section-header\">\
1128 Blanket Implementations\
1129 <a href=\"#blanket-implementations\" class=\"anchor\"></a>\
1131 <div id=\"blanket-implementations-list\">",
1133 render_impls(cx, w, &blanket_impl, containing_item, false);
1134 w.write_str("</div>");
1139 fn render_deref_methods(
1143 container_item: &clean::Item,
1145 derefs: &mut FxHashSet<DefId>,
1147 let cache = cx.cache();
1148 let deref_type = impl_.inner_impl().trait_.as_ref().unwrap();
1149 let (target, real_target) = impl_
1153 .find_map(|item| match *item.kind {
1154 clean::AssocTypeItem(ref t, _) => Some(match *t {
1155 clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
1156 _ => (&t.type_, &t.type_),
1160 .expect("Expected associated type binding");
1161 debug!("Render deref methods for {:#?}, target {:#?}", impl_.inner_impl().for_, target);
1163 AssocItemRender::DerefFor { trait_: deref_type, type_: real_target, deref_mut_: deref_mut };
1164 if let Some(did) = target.def_id(cache) {
1165 if let Some(type_did) = impl_.inner_impl().for_.def_id(cache) {
1166 // `impl Deref<Target = S> for S`
1167 if did == type_did || !derefs.insert(did) {
1168 // Avoid infinite cycles
1172 render_assoc_items_inner(w, cx, container_item, did, what, derefs);
1173 } else if let Some(prim) = target.primitive_type() {
1174 if let Some(&did) = cache.primitive_locations.get(&prim) {
1175 render_assoc_items_inner(w, cx, container_item, did, what, derefs);
1180 fn should_render_item(item: &clean::Item, deref_mut_: bool, tcx: TyCtxt<'_>) -> bool {
1181 let self_type_opt = match *item.kind {
1182 clean::MethodItem(ref method, _) => method.decl.self_type(),
1183 clean::TyMethodItem(ref method) => method.decl.self_type(),
1187 if let Some(self_ty) = self_type_opt {
1188 let (by_mut_ref, by_box, by_value) = match self_ty {
1189 SelfTy::SelfBorrowed(_, mutability)
1190 | SelfTy::SelfExplicit(clean::BorrowedRef { mutability, .. }) => {
1191 (mutability == Mutability::Mut, false, false)
1193 SelfTy::SelfExplicit(clean::Type::Path { path }) => {
1194 (false, Some(path.def_id()) == tcx.lang_items().owned_box(), false)
1196 SelfTy::SelfValue => (false, false, true),
1197 _ => (false, false, false),
1200 (deref_mut_ || !by_mut_ref) && !by_box && !by_value
1206 fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
1207 let mut out = Buffer::html();
1209 if let Some((did, ty)) = decl.output.as_return().and_then(|t| Some((t.def_id(cx.cache())?, t)))
1211 if let Some(impls) = cx.cache().impls.get(&did) {
1213 let impl_ = i.inner_impl();
1214 if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache())
1216 // Two different types might have the same did,
1217 // without actually being the same.
1220 if let Some(trait_) = &impl_.trait_ {
1221 let trait_did = trait_.def_id();
1223 if cx.cache().traits.get(&trait_did).map_or(false, |t| t.is_notable) {
1227 "<span class=\"notable\">Notable traits for {}</span>\
1228 <code class=\"content\">",
1229 impl_.for_.print(cx)
1233 //use the "where" class here to make it small
1236 "<span class=\"where fmt-newline\">{}</span>",
1237 impl_.print(false, cx)
1239 for it in &impl_.items {
1240 if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
1241 out.push_str("<span class=\"where fmt-newline\"> ");
1242 let empty_set = FxHashSet::default();
1244 AssocItemLink::GotoSource(trait_did.into(), &empty_set);
1249 &[], // intentionally leaving out bounds
1255 out.push_str(";</span>");
1264 if !out.is_empty() {
1267 "<span class=\"notable-traits\"><span class=\"notable-traits-tooltip\">ⓘ\
1268 <span class=\"notable-traits-tooltiptext\"><span class=\"docblock\">",
1270 out.push_str("</code></span></span></span></span>");
1276 #[derive(Clone, Copy, Debug)]
1277 struct ImplRenderingParameters {
1278 show_def_docs: bool,
1279 is_on_foreign_type: bool,
1280 show_default_items: bool,
1281 /// Whether or not to show methods.
1282 show_non_assoc_items: bool,
1283 toggle_open_by_default: bool,
1290 parent: &clean::Item,
1291 link: AssocItemLink<'_>,
1292 render_mode: RenderMode,
1293 use_absolute: Option<bool>,
1295 rendering_params: ImplRenderingParameters,
1297 let cache = cx.cache();
1298 let traits = &cache.traits;
1299 let trait_ = i.trait_did().map(|did| &traits[&did]);
1300 let mut close_tags = String::new();
1302 // For trait implementations, the `interesting` output contains all methods that have doc
1303 // comments, and the `boring` output contains all methods that do not. The distinction is
1304 // used to allow hiding the boring methods.
1305 // `containing_item` is used for rendering stability info. If the parent is a trait impl,
1306 // `containing_item` will the grandparent, since trait impls can't have stability attached.
1308 boring: &mut Buffer,
1309 interesting: &mut Buffer,
1312 parent: &clean::Item,
1313 containing_item: &clean::Item,
1314 link: AssocItemLink<'_>,
1315 render_mode: RenderMode,
1316 is_default_item: bool,
1317 trait_: Option<&clean::Trait>,
1318 rendering_params: ImplRenderingParameters,
1320 let item_type = item.type_();
1321 let name = item.name.as_ref().unwrap();
1323 let render_method_item = rendering_params.show_non_assoc_items
1324 && match render_mode {
1325 RenderMode::Normal => true,
1326 RenderMode::ForDeref { mut_: deref_mut_ } => {
1327 should_render_item(item, deref_mut_, cx.tcx())
1331 let in_trait_class = if trait_.is_some() { " trait-impl" } else { "" };
1333 let mut doc_buffer = Buffer::empty_from(boring);
1334 let mut info_buffer = Buffer::empty_from(boring);
1335 let mut short_documented = true;
1337 if render_method_item {
1338 if !is_default_item {
1339 if let Some(t) = trait_ {
1340 // The trait item may have been stripped so we might not
1341 // find any documentation or stability for it.
1342 if let Some(it) = t.items.iter().find(|i| i.name == item.name) {
1343 // We need the stability of the item from the trait
1344 // because impls can't have a stability.
1345 if item.doc_value().is_some() {
1346 document_item_info(&mut info_buffer, cx, it, Some(parent));
1347 document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
1348 short_documented = false;
1350 // In case the item isn't documented,
1351 // provide short documentation from the trait.
1358 rendering_params.show_def_docs,
1363 document_item_info(&mut info_buffer, cx, item, Some(parent));
1364 if rendering_params.show_def_docs {
1365 document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
1366 short_documented = false;
1376 rendering_params.show_def_docs,
1380 let w = if short_documented && trait_.is_some() { interesting } else { boring };
1382 let toggled = !doc_buffer.is_empty();
1384 let method_toggle_class =
1385 if item_type == ItemType::Method { " method-toggle" } else { "" };
1386 write!(w, "<details class=\"rustdoc-toggle{}\" open><summary>", method_toggle_class);
1389 clean::MethodItem(..) | clean::TyMethodItem(_) => {
1390 // Only render when the method is not static or we allow static methods
1391 if render_method_item {
1392 let id = cx.derive_id(format!("{}.{}", item_type, name));
1393 let source_id = trait_
1394 .and_then(|trait_| {
1395 trait_.items.iter().find(|item| {
1396 item.name.map(|n| n.as_str().eq(name.as_str())).unwrap_or(false)
1399 .map(|item| format!("{}.{}", item.type_(), name));
1402 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1403 id, item_type, in_trait_class,
1405 render_rightside(w, cx, item, containing_item, render_mode);
1406 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1407 w.write_str("<h4 class=\"code-header\">");
1411 link.anchor(source_id.as_ref().unwrap_or(&id)),
1416 w.write_str("</h4>");
1417 w.write_str("</section>");
1420 kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => {
1421 let source_id = format!("{}.{}", item_type, name);
1422 let id = cx.derive_id(source_id.clone());
1425 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1426 id, item_type, in_trait_class
1428 render_rightside(w, cx, item, containing_item, render_mode);
1429 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1430 w.write_str("<h4 class=\"code-header\">");
1436 clean::TyAssocConstItem(_) => None,
1437 clean::AssocConstItem(_, default) => Some(default),
1438 _ => unreachable!(),
1440 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1444 w.write_str("</h4>");
1445 w.write_str("</section>");
1447 clean::TyAssocTypeItem(generics, bounds) => {
1448 let source_id = format!("{}.{}", item_type, name);
1449 let id = cx.derive_id(source_id.clone());
1450 write!(w, "<section id=\"{}\" class=\"{}{}\">", id, item_type, in_trait_class);
1451 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1452 w.write_str("<h4 class=\"code-header\">");
1459 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1463 w.write_str("</h4>");
1464 w.write_str("</section>");
1466 clean::AssocTypeItem(tydef, _bounds) => {
1467 let source_id = format!("{}.{}", item_type, name);
1468 let id = cx.derive_id(source_id.clone());
1471 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1472 id, item_type, in_trait_class
1474 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1475 w.write_str("<h4 class=\"code-header\">");
1480 &[], // intentionally leaving out bounds
1481 Some(tydef.item_type.as_ref().unwrap_or(&tydef.type_)),
1482 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1486 w.write_str("</h4>");
1487 w.write_str("</section>");
1489 clean::StrippedItem(..) => return,
1490 _ => panic!("can't make docs for trait item with name {:?}", item.name),
1493 w.push_buffer(info_buffer);
1495 w.write_str("</summary>");
1496 w.push_buffer(doc_buffer);
1497 w.push_str("</details>");
1501 let mut impl_items = Buffer::empty_from(w);
1502 let mut default_impl_items = Buffer::empty_from(w);
1504 for trait_item in &i.inner_impl().items {
1506 &mut default_impl_items,
1510 if trait_.is_some() { &i.impl_item } else { parent },
1515 trait_.map(|t| &t.trait_),
1520 fn render_default_items(
1521 boring: &mut Buffer,
1522 interesting: &mut Buffer,
1526 parent: &clean::Item,
1527 containing_item: &clean::Item,
1528 render_mode: RenderMode,
1529 rendering_params: ImplRenderingParameters,
1531 for trait_item in &t.items {
1532 let n = trait_item.name;
1533 if i.items.iter().any(|m| m.name == n) {
1536 let did = i.trait_.as_ref().unwrap().def_id();
1537 let provided_methods = i.provided_trait_methods(cx.tcx());
1538 let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_methods);
1556 // If we've implemented a trait, then also emit documentation for all
1557 // default items which weren't overridden in the implementation block.
1558 // We don't emit documentation for default items if they appear in the
1559 // Implementations on Foreign Types or Implementors sections.
1560 if rendering_params.show_default_items {
1561 if let Some(t) = trait_ {
1562 render_default_items(
1563 &mut default_impl_items,
1575 if render_mode == RenderMode::Normal {
1576 let toggled = !(impl_items.is_empty() && default_impl_items.is_empty());
1578 close_tags.insert_str(0, "</details>");
1581 "<details class=\"rustdoc-toggle implementors-toggle\"{}>",
1582 if rendering_params.toggle_open_by_default { " open" } else { "" }
1584 write!(w, "<summary>")
1586 render_impl_summary(
1592 rendering_params.show_def_docs,
1594 rendering_params.is_on_foreign_type,
1598 write!(w, "</summary>")
1601 if let Some(ref dox) = i.impl_item.collapsed_doc_value() {
1602 let mut ids = cx.id_map.borrow_mut();
1605 "<div class=\"docblock\">{}</div>",
1608 links: &i.impl_item.links(cx),
1610 error_codes: cx.shared.codes,
1611 edition: cx.shared.edition(),
1612 playground: &cx.shared.playground,
1613 heading_offset: HeadingOffset::H4
1619 if !default_impl_items.is_empty() || !impl_items.is_empty() {
1620 w.write_str("<div class=\"impl-items\">");
1621 w.push_buffer(default_impl_items);
1622 w.push_buffer(impl_items);
1623 close_tags.insert_str(0, "</div>");
1625 w.write_str(&close_tags);
1628 // Render the items that appear on the right side of methods, impls, and
1629 // associated types. For example "1.0.0 (const: 1.39.0) · source".
1630 fn render_rightside(
1634 containing_item: &clean::Item,
1635 render_mode: RenderMode,
1639 // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
1641 let (const_stability, const_stable_since) = match render_mode {
1642 RenderMode::Normal => (item.const_stability(tcx), containing_item.const_stable_since(tcx)),
1643 RenderMode::ForDeref { .. } => (None, None),
1646 let mut rightside = Buffer::new();
1647 let has_stability = render_stability_since_raw(
1649 item.stable_since(tcx),
1651 containing_item.stable_since(tcx),
1654 let mut srclink = Buffer::empty_from(w);
1655 write_srclink(cx, item, &mut srclink);
1656 if has_stability && !srclink.is_empty() {
1657 rightside.write_str(" · ");
1659 rightside.push_buffer(srclink);
1660 if !rightside.is_empty() {
1661 write!(w, "<span class=\"rightside\">{}</span>", rightside.into_inner());
1665 pub(crate) fn render_impl_summary(
1669 parent: &clean::Item,
1670 containing_item: &clean::Item,
1671 show_def_docs: bool,
1672 use_absolute: Option<bool>,
1673 is_on_foreign_type: bool,
1674 // This argument is used to reference same type with different paths to avoid duplication
1675 // in documentation pages for trait with automatic implementations like "Send" and "Sync".
1678 let id = cx.derive_id(match i.inner_impl().trait_ {
1680 if is_on_foreign_type {
1681 get_id_for_impl_on_foreign_type(&i.inner_impl().for_, t, cx)
1683 format!("impl-{}", small_url_encode(format!("{:#}", t.print(cx))))
1686 None => "impl".to_string(),
1688 let aliases = if aliases.is_empty() {
1691 format!(" data-aliases=\"{}\"", aliases.join(","))
1693 write!(w, "<section id=\"{}\" class=\"impl has-srclink\"{}>", id, aliases);
1694 render_rightside(w, cx, &i.impl_item, containing_item, RenderMode::Normal);
1695 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1696 write!(w, "<h3 class=\"code-header in-band\">");
1698 if let Some(use_absolute) = use_absolute {
1699 write!(w, "{}", i.inner_impl().print(use_absolute, cx));
1701 for it in &i.inner_impl().items {
1702 if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
1703 w.write_str("<span class=\"where fmt-newline\"> ");
1708 &[], // intentionally leaving out bounds
1710 AssocItemLink::Anchor(None),
1714 w.write_str(";</span>");
1719 write!(w, "{}", i.inner_impl().print(false, cx));
1723 let is_trait = i.inner_impl().trait_.is_some();
1725 if let Some(portability) = portability(&i.impl_item, Some(parent)) {
1726 write!(w, "<span class=\"item-info\">{}</span>", portability);
1730 w.write_str("</section>");
1733 fn print_sidebar(cx: &Context<'_>, it: &clean::Item, buffer: &mut Buffer) {
1734 let parentlen = cx.current.len() - if it.is_mod() { 1 } else { 0 };
1738 || it.is_primitive()
1746 "<h2 class=\"location\"><a href=\"#\">{}{}</a></h2>",
1748 clean::ModuleItem(..) =>
1756 it.name.as_ref().unwrap()
1760 buffer.write_str("<div class=\"sidebar-elems\">");
1762 write!(buffer, "<div class=\"block\"><ul>");
1763 if let Some(ref version) = cx.cache().crate_version {
1764 write!(buffer, "<li class=\"version\">Version {}</li>", Escape(version));
1766 write!(buffer, "<li><a id=\"all-types\" href=\"all.html\">All Items</a></li>");
1767 buffer.write_str("</div></ul>");
1771 clean::StructItem(ref s) => sidebar_struct(cx, buffer, it, s),
1772 clean::TraitItem(ref t) => sidebar_trait(cx, buffer, it, t),
1773 clean::PrimitiveItem(_) => sidebar_primitive(cx, buffer, it),
1774 clean::UnionItem(ref u) => sidebar_union(cx, buffer, it, u),
1775 clean::EnumItem(ref e) => sidebar_enum(cx, buffer, it, e),
1776 clean::TypedefItem(_) => sidebar_typedef(cx, buffer, it),
1777 clean::ModuleItem(ref m) => sidebar_module(buffer, &m.items),
1778 clean::ForeignTypeItem => sidebar_foreign_type(cx, buffer, it),
1782 // The sidebar is designed to display sibling functions, modules and
1783 // other miscellaneous information. since there are lots of sibling
1784 // items (and that causes quadratic growth in large modules),
1785 // we refactor common parts into a shared JavaScript file per module.
1786 // still, we don't move everything into JS because we want to preserve
1787 // as much HTML as possible in order to allow non-JS-enabled browsers
1788 // to navigate the documentation (though slightly inefficiently).
1791 let path: String = cx.current.iter().map(|s| s.as_str()).intersperse("::").collect();
1793 write!(buffer, "<h2 class=\"location\"><a href=\"index.html\">In {}</a></h2>", path);
1796 // Sidebar refers to the enclosing module, not this module.
1797 let relpath = if it.is_mod() && parentlen != 0 { "./" } else { "" };
1800 "<div id=\"sidebar-vars\" data-name=\"{name}\" data-ty=\"{ty}\" data-relpath=\"{path}\">\
1802 name = it.name.unwrap_or(kw::Empty),
1808 "<script defer src=\"{}sidebar-items{}.js\"></script>",
1809 relpath, cx.shared.resource_suffix
1811 // Closes sidebar-elems div.
1812 buffer.write_str("</div>");
1815 fn get_next_url(used_links: &mut FxHashSet<String>, url: String) -> String {
1816 if used_links.insert(url.clone()) {
1820 while !used_links.insert(format!("{}-{}", url, add)) {
1823 format!("{}-{}", url, add)
1826 struct SidebarLink {
1831 impl fmt::Display for SidebarLink {
1832 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1833 write!(f, "<a href=\"#{}\">{}</a>", self.url, self.name)
1837 impl PartialEq for SidebarLink {
1838 fn eq(&self, other: &Self) -> bool {
1839 self.url == other.url
1843 impl Eq for SidebarLink {}
1845 impl PartialOrd for SidebarLink {
1846 fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
1847 Some(self.cmp(other))
1851 impl Ord for SidebarLink {
1852 fn cmp(&self, other: &Self) -> std::cmp::Ordering {
1853 self.url.cmp(&other.url)
1860 used_links: &mut FxHashSet<String>,
1863 ) -> Vec<SidebarLink> {
1866 .filter_map(|item| match item.name {
1867 Some(name) if !name.is_empty() && item.is_method() => {
1868 if !for_deref || should_render_item(item, deref_mut, tcx) {
1871 url: get_next_url(used_links, format!("{}.{}", ItemType::Method, name)),
1879 .collect::<Vec<_>>()
1882 fn get_associated_constants(
1884 used_links: &mut FxHashSet<String>,
1885 ) -> Vec<SidebarLink> {
1888 .filter_map(|item| match item.name {
1889 Some(name) if !name.is_empty() && item.is_associated_const() => Some(SidebarLink {
1891 url: get_next_url(used_links, format!("{}.{}", ItemType::AssocConst, name)),
1895 .collect::<Vec<_>>()
1898 // The point is to url encode any potential character from a type with genericity.
1899 fn small_url_encode(s: String) -> String {
1900 let mut st = String::new();
1901 let mut last_match = 0;
1902 for (idx, c) in s.char_indices() {
1903 let escaped = match c {
1919 st += &s[last_match..idx];
1921 // NOTE: we only expect single byte characters here - which is fine as long as we
1922 // only match single byte characters
1923 last_match = idx + 1;
1926 if last_match != 0 {
1927 st += &s[last_match..];
1934 fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
1935 let did = it.item_id.expect_def_id();
1936 let cache = cx.cache();
1938 if let Some(v) = cache.impls.get(&did) {
1939 let mut used_links = FxHashSet::default();
1940 let mut id_map = IdMap::new();
1943 let used_links_bor = &mut used_links;
1944 let mut assoc_consts = v
1946 .filter(|i| i.inner_impl().trait_.is_none())
1947 .flat_map(|i| get_associated_constants(i.inner_impl(), used_links_bor))
1948 .collect::<Vec<_>>();
1949 if !assoc_consts.is_empty() {
1950 // We want links' order to be reproducible so we don't use unstable sort.
1951 assoc_consts.sort();
1953 print_sidebar_block(
1956 "Associated Constants",
1957 assoc_consts.iter(),
1962 .filter(|i| i.inner_impl().trait_.is_none())
1963 .flat_map(|i| get_methods(i.inner_impl(), false, used_links_bor, false, cx.tcx()))
1964 .collect::<Vec<_>>();
1965 if !methods.is_empty() {
1966 // We want links' order to be reproducible so we don't use unstable sort.
1969 print_sidebar_block(out, "implementations", "Methods", methods.iter());
1973 if v.iter().any(|i| i.inner_impl().trait_.is_some()) {
1974 if let Some(impl_) =
1975 v.iter().find(|i| i.trait_did() == cx.tcx().lang_items().deref_trait())
1977 let mut derefs = FxHashSet::default();
1979 sidebar_deref_methods(cx, out, impl_, v, &mut derefs);
1982 let format_impls = |impls: Vec<&Impl>, id_map: &mut IdMap| {
1983 let mut links = FxHashSet::default();
1988 if let Some(ref i) = it.inner_impl().trait_ {
1989 let i_display = format!("{:#}", i.print(cx));
1990 let out = Escape(&i_display);
1992 id_map.derive(small_url_encode(format!("impl-{:#}", i.print(cx))));
1993 let prefix = match it.inner_impl().polarity {
1994 ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => "",
1995 ty::ImplPolarity::Negative => "!",
1998 format!("<a href=\"#{}\">{}{}</a>", encoded, prefix, out);
1999 if links.insert(generated.clone()) { Some(generated) } else { None }
2004 .collect::<Vec<String>>();
2009 let (synthetic, concrete): (Vec<&Impl>, Vec<&Impl>) =
2010 v.iter().partition::<Vec<_>, _>(|i| i.inner_impl().kind.is_auto());
2011 let (blanket_impl, concrete): (Vec<&Impl>, Vec<&Impl>) =
2012 concrete.into_iter().partition::<Vec<_>, _>(|i| i.inner_impl().kind.is_blanket());
2014 let concrete_format = format_impls(concrete, &mut id_map);
2015 let synthetic_format = format_impls(synthetic, &mut id_map);
2016 let blanket_format = format_impls(blanket_impl, &mut id_map);
2018 if !concrete_format.is_empty() {
2019 print_sidebar_block(
2021 "trait-implementations",
2022 "Trait Implementations",
2023 concrete_format.iter(),
2027 if !synthetic_format.is_empty() {
2028 print_sidebar_block(
2030 "synthetic-implementations",
2031 "Auto Trait Implementations",
2032 synthetic_format.iter(),
2036 if !blanket_format.is_empty() {
2037 print_sidebar_block(
2039 "blanket-implementations",
2040 "Blanket Implementations",
2041 blanket_format.iter(),
2048 fn sidebar_deref_methods(
2053 derefs: &mut FxHashSet<DefId>,
2057 debug!("found Deref: {:?}", impl_);
2058 if let Some((target, real_target)) =
2059 impl_.inner_impl().items.iter().find_map(|item| match *item.kind {
2060 clean::AssocTypeItem(ref t, _) => Some(match *t {
2061 clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
2062 _ => (&t.type_, &t.type_),
2067 debug!("found target, real_target: {:?} {:?}", target, real_target);
2068 if let Some(did) = target.def_id(c) {
2069 if let Some(type_did) = impl_.inner_impl().for_.def_id(c) {
2070 // `impl Deref<Target = S> for S`
2071 if did == type_did || !derefs.insert(did) {
2072 // Avoid infinite cycles
2077 let deref_mut = v.iter().any(|i| i.trait_did() == cx.tcx().lang_items().deref_mut_trait());
2078 let inner_impl = target
2081 target.primitive_type().and_then(|prim| c.primitive_locations.get(&prim).cloned())
2083 .and_then(|did| c.impls.get(&did));
2084 if let Some(impls) = inner_impl {
2085 debug!("found inner_impl: {:?}", impls);
2086 let mut used_links = FxHashSet::default();
2089 .filter(|i| i.inner_impl().trait_.is_none())
2091 get_methods(i.inner_impl(), true, &mut used_links, deref_mut, cx.tcx())
2093 .collect::<Vec<_>>();
2094 if !ret.is_empty() {
2096 let id = if let Some(target_def_id) = real_target.def_id(c) {
2097 map = cx.deref_id_map.borrow();
2098 map.get(&target_def_id).expect("Deref section without derived id")
2102 let title = format!(
2103 "Methods from {}<Target={}>",
2104 Escape(&format!("{:#}", impl_.inner_impl().trait_.as_ref().unwrap().print(cx))),
2105 Escape(&format!("{:#}", real_target.print(cx))),
2107 // We want links' order to be reproducible so we don't use unstable sort.
2109 print_sidebar_block(out, id, &title, ret.iter());
2113 // Recurse into any further impls that might exist for `target`
2114 if let Some(target_did) = target.def_id(c) {
2115 if let Some(target_impls) = c.impls.get(&target_did) {
2116 if let Some(target_deref_impl) = target_impls.iter().find(|i| {
2120 .map(|t| Some(t.def_id()) == cx.tcx().lang_items().deref_trait())
2123 sidebar_deref_methods(cx, out, target_deref_impl, target_impls, derefs);
2130 fn sidebar_struct(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, s: &clean::Struct) {
2131 let mut sidebar = Buffer::new();
2132 let fields = get_struct_fields_name(&s.fields);
2134 if !fields.is_empty() {
2135 match s.struct_type {
2136 CtorKind::Fictive => {
2137 print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
2139 CtorKind::Fn => print_sidebar_title(&mut sidebar, "fields", "Tuple Fields"),
2140 CtorKind::Const => {}
2144 sidebar_assoc_items(cx, &mut sidebar, it);
2146 if !sidebar.is_empty() {
2147 write!(buf, "<section>{}</section>", sidebar.into_inner());
2151 fn get_id_for_impl_on_foreign_type(
2153 trait_: &clean::Path,
2156 small_url_encode(format!("impl-{:#}-for-{:#}", trait_.print(cx), for_.print(cx)))
2159 fn extract_for_impl_name(item: &clean::Item, cx: &Context<'_>) -> Option<(String, String)> {
2161 clean::ItemKind::ImplItem(ref i) => {
2162 i.trait_.as_ref().map(|trait_| {
2163 // Alternative format produces no URLs,
2164 // so this parameter does nothing.
2166 format!("{:#}", i.for_.print(cx)),
2167 get_id_for_impl_on_foreign_type(&i.for_, trait_, cx),
2175 /// Don't call this function directly!!! Use `print_sidebar_title` or `print_sidebar_block` instead!
2176 fn print_sidebar_title_inner(buf: &mut Buffer, id: &str, title: &str) {
2179 "<h3 class=\"sidebar-title\">\
2180 <a href=\"#{}\">{}</a>\
2186 fn print_sidebar_title(buf: &mut Buffer, id: &str, title: &str) {
2187 buf.push_str("<div class=\"block\">");
2188 print_sidebar_title_inner(buf, id, title);
2189 buf.push_str("</div>");
2192 fn print_sidebar_block(
2196 items: impl Iterator<Item = impl fmt::Display>,
2198 buf.push_str("<div class=\"block\">");
2199 print_sidebar_title_inner(buf, id, title);
2200 buf.push_str("<ul>");
2202 write!(buf, "<li>{}</li>", item);
2204 buf.push_str("</ul></div>");
2207 fn sidebar_trait(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, t: &clean::Trait) {
2208 buf.write_str("<section>");
2210 fn print_sidebar_section(
2212 items: &[clean::Item],
2215 filter: impl Fn(&clean::Item) -> bool,
2216 mapper: impl Fn(&str) -> String,
2218 let mut items: Vec<&str> = items
2220 .filter_map(|m| match m.name {
2221 Some(ref name) if filter(m) => Some(name.as_str()),
2224 .collect::<Vec<_>>();
2226 if !items.is_empty() {
2227 items.sort_unstable();
2228 print_sidebar_block(out, id, title, items.into_iter().map(mapper));
2232 print_sidebar_section(
2235 "required-associated-types",
2236 "Required Associated Types",
2237 |m| m.is_ty_associated_type(),
2238 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocType),
2241 print_sidebar_section(
2244 "provided-associated-types",
2245 "Provided Associated Types",
2246 |m| m.is_associated_type(),
2247 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocType),
2250 print_sidebar_section(
2253 "required-associated-consts",
2254 "Required Associated Constants",
2255 |m| m.is_ty_associated_const(),
2256 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocConst),
2259 print_sidebar_section(
2262 "provided-associated-consts",
2263 "Provided Associated Constants",
2264 |m| m.is_associated_const(),
2265 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocConst),
2268 print_sidebar_section(
2273 |m| m.is_ty_method(),
2274 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::TyMethod),
2277 print_sidebar_section(
2283 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::Method),
2286 let cache = cx.cache();
2287 if let Some(implementors) = cache.implementors.get(&it.item_id.expect_def_id()) {
2288 let mut res = implementors
2291 i.inner_impl().for_.def_id(cache).map_or(false, |d| !cache.paths.contains_key(&d))
2293 .filter_map(|i| extract_for_impl_name(&i.impl_item, cx))
2294 .collect::<Vec<_>>();
2296 if !res.is_empty() {
2298 print_sidebar_block(
2301 "Implementations on Foreign Types",
2302 res.iter().map(|(name, id)| format!("<a href=\"#{}\">{}</a>", id, Escape(&name))),
2307 sidebar_assoc_items(cx, buf, it);
2309 print_sidebar_title(buf, "implementors", "Implementors");
2311 print_sidebar_title(buf, "synthetic-implementors", "Auto Implementors");
2314 buf.push_str("</section>")
2317 fn sidebar_primitive(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2318 let mut sidebar = Buffer::new();
2319 sidebar_assoc_items(cx, &mut sidebar, it);
2321 if !sidebar.is_empty() {
2322 write!(buf, "<section>{}</section>", sidebar.into_inner());
2326 fn sidebar_typedef(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2327 let mut sidebar = Buffer::new();
2328 sidebar_assoc_items(cx, &mut sidebar, it);
2330 if !sidebar.is_empty() {
2331 write!(buf, "<section>{}</section>", sidebar.into_inner());
2335 fn get_struct_fields_name(fields: &[clean::Item]) -> Vec<String> {
2336 let mut fields = fields
2338 .filter(|f| matches!(*f.kind, clean::StructFieldItem(..)))
2340 f.name.map(|name| format!("<a href=\"#structfield.{name}\">{name}</a>", name = name))
2342 .collect::<Vec<_>>();
2347 fn sidebar_union(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, u: &clean::Union) {
2348 let mut sidebar = Buffer::new();
2349 let fields = get_struct_fields_name(&u.fields);
2351 if !fields.is_empty() {
2352 print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
2355 sidebar_assoc_items(cx, &mut sidebar, it);
2357 if !sidebar.is_empty() {
2358 write!(buf, "<section>{}</section>", sidebar.into_inner());
2362 fn sidebar_enum(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, e: &clean::Enum) {
2363 let mut sidebar = Buffer::new();
2365 let mut variants = e
2371 .map(|name| format!("<a href=\"#variant.{name}\">{name}</a>", name = name))
2373 .collect::<Vec<_>>();
2374 if !variants.is_empty() {
2375 variants.sort_unstable();
2376 print_sidebar_block(&mut sidebar, "variants", "Variants", variants.iter());
2379 sidebar_assoc_items(cx, &mut sidebar, it);
2381 if !sidebar.is_empty() {
2382 write!(buf, "<section>{}</section>", sidebar.into_inner());
2386 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
2406 AssociatedConstants,
2416 const ALL: &'static [Self] = {
2418 // NOTE: The order here affects the order in the UI.
2438 AssociatedConstants,
2448 fn id(self) -> &'static str {
2450 Self::Reexports => "reexports",
2451 Self::Modules => "modules",
2452 Self::Structs => "structs",
2453 Self::Unions => "unions",
2454 Self::Enums => "enums",
2455 Self::Functions => "functions",
2456 Self::TypeDefinitions => "types",
2457 Self::Statics => "statics",
2458 Self::Constants => "constants",
2459 Self::Traits => "traits",
2460 Self::Implementations => "impls",
2461 Self::TypeMethods => "tymethods",
2462 Self::Methods => "methods",
2463 Self::StructFields => "fields",
2464 Self::Variants => "variants",
2465 Self::Macros => "macros",
2466 Self::PrimitiveTypes => "primitives",
2467 Self::AssociatedTypes => "associated-types",
2468 Self::AssociatedConstants => "associated-consts",
2469 Self::ForeignTypes => "foreign-types",
2470 Self::Keywords => "keywords",
2471 Self::OpaqueTypes => "opaque-types",
2472 Self::AttributeMacros => "attributes",
2473 Self::DeriveMacros => "derives",
2474 Self::TraitAliases => "trait-aliases",
2478 fn name(self) -> &'static str {
2480 Self::Reexports => "Re-exports",
2481 Self::Modules => "Modules",
2482 Self::Structs => "Structs",
2483 Self::Unions => "Unions",
2484 Self::Enums => "Enums",
2485 Self::Functions => "Functions",
2486 Self::TypeDefinitions => "Type Definitions",
2487 Self::Statics => "Statics",
2488 Self::Constants => "Constants",
2489 Self::Traits => "Traits",
2490 Self::Implementations => "Implementations",
2491 Self::TypeMethods => "Type Methods",
2492 Self::Methods => "Methods",
2493 Self::StructFields => "Struct Fields",
2494 Self::Variants => "Variants",
2495 Self::Macros => "Macros",
2496 Self::PrimitiveTypes => "Primitive Types",
2497 Self::AssociatedTypes => "Associated Types",
2498 Self::AssociatedConstants => "Associated Constants",
2499 Self::ForeignTypes => "Foreign Types",
2500 Self::Keywords => "Keywords",
2501 Self::OpaqueTypes => "Opaque Types",
2502 Self::AttributeMacros => "Attribute Macros",
2503 Self::DeriveMacros => "Derive Macros",
2504 Self::TraitAliases => "Trait Aliases",
2509 fn item_ty_to_section(ty: ItemType) -> ItemSection {
2511 ItemType::ExternCrate | ItemType::Import => ItemSection::Reexports,
2512 ItemType::Module => ItemSection::Modules,
2513 ItemType::Struct => ItemSection::Structs,
2514 ItemType::Union => ItemSection::Unions,
2515 ItemType::Enum => ItemSection::Enums,
2516 ItemType::Function => ItemSection::Functions,
2517 ItemType::Typedef => ItemSection::TypeDefinitions,
2518 ItemType::Static => ItemSection::Statics,
2519 ItemType::Constant => ItemSection::Constants,
2520 ItemType::Trait => ItemSection::Traits,
2521 ItemType::Impl => ItemSection::Implementations,
2522 ItemType::TyMethod => ItemSection::TypeMethods,
2523 ItemType::Method => ItemSection::Methods,
2524 ItemType::StructField => ItemSection::StructFields,
2525 ItemType::Variant => ItemSection::Variants,
2526 ItemType::Macro => ItemSection::Macros,
2527 ItemType::Primitive => ItemSection::PrimitiveTypes,
2528 ItemType::AssocType => ItemSection::AssociatedTypes,
2529 ItemType::AssocConst => ItemSection::AssociatedConstants,
2530 ItemType::ForeignType => ItemSection::ForeignTypes,
2531 ItemType::Keyword => ItemSection::Keywords,
2532 ItemType::OpaqueTy => ItemSection::OpaqueTypes,
2533 ItemType::ProcAttribute => ItemSection::AttributeMacros,
2534 ItemType::ProcDerive => ItemSection::DeriveMacros,
2535 ItemType::TraitAlias => ItemSection::TraitAliases,
2536 ItemType::Generic => unreachable!(),
2540 fn sidebar_module(buf: &mut Buffer, items: &[clean::Item]) {
2541 let mut sidebar = String::new();
2543 let item_sections_in_use: FxHashSet<_> = items
2550 if let clean::ImportItem(ref i) = *it.kind &&
2551 let clean::ImportKind::Simple(s) = i.kind { Some(s) } else { None }
2555 .map(|it| item_ty_to_section(it.type_()))
2557 for &sec in ItemSection::ALL.iter().filter(|sec| item_sections_in_use.contains(sec)) {
2558 sidebar.push_str(&format!("<li><a href=\"#{}\">{}</a></li>", sec.id(), sec.name()));
2561 if !sidebar.is_empty() {
2565 <div class=\"block\">\
2574 fn sidebar_foreign_type(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2575 let mut sidebar = Buffer::new();
2576 sidebar_assoc_items(cx, &mut sidebar, it);
2578 if !sidebar.is_empty() {
2579 write!(buf, "<section>{}</section>", sidebar.into_inner());
2583 pub(crate) const BASIC_KEYWORDS: &str = "rust, rustlang, rust-lang";
2585 /// Returns a list of all paths used in the type.
2586 /// This is used to help deduplicate imported impls
2587 /// for reexported types. If any of the contained
2588 /// types are re-exported, we don't use the corresponding
2589 /// entry from the js file, as inlining will have already
2590 /// picked up the impl
2591 fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
2592 let mut out = Vec::new();
2593 let mut visited = FxHashSet::default();
2594 let mut work = VecDeque::new();
2596 let mut process_path = |did: DefId| {
2597 let get_extern = || cache.external_paths.get(&did).map(|s| s.0.clone());
2598 let fqp = cache.exact_paths.get(&did).cloned().or_else(get_extern);
2600 if let Some(path) = fqp {
2601 out.push(join_with_double_colon(&path));
2605 work.push_back(first_ty);
2607 while let Some(ty) = work.pop_front() {
2608 if !visited.insert(ty.clone()) {
2613 clean::Type::Path { path } => process_path(path.def_id()),
2614 clean::Type::Tuple(tys) => {
2615 work.extend(tys.into_iter());
2617 clean::Type::Slice(ty) => {
2618 work.push_back(*ty);
2620 clean::Type::Array(ty, _) => {
2621 work.push_back(*ty);
2623 clean::Type::RawPointer(_, ty) => {
2624 work.push_back(*ty);
2626 clean::Type::BorrowedRef { type_, .. } => {
2627 work.push_back(*type_);
2629 clean::Type::QPath { self_type, trait_, .. } => {
2630 work.push_back(*self_type);
2631 process_path(trait_.def_id());
2639 const MAX_FULL_EXAMPLES: usize = 5;
2640 const NUM_VISIBLE_LINES: usize = 10;
2642 /// Generates the HTML for example call locations generated via the --scrape-examples flag.
2643 fn render_call_locations(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item) {
2645 let def_id = item.item_id.expect_def_id();
2646 let key = tcx.def_path_hash(def_id);
2647 let Some(call_locations) = cx.shared.call_locations.get(&key) else { return };
2649 // Generate a unique ID so users can link to this section for a given method
2650 let id = cx.id_map.borrow_mut().derive("scraped-examples");
2653 "<div class=\"docblock scraped-example-list\">\
2656 <a href=\"#{id}\">Examples found in repository</a>\
2657 <a class=\"scrape-help\" href=\"{root_path}scrape-examples-help.html\">?</a>\
2659 root_path = cx.root_path(),
2663 // Create a URL to a particular location in a reverse-dependency's source file
2664 let link_to_loc = |call_data: &CallData, loc: &CallLocation| -> (String, String) {
2665 let (line_lo, line_hi) = loc.call_expr.line_span;
2666 let (anchor, title) = if line_lo == line_hi {
2667 ((line_lo + 1).to_string(), format!("line {}", line_lo + 1))
2670 format!("{}-{}", line_lo + 1, line_hi + 1),
2671 format!("lines {}-{}", line_lo + 1, line_hi + 1),
2674 let url = format!("{}{}#{}", cx.root_path(), call_data.url, anchor);
2678 // Generate the HTML for a single example, being the title and code block
2679 let write_example = |w: &mut Buffer, (path, call_data): (&PathBuf, &CallData)| -> bool {
2680 let contents = match fs::read_to_string(&path) {
2681 Ok(contents) => contents,
2683 let span = item.span(tcx).inner();
2685 .span_err(span, &format!("failed to read file {}: {}", path.display(), err));
2690 // To reduce file sizes, we only want to embed the source code needed to understand the example, not
2691 // the entire file. So we find the smallest byte range that covers all items enclosing examples.
2692 assert!(!call_data.locations.is_empty());
2694 call_data.locations.iter().min_by_key(|loc| loc.enclosing_item.byte_span.0).unwrap();
2695 let byte_min = min_loc.enclosing_item.byte_span.0;
2696 let line_min = min_loc.enclosing_item.line_span.0;
2698 call_data.locations.iter().max_by_key(|loc| loc.enclosing_item.byte_span.1).unwrap();
2699 let byte_max = max_loc.enclosing_item.byte_span.1;
2700 let line_max = max_loc.enclosing_item.line_span.1;
2702 // The output code is limited to that byte range.
2703 let contents_subset = &contents[(byte_min as usize)..(byte_max as usize)];
2705 // The call locations need to be updated to reflect that the size of the program has changed.
2706 // Specifically, the ranges are all subtracted by `byte_min` since that's the new zero point.
2707 let (mut byte_ranges, line_ranges): (Vec<_>, Vec<_>) = call_data
2711 let (byte_lo, byte_hi) = loc.call_ident.byte_span;
2712 let (line_lo, line_hi) = loc.call_expr.line_span;
2713 let byte_range = (byte_lo - byte_min, byte_hi - byte_min);
2715 let line_range = (line_lo - line_min, line_hi - line_min);
2716 let (line_url, line_title) = link_to_loc(call_data, loc);
2718 (byte_range, (line_range, line_url, line_title))
2722 let (_, init_url, init_title) = &line_ranges[0];
2723 let needs_expansion = line_max - line_min > NUM_VISIBLE_LINES;
2724 let locations_encoded = serde_json::to_string(&line_ranges).unwrap();
2728 "<div class=\"scraped-example {expanded_cls}\" data-locs=\"{locations}\">\
2729 <div class=\"scraped-example-title\">\
2730 {name} (<a href=\"{url}\">{title}</a>)\
2732 <div class=\"code-wrapper\">",
2733 expanded_cls = if needs_expansion { "" } else { "expanded" },
2734 name = call_data.display_name,
2737 // The locations are encoded as a data attribute, so they can be read
2738 // later by the JS for interactions.
2739 locations = Escape(&locations_encoded)
2742 if line_ranges.len() > 1 {
2743 write!(w, r#"<span class="prev">≺</span> <span class="next">≻</span>"#);
2746 if needs_expansion {
2747 write!(w, r#"<span class="expand">↕</span>"#);
2750 // Look for the example file in the source map if it exists, otherwise return a dummy span
2751 let file_span = (|| {
2752 let source_map = tcx.sess.source_map();
2753 let crate_src = tcx.sess.local_crate_source_file.as_ref()?;
2754 let abs_crate_src = crate_src.canonicalize().ok()?;
2755 let crate_root = abs_crate_src.parent()?.parent()?;
2756 let rel_path = path.strip_prefix(crate_root).ok()?;
2757 let files = source_map.files();
2758 let file = files.iter().find(|file| match &file.name {
2759 FileName::Real(RealFileName::LocalPath(other_path)) => rel_path == other_path,
2762 Some(rustc_span::Span::with_root_ctxt(
2763 file.start_pos + BytePos(byte_min),
2764 file.start_pos + BytePos(byte_max),
2767 .unwrap_or(rustc_span::DUMMY_SP);
2769 // The root path is the inverse of Context::current
2770 let root_path = vec!["../"; cx.current.len() - 1].join("");
2772 let mut decoration_info = FxHashMap::default();
2773 decoration_info.insert("highlight focus", vec![byte_ranges.remove(0)]);
2774 decoration_info.insert("highlight", byte_ranges);
2783 Some(highlight::DecorationInfo(decoration_info)),
2784 sources::SourceContext::Embedded { offset: line_min },
2786 write!(w, "</div></div>");
2791 // The call locations are output in sequence, so that sequence needs to be determined.
2792 // Ideally the most "relevant" examples would be shown first, but there's no general algorithm
2793 // for determining relevance. Instead, we prefer the smallest examples being likely the easiest to
2794 // understand at a glance.
2795 let ordered_locations = {
2796 let sort_criterion = |(_, call_data): &(_, &CallData)| {
2797 // Use the first location because that's what the user will see initially
2798 let (lo, hi) = call_data.locations[0].enclosing_item.byte_span;
2802 let mut locs = call_locations.into_iter().collect::<Vec<_>>();
2803 locs.sort_by_key(sort_criterion);
2807 let mut it = ordered_locations.into_iter().peekable();
2809 // An example may fail to write if its source can't be read for some reason, so this method
2810 // continues iterating until a write succeeds
2811 let write_and_skip_failure = |w: &mut Buffer, it: &mut Peekable<_>| {
2812 while let Some(example) = it.next() {
2813 if write_example(&mut *w, example) {
2819 // Write just one example that's visible by default in the method's description.
2820 write_and_skip_failure(w, &mut it);
2822 // Then add the remaining examples in a hidden section.
2823 if it.peek().is_some() {
2826 "<details class=\"rustdoc-toggle more-examples-toggle\">\
2827 <summary class=\"hideme\">\
2828 <span>More examples</span>\
2830 <div class=\"hide-more\">Hide additional examples</div>\
2831 <div class=\"more-scraped-examples\">\
2832 <div class=\"toggle-line\"><div class=\"toggle-line-inner\"></div></div>\
2833 <div class=\"more-scraped-examples-inner\">"
2836 // Only generate inline code for MAX_FULL_EXAMPLES number of examples. Otherwise we could
2837 // make the page arbitrarily huge!
2838 for _ in 0..MAX_FULL_EXAMPLES {
2839 write_and_skip_failure(w, &mut it);
2842 // For the remaining examples, generate a <ul> containing links to the source files.
2843 if it.peek().is_some() {
2844 write!(w, r#"<div class="example-links">Additional examples can be found in:<br><ul>"#);
2845 it.for_each(|(_, call_data)| {
2846 let (url, _) = link_to_loc(&call_data, &call_data.locations[0]);
2849 r#"<li><a href="{url}">{name}</a></li>"#,
2851 name = call_data.display_name
2854 write!(w, "</ul></div>");
2857 write!(w, "</div></div></details>");
2860 write!(w, "</div>");