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;
47 use std::string::ToString;
49 use rustc_ast_pretty::pprust;
50 use rustc_attr::{ConstStability, Deprecation, StabilityLevel};
51 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
52 use rustc_hir::def::CtorKind;
53 use rustc_hir::def_id::DefId;
54 use rustc_hir::Mutability;
55 use rustc_middle::middle::stability;
57 use rustc_middle::ty::TyCtxt;
59 symbol::{kw, sym, Symbol},
60 BytePos, FileName, RealFileName,
62 use serde::ser::SerializeSeq;
63 use serde::{Serialize, Serializer};
65 use crate::clean::{self, ItemId, RenderedLink, SelfTy};
66 use crate::error::Error;
67 use crate::formats::cache::Cache;
68 use crate::formats::item_type::ItemType;
69 use crate::formats::{AssocItemRender, Impl, RenderMode};
70 use crate::html::escape::Escape;
71 use crate::html::format::{
72 href, join_with_double_colon, print_abi_with_space, print_constness_with_space,
73 print_default_space, print_generic_bounds, print_where_clause, Buffer, HrefError,
76 use crate::html::highlight;
77 use crate::html::markdown::{HeadingOffset, IdMap, Markdown, MarkdownHtml, MarkdownSummaryLine};
78 use crate::html::sources;
79 use crate::html::static_files::SCRAPE_EXAMPLES_HELP_MD;
80 use crate::scrape_examples::{CallData, CallLocation};
82 use crate::DOC_RUST_LANG_ORG_CHANNEL;
84 /// A pair of name and its optional document.
85 pub(crate) type NameDoc = (String, Option<String>);
87 pub(crate) fn ensure_trailing_slash(v: &str) -> impl fmt::Display + '_ {
88 crate::html::format::display_fn(move |f| {
89 if !v.ends_with('/') && !v.is_empty() { write!(f, "{}/", v) } else { f.write_str(v) }
93 // Helper structs for rendering items/sidebars and carrying along contextual
96 /// Struct representing one entry in the JS search index. These are all emitted
97 /// by hand to a large JS file at the end of cache-creation.
99 pub(crate) struct IndexItem {
100 pub(crate) ty: ItemType,
101 pub(crate) name: String,
102 pub(crate) path: String,
103 pub(crate) desc: String,
104 pub(crate) parent: Option<DefId>,
105 pub(crate) parent_idx: Option<usize>,
106 pub(crate) search_type: Option<IndexItemFunctionType>,
107 pub(crate) aliases: Box<[Symbol]>,
110 /// A type used for the search index.
112 pub(crate) struct RenderType {
113 name: Option<String>,
114 generics: Option<Vec<TypeWithKind>>,
117 /// Full type of functions/methods in the search index.
119 pub(crate) struct IndexItemFunctionType {
120 inputs: Vec<TypeWithKind>,
121 output: Vec<TypeWithKind>,
124 impl Serialize for IndexItemFunctionType {
125 fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
129 // If we couldn't figure out a type, just write `null`.
130 let has_missing = self.inputs.iter().chain(self.output.iter()).any(|i| i.ty.name.is_none());
132 serializer.serialize_none()
134 let mut seq = serializer.serialize_seq(None)?;
135 seq.serialize_element(&self.inputs)?;
136 match self.output.as_slice() {
138 [one] => seq.serialize_element(one)?,
139 all => seq.serialize_element(all)?,
147 pub(crate) struct TypeWithKind {
152 impl From<(RenderType, ItemType)> for TypeWithKind {
153 fn from(x: (RenderType, ItemType)) -> TypeWithKind {
154 TypeWithKind { ty: x.0, kind: x.1 }
158 impl Serialize for TypeWithKind {
159 fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
163 let mut seq = serializer.serialize_seq(None)?;
164 seq.serialize_element(&self.ty.name)?;
165 seq.serialize_element(&self.kind)?;
166 if let Some(generics) = &self.ty.generics {
167 seq.serialize_element(generics)?;
173 #[derive(Debug, Clone)]
174 pub(crate) struct StylePath {
175 /// The path to the theme
176 pub(crate) path: PathBuf,
180 pub(crate) fn basename(&self) -> Result<String, Error> {
181 Ok(try_none!(try_none!(self.path.file_stem(), &self.path).to_str(), &self.path).to_string())
185 fn write_srclink(cx: &Context<'_>, item: &clean::Item, buf: &mut Buffer) {
186 if let Some(l) = cx.src_href(item) {
187 write!(buf, "<a class=\"srclink\" href=\"{}\">source</a>", l)
191 #[derive(Debug, Eq, PartialEq, Hash)]
198 fn new(mut url: String, name: String) -> ItemEntry {
199 while url.starts_with('/') {
202 ItemEntry { url, name }
207 pub(crate) fn print(&self) -> impl fmt::Display + '_ {
208 crate::html::format::display_fn(move |f| {
209 write!(f, "<a href=\"{}\">{}</a>", self.url, Escape(&self.name))
214 impl PartialOrd for ItemEntry {
215 fn partial_cmp(&self, other: &ItemEntry) -> Option<::std::cmp::Ordering> {
216 Some(self.cmp(other))
220 impl Ord for ItemEntry {
221 fn cmp(&self, other: &ItemEntry) -> ::std::cmp::Ordering {
222 self.name.cmp(&other.name)
228 structs: FxHashSet<ItemEntry>,
229 enums: FxHashSet<ItemEntry>,
230 unions: FxHashSet<ItemEntry>,
231 primitives: FxHashSet<ItemEntry>,
232 traits: FxHashSet<ItemEntry>,
233 macros: FxHashSet<ItemEntry>,
234 functions: FxHashSet<ItemEntry>,
235 typedefs: FxHashSet<ItemEntry>,
236 opaque_tys: FxHashSet<ItemEntry>,
237 statics: FxHashSet<ItemEntry>,
238 constants: FxHashSet<ItemEntry>,
239 attributes: FxHashSet<ItemEntry>,
240 derives: FxHashSet<ItemEntry>,
241 trait_aliases: FxHashSet<ItemEntry>,
245 fn new() -> AllTypes {
246 let new_set = |cap| FxHashSet::with_capacity_and_hasher(cap, Default::default());
248 structs: new_set(100),
250 unions: new_set(100),
251 primitives: new_set(26),
252 traits: new_set(100),
253 macros: new_set(100),
254 functions: new_set(100),
255 typedefs: new_set(100),
256 opaque_tys: new_set(100),
257 statics: new_set(100),
258 constants: new_set(100),
259 attributes: new_set(100),
260 derives: new_set(100),
261 trait_aliases: new_set(100),
265 fn append(&mut self, item_name: String, item_type: &ItemType) {
266 let mut url: Vec<_> = item_name.split("::").skip(1).collect();
267 if let Some(name) = url.pop() {
268 let new_url = format!("{}/{}.{}.html", url.join("/"), item_type, name);
270 let name = url.join("::");
272 ItemType::Struct => self.structs.insert(ItemEntry::new(new_url, name)),
273 ItemType::Enum => self.enums.insert(ItemEntry::new(new_url, name)),
274 ItemType::Union => self.unions.insert(ItemEntry::new(new_url, name)),
275 ItemType::Primitive => self.primitives.insert(ItemEntry::new(new_url, name)),
276 ItemType::Trait => self.traits.insert(ItemEntry::new(new_url, name)),
277 ItemType::Macro => self.macros.insert(ItemEntry::new(new_url, name)),
278 ItemType::Function => self.functions.insert(ItemEntry::new(new_url, name)),
279 ItemType::Typedef => self.typedefs.insert(ItemEntry::new(new_url, name)),
280 ItemType::OpaqueTy => self.opaque_tys.insert(ItemEntry::new(new_url, name)),
281 ItemType::Static => self.statics.insert(ItemEntry::new(new_url, name)),
282 ItemType::Constant => self.constants.insert(ItemEntry::new(new_url, name)),
283 ItemType::ProcAttribute => self.attributes.insert(ItemEntry::new(new_url, name)),
284 ItemType::ProcDerive => self.derives.insert(ItemEntry::new(new_url, name)),
285 ItemType::TraitAlias => self.trait_aliases.insert(ItemEntry::new(new_url, name)),
293 fn print(self, f: &mut Buffer) {
294 fn print_entries(f: &mut Buffer, e: &FxHashSet<ItemEntry>, title: &str, class: &str) {
296 let mut e: Vec<&ItemEntry> = e.iter().collect();
300 "<h3 id=\"{}\">{}</h3><ul class=\"{} docblock\">",
301 title.replace(' ', "-"), // IDs cannot contain whitespaces.
307 write!(f, "<li>{}</li>", s.print());
310 f.write_str("</ul>");
316 <span class=\"in-band\">List of all items</span>\
319 // Note: print_entries does not escape the title, because we know the current set of titles
320 // doesn't require escaping.
321 print_entries(f, &self.structs, "Structs", "structs");
322 print_entries(f, &self.enums, "Enums", "enums");
323 print_entries(f, &self.unions, "Unions", "unions");
324 print_entries(f, &self.primitives, "Primitives", "primitives");
325 print_entries(f, &self.traits, "Traits", "traits");
326 print_entries(f, &self.macros, "Macros", "macros");
327 print_entries(f, &self.attributes, "Attribute Macros", "attributes");
328 print_entries(f, &self.derives, "Derive Macros", "derives");
329 print_entries(f, &self.functions, "Functions", "functions");
330 print_entries(f, &self.typedefs, "Typedefs", "typedefs");
331 print_entries(f, &self.trait_aliases, "Trait Aliases", "trait-aliases");
332 print_entries(f, &self.opaque_tys, "Opaque Types", "opaque-types");
333 print_entries(f, &self.statics, "Statics", "statics");
334 print_entries(f, &self.constants, "Constants", "constants")
338 fn scrape_examples_help(shared: &SharedContext<'_>) -> String {
339 let mut content = SCRAPE_EXAMPLES_HELP_MD.to_owned();
340 content.push_str(&format!(
341 "## More information\n\n\
342 If you want more information about this feature, please read the [corresponding chapter in the Rustdoc book]({}/rustdoc/scraped-examples.html).",
343 DOC_RUST_LANG_ORG_CHANNEL));
345 let mut ids = IdMap::default();
347 "<div class=\"main-heading\">\
349 <span class=\"in-band\">About scraped examples</span>\
357 error_codes: shared.codes,
358 edition: shared.edition(),
359 playground: &shared.playground,
360 heading_offset: HeadingOffset::H1
368 cx: &mut Context<'_>,
370 parent: Option<&clean::Item>,
371 heading_offset: HeadingOffset,
373 if let Some(ref name) = item.name {
374 info!("Documenting {}", name);
376 document_item_info(w, cx, item, parent);
377 if parent.is_none() {
378 document_full_collapsible(w, item, cx, heading_offset);
380 document_full(w, item, cx, heading_offset);
384 /// Render md_text as markdown.
387 cx: &mut Context<'_>,
389 links: Vec<RenderedLink>,
390 heading_offset: HeadingOffset,
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.
413 cx: &mut Context<'_>,
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(
442 cx: &mut Context<'_>,
443 heading_offset: HeadingOffset,
445 document_full_inner(w, item, cx, true, heading_offset);
451 cx: &mut Context<'_>,
452 heading_offset: HeadingOffset,
454 document_full_inner(w, item, cx, false, heading_offset);
457 fn document_full_inner(
460 cx: &mut Context<'_>,
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(
496 cx: &mut Context<'_>,
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.
525 cx: &mut Context<'_>,
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 html = MarkdownHtml(
558 &cx.shared.playground,
560 message.push_str(&format!(": {}", html.into_string()));
562 extra_info.push(format!(
563 "<div class=\"stab deprecated\"><span class=\"emoji\">👎</span> {}</div>",
568 // Render unstable items. But don't render "rustc_private" crates (internal compiler crates).
569 // Those crates are permanently unstable so it makes no sense to render "unstable" everywhere.
570 if let Some((StabilityLevel::Unstable { reason: _, issue, .. }, feature)) = item
573 .filter(|stab| stab.feature != sym::rustc_private)
574 .map(|stab| (stab.level, stab.feature))
577 "<span class=\"emoji\">🔬</span> This is a nightly-only experimental API.".to_owned();
579 let mut feature = format!("<code>{}</code>", Escape(feature.as_str()));
580 if let (Some(url), Some(issue)) = (&cx.shared.issue_tracker_base_url, issue) {
581 feature.push_str(&format!(
582 " <a href=\"{url}{issue}\">#{issue}</a>",
588 message.push_str(&format!(" ({})", feature));
590 extra_info.push(format!("<div class=\"stab unstable\">{}</div>", message));
593 if let Some(portability) = portability(item, parent) {
594 extra_info.push(portability);
600 // Render the list of items inside one of the sections "Trait Implementations",
601 // "Auto Trait Implementations," "Blanket Trait Implementations" (on struct/enum pages).
603 cx: &mut Context<'_>,
606 containing_item: &clean::Item,
607 toggle_open_by_default: bool,
610 let mut rendered_impls = impls
613 let did = i.trait_did().unwrap();
614 let provided_trait_methods = i.inner_impl().provided_trait_methods(tcx);
615 let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_trait_methods);
616 let mut buffer = if w.is_for_html() { Buffer::html() } else { Buffer::new() };
626 ImplRenderingParameters {
628 is_on_foreign_type: false,
629 show_default_items: true,
630 show_non_assoc_items: true,
631 toggle_open_by_default,
636 .collect::<Vec<_>>();
637 rendered_impls.sort();
638 w.write_str(&rendered_impls.join(""));
641 /// Build a (possibly empty) `href` attribute (a key-value pair) for the given associated item.
642 fn assoc_href_attr(it: &clean::Item, link: AssocItemLink<'_>, cx: &Context<'_>) -> String {
643 let name = it.name.unwrap();
644 let item_type = it.type_();
646 let href = match link {
647 AssocItemLink::Anchor(Some(ref id)) => Some(format!("#{}", id)),
648 AssocItemLink::Anchor(None) => Some(format!("#{}.{}", item_type, name)),
649 AssocItemLink::GotoSource(did, provided_methods) => {
650 // We're creating a link from the implementation of an associated item to its
651 // declaration in the trait declaration.
652 let item_type = match item_type {
653 // For historical but not technical reasons, the item type of methods in
654 // trait declarations depends on whether the method is required (`TyMethod`) or
655 // provided (`Method`).
656 ItemType::Method | ItemType::TyMethod => {
657 if provided_methods.contains(&name) {
663 // For associated types and constants, no such distinction exists.
664 item_type => item_type,
667 match href(did.expect_def_id(), cx) {
668 Ok((url, ..)) => Some(format!("{}#{}.{}", url, item_type, name)),
669 // The link is broken since it points to an external crate that wasn't documented.
670 // Do not create any link in such case. This is better than falling back to a
671 // dummy anchor like `#{item_type}.{name}` representing the `id` of *this* impl item
672 // (that used to happen in older versions). Indeed, in most cases this dummy would
673 // coincide with the `id`. However, it would not always do so.
674 // In general, this dummy would be incorrect:
675 // If the type with the trait impl also had an inherent impl with an assoc. item of
676 // the *same* name as this impl item, the dummy would link to that one even though
677 // those two items are distinct!
678 // In this scenario, the actual `id` of this impl item would be
679 // `#{item_type}.{name}-{n}` for some number `n` (a disambiguator).
680 Err(HrefError::DocumentationNotBuilt) => None,
681 Err(_) => Some(format!("#{}.{}", item_type, name)),
686 // If there is no `href` for the reason explained above, simply do not render it which is valid:
687 // https://html.spec.whatwg.org/multipage/links.html#links-created-by-a-and-area-elements
688 href.map(|href| format!(" href=\"{}\"", href)).unwrap_or_default()
695 default: Option<&clean::ConstantKind>,
696 link: AssocItemLink<'_>,
702 "{extra}{vis}const <a{href} class=\"constant\">{name}</a>: {ty}",
704 vis = it.visibility.print_with_space(it.item_id, cx),
705 href = assoc_href_attr(it, link, cx),
706 name = it.name.as_ref().unwrap(),
709 if let Some(default) = default {
712 // FIXME: `.value()` uses `clean::utils::format_integer_with_underscore_sep` under the
713 // hood which adds noisy underscores and a type suffix to number literals.
714 // This hurts readability in this context especially when more complex expressions
715 // are involved and it doesn't add much of value.
716 // Find a way to print constants here without all that jazz.
717 write!(w, "{}", Escape(&default.value(cx.tcx()).unwrap_or_else(|| default.expr(cx.tcx()))));
724 generics: &clean::Generics,
725 bounds: &[clean::GenericBound],
726 default: Option<&clean::Type>,
727 link: AssocItemLink<'_>,
733 "{indent}type <a{href} class=\"associatedtype\">{name}</a>{generics}",
734 indent = " ".repeat(indent),
735 href = assoc_href_attr(it, link, cx),
736 name = it.name.as_ref().unwrap(),
737 generics = generics.print(cx),
739 if !bounds.is_empty() {
740 write!(w, ": {}", print_generic_bounds(bounds, cx))
742 write!(w, "{}", print_where_clause(generics, cx, indent, false));
743 if let Some(default) = default {
744 write!(w, " = {}", default.print(cx))
753 link: AssocItemLink<'_>,
756 render_mode: RenderMode,
758 let header = meth.fn_header(cx.tcx()).expect("Trying to get header from a non-function item");
759 let name = meth.name.as_ref().unwrap();
760 let vis = meth.visibility.print_with_space(meth.item_id, cx).to_string();
761 // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
763 let constness = match render_mode {
764 RenderMode::Normal => {
765 print_constness_with_space(&header.constness, meth.const_stability(cx.tcx()))
767 RenderMode::ForDeref { .. } => "",
769 let asyncness = header.asyncness.print_with_space();
770 let unsafety = header.unsafety.print_with_space();
771 let defaultness = print_default_space(meth.is_default());
772 let abi = print_abi_with_space(header.abi).to_string();
773 let href = assoc_href_attr(meth, link, cx);
775 // NOTE: `{:#}` does not print HTML formatting, `{}` does. So `g.print` can't be reused between the length calculation and `write!`.
776 let generics_len = format!("{:#}", g.print(cx)).len();
777 let mut header_len = "fn ".len()
784 + name.as_str().len()
787 let (indent, indent_str, end_newline) = if parent == ItemType::Trait {
789 let indent_str = " ";
790 render_attributes_in_pre(w, meth, indent_str);
791 (4, indent_str, false)
793 render_attributes_in_code(w, meth);
796 w.reserve(header_len + "<a href=\"\" class=\"fnname\">{".len() + "</a>".len());
799 "{indent}{vis}{constness}{asyncness}{unsafety}{defaultness}{abi}fn <a{href} class=\"fnname\">{name}</a>\
800 {generics}{decl}{notable_traits}{where_clause}",
803 constness = constness,
804 asyncness = asyncness,
806 defaultness = defaultness,
810 generics = g.print(cx),
811 decl = d.full_print(header_len, indent, header.asyncness, cx),
812 notable_traits = notable_traits_decl(d, cx),
813 where_clause = print_where_clause(g, cx, indent, end_newline),
817 /// Writes a span containing the versions at which an item became stable and/or const-stable. For
818 /// example, if the item became stable at 1.0.0, and const-stable at 1.45.0, this function would
819 /// write a span containing "1.0.0 (const: 1.45.0)".
821 /// Returns `true` if a stability annotation was rendered.
823 /// Stability and const-stability are considered separately. If the item is unstable, no version
824 /// will be written. If the item is const-unstable, "const: unstable" will be appended to the
825 /// span, with a link to the tracking issue if present. If an item's stability or const-stability
826 /// version matches the version of its enclosing item, that version will be omitted.
828 /// Note that it is possible for an unstable function to be const-stable. In that case, the span
829 /// will include the const-stable version, but no stable version will be emitted, as a natural
830 /// consequence of the above rules.
831 fn render_stability_since_raw(
834 const_stability: Option<ConstStability>,
835 containing_ver: Option<Symbol>,
836 containing_const_ver: Option<Symbol>,
838 let stable_version = ver.filter(|inner| !inner.is_empty() && Some(*inner) != containing_ver);
840 let mut title = String::new();
841 let mut stability = String::new();
843 if let Some(ver) = stable_version {
844 stability.push_str(ver.as_str());
845 title.push_str(&format!("Stable since Rust version {}", ver));
848 let const_title_and_stability = match const_stability {
849 Some(ConstStability { level: StabilityLevel::Stable { since }, .. })
850 if Some(since) != containing_const_ver =>
852 Some((format!("const since {}", since), format!("const: {}", since)))
854 Some(ConstStability { level: StabilityLevel::Unstable { issue, .. }, feature, .. }) => {
855 let unstable = if let Some(n) = issue {
857 r#"<a href="https://github.com/rust-lang/rust/issues/{}" title="Tracking issue for {}">unstable</a>"#,
861 String::from("unstable")
864 Some((String::from("const unstable"), format!("const: {}", unstable)))
869 if let Some((const_title, const_stability)) = const_title_and_stability {
870 if !title.is_empty() {
871 title.push_str(&format!(", {}", const_title));
873 title.push_str(&const_title);
876 if !stability.is_empty() {
877 stability.push_str(&format!(" ({})", const_stability));
879 stability.push_str(&const_stability);
883 if !stability.is_empty() {
884 write!(w, r#"<span class="since" title="{}">{}</span>"#, title, stability);
887 !stability.is_empty()
890 fn render_assoc_item(
893 link: AssocItemLink<'_>,
896 render_mode: RenderMode,
899 clean::StrippedItem(..) => {}
900 clean::TyMethodItem(m) => {
901 assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode)
903 clean::MethodItem(m, _) => {
904 assoc_method(w, item, &m.generics, &m.decl, link, parent, cx, render_mode)
906 kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => assoc_const(
911 clean::TyAssocConstItem(_) => None,
912 clean::AssocConstItem(_, default) => Some(default),
916 if parent == ItemType::Trait { " " } else { "" },
919 clean::TyAssocTypeItem(ref generics, ref bounds) => assoc_type(
926 if parent == ItemType::Trait { 4 } else { 0 },
929 clean::AssocTypeItem(ref ty, ref bounds) => assoc_type(
934 Some(ty.item_type.as_ref().unwrap_or(&ty.type_)),
936 if parent == ItemType::Trait { 4 } else { 0 },
939 _ => panic!("render_assoc_item called on non-associated-item"),
943 const ALLOWED_ATTRIBUTES: &[Symbol] =
944 &[sym::export_name, sym::link_section, sym::no_mangle, sym::repr, sym::non_exhaustive];
946 fn attributes(it: &clean::Item) -> Vec<String> {
951 if ALLOWED_ATTRIBUTES.contains(&attr.name_or_empty()) {
953 pprust::attribute_to_string(attr)
965 // When an attribute is rendered inside a `<pre>` tag, it is formatted using
966 // a whitespace prefix and newline.
967 fn render_attributes_in_pre(w: &mut Buffer, it: &clean::Item, prefix: &str) {
968 for a in attributes(it) {
969 writeln!(w, "{}{}", prefix, a);
973 // When an attribute is rendered inside a <code> tag, it is formatted using
974 // a div to produce a newline after it.
975 fn render_attributes_in_code(w: &mut Buffer, it: &clean::Item) {
976 for a in attributes(it) {
977 write!(w, "<div class=\"code-attribute\">{}</div>", a);
981 #[derive(Copy, Clone)]
982 enum AssocItemLink<'a> {
983 Anchor(Option<&'a str>),
984 GotoSource(ItemId, &'a FxHashSet<Symbol>),
987 impl<'a> AssocItemLink<'a> {
988 fn anchor(&self, id: &'a str) -> Self {
990 AssocItemLink::Anchor(_) => AssocItemLink::Anchor(Some(id)),
996 fn render_assoc_items(
998 cx: &mut Context<'_>,
999 containing_item: &clean::Item,
1001 what: AssocItemRender<'_>,
1003 let mut derefs = FxHashSet::default();
1005 render_assoc_items_inner(w, cx, containing_item, it, what, &mut derefs)
1008 fn render_assoc_items_inner(
1010 cx: &mut Context<'_>,
1011 containing_item: &clean::Item,
1013 what: AssocItemRender<'_>,
1014 derefs: &mut FxHashSet<DefId>,
1016 info!("Documenting associated items of {:?}", containing_item.name);
1017 let shared = Rc::clone(&cx.shared);
1018 let cache = &shared.cache;
1019 let Some(v) = cache.impls.get(&it) else { return };
1020 let (non_trait, traits): (Vec<_>, _) = v.iter().partition(|i| i.inner_impl().trait_.is_none());
1021 if !non_trait.is_empty() {
1022 let mut tmp_buf = Buffer::empty_from(w);
1023 let (render_mode, id) = match what {
1024 AssocItemRender::All => {
1026 "<h2 id=\"implementations\" class=\"small-section-header\">\
1028 <a href=\"#implementations\" class=\"anchor\"></a>\
1031 (RenderMode::Normal, "implementations-list".to_owned())
1033 AssocItemRender::DerefFor { trait_, type_, deref_mut_ } => {
1035 cx.derive_id(small_url_encode(format!("deref-methods-{:#}", type_.print(cx))));
1036 if let Some(def_id) = type_.def_id(cx.cache()) {
1037 cx.deref_id_map.insert(def_id, id.clone());
1041 "<h2 id=\"{id}\" class=\"small-section-header\">\
1042 <span>Methods from {trait_}<Target = {type_}></span>\
1043 <a href=\"#{id}\" class=\"anchor\"></a>\
1046 trait_ = trait_.print(cx),
1047 type_ = type_.print(cx),
1049 (RenderMode::ForDeref { mut_: deref_mut_ }, cx.derive_id(id))
1052 let mut impls_buf = Buffer::empty_from(w);
1053 for i in &non_trait {
1059 AssocItemLink::Anchor(None),
1063 ImplRenderingParameters {
1064 show_def_docs: true,
1065 is_on_foreign_type: false,
1066 show_default_items: true,
1067 show_non_assoc_items: true,
1068 toggle_open_by_default: true,
1072 if !impls_buf.is_empty() {
1073 w.push_buffer(tmp_buf);
1074 write!(w, "<div id=\"{}\">", id);
1075 w.push_buffer(impls_buf);
1076 w.write_str("</div>");
1080 if !traits.is_empty() {
1082 traits.iter().find(|t| t.trait_did() == cx.tcx().lang_items().deref_trait());
1083 if let Some(impl_) = deref_impl {
1085 traits.iter().any(|t| t.trait_did() == cx.tcx().lang_items().deref_mut_trait());
1086 render_deref_methods(w, cx, impl_, containing_item, has_deref_mut, derefs);
1089 // If we were already one level into rendering deref methods, we don't want to render
1090 // anything after recursing into any further deref methods above.
1091 if let AssocItemRender::DerefFor { .. } = what {
1095 let (synthetic, concrete): (Vec<&&Impl>, Vec<&&Impl>) =
1096 traits.iter().partition(|t| t.inner_impl().kind.is_auto());
1097 let (blanket_impl, concrete): (Vec<&&Impl>, _) =
1098 concrete.into_iter().partition(|t| t.inner_impl().kind.is_blanket());
1100 let mut impls = Buffer::empty_from(w);
1101 render_impls(cx, &mut impls, &concrete, containing_item, true);
1102 let impls = impls.into_inner();
1103 if !impls.is_empty() {
1106 "<h2 id=\"trait-implementations\" class=\"small-section-header\">\
1107 Trait Implementations\
1108 <a href=\"#trait-implementations\" class=\"anchor\"></a>\
1110 <div id=\"trait-implementations-list\">{}</div>",
1115 if !synthetic.is_empty() {
1117 "<h2 id=\"synthetic-implementations\" class=\"small-section-header\">\
1118 Auto Trait Implementations\
1119 <a href=\"#synthetic-implementations\" class=\"anchor\"></a>\
1121 <div id=\"synthetic-implementations-list\">",
1123 render_impls(cx, w, &synthetic, containing_item, false);
1124 w.write_str("</div>");
1127 if !blanket_impl.is_empty() {
1129 "<h2 id=\"blanket-implementations\" class=\"small-section-header\">\
1130 Blanket Implementations\
1131 <a href=\"#blanket-implementations\" class=\"anchor\"></a>\
1133 <div id=\"blanket-implementations-list\">",
1135 render_impls(cx, w, &blanket_impl, containing_item, false);
1136 w.write_str("</div>");
1141 fn render_deref_methods(
1143 cx: &mut Context<'_>,
1145 container_item: &clean::Item,
1147 derefs: &mut FxHashSet<DefId>,
1149 let cache = cx.cache();
1150 let deref_type = impl_.inner_impl().trait_.as_ref().unwrap();
1151 let (target, real_target) = impl_
1155 .find_map(|item| match *item.kind {
1156 clean::AssocTypeItem(ref t, _) => Some(match *t {
1157 clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
1158 _ => (&t.type_, &t.type_),
1162 .expect("Expected associated type binding");
1163 debug!("Render deref methods for {:#?}, target {:#?}", impl_.inner_impl().for_, target);
1165 AssocItemRender::DerefFor { trait_: deref_type, type_: real_target, deref_mut_: deref_mut };
1166 if let Some(did) = target.def_id(cache) {
1167 if let Some(type_did) = impl_.inner_impl().for_.def_id(cache) {
1168 // `impl Deref<Target = S> for S`
1169 if did == type_did || !derefs.insert(did) {
1170 // Avoid infinite cycles
1174 render_assoc_items_inner(w, cx, container_item, did, what, derefs);
1175 } else if let Some(prim) = target.primitive_type() {
1176 if let Some(&did) = cache.primitive_locations.get(&prim) {
1177 render_assoc_items_inner(w, cx, container_item, did, what, derefs);
1182 fn should_render_item(item: &clean::Item, deref_mut_: bool, tcx: TyCtxt<'_>) -> bool {
1183 let self_type_opt = match *item.kind {
1184 clean::MethodItem(ref method, _) => method.decl.self_type(),
1185 clean::TyMethodItem(ref method) => method.decl.self_type(),
1189 if let Some(self_ty) = self_type_opt {
1190 let (by_mut_ref, by_box, by_value) = match self_ty {
1191 SelfTy::SelfBorrowed(_, mutability)
1192 | SelfTy::SelfExplicit(clean::BorrowedRef { mutability, .. }) => {
1193 (mutability == Mutability::Mut, false, false)
1195 SelfTy::SelfExplicit(clean::Type::Path { path }) => {
1196 (false, Some(path.def_id()) == tcx.lang_items().owned_box(), false)
1198 SelfTy::SelfValue => (false, false, true),
1199 _ => (false, false, false),
1202 (deref_mut_ || !by_mut_ref) && !by_box && !by_value
1208 fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
1209 let mut out = Buffer::html();
1211 if let Some((did, ty)) = decl.output.as_return().and_then(|t| Some((t.def_id(cx.cache())?, t)))
1213 if let Some(impls) = cx.cache().impls.get(&did) {
1215 let impl_ = i.inner_impl();
1216 if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache())
1218 // Two different types might have the same did,
1219 // without actually being the same.
1222 if let Some(trait_) = &impl_.trait_ {
1223 let trait_did = trait_.def_id();
1225 if cx.cache().traits.get(&trait_did).map_or(false, |t| t.is_notable) {
1229 "<span class=\"notable\">Notable traits for {}</span>\
1230 <code class=\"content\">",
1231 impl_.for_.print(cx)
1235 //use the "where" class here to make it small
1238 "<span class=\"where fmt-newline\">{}</span>",
1239 impl_.print(false, cx)
1241 for it in &impl_.items {
1242 if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
1243 out.push_str("<span class=\"where fmt-newline\"> ");
1244 let empty_set = FxHashSet::default();
1246 AssocItemLink::GotoSource(trait_did.into(), &empty_set);
1251 &[], // intentionally leaving out bounds
1257 out.push_str(";</span>");
1266 if !out.is_empty() {
1269 "<span class=\"notable-traits\"><span class=\"notable-traits-tooltip\">ⓘ\
1270 <span class=\"notable-traits-tooltiptext\"><span class=\"docblock\">",
1272 out.push_str("</code></span></span></span></span>");
1278 #[derive(Clone, Copy, Debug)]
1279 struct ImplRenderingParameters {
1280 show_def_docs: bool,
1281 is_on_foreign_type: bool,
1282 show_default_items: bool,
1283 /// Whether or not to show methods.
1284 show_non_assoc_items: bool,
1285 toggle_open_by_default: bool,
1290 cx: &mut Context<'_>,
1292 parent: &clean::Item,
1293 link: AssocItemLink<'_>,
1294 render_mode: RenderMode,
1295 use_absolute: Option<bool>,
1297 rendering_params: ImplRenderingParameters,
1299 let shared = Rc::clone(&cx.shared);
1300 let cache = &shared.cache;
1301 let traits = &cache.traits;
1302 let trait_ = i.trait_did().map(|did| &traits[&did]);
1303 let mut close_tags = String::new();
1305 // For trait implementations, the `interesting` output contains all methods that have doc
1306 // comments, and the `boring` output contains all methods that do not. The distinction is
1307 // used to allow hiding the boring methods.
1308 // `containing_item` is used for rendering stability info. If the parent is a trait impl,
1309 // `containing_item` will the grandparent, since trait impls can't have stability attached.
1311 boring: &mut Buffer,
1312 interesting: &mut Buffer,
1313 cx: &mut Context<'_>,
1315 parent: &clean::Item,
1316 containing_item: &clean::Item,
1317 link: AssocItemLink<'_>,
1318 render_mode: RenderMode,
1319 is_default_item: bool,
1320 trait_: Option<&clean::Trait>,
1321 rendering_params: ImplRenderingParameters,
1323 let item_type = item.type_();
1324 let name = item.name.as_ref().unwrap();
1326 let render_method_item = rendering_params.show_non_assoc_items
1327 && match render_mode {
1328 RenderMode::Normal => true,
1329 RenderMode::ForDeref { mut_: deref_mut_ } => {
1330 should_render_item(item, deref_mut_, cx.tcx())
1334 let in_trait_class = if trait_.is_some() { " trait-impl" } else { "" };
1336 let mut doc_buffer = Buffer::empty_from(boring);
1337 let mut info_buffer = Buffer::empty_from(boring);
1338 let mut short_documented = true;
1340 if render_method_item {
1341 if !is_default_item {
1342 if let Some(t) = trait_ {
1343 // The trait item may have been stripped so we might not
1344 // find any documentation or stability for it.
1345 if let Some(it) = t.items.iter().find(|i| i.name == item.name) {
1346 // We need the stability of the item from the trait
1347 // because impls can't have a stability.
1348 if item.doc_value().is_some() {
1349 document_item_info(&mut info_buffer, cx, it, Some(parent));
1350 document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
1351 short_documented = false;
1353 // In case the item isn't documented,
1354 // provide short documentation from the trait.
1361 rendering_params.show_def_docs,
1366 document_item_info(&mut info_buffer, cx, item, Some(parent));
1367 if rendering_params.show_def_docs {
1368 document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
1369 short_documented = false;
1379 rendering_params.show_def_docs,
1383 let w = if short_documented && trait_.is_some() { interesting } else { boring };
1385 let toggled = !doc_buffer.is_empty();
1387 let method_toggle_class =
1388 if item_type == ItemType::Method { " method-toggle" } else { "" };
1389 write!(w, "<details class=\"rustdoc-toggle{}\" open><summary>", method_toggle_class);
1392 clean::MethodItem(..) | clean::TyMethodItem(_) => {
1393 // Only render when the method is not static or we allow static methods
1394 if render_method_item {
1395 let id = cx.derive_id(format!("{}.{}", item_type, name));
1396 let source_id = trait_
1397 .and_then(|trait_| {
1398 trait_.items.iter().find(|item| {
1399 item.name.map(|n| n.as_str().eq(name.as_str())).unwrap_or(false)
1402 .map(|item| format!("{}.{}", item.type_(), name));
1405 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1406 id, item_type, in_trait_class,
1408 render_rightside(w, cx, item, containing_item, render_mode);
1409 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1410 w.write_str("<h4 class=\"code-header\">");
1414 link.anchor(source_id.as_ref().unwrap_or(&id)),
1419 w.write_str("</h4>");
1420 w.write_str("</section>");
1423 kind @ (clean::TyAssocConstItem(ty) | clean::AssocConstItem(ty, _)) => {
1424 let source_id = format!("{}.{}", item_type, name);
1425 let id = cx.derive_id(source_id.clone());
1428 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1429 id, item_type, in_trait_class
1431 render_rightside(w, cx, item, containing_item, render_mode);
1432 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1433 w.write_str("<h4 class=\"code-header\">");
1439 clean::TyAssocConstItem(_) => None,
1440 clean::AssocConstItem(_, default) => Some(default),
1441 _ => unreachable!(),
1443 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1447 w.write_str("</h4>");
1448 w.write_str("</section>");
1450 clean::TyAssocTypeItem(generics, bounds) => {
1451 let source_id = format!("{}.{}", item_type, name);
1452 let id = cx.derive_id(source_id.clone());
1453 write!(w, "<section id=\"{}\" class=\"{}{}\">", id, item_type, in_trait_class);
1454 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1455 w.write_str("<h4 class=\"code-header\">");
1462 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1466 w.write_str("</h4>");
1467 w.write_str("</section>");
1469 clean::AssocTypeItem(tydef, _bounds) => {
1470 let source_id = format!("{}.{}", item_type, name);
1471 let id = cx.derive_id(source_id.clone());
1474 "<section id=\"{}\" class=\"{}{} has-srclink\">",
1475 id, item_type, in_trait_class
1477 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1478 w.write_str("<h4 class=\"code-header\">");
1483 &[], // intentionally leaving out bounds
1484 Some(tydef.item_type.as_ref().unwrap_or(&tydef.type_)),
1485 link.anchor(if trait_.is_some() { &source_id } else { &id }),
1489 w.write_str("</h4>");
1490 w.write_str("</section>");
1492 clean::StrippedItem(..) => return,
1493 _ => panic!("can't make docs for trait item with name {:?}", item.name),
1496 w.push_buffer(info_buffer);
1498 w.write_str("</summary>");
1499 w.push_buffer(doc_buffer);
1500 w.push_str("</details>");
1504 let mut impl_items = Buffer::empty_from(w);
1505 let mut default_impl_items = Buffer::empty_from(w);
1507 for trait_item in &i.inner_impl().items {
1509 &mut default_impl_items,
1513 if trait_.is_some() { &i.impl_item } else { parent },
1518 trait_.map(|t| &t.trait_),
1523 fn render_default_items(
1524 boring: &mut Buffer,
1525 interesting: &mut Buffer,
1526 cx: &mut Context<'_>,
1529 parent: &clean::Item,
1530 containing_item: &clean::Item,
1531 render_mode: RenderMode,
1532 rendering_params: ImplRenderingParameters,
1534 for trait_item in &t.items {
1535 let n = trait_item.name;
1536 if i.items.iter().any(|m| m.name == n) {
1539 let did = i.trait_.as_ref().unwrap().def_id();
1540 let provided_methods = i.provided_trait_methods(cx.tcx());
1541 let assoc_link = AssocItemLink::GotoSource(did.into(), &provided_methods);
1559 // If we've implemented a trait, then also emit documentation for all
1560 // default items which weren't overridden in the implementation block.
1561 // We don't emit documentation for default items if they appear in the
1562 // Implementations on Foreign Types or Implementors sections.
1563 if rendering_params.show_default_items {
1564 if let Some(t) = trait_ {
1565 render_default_items(
1566 &mut default_impl_items,
1578 if render_mode == RenderMode::Normal {
1579 let toggled = !(impl_items.is_empty() && default_impl_items.is_empty());
1581 close_tags.insert_str(0, "</details>");
1584 "<details class=\"rustdoc-toggle implementors-toggle\"{}>",
1585 if rendering_params.toggle_open_by_default { " open" } else { "" }
1587 write!(w, "<summary>")
1589 render_impl_summary(
1595 rendering_params.show_def_docs,
1597 rendering_params.is_on_foreign_type,
1601 write!(w, "</summary>")
1604 if let Some(ref dox) = i.impl_item.collapsed_doc_value() {
1605 if trait_.is_none() && i.inner_impl().items.is_empty() {
1607 "<div class=\"item-info\">\
1608 <div class=\"stab empty-impl\">This impl block contains no items.</div>
1614 "<div class=\"docblock\">{}</div>",
1617 links: &i.impl_item.links(cx),
1618 ids: &mut cx.id_map,
1619 error_codes: cx.shared.codes,
1620 edition: cx.shared.edition(),
1621 playground: &cx.shared.playground,
1622 heading_offset: HeadingOffset::H4
1628 if !default_impl_items.is_empty() || !impl_items.is_empty() {
1629 w.write_str("<div class=\"impl-items\">");
1630 w.push_buffer(default_impl_items);
1631 w.push_buffer(impl_items);
1632 close_tags.insert_str(0, "</div>");
1634 w.write_str(&close_tags);
1637 // Render the items that appear on the right side of methods, impls, and
1638 // associated types. For example "1.0.0 (const: 1.39.0) · source".
1639 fn render_rightside(
1643 containing_item: &clean::Item,
1644 render_mode: RenderMode,
1648 // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
1650 let (const_stability, const_stable_since) = match render_mode {
1651 RenderMode::Normal => (item.const_stability(tcx), containing_item.const_stable_since(tcx)),
1652 RenderMode::ForDeref { .. } => (None, None),
1655 let mut rightside = Buffer::new();
1656 let has_stability = render_stability_since_raw(
1658 item.stable_since(tcx),
1660 containing_item.stable_since(tcx),
1663 let mut srclink = Buffer::empty_from(w);
1664 write_srclink(cx, item, &mut srclink);
1665 if has_stability && !srclink.is_empty() {
1666 rightside.write_str(" · ");
1668 rightside.push_buffer(srclink);
1669 if !rightside.is_empty() {
1670 write!(w, "<span class=\"rightside\">{}</span>", rightside.into_inner());
1674 pub(crate) fn render_impl_summary(
1676 cx: &mut Context<'_>,
1678 parent: &clean::Item,
1679 containing_item: &clean::Item,
1680 show_def_docs: bool,
1681 use_absolute: Option<bool>,
1682 is_on_foreign_type: bool,
1683 // This argument is used to reference same type with different paths to avoid duplication
1684 // in documentation pages for trait with automatic implementations like "Send" and "Sync".
1687 let id = cx.derive_id(match i.inner_impl().trait_ {
1689 if is_on_foreign_type {
1690 get_id_for_impl_on_foreign_type(&i.inner_impl().for_, t, cx)
1692 format!("impl-{}", small_url_encode(format!("{:#}", t.print(cx))))
1695 None => "impl".to_string(),
1697 let aliases = if aliases.is_empty() {
1700 format!(" data-aliases=\"{}\"", aliases.join(","))
1702 write!(w, "<section id=\"{}\" class=\"impl has-srclink\"{}>", id, aliases);
1703 render_rightside(w, cx, &i.impl_item, containing_item, RenderMode::Normal);
1704 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
1705 write!(w, "<h3 class=\"code-header in-band\">");
1707 if let Some(use_absolute) = use_absolute {
1708 write!(w, "{}", i.inner_impl().print(use_absolute, cx));
1710 for it in &i.inner_impl().items {
1711 if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
1712 w.write_str("<span class=\"where fmt-newline\"> ");
1717 &[], // intentionally leaving out bounds
1719 AssocItemLink::Anchor(None),
1723 w.write_str(";</span>");
1728 write!(w, "{}", i.inner_impl().print(false, cx));
1732 let is_trait = i.inner_impl().trait_.is_some();
1734 if let Some(portability) = portability(&i.impl_item, Some(parent)) {
1735 write!(w, "<span class=\"item-info\">{}</span>", portability);
1739 w.write_str("</section>");
1742 fn print_sidebar(cx: &Context<'_>, it: &clean::Item, buffer: &mut Buffer) {
1743 let parentlen = cx.current.len() - if it.is_mod() { 1 } else { 0 };
1747 || it.is_primitive()
1755 "<h2 class=\"location\"><a href=\"#\">{}{}</a></h2>",
1757 clean::ModuleItem(..) =>
1765 it.name.as_ref().unwrap()
1769 buffer.write_str("<div class=\"sidebar-elems\">");
1771 write!(buffer, "<div class=\"block\"><ul>");
1772 if let Some(ref version) = cx.cache().crate_version {
1773 write!(buffer, "<li class=\"version\">Version {}</li>", Escape(version));
1775 write!(buffer, "<li><a id=\"all-types\" href=\"all.html\">All Items</a></li>");
1776 buffer.write_str("</ul></div>");
1780 clean::StructItem(ref s) => sidebar_struct(cx, buffer, it, s),
1781 clean::TraitItem(ref t) => sidebar_trait(cx, buffer, it, t),
1782 clean::PrimitiveItem(_) => sidebar_primitive(cx, buffer, it),
1783 clean::UnionItem(ref u) => sidebar_union(cx, buffer, it, u),
1784 clean::EnumItem(ref e) => sidebar_enum(cx, buffer, it, e),
1785 clean::TypedefItem(_) => sidebar_typedef(cx, buffer, it),
1786 clean::ModuleItem(ref m) => sidebar_module(buffer, &m.items),
1787 clean::ForeignTypeItem => sidebar_foreign_type(cx, buffer, it),
1791 // The sidebar is designed to display sibling functions, modules and
1792 // other miscellaneous information. since there are lots of sibling
1793 // items (and that causes quadratic growth in large modules),
1794 // we refactor common parts into a shared JavaScript file per module.
1795 // still, we don't move everything into JS because we want to preserve
1796 // as much HTML as possible in order to allow non-JS-enabled browsers
1797 // to navigate the documentation (though slightly inefficiently).
1800 let path: String = cx.current.iter().map(|s| s.as_str()).intersperse("::").collect();
1802 write!(buffer, "<h2 class=\"location\"><a href=\"index.html\">In {}</a></h2>", path);
1805 // Sidebar refers to the enclosing module, not this module.
1806 let relpath = if it.is_mod() && parentlen != 0 { "./" } else { "" };
1809 "<div id=\"sidebar-vars\" data-name=\"{name}\" data-ty=\"{ty}\" data-relpath=\"{path}\">\
1811 name = it.name.unwrap_or(kw::Empty),
1817 "<script defer src=\"{}sidebar-items{}.js\"></script>",
1818 relpath, cx.shared.resource_suffix
1820 // Closes sidebar-elems div.
1821 buffer.write_str("</div>");
1824 fn get_next_url(used_links: &mut FxHashSet<String>, url: String) -> String {
1825 if used_links.insert(url.clone()) {
1829 while !used_links.insert(format!("{}-{}", url, add)) {
1832 format!("{}-{}", url, add)
1835 struct SidebarLink {
1840 impl fmt::Display for SidebarLink {
1841 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1842 write!(f, "<a href=\"#{}\">{}</a>", self.url, self.name)
1846 impl PartialEq for SidebarLink {
1847 fn eq(&self, other: &Self) -> bool {
1848 self.url == other.url
1852 impl Eq for SidebarLink {}
1854 impl PartialOrd for SidebarLink {
1855 fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
1856 Some(self.cmp(other))
1860 impl Ord for SidebarLink {
1861 fn cmp(&self, other: &Self) -> std::cmp::Ordering {
1862 self.url.cmp(&other.url)
1869 used_links: &mut FxHashSet<String>,
1872 ) -> Vec<SidebarLink> {
1875 .filter_map(|item| match item.name {
1876 Some(name) if !name.is_empty() && item.is_method() => {
1877 if !for_deref || should_render_item(item, deref_mut, tcx) {
1880 url: get_next_url(used_links, format!("{}.{}", ItemType::Method, name)),
1888 .collect::<Vec<_>>()
1891 fn get_associated_constants(
1893 used_links: &mut FxHashSet<String>,
1894 ) -> Vec<SidebarLink> {
1897 .filter_map(|item| match item.name {
1898 Some(name) if !name.is_empty() && item.is_associated_const() => Some(SidebarLink {
1900 url: get_next_url(used_links, format!("{}.{}", ItemType::AssocConst, name)),
1904 .collect::<Vec<_>>()
1907 // The point is to url encode any potential character from a type with genericity.
1908 fn small_url_encode(s: String) -> String {
1909 let mut st = String::new();
1910 let mut last_match = 0;
1911 for (idx, c) in s.char_indices() {
1912 let escaped = match c {
1928 st += &s[last_match..idx];
1930 // NOTE: we only expect single byte characters here - which is fine as long as we
1931 // only match single byte characters
1932 last_match = idx + 1;
1935 if last_match != 0 {
1936 st += &s[last_match..];
1943 fn sidebar_assoc_items(cx: &Context<'_>, out: &mut Buffer, it: &clean::Item) {
1944 let did = it.item_id.expect_def_id();
1945 let cache = cx.cache();
1947 if let Some(v) = cache.impls.get(&did) {
1948 let mut used_links = FxHashSet::default();
1949 let mut id_map = IdMap::new();
1952 let used_links_bor = &mut used_links;
1953 let mut assoc_consts = v
1955 .filter(|i| i.inner_impl().trait_.is_none())
1956 .flat_map(|i| get_associated_constants(i.inner_impl(), used_links_bor))
1957 .collect::<Vec<_>>();
1958 if !assoc_consts.is_empty() {
1959 // We want links' order to be reproducible so we don't use unstable sort.
1960 assoc_consts.sort();
1962 print_sidebar_block(
1965 "Associated Constants",
1966 assoc_consts.iter(),
1971 .filter(|i| i.inner_impl().trait_.is_none())
1972 .flat_map(|i| get_methods(i.inner_impl(), false, used_links_bor, false, cx.tcx()))
1973 .collect::<Vec<_>>();
1974 if !methods.is_empty() {
1975 // We want links' order to be reproducible so we don't use unstable sort.
1978 print_sidebar_block(out, "implementations", "Methods", methods.iter());
1982 if v.iter().any(|i| i.inner_impl().trait_.is_some()) {
1983 if let Some(impl_) =
1984 v.iter().find(|i| i.trait_did() == cx.tcx().lang_items().deref_trait())
1986 let mut derefs = FxHashSet::default();
1988 sidebar_deref_methods(cx, out, impl_, v, &mut derefs);
1991 let format_impls = |impls: Vec<&Impl>, id_map: &mut IdMap| {
1992 let mut links = FxHashSet::default();
1997 if let Some(ref i) = it.inner_impl().trait_ {
1998 let i_display = format!("{:#}", i.print(cx));
1999 let out = Escape(&i_display);
2001 id_map.derive(small_url_encode(format!("impl-{:#}", i.print(cx))));
2002 let prefix = match it.inner_impl().polarity {
2003 ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => "",
2004 ty::ImplPolarity::Negative => "!",
2007 format!("<a href=\"#{}\">{}{}</a>", encoded, prefix, out);
2008 if links.insert(generated.clone()) { Some(generated) } else { None }
2013 .collect::<Vec<String>>();
2018 let (synthetic, concrete): (Vec<&Impl>, Vec<&Impl>) =
2019 v.iter().partition::<Vec<_>, _>(|i| i.inner_impl().kind.is_auto());
2020 let (blanket_impl, concrete): (Vec<&Impl>, Vec<&Impl>) =
2021 concrete.into_iter().partition::<Vec<_>, _>(|i| i.inner_impl().kind.is_blanket());
2023 let concrete_format = format_impls(concrete, &mut id_map);
2024 let synthetic_format = format_impls(synthetic, &mut id_map);
2025 let blanket_format = format_impls(blanket_impl, &mut id_map);
2027 if !concrete_format.is_empty() {
2028 print_sidebar_block(
2030 "trait-implementations",
2031 "Trait Implementations",
2032 concrete_format.iter(),
2036 if !synthetic_format.is_empty() {
2037 print_sidebar_block(
2039 "synthetic-implementations",
2040 "Auto Trait Implementations",
2041 synthetic_format.iter(),
2045 if !blanket_format.is_empty() {
2046 print_sidebar_block(
2048 "blanket-implementations",
2049 "Blanket Implementations",
2050 blanket_format.iter(),
2057 fn sidebar_deref_methods(
2062 derefs: &mut FxHashSet<DefId>,
2066 debug!("found Deref: {:?}", impl_);
2067 if let Some((target, real_target)) =
2068 impl_.inner_impl().items.iter().find_map(|item| match *item.kind {
2069 clean::AssocTypeItem(ref t, _) => Some(match *t {
2070 clean::Typedef { item_type: Some(ref type_), .. } => (type_, &t.type_),
2071 _ => (&t.type_, &t.type_),
2076 debug!("found target, real_target: {:?} {:?}", target, real_target);
2077 if let Some(did) = target.def_id(c) {
2078 if let Some(type_did) = impl_.inner_impl().for_.def_id(c) {
2079 // `impl Deref<Target = S> for S`
2080 if did == type_did || !derefs.insert(did) {
2081 // Avoid infinite cycles
2086 let deref_mut = v.iter().any(|i| i.trait_did() == cx.tcx().lang_items().deref_mut_trait());
2087 let inner_impl = target
2090 target.primitive_type().and_then(|prim| c.primitive_locations.get(&prim).cloned())
2092 .and_then(|did| c.impls.get(&did));
2093 if let Some(impls) = inner_impl {
2094 debug!("found inner_impl: {:?}", impls);
2095 let mut used_links = FxHashSet::default();
2098 .filter(|i| i.inner_impl().trait_.is_none())
2100 get_methods(i.inner_impl(), true, &mut used_links, deref_mut, cx.tcx())
2102 .collect::<Vec<_>>();
2103 if !ret.is_empty() {
2104 let id = if let Some(target_def_id) = real_target.def_id(c) {
2105 cx.deref_id_map.get(&target_def_id).expect("Deref section without derived id")
2109 let title = format!(
2110 "Methods from {}<Target={}>",
2111 Escape(&format!("{:#}", impl_.inner_impl().trait_.as_ref().unwrap().print(cx))),
2112 Escape(&format!("{:#}", real_target.print(cx))),
2114 // We want links' order to be reproducible so we don't use unstable sort.
2116 print_sidebar_block(out, id, &title, ret.iter());
2120 // Recurse into any further impls that might exist for `target`
2121 if let Some(target_did) = target.def_id(c) {
2122 if let Some(target_impls) = c.impls.get(&target_did) {
2123 if let Some(target_deref_impl) = target_impls.iter().find(|i| {
2127 .map(|t| Some(t.def_id()) == cx.tcx().lang_items().deref_trait())
2130 sidebar_deref_methods(cx, out, target_deref_impl, target_impls, derefs);
2137 fn sidebar_struct(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, s: &clean::Struct) {
2138 let mut sidebar = Buffer::new();
2139 let fields = get_struct_fields_name(&s.fields);
2141 if !fields.is_empty() {
2142 match s.struct_type {
2143 CtorKind::Fictive => {
2144 print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
2146 CtorKind::Fn => print_sidebar_title(&mut sidebar, "fields", "Tuple Fields"),
2147 CtorKind::Const => {}
2151 sidebar_assoc_items(cx, &mut sidebar, it);
2153 if !sidebar.is_empty() {
2154 write!(buf, "<section>{}</section>", sidebar.into_inner());
2158 fn get_id_for_impl_on_foreign_type(
2160 trait_: &clean::Path,
2163 small_url_encode(format!("impl-{:#}-for-{:#}", trait_.print(cx), for_.print(cx)))
2166 fn extract_for_impl_name(item: &clean::Item, cx: &Context<'_>) -> Option<(String, String)> {
2168 clean::ItemKind::ImplItem(ref i) => {
2169 i.trait_.as_ref().map(|trait_| {
2170 // Alternative format produces no URLs,
2171 // so this parameter does nothing.
2173 format!("{:#}", i.for_.print(cx)),
2174 get_id_for_impl_on_foreign_type(&i.for_, trait_, cx),
2182 /// Don't call this function directly!!! Use `print_sidebar_title` or `print_sidebar_block` instead!
2183 fn print_sidebar_title_inner(buf: &mut Buffer, id: &str, title: &str) {
2186 "<h3 class=\"sidebar-title\">\
2187 <a href=\"#{}\">{}</a>\
2193 fn print_sidebar_title(buf: &mut Buffer, id: &str, title: &str) {
2194 buf.push_str("<div class=\"block\">");
2195 print_sidebar_title_inner(buf, id, title);
2196 buf.push_str("</div>");
2199 fn print_sidebar_block(
2203 items: impl Iterator<Item = impl fmt::Display>,
2205 buf.push_str("<div class=\"block\">");
2206 print_sidebar_title_inner(buf, id, title);
2207 buf.push_str("<ul>");
2209 write!(buf, "<li>{}</li>", item);
2211 buf.push_str("</ul></div>");
2214 fn sidebar_trait(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, t: &clean::Trait) {
2215 buf.write_str("<section>");
2217 fn print_sidebar_section(
2219 items: &[clean::Item],
2222 filter: impl Fn(&clean::Item) -> bool,
2223 mapper: impl Fn(&str) -> String,
2225 let mut items: Vec<&str> = items
2227 .filter_map(|m| match m.name {
2228 Some(ref name) if filter(m) => Some(name.as_str()),
2231 .collect::<Vec<_>>();
2233 if !items.is_empty() {
2234 items.sort_unstable();
2235 print_sidebar_block(out, id, title, items.into_iter().map(mapper));
2239 print_sidebar_section(
2242 "required-associated-types",
2243 "Required Associated Types",
2244 |m| m.is_ty_associated_type(),
2245 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocType),
2248 print_sidebar_section(
2251 "provided-associated-types",
2252 "Provided Associated Types",
2253 |m| m.is_associated_type(),
2254 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocType),
2257 print_sidebar_section(
2260 "required-associated-consts",
2261 "Required Associated Constants",
2262 |m| m.is_ty_associated_const(),
2263 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocConst),
2266 print_sidebar_section(
2269 "provided-associated-consts",
2270 "Provided Associated Constants",
2271 |m| m.is_associated_const(),
2272 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::AssocConst),
2275 print_sidebar_section(
2280 |m| m.is_ty_method(),
2281 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::TyMethod),
2284 print_sidebar_section(
2290 |sym| format!("<a href=\"#{1}.{0}\">{0}</a>", sym, ItemType::Method),
2293 if let Some(implementors) = cx.cache().implementors.get(&it.item_id.expect_def_id()) {
2294 let mut res = implementors
2296 .filter(|i| !i.is_on_local_type(cx))
2297 .filter_map(|i| extract_for_impl_name(&i.impl_item, cx))
2298 .collect::<Vec<_>>();
2300 if !res.is_empty() {
2302 print_sidebar_block(
2305 "Implementations on Foreign Types",
2306 res.iter().map(|(name, id)| format!("<a href=\"#{}\">{}</a>", id, Escape(name))),
2311 sidebar_assoc_items(cx, buf, it);
2313 print_sidebar_title(buf, "implementors", "Implementors");
2315 print_sidebar_title(buf, "synthetic-implementors", "Auto Implementors");
2318 buf.push_str("</section>")
2321 fn sidebar_primitive(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2322 let mut sidebar = Buffer::new();
2323 sidebar_assoc_items(cx, &mut sidebar, it);
2325 if !sidebar.is_empty() {
2326 write!(buf, "<section>{}</section>", sidebar.into_inner());
2330 fn sidebar_typedef(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2331 let mut sidebar = Buffer::new();
2332 sidebar_assoc_items(cx, &mut sidebar, it);
2334 if !sidebar.is_empty() {
2335 write!(buf, "<section>{}</section>", sidebar.into_inner());
2339 fn get_struct_fields_name(fields: &[clean::Item]) -> Vec<String> {
2340 let mut fields = fields
2342 .filter(|f| matches!(*f.kind, clean::StructFieldItem(..)))
2344 f.name.map(|name| format!("<a href=\"#structfield.{name}\">{name}</a>", name = name))
2346 .collect::<Vec<_>>();
2351 fn sidebar_union(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, u: &clean::Union) {
2352 let mut sidebar = Buffer::new();
2353 let fields = get_struct_fields_name(&u.fields);
2355 if !fields.is_empty() {
2356 print_sidebar_block(&mut sidebar, "fields", "Fields", fields.iter());
2359 sidebar_assoc_items(cx, &mut sidebar, it);
2361 if !sidebar.is_empty() {
2362 write!(buf, "<section>{}</section>", sidebar.into_inner());
2366 fn sidebar_enum(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item, e: &clean::Enum) {
2367 let mut sidebar = Buffer::new();
2369 let mut variants = e
2374 .map(|name| format!("<a href=\"#variant.{name}\">{name}</a>", name = name))
2376 .collect::<Vec<_>>();
2377 if !variants.is_empty() {
2378 variants.sort_unstable();
2379 print_sidebar_block(&mut sidebar, "variants", "Variants", variants.iter());
2382 sidebar_assoc_items(cx, &mut sidebar, it);
2384 if !sidebar.is_empty() {
2385 write!(buf, "<section>{}</section>", sidebar.into_inner());
2389 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
2409 AssociatedConstants,
2419 const ALL: &'static [Self] = {
2421 // NOTE: The order here affects the order in the UI.
2441 AssociatedConstants,
2451 fn id(self) -> &'static str {
2453 Self::Reexports => "reexports",
2454 Self::Modules => "modules",
2455 Self::Structs => "structs",
2456 Self::Unions => "unions",
2457 Self::Enums => "enums",
2458 Self::Functions => "functions",
2459 Self::TypeDefinitions => "types",
2460 Self::Statics => "statics",
2461 Self::Constants => "constants",
2462 Self::Traits => "traits",
2463 Self::Implementations => "impls",
2464 Self::TypeMethods => "tymethods",
2465 Self::Methods => "methods",
2466 Self::StructFields => "fields",
2467 Self::Variants => "variants",
2468 Self::Macros => "macros",
2469 Self::PrimitiveTypes => "primitives",
2470 Self::AssociatedTypes => "associated-types",
2471 Self::AssociatedConstants => "associated-consts",
2472 Self::ForeignTypes => "foreign-types",
2473 Self::Keywords => "keywords",
2474 Self::OpaqueTypes => "opaque-types",
2475 Self::AttributeMacros => "attributes",
2476 Self::DeriveMacros => "derives",
2477 Self::TraitAliases => "trait-aliases",
2481 fn name(self) -> &'static str {
2483 Self::Reexports => "Re-exports",
2484 Self::Modules => "Modules",
2485 Self::Structs => "Structs",
2486 Self::Unions => "Unions",
2487 Self::Enums => "Enums",
2488 Self::Functions => "Functions",
2489 Self::TypeDefinitions => "Type Definitions",
2490 Self::Statics => "Statics",
2491 Self::Constants => "Constants",
2492 Self::Traits => "Traits",
2493 Self::Implementations => "Implementations",
2494 Self::TypeMethods => "Type Methods",
2495 Self::Methods => "Methods",
2496 Self::StructFields => "Struct Fields",
2497 Self::Variants => "Variants",
2498 Self::Macros => "Macros",
2499 Self::PrimitiveTypes => "Primitive Types",
2500 Self::AssociatedTypes => "Associated Types",
2501 Self::AssociatedConstants => "Associated Constants",
2502 Self::ForeignTypes => "Foreign Types",
2503 Self::Keywords => "Keywords",
2504 Self::OpaqueTypes => "Opaque Types",
2505 Self::AttributeMacros => "Attribute Macros",
2506 Self::DeriveMacros => "Derive Macros",
2507 Self::TraitAliases => "Trait Aliases",
2512 fn item_ty_to_section(ty: ItemType) -> ItemSection {
2514 ItemType::ExternCrate | ItemType::Import => ItemSection::Reexports,
2515 ItemType::Module => ItemSection::Modules,
2516 ItemType::Struct => ItemSection::Structs,
2517 ItemType::Union => ItemSection::Unions,
2518 ItemType::Enum => ItemSection::Enums,
2519 ItemType::Function => ItemSection::Functions,
2520 ItemType::Typedef => ItemSection::TypeDefinitions,
2521 ItemType::Static => ItemSection::Statics,
2522 ItemType::Constant => ItemSection::Constants,
2523 ItemType::Trait => ItemSection::Traits,
2524 ItemType::Impl => ItemSection::Implementations,
2525 ItemType::TyMethod => ItemSection::TypeMethods,
2526 ItemType::Method => ItemSection::Methods,
2527 ItemType::StructField => ItemSection::StructFields,
2528 ItemType::Variant => ItemSection::Variants,
2529 ItemType::Macro => ItemSection::Macros,
2530 ItemType::Primitive => ItemSection::PrimitiveTypes,
2531 ItemType::AssocType => ItemSection::AssociatedTypes,
2532 ItemType::AssocConst => ItemSection::AssociatedConstants,
2533 ItemType::ForeignType => ItemSection::ForeignTypes,
2534 ItemType::Keyword => ItemSection::Keywords,
2535 ItemType::OpaqueTy => ItemSection::OpaqueTypes,
2536 ItemType::ProcAttribute => ItemSection::AttributeMacros,
2537 ItemType::ProcDerive => ItemSection::DeriveMacros,
2538 ItemType::TraitAlias => ItemSection::TraitAliases,
2539 ItemType::Generic => unreachable!(),
2543 fn sidebar_module(buf: &mut Buffer, items: &[clean::Item]) {
2544 use std::fmt::Write as _;
2546 let mut sidebar = String::new();
2548 let item_sections_in_use: FxHashSet<_> = items
2555 if let clean::ImportItem(ref i) = *it.kind &&
2556 let clean::ImportKind::Simple(s) = i.kind { Some(s) } else { None }
2560 .map(|it| item_ty_to_section(it.type_()))
2562 for &sec in ItemSection::ALL.iter().filter(|sec| item_sections_in_use.contains(sec)) {
2563 let _ = write!(sidebar, "<li><a href=\"#{}\">{}</a></li>", sec.id(), sec.name());
2566 if !sidebar.is_empty() {
2570 <div class=\"block\">\
2579 fn sidebar_foreign_type(cx: &Context<'_>, buf: &mut Buffer, it: &clean::Item) {
2580 let mut sidebar = Buffer::new();
2581 sidebar_assoc_items(cx, &mut sidebar, it);
2583 if !sidebar.is_empty() {
2584 write!(buf, "<section>{}</section>", sidebar.into_inner());
2588 pub(crate) const BASIC_KEYWORDS: &str = "rust, rustlang, rust-lang";
2590 /// Returns a list of all paths used in the type.
2591 /// This is used to help deduplicate imported impls
2592 /// for reexported types. If any of the contained
2593 /// types are re-exported, we don't use the corresponding
2594 /// entry from the js file, as inlining will have already
2595 /// picked up the impl
2596 fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
2597 let mut out = Vec::new();
2598 let mut visited = FxHashSet::default();
2599 let mut work = VecDeque::new();
2601 let mut process_path = |did: DefId| {
2602 let get_extern = || cache.external_paths.get(&did).map(|s| s.0.clone());
2603 let fqp = cache.exact_paths.get(&did).cloned().or_else(get_extern);
2605 if let Some(path) = fqp {
2606 out.push(join_with_double_colon(&path));
2610 work.push_back(first_ty);
2612 while let Some(ty) = work.pop_front() {
2613 if !visited.insert(ty.clone()) {
2618 clean::Type::Path { path } => process_path(path.def_id()),
2619 clean::Type::Tuple(tys) => {
2620 work.extend(tys.into_iter());
2622 clean::Type::Slice(ty) => {
2623 work.push_back(*ty);
2625 clean::Type::Array(ty, _) => {
2626 work.push_back(*ty);
2628 clean::Type::RawPointer(_, ty) => {
2629 work.push_back(*ty);
2631 clean::Type::BorrowedRef { type_, .. } => {
2632 work.push_back(*type_);
2634 clean::Type::QPath { self_type, trait_, .. } => {
2635 work.push_back(*self_type);
2636 process_path(trait_.def_id());
2644 const MAX_FULL_EXAMPLES: usize = 5;
2645 const NUM_VISIBLE_LINES: usize = 10;
2647 /// Generates the HTML for example call locations generated via the --scrape-examples flag.
2648 fn render_call_locations(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item) {
2650 let def_id = item.item_id.expect_def_id();
2651 let key = tcx.def_path_hash(def_id);
2652 let Some(call_locations) = cx.shared.call_locations.get(&key) else { return };
2654 // Generate a unique ID so users can link to this section for a given method
2655 let id = cx.id_map.derive("scraped-examples");
2658 "<div class=\"docblock scraped-example-list\">\
2661 <a href=\"#{id}\">Examples found in repository</a>\
2662 <a class=\"scrape-help\" href=\"{root_path}scrape-examples-help.html\">?</a>\
2664 root_path = cx.root_path(),
2668 // Create a URL to a particular location in a reverse-dependency's source file
2669 let link_to_loc = |call_data: &CallData, loc: &CallLocation| -> (String, String) {
2670 let (line_lo, line_hi) = loc.call_expr.line_span;
2671 let (anchor, title) = if line_lo == line_hi {
2672 ((line_lo + 1).to_string(), format!("line {}", line_lo + 1))
2675 format!("{}-{}", line_lo + 1, line_hi + 1),
2676 format!("lines {}-{}", line_lo + 1, line_hi + 1),
2679 let url = format!("{}{}#{}", cx.root_path(), call_data.url, anchor);
2683 // Generate the HTML for a single example, being the title and code block
2684 let write_example = |w: &mut Buffer, (path, call_data): (&PathBuf, &CallData)| -> bool {
2685 let contents = match fs::read_to_string(&path) {
2686 Ok(contents) => contents,
2688 let span = item.span(tcx).inner();
2690 .span_err(span, &format!("failed to read file {}: {}", path.display(), err));
2695 // To reduce file sizes, we only want to embed the source code needed to understand the example, not
2696 // the entire file. So we find the smallest byte range that covers all items enclosing examples.
2697 assert!(!call_data.locations.is_empty());
2699 call_data.locations.iter().min_by_key(|loc| loc.enclosing_item.byte_span.0).unwrap();
2700 let byte_min = min_loc.enclosing_item.byte_span.0;
2701 let line_min = min_loc.enclosing_item.line_span.0;
2703 call_data.locations.iter().max_by_key(|loc| loc.enclosing_item.byte_span.1).unwrap();
2704 let byte_max = max_loc.enclosing_item.byte_span.1;
2705 let line_max = max_loc.enclosing_item.line_span.1;
2707 // The output code is limited to that byte range.
2708 let contents_subset = &contents[(byte_min as usize)..(byte_max as usize)];
2710 // The call locations need to be updated to reflect that the size of the program has changed.
2711 // Specifically, the ranges are all subtracted by `byte_min` since that's the new zero point.
2712 let (mut byte_ranges, line_ranges): (Vec<_>, Vec<_>) = call_data
2716 let (byte_lo, byte_hi) = loc.call_ident.byte_span;
2717 let (line_lo, line_hi) = loc.call_expr.line_span;
2718 let byte_range = (byte_lo - byte_min, byte_hi - byte_min);
2720 let line_range = (line_lo - line_min, line_hi - line_min);
2721 let (line_url, line_title) = link_to_loc(call_data, loc);
2723 (byte_range, (line_range, line_url, line_title))
2727 let (_, init_url, init_title) = &line_ranges[0];
2728 let needs_expansion = line_max - line_min > NUM_VISIBLE_LINES;
2729 let locations_encoded = serde_json::to_string(&line_ranges).unwrap();
2733 "<div class=\"scraped-example {expanded_cls}\" data-locs=\"{locations}\">\
2734 <div class=\"scraped-example-title\">\
2735 {name} (<a href=\"{url}\">{title}</a>)\
2737 <div class=\"code-wrapper\">",
2738 expanded_cls = if needs_expansion { "" } else { "expanded" },
2739 name = call_data.display_name,
2742 // The locations are encoded as a data attribute, so they can be read
2743 // later by the JS for interactions.
2744 locations = Escape(&locations_encoded)
2747 if line_ranges.len() > 1 {
2748 write!(w, r#"<span class="prev">≺</span> <span class="next">≻</span>"#);
2751 if needs_expansion {
2752 write!(w, r#"<span class="expand">↕</span>"#);
2755 // Look for the example file in the source map if it exists, otherwise return a dummy span
2756 let file_span = (|| {
2757 let source_map = tcx.sess.source_map();
2758 let crate_src = tcx.sess.local_crate_source_file.as_ref()?;
2759 let abs_crate_src = crate_src.canonicalize().ok()?;
2760 let crate_root = abs_crate_src.parent()?.parent()?;
2761 let rel_path = path.strip_prefix(crate_root).ok()?;
2762 let files = source_map.files();
2763 let file = files.iter().find(|file| match &file.name {
2764 FileName::Real(RealFileName::LocalPath(other_path)) => rel_path == other_path,
2767 Some(rustc_span::Span::with_root_ctxt(
2768 file.start_pos + BytePos(byte_min),
2769 file.start_pos + BytePos(byte_max),
2772 .unwrap_or(rustc_span::DUMMY_SP);
2774 // The root path is the inverse of Context::current
2775 let root_path = vec!["../"; cx.current.len() - 1].join("");
2777 let mut decoration_info = FxHashMap::default();
2778 decoration_info.insert("highlight focus", vec![byte_ranges.remove(0)]);
2779 decoration_info.insert("highlight", byte_ranges);
2788 Some(highlight::DecorationInfo(decoration_info)),
2789 sources::SourceContext::Embedded { offset: line_min },
2791 write!(w, "</div></div>");
2796 // The call locations are output in sequence, so that sequence needs to be determined.
2797 // Ideally the most "relevant" examples would be shown first, but there's no general algorithm
2798 // for determining relevance. Instead, we prefer the smallest examples being likely the easiest to
2799 // understand at a glance.
2800 let ordered_locations = {
2801 let sort_criterion = |(_, call_data): &(_, &CallData)| {
2802 // Use the first location because that's what the user will see initially
2803 let (lo, hi) = call_data.locations[0].enclosing_item.byte_span;
2807 let mut locs = call_locations.iter().collect::<Vec<_>>();
2808 locs.sort_by_key(sort_criterion);
2812 let mut it = ordered_locations.into_iter().peekable();
2814 // An example may fail to write if its source can't be read for some reason, so this method
2815 // continues iterating until a write succeeds
2816 let write_and_skip_failure = |w: &mut Buffer, it: &mut Peekable<_>| {
2817 while let Some(example) = it.next() {
2818 if write_example(&mut *w, example) {
2824 // Write just one example that's visible by default in the method's description.
2825 write_and_skip_failure(w, &mut it);
2827 // Then add the remaining examples in a hidden section.
2828 if it.peek().is_some() {
2831 "<details class=\"rustdoc-toggle more-examples-toggle\">\
2832 <summary class=\"hideme\">\
2833 <span>More examples</span>\
2835 <div class=\"hide-more\">Hide additional examples</div>\
2836 <div class=\"more-scraped-examples\">\
2837 <div class=\"toggle-line\"><div class=\"toggle-line-inner\"></div></div>\
2838 <div class=\"more-scraped-examples-inner\">"
2841 // Only generate inline code for MAX_FULL_EXAMPLES number of examples. Otherwise we could
2842 // make the page arbitrarily huge!
2843 for _ in 0..MAX_FULL_EXAMPLES {
2844 write_and_skip_failure(w, &mut it);
2847 // For the remaining examples, generate a <ul> containing links to the source files.
2848 if it.peek().is_some() {
2849 write!(w, r#"<div class="example-links">Additional examples can be found in:<br><ul>"#);
2850 it.for_each(|(_, call_data)| {
2851 let (url, _) = link_to_loc(call_data, &call_data.locations[0]);
2854 r#"<li><a href="{url}">{name}</a></li>"#,
2856 name = call_data.display_name
2859 write!(w, "</ul></div>");
2862 write!(w, "</div></div></details>");
2865 write!(w, "</div>");