1 //! Markdown formatting for rustdoc.
3 //! This module implements markdown formatting through the pulldown-cmark library.
6 //! #![feature(rustc_private)]
8 //! extern crate rustc_span;
10 //! use rustc_span::edition::Edition;
11 //! use rustdoc::html::markdown::{HeadingOffset, IdMap, Markdown, ErrorCodes};
13 //! let s = "My *markdown* _text_";
14 //! let mut id_map = IdMap::new();
15 //! let md = Markdown {
19 //! error_codes: ErrorCodes::Yes,
20 //! edition: Edition::Edition2015,
21 //! playground: &None,
22 //! heading_offset: HeadingOffset::H2,
24 //! let html = md.into_string();
25 //! // ... something using html
28 use rustc_data_structures::fx::FxHashMap;
29 use rustc_hir::def_id::DefId;
31 use rustc_middle::ty::TyCtxt;
32 use rustc_span::edition::Edition;
36 use std::cell::RefCell;
37 use std::collections::VecDeque;
38 use std::default::Default;
40 use std::ops::{ControlFlow, Range};
43 use crate::clean::RenderedLink;
45 use crate::html::escape::Escape;
46 use crate::html::format::Buffer;
47 use crate::html::highlight;
48 use crate::html::length_limit::HtmlWithLimit;
49 use crate::html::toc::TocBuilder;
52 html, BrokenLink, CodeBlockKind, CowStr, Event, LinkType, Options, Parser, Tag,
58 const MAX_HEADER_LEVEL: u32 = 6;
60 /// Options for rendering Markdown in the main body of documentation.
61 pub(crate) fn main_body_opts() -> Options {
62 Options::ENABLE_TABLES
63 | Options::ENABLE_FOOTNOTES
64 | Options::ENABLE_STRIKETHROUGH
65 | Options::ENABLE_TASKLISTS
66 | Options::ENABLE_SMART_PUNCTUATION
69 /// Options for rendering Markdown in summaries (e.g., in search results).
70 pub(crate) fn summary_opts() -> Options {
71 Options::ENABLE_TABLES
72 | Options::ENABLE_FOOTNOTES
73 | Options::ENABLE_STRIKETHROUGH
74 | Options::ENABLE_TASKLISTS
75 | Options::ENABLE_SMART_PUNCTUATION
78 #[derive(Debug, Clone, Copy)]
79 pub enum HeadingOffset {
88 /// When `to_string` is called, this struct will emit the HTML corresponding to
89 /// the rendered version of the contained markdown string.
90 pub struct Markdown<'a> {
92 /// A list of link replacements.
93 pub links: &'a [RenderedLink],
94 /// The current list of used header IDs.
95 pub ids: &'a mut IdMap,
96 /// Whether to allow the use of explicit error codes in doctest lang strings.
97 pub error_codes: ErrorCodes,
98 /// Default edition to use when parsing doctests (to add a `fn main`).
100 pub playground: &'a Option<Playground>,
101 /// Offset at which we render headings.
102 /// E.g. if `heading_offset: HeadingOffset::H2`, then `# something` renders an `<h2>`.
103 pub heading_offset: HeadingOffset,
105 /// A tuple struct like `Markdown` that renders the markdown with a table of contents.
106 crate struct MarkdownWithToc<'a>(
111 crate &'a Option<Playground>,
113 /// A tuple struct like `Markdown` that renders the markdown escaping HTML tags.
114 crate struct MarkdownHtml<'a>(
119 crate &'a Option<Playground>,
121 /// A tuple struct like `Markdown` that renders only the first paragraph.
122 crate struct MarkdownSummaryLine<'a>(pub &'a str, pub &'a [RenderedLink]);
124 #[derive(Copy, Clone, PartialEq, Debug)]
125 pub enum ErrorCodes {
131 crate fn from(b: bool) -> Self {
133 true => ErrorCodes::Yes,
134 false => ErrorCodes::No,
138 crate fn as_bool(self) -> bool {
140 ErrorCodes::Yes => true,
141 ErrorCodes::No => false,
146 /// Controls whether a line will be hidden or shown in HTML output.
148 /// All lines are used in documentation tests.
155 fn for_html(self) -> Option<Cow<'a, str>> {
157 Line::Shown(l) => Some(l),
158 Line::Hidden(_) => None,
162 fn for_code(self) -> Cow<'a, str> {
165 Line::Hidden(l) => Cow::Borrowed(l),
170 // FIXME: There is a minor inconsistency here. For lines that start with ##, we
171 // have no easy way of removing a potential single space after the hashes, which
172 // is done in the single # case. This inconsistency seems okay, if non-ideal. In
173 // order to fix it we'd have to iterate to find the first non-# character, and
174 // then reallocate to remove it; which would make us return a String.
175 fn map_line(s: &str) -> Line<'_> {
176 let trimmed = s.trim();
177 if trimmed.starts_with("##") {
178 Line::Shown(Cow::Owned(s.replacen("##", "#", 1)))
179 } else if let Some(stripped) = trimmed.strip_prefix("# ") {
181 Line::Hidden(stripped)
182 } else if trimmed == "#" {
183 // We cannot handle '#text' because it could be #[attr].
186 Line::Shown(Cow::Borrowed(s))
190 /// Convert chars from a title for an id.
192 /// "Hello, world!" -> "hello-world"
193 fn slugify(c: char) -> Option<char> {
194 if c.is_alphanumeric() || c == '-' || c == '_' {
195 if c.is_ascii() { Some(c.to_ascii_lowercase()) } else { Some(c) }
196 } else if c.is_whitespace() && c.is_ascii() {
203 #[derive(Clone, Debug)]
204 pub struct Playground {
205 pub crate_name: Option<String>,
209 /// Adds syntax highlighting and playground Run buttons to Rust code blocks.
210 struct CodeBlocks<'p, 'a, I: Iterator<Item = Event<'a>>> {
212 check_error_codes: ErrorCodes,
214 // Information about the playground if a URL has been specified, containing an
215 // optional crate name and the URL.
216 playground: &'p Option<Playground>,
219 impl<'p, 'a, I: Iterator<Item = Event<'a>>> CodeBlocks<'p, 'a, I> {
222 error_codes: ErrorCodes,
224 playground: &'p Option<Playground>,
226 CodeBlocks { inner: iter, check_error_codes: error_codes, edition, playground }
230 impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'_, 'a, I> {
231 type Item = Event<'a>;
233 fn next(&mut self) -> Option<Self::Item> {
234 let event = self.inner.next();
239 let kind = if let Some(Event::Start(Tag::CodeBlock(kind))) = event {
245 let mut origtext = String::new();
246 for event in &mut self.inner {
248 Event::End(Tag::CodeBlock(..)) => break,
249 Event::Text(ref s) => {
250 origtext.push_str(s);
255 let lines = origtext.lines().filter_map(|l| map_line(l).for_html());
256 let text = lines.collect::<Vec<Cow<'_, str>>>().join("\n");
258 let parse_result = match kind {
259 CodeBlockKind::Fenced(ref lang) => {
261 LangString::parse_without_check(lang, self.check_error_codes, false);
262 if !parse_result.rust {
263 return Some(Event::Html(
265 "<div class=\"example-wrap\">\
266 <pre class=\"language-{}\"><code>{}</code></pre>\
276 CodeBlockKind::Indented => Default::default(),
279 compile_fail = parse_result.compile_fail;
280 should_panic = parse_result.should_panic;
281 ignore = parse_result.ignore;
282 edition = parse_result.edition;
284 let explicit_edition = edition.is_some();
285 let edition = edition.unwrap_or(self.edition);
287 let playground_button = self.playground.as_ref().and_then(|playground| {
288 let krate = &playground.crate_name;
289 let url = &playground.url;
295 .map(|l| map_line(l).for_code())
296 .collect::<Vec<Cow<'_, str>>>()
298 let krate = krate.as_ref().map(|s| &**s);
300 doctest::make_test(&test, krate, false, &Default::default(), edition, None);
301 let channel = if test.contains("#![feature(") { "&version=nightly" } else { "" };
303 let edition_string = format!("&edition={}", edition);
305 // These characters don't need to be escaped in a URI.
306 // FIXME: use a library function for percent encoding.
307 fn dont_escape(c: u8) -> bool {
308 (b'a' <= c && c <= b'z')
309 || (b'A' <= c && c <= b'Z')
310 || (b'0' <= c && c <= b'9')
321 let mut test_escaped = String::new();
322 for b in test.bytes() {
324 test_escaped.push(char::from(b));
326 write!(test_escaped, "%{:02X}", b).unwrap();
330 r#"<a class="test-arrow" target="_blank" href="{}?code={}{}{}">Run</a>"#,
331 url, test_escaped, channel, edition_string
335 let tooltip = if ignore != Ignore::None {
336 Some((None, "ignore"))
337 } else if compile_fail {
338 Some((None, "compile_fail"))
339 } else if should_panic {
340 Some((None, "should_panic"))
341 } else if explicit_edition {
342 Some((Some(edition), "edition"))
347 // insert newline to clearly separate it from the
348 // previous block so we can shorten the html output
349 let mut s = Buffer::new();
351 highlight::render_with_highlighting(
355 "rust-example-rendered{}",
356 if let Some((_, class)) = tooltip { format!(" {}", class) } else { String::new() }
358 playground_button.as_deref(),
365 Some(Event::Html(s.into_inner().into()))
369 /// Make headings links with anchor IDs and build up TOC.
370 struct LinkReplacer<'a, I: Iterator<Item = Event<'a>>> {
372 links: &'a [RenderedLink],
373 shortcut_link: Option<&'a RenderedLink>,
376 impl<'a, I: Iterator<Item = Event<'a>>> LinkReplacer<'a, I> {
377 fn new(iter: I, links: &'a [RenderedLink]) -> Self {
378 LinkReplacer { inner: iter, links, shortcut_link: None }
382 impl<'a, I: Iterator<Item = Event<'a>>> Iterator for LinkReplacer<'a, I> {
383 type Item = Event<'a>;
385 fn next(&mut self) -> Option<Self::Item> {
386 let mut event = self.inner.next();
388 // Replace intra-doc links and remove disambiguators from shortcut links (`[fn@f]`).
390 // This is a shortcut link that was resolved by the broken_link_callback: `[fn@f]`
391 // Remove any disambiguator.
392 Some(Event::Start(Tag::Link(
393 // [fn@f] or [fn@f][]
394 LinkType::ShortcutUnknown | LinkType::CollapsedUnknown,
398 debug!("saw start of shortcut link to {} with title {}", dest, title);
399 // If this is a shortcut link, it was resolved by the broken_link_callback.
400 // So the URL will already be updated properly.
401 let link = self.links.iter().find(|&link| *link.href == **dest);
402 // Since this is an external iterator, we can't replace the inner text just yet.
403 // Store that we saw a link so we know to replace it later.
404 if let Some(link) = link {
405 trace!("it matched");
406 assert!(self.shortcut_link.is_none(), "shortcut links cannot be nested");
407 self.shortcut_link = Some(link);
410 // Now that we're done with the shortcut link, don't replace any more text.
411 Some(Event::End(Tag::Link(
412 LinkType::ShortcutUnknown | LinkType::CollapsedUnknown,
416 debug!("saw end of shortcut link to {}", dest);
417 if self.links.iter().any(|link| *link.href == **dest) {
418 assert!(self.shortcut_link.is_some(), "saw closing link without opening tag");
419 self.shortcut_link = None;
422 // Handle backticks in inline code blocks, but only if we're in the middle of a shortcut link.
424 Some(Event::Code(text)) => {
425 trace!("saw code {}", text);
426 if let Some(link) = self.shortcut_link {
427 trace!("original text was {}", link.original_text);
428 // NOTE: this only replaces if the code block is the *entire* text.
429 // If only part of the link has code highlighting, the disambiguator will not be removed.
431 // This is a limitation from `collect_intra_doc_links`: it passes a full link,
432 // and does not distinguish at all between code blocks.
433 // So we could never be sure we weren't replacing too much:
434 // [fn@my_`f`unc] is treated the same as [my_func()] in that pass.
436 // NOTE: &[1..len() - 1] is to strip the backticks
437 if **text == link.original_text[1..link.original_text.len() - 1] {
438 debug!("replacing {} with {}", text, link.new_text);
439 *text = CowStr::Borrowed(&link.new_text);
443 // Replace plain text in links, but only in the middle of a shortcut link.
445 Some(Event::Text(text)) => {
446 trace!("saw text {}", text);
447 if let Some(link) = self.shortcut_link {
448 trace!("original text was {}", link.original_text);
449 // NOTE: same limitations as `Event::Code`
450 if **text == *link.original_text {
451 debug!("replacing {} with {}", text, link.new_text);
452 *text = CowStr::Borrowed(&link.new_text);
456 // If this is a link, but not a shortcut link,
457 // replace the URL, since the broken_link_callback was not called.
458 Some(Event::Start(Tag::Link(_, dest, _))) => {
459 if let Some(link) = self.links.iter().find(|&link| *link.original_text == **dest) {
460 *dest = CowStr::Borrowed(link.href.as_ref());
463 // Anything else couldn't have been a valid Rust path, so no need to replace the text.
467 // Yield the modified event
472 /// Wrap HTML tables into `<div>` to prevent having the doc blocks width being too big.
473 struct TableWrapper<'a, I: Iterator<Item = Event<'a>>> {
475 stored_events: VecDeque<Event<'a>>,
478 impl<'a, I: Iterator<Item = Event<'a>>> TableWrapper<'a, I> {
479 fn new(iter: I) -> Self {
480 Self { inner: iter, stored_events: VecDeque::new() }
484 impl<'a, I: Iterator<Item = Event<'a>>> Iterator for TableWrapper<'a, I> {
485 type Item = Event<'a>;
487 fn next(&mut self) -> Option<Self::Item> {
488 if let Some(first) = self.stored_events.pop_front() {
492 let event = self.inner.next()?;
495 Event::Start(Tag::Table(t)) => {
496 self.stored_events.push_back(Event::Start(Tag::Table(t)));
497 Event::Html(CowStr::Borrowed("<div>"))
499 Event::End(Tag::Table(t)) => {
500 self.stored_events.push_back(Event::Html(CowStr::Borrowed("</div>")));
501 Event::End(Tag::Table(t))
508 type SpannedEvent<'a> = (Event<'a>, Range<usize>);
510 /// Make headings links with anchor IDs and build up TOC.
511 struct HeadingLinks<'a, 'b, 'ids, I> {
513 toc: Option<&'b mut TocBuilder>,
514 buf: VecDeque<SpannedEvent<'a>>,
515 id_map: &'ids mut IdMap,
516 heading_offset: HeadingOffset,
519 impl<'a, 'b, 'ids, I> HeadingLinks<'a, 'b, 'ids, I> {
522 toc: Option<&'b mut TocBuilder>,
523 ids: &'ids mut IdMap,
524 heading_offset: HeadingOffset,
526 HeadingLinks { inner: iter, toc, buf: VecDeque::new(), id_map: ids, heading_offset }
530 impl<'a, 'b, 'ids, I: Iterator<Item = SpannedEvent<'a>>> Iterator
531 for HeadingLinks<'a, 'b, 'ids, I>
533 type Item = SpannedEvent<'a>;
535 fn next(&mut self) -> Option<Self::Item> {
536 if let Some(e) = self.buf.pop_front() {
540 let event = self.inner.next();
541 if let Some((Event::Start(Tag::Heading(level, _, _)), _)) = event {
542 let mut id = String::new();
543 for event in &mut self.inner {
545 Event::End(Tag::Heading(..)) => break,
546 Event::Start(Tag::Link(_, _, _)) | Event::End(Tag::Link(..)) => {}
547 Event::Text(text) | Event::Code(text) => {
548 id.extend(text.chars().filter_map(slugify));
549 self.buf.push_back(event);
551 _ => self.buf.push_back(event),
554 let id = self.id_map.derive(id);
556 if let Some(ref mut builder) = self.toc {
557 let mut html_header = String::new();
558 html::push_html(&mut html_header, self.buf.iter().map(|(ev, _)| ev.clone()));
559 let sec = builder.push(level as u32, html_header, id.clone());
560 self.buf.push_front((Event::Html(format!("{} ", sec).into()), 0..0));
564 std::cmp::min(level as u32 + (self.heading_offset as u32), MAX_HEADER_LEVEL);
565 self.buf.push_back((Event::Html(format!("</a></h{}>", level).into()), 0..0));
567 let start_tags = format!(
568 "<h{level} id=\"{id}\" class=\"section-header\">\
573 return Some((Event::Html(start_tags.into()), 0..0));
579 /// Extracts just the first paragraph.
580 struct SummaryLine<'a, I: Iterator<Item = Event<'a>>> {
586 impl<'a, I: Iterator<Item = Event<'a>>> SummaryLine<'a, I> {
587 fn new(iter: I) -> Self {
588 SummaryLine { inner: iter, started: false, depth: 0 }
592 fn check_if_allowed_tag(t: &Tag<'_>) -> bool {
595 Tag::Paragraph | Tag::Item | Tag::Emphasis | Tag::Strong | Tag::Link(..) | Tag::BlockQuote
599 fn is_forbidden_tag(t: &Tag<'_>) -> bool {
600 matches!(t, Tag::CodeBlock(_) | Tag::Table(_) | Tag::TableHead | Tag::TableRow | Tag::TableCell)
603 impl<'a, I: Iterator<Item = Event<'a>>> Iterator for SummaryLine<'a, I> {
604 type Item = Event<'a>;
606 fn next(&mut self) -> Option<Self::Item> {
607 if self.started && self.depth == 0 {
613 if let Some(event) = self.inner.next() {
614 let mut is_start = true;
615 let is_allowed_tag = match event {
616 Event::Start(ref c) => {
617 if is_forbidden_tag(c) {
621 check_if_allowed_tag(c)
623 Event::End(ref c) => {
624 if is_forbidden_tag(c) {
629 check_if_allowed_tag(c)
633 return if !is_allowed_tag {
635 Some(Event::Start(Tag::Paragraph))
637 Some(Event::End(Tag::Paragraph))
647 /// Moves all footnote definitions to the end and add back links to the
649 struct Footnotes<'a, I> {
651 footnotes: FxHashMap<String, (Vec<Event<'a>>, u16)>,
654 impl<'a, I> Footnotes<'a, I> {
655 fn new(iter: I) -> Self {
656 Footnotes { inner: iter, footnotes: FxHashMap::default() }
659 fn get_entry(&mut self, key: &str) -> &mut (Vec<Event<'a>>, u16) {
660 let new_id = self.footnotes.len() + 1;
661 let key = key.to_owned();
662 self.footnotes.entry(key).or_insert((Vec::new(), new_id as u16))
666 impl<'a, I: Iterator<Item = SpannedEvent<'a>>> Iterator for Footnotes<'a, I> {
667 type Item = SpannedEvent<'a>;
669 fn next(&mut self) -> Option<Self::Item> {
671 match self.inner.next() {
672 Some((Event::FootnoteReference(ref reference), range)) => {
673 let entry = self.get_entry(reference);
674 let reference = format!(
675 "<sup id=\"fnref{0}\"><a href=\"#fn{0}\">{0}</a></sup>",
678 return Some((Event::Html(reference.into()), range));
680 Some((Event::Start(Tag::FootnoteDefinition(def)), _)) => {
681 let mut content = Vec::new();
682 for (event, _) in &mut self.inner {
683 if let Event::End(Tag::FootnoteDefinition(..)) = event {
688 let entry = self.get_entry(&def);
689 (*entry).0 = content;
691 Some(e) => return Some(e),
693 if !self.footnotes.is_empty() {
694 let mut v: Vec<_> = self.footnotes.drain().map(|(_, x)| x).collect();
695 v.sort_by(|a, b| a.1.cmp(&b.1));
696 let mut ret = String::from("<div class=\"footnotes\"><hr><ol>");
697 for (mut content, id) in v {
698 write!(ret, "<li id=\"fn{}\">", id).unwrap();
699 let mut is_paragraph = false;
700 if let Some(&Event::End(Tag::Paragraph)) = content.last() {
704 html::push_html(&mut ret, content.into_iter());
705 write!(ret, " <a href=\"#fnref{}\">↩</a>", id).unwrap();
707 ret.push_str("</p>");
709 ret.push_str("</li>");
711 ret.push_str("</ol></div>");
712 return Some((Event::Html(ret.into()), 0..0));
722 crate fn find_testable_code<T: doctest::Tester>(
725 error_codes: ErrorCodes,
726 enable_per_target_ignores: bool,
727 extra_info: Option<&ExtraInfo<'_>>,
729 let mut parser = Parser::new(doc).into_offset_iter();
730 let mut prev_offset = 0;
731 let mut nb_lines = 0;
732 let mut register_header = None;
733 while let Some((event, offset)) = parser.next() {
735 Event::Start(Tag::CodeBlock(kind)) => {
736 let block_info = match kind {
737 CodeBlockKind::Fenced(ref lang) => {
744 enable_per_target_ignores,
749 CodeBlockKind::Indented => Default::default(),
751 if !block_info.rust {
755 let mut test_s = String::new();
757 while let Some((Event::Text(s), _)) = parser.next() {
762 .map(|l| map_line(l).for_code())
763 .collect::<Vec<Cow<'_, str>>>()
766 nb_lines += doc[prev_offset..offset.start].lines().count();
767 // If there are characters between the preceding line ending and
768 // this code block, `str::lines` will return an additional line,
769 // which we subtract here.
770 if nb_lines != 0 && !&doc[prev_offset..offset.start].ends_with('\n') {
773 let line = tests.get_line() + nb_lines + 1;
774 tests.add_test(text, block_info, line);
775 prev_offset = offset.start;
777 Event::Start(Tag::Heading(level, _, _)) => {
778 register_header = Some(level as u32);
780 Event::Text(ref s) if register_header.is_some() => {
781 let level = register_header.unwrap();
783 tests.register_header("", level);
785 tests.register_header(s, level);
787 register_header = None;
794 crate struct ExtraInfo<'tcx> {
805 impl<'tcx> ExtraInfo<'tcx> {
806 crate fn new(tcx: TyCtxt<'tcx>, hir_id: HirId, sp: Span) -> ExtraInfo<'tcx> {
807 ExtraInfo { id: ExtraInfoId::Hir(hir_id), sp, tcx }
810 crate fn new_did(tcx: TyCtxt<'tcx>, did: DefId, sp: Span) -> ExtraInfo<'tcx> {
811 ExtraInfo { id: ExtraInfoId::Def(did), sp, tcx }
814 fn error_invalid_codeblock_attr(&self, msg: &str, help: &str) {
815 let hir_id = match self.id {
816 ExtraInfoId::Hir(hir_id) => hir_id,
817 ExtraInfoId::Def(item_did) => {
818 match item_did.as_local() {
819 Some(item_did) => self.tcx.hir().local_def_id_to_hir_id(item_did),
821 // If non-local, no need to check anything.
827 self.tcx.struct_span_lint_hir(
828 crate::lint::INVALID_CODEBLOCK_ATTRIBUTES,
832 let mut diag = lint.build(msg);
840 #[derive(Eq, PartialEq, Clone, Debug)]
841 crate struct LangString {
843 crate should_panic: bool,
845 crate ignore: Ignore,
847 crate test_harness: bool,
848 crate compile_fail: bool,
849 crate error_codes: Vec<String>,
850 crate allow_fail: bool,
851 crate edition: Option<Edition>,
854 #[derive(Eq, PartialEq, Clone, Debug)]
861 impl Default for LangString {
862 fn default() -> Self {
864 original: String::new(),
867 ignore: Ignore::None,
871 error_codes: Vec::new(),
879 fn parse_without_check(
881 allow_error_code_check: ErrorCodes,
882 enable_per_target_ignores: bool,
884 Self::parse(string, allow_error_code_check, enable_per_target_ignores, None)
887 fn tokens(string: &str) -> impl Iterator<Item = &str> {
888 // Pandoc, which Rust once used for generating documentation,
889 // expects lang strings to be surrounded by `{}` and for each token
890 // to be proceeded by a `.`. Since some of these lang strings are still
891 // loose in the wild, we strip a pair of surrounding `{}` from the lang
892 // string and a leading `.` from each token.
894 let string = string.trim();
896 let first = string.chars().next();
897 let last = string.chars().last();
899 let string = if first == Some('{') && last == Some('}') {
900 &string[1..string.len() - 1]
906 .split(|c| c == ',' || c == ' ' || c == '\t')
908 .map(|token| token.strip_prefix('.').unwrap_or(token))
909 .filter(|token| !token.is_empty())
914 allow_error_code_check: ErrorCodes,
915 enable_per_target_ignores: bool,
916 extra: Option<&ExtraInfo<'_>>,
918 let allow_error_code_check = allow_error_code_check.as_bool();
919 let mut seen_rust_tags = false;
920 let mut seen_other_tags = false;
921 let mut data = LangString::default();
922 let mut ignores = vec![];
924 data.original = string.to_owned();
926 for token in Self::tokens(string) {
929 data.should_panic = true;
930 seen_rust_tags = !seen_other_tags;
934 seen_rust_tags = !seen_other_tags;
937 data.ignore = Ignore::All;
938 seen_rust_tags = !seen_other_tags;
940 x if x.starts_with("ignore-") => {
941 if enable_per_target_ignores {
942 ignores.push(x.trim_start_matches("ignore-").to_owned());
943 seen_rust_tags = !seen_other_tags;
947 data.allow_fail = true;
948 seen_rust_tags = !seen_other_tags;
952 seen_rust_tags = true;
955 data.test_harness = true;
956 seen_rust_tags = !seen_other_tags || seen_rust_tags;
959 data.compile_fail = true;
960 seen_rust_tags = !seen_other_tags || seen_rust_tags;
963 x if x.starts_with("edition") => {
964 data.edition = x[7..].parse::<Edition>().ok();
966 x if allow_error_code_check && x.starts_with('E') && x.len() == 5 => {
967 if x[1..].parse::<u32>().is_ok() {
968 data.error_codes.push(x.to_owned());
969 seen_rust_tags = !seen_other_tags || seen_rust_tags;
971 seen_other_tags = true;
974 x if extra.is_some() => {
975 let s = x.to_lowercase();
976 if let Some((flag, help)) = if s == "compile-fail"
977 || s == "compile_fail"
978 || s == "compilefail"
982 "the code block will either not be tested if not marked as a rust one \
983 or won't fail if it compiles successfully",
985 } else if s == "should-panic" || s == "should_panic" || s == "shouldpanic" {
988 "the code block will either not be tested if not marked as a rust one \
989 or won't fail if it doesn't panic when running",
991 } else if s == "no-run" || s == "no_run" || s == "norun" {
994 "the code block will either not be tested if not marked as a rust one \
995 or will be run (which you might not want)",
997 } else if s == "allow-fail" || s == "allow_fail" || s == "allowfail" {
1000 "the code block will either not be tested if not marked as a rust one \
1001 or will be run (which you might not want)",
1003 } else if s == "test-harness" || s == "test_harness" || s == "testharness" {
1006 "the code block will either not be tested if not marked as a rust one \
1007 or the code will be wrapped inside a main function",
1012 if let Some(extra) = extra {
1013 extra.error_invalid_codeblock_attr(
1014 &format!("unknown attribute `{}`. Did you mean `{}`?", x, flag),
1019 seen_other_tags = true;
1021 _ => seen_other_tags = true,
1025 // ignore-foo overrides ignore
1026 if !ignores.is_empty() {
1027 data.ignore = Ignore::Some(ignores);
1030 data.rust &= !seen_other_tags || seen_rust_tags;
1037 pub fn into_string(self) -> String {
1048 // This is actually common enough to special-case
1050 return String::new();
1052 let mut replacer = |broken_link: BrokenLink<'_>| {
1055 .find(|link| link.original_text.as_str() == &*broken_link.reference)
1056 .map(|link| (link.href.as_str().into(), link.new_text.as_str().into()))
1059 let p = Parser::new_with_broken_link_callback(md, main_body_opts(), Some(&mut replacer));
1060 let p = p.into_offset_iter();
1062 let mut s = String::with_capacity(md.len() * 3 / 2);
1064 let p = HeadingLinks::new(p, None, &mut ids, heading_offset);
1065 let p = Footnotes::new(p);
1066 let p = LinkReplacer::new(p.map(|(ev, _)| ev), links);
1067 let p = TableWrapper::new(p);
1068 let p = CodeBlocks::new(p, codes, edition, playground);
1069 html::push_html(&mut s, p);
1075 impl MarkdownWithToc<'_> {
1076 crate fn into_string(self) -> String {
1077 let MarkdownWithToc(md, mut ids, codes, edition, playground) = self;
1079 let p = Parser::new_ext(md, main_body_opts()).into_offset_iter();
1081 let mut s = String::with_capacity(md.len() * 3 / 2);
1083 let mut toc = TocBuilder::new();
1086 let p = HeadingLinks::new(p, Some(&mut toc), &mut ids, HeadingOffset::H1);
1087 let p = Footnotes::new(p);
1088 let p = TableWrapper::new(p.map(|(ev, _)| ev));
1089 let p = CodeBlocks::new(p, codes, edition, playground);
1090 html::push_html(&mut s, p);
1093 format!("<nav id=\"TOC\">{}</nav>{}", toc.into_toc().print(), s)
1097 impl MarkdownHtml<'_> {
1098 crate fn into_string(self) -> String {
1099 let MarkdownHtml(md, mut ids, codes, edition, playground) = self;
1101 // This is actually common enough to special-case
1103 return String::new();
1105 let p = Parser::new_ext(md, main_body_opts()).into_offset_iter();
1107 // Treat inline HTML as plain text.
1108 let p = p.map(|event| match event.0 {
1109 Event::Html(text) => (Event::Text(text), event.1),
1113 let mut s = String::with_capacity(md.len() * 3 / 2);
1115 let p = HeadingLinks::new(p, None, &mut ids, HeadingOffset::H1);
1116 let p = Footnotes::new(p);
1117 let p = TableWrapper::new(p.map(|(ev, _)| ev));
1118 let p = CodeBlocks::new(p, codes, edition, playground);
1119 html::push_html(&mut s, p);
1125 impl MarkdownSummaryLine<'_> {
1126 crate fn into_string(self) -> String {
1127 let MarkdownSummaryLine(md, links) = self;
1128 // This is actually common enough to special-case
1130 return String::new();
1133 let mut replacer = |broken_link: BrokenLink<'_>| {
1136 .find(|link| link.original_text.as_str() == &*broken_link.reference)
1137 .map(|link| (link.href.as_str().into(), link.new_text.as_str().into()))
1140 let p = Parser::new_with_broken_link_callback(md, summary_opts(), Some(&mut replacer));
1142 let mut s = String::new();
1144 html::push_html(&mut s, LinkReplacer::new(SummaryLine::new(p), links));
1150 /// Renders a subset of Markdown in the first paragraph of the provided Markdown.
1152 /// - *Italics*, **bold**, and `inline code` styles **are** rendered.
1153 /// - Headings and links are stripped (though the text *is* rendered).
1154 /// - HTML, code blocks, and everything else are ignored.
1156 /// Returns a tuple of the rendered HTML string and whether the output was shortened
1157 /// due to the provided `length_limit`.
1158 fn markdown_summary_with_limit(
1160 link_names: &[RenderedLink],
1161 length_limit: usize,
1162 ) -> (String, bool) {
1164 return (String::new(), false);
1167 let mut replacer = |broken_link: BrokenLink<'_>| {
1170 .find(|link| link.original_text.as_str() == &*broken_link.reference)
1171 .map(|link| (link.href.as_str().into(), link.new_text.as_str().into()))
1174 let p = Parser::new_with_broken_link_callback(md, summary_opts(), Some(&mut replacer));
1175 let mut p = LinkReplacer::new(p, link_names);
1177 let mut buf = HtmlWithLimit::new(length_limit);
1178 let mut stopped_early = false;
1179 p.try_for_each(|event| {
1181 Event::Text(text) => {
1183 text.split_inclusive(char::is_whitespace).try_for_each(|word| buf.push(word));
1185 stopped_early = true;
1189 Event::Code(code) => {
1190 buf.open_tag("code");
1191 let r = buf.push(code);
1193 stopped_early = true;
1199 Event::Start(tag) => match tag {
1200 Tag::Emphasis => buf.open_tag("em"),
1201 Tag::Strong => buf.open_tag("strong"),
1202 Tag::CodeBlock(..) => return ControlFlow::BREAK,
1205 Event::End(tag) => match tag {
1206 Tag::Emphasis | Tag::Strong => buf.close_tag(),
1207 Tag::Paragraph | Tag::Heading(..) => return ControlFlow::BREAK,
1210 Event::HardBreak | Event::SoftBreak => buf.push(" ")?,
1213 ControlFlow::CONTINUE
1216 (buf.finish(), stopped_early)
1219 /// Renders a shortened first paragraph of the given Markdown as a subset of Markdown,
1220 /// making it suitable for contexts like the search index.
1222 /// Will shorten to 59 or 60 characters, including an ellipsis (…) if it was shortened.
1224 /// See [`markdown_summary_with_limit`] for details about what is rendered and what is not.
1225 crate fn short_markdown_summary(markdown: &str, link_names: &[RenderedLink]) -> String {
1226 let (mut s, was_shortened) = markdown_summary_with_limit(markdown, link_names, 59);
1235 /// Renders the first paragraph of the provided markdown as plain text.
1236 /// Useful for alt-text.
1238 /// - Headings, links, and formatting are stripped.
1239 /// - Inline code is rendered as-is, surrounded by backticks.
1240 /// - HTML and code blocks are ignored.
1241 crate fn plain_text_summary(md: &str) -> String {
1243 return String::new();
1246 let mut s = String::with_capacity(md.len() * 3 / 2);
1248 for event in Parser::new_ext(md, summary_opts()) {
1250 Event::Text(text) => s.push_str(text),
1251 Event::Code(code) => {
1256 Event::HardBreak | Event::SoftBreak => s.push(' '),
1257 Event::Start(Tag::CodeBlock(..)) => break,
1258 Event::End(Tag::Paragraph) => break,
1259 Event::End(Tag::Heading(..)) => break,
1268 crate struct MarkdownLink {
1271 pub range: Range<usize>,
1274 crate fn markdown_links(md: &str) -> Vec<MarkdownLink> {
1279 let links = RefCell::new(vec![]);
1281 // FIXME: remove this function once pulldown_cmark can provide spans for link definitions.
1282 let locate = |s: &str, fallback: Range<usize>| unsafe {
1283 let s_start = s.as_ptr();
1284 let s_end = s_start.add(s.len());
1285 let md_start = md.as_ptr();
1286 let md_end = md_start.add(md.len());
1287 if md_start <= s_start && s_end <= md_end {
1288 let start = s_start.offset_from(md_start) as usize;
1289 let end = s_end.offset_from(md_start) as usize;
1296 let span_for_link = |link: &CowStr<'_>, span: Range<usize>| {
1297 // For diagnostics, we want to underline the link's definition but `span` will point at
1298 // where the link is used. This is a problem for reference-style links, where the definition
1299 // is separate from the usage.
1301 // `Borrowed` variant means the string (the link's destination) may come directly from
1302 // the markdown text and we can locate the original link destination.
1303 // NOTE: LinkReplacer also provides `Borrowed` but possibly from other sources,
1304 // so `locate()` can fall back to use `span`.
1305 CowStr::Borrowed(s) => locate(s, span),
1307 // For anything else, we can only use the provided range.
1308 CowStr::Boxed(_) | CowStr::Inlined(_) => span,
1312 let mut push = |link: BrokenLink<'_>| {
1313 let span = span_for_link(&link.reference, link.span);
1314 links.borrow_mut().push(MarkdownLink {
1315 kind: LinkType::ShortcutUnknown,
1316 link: link.reference.to_string(),
1321 let p = Parser::new_with_broken_link_callback(md, main_body_opts(), Some(&mut push))
1322 .into_offset_iter();
1324 // There's no need to thread an IdMap through to here because
1325 // the IDs generated aren't going to be emitted anywhere.
1326 let mut ids = IdMap::new();
1327 let iter = Footnotes::new(HeadingLinks::new(p, None, &mut ids, HeadingOffset::H1));
1330 if let Event::Start(Tag::Link(kind, dest, _)) = ev.0 {
1331 debug!("found link: {}", dest);
1332 let span = span_for_link(&dest, ev.1);
1333 links.borrow_mut().push(MarkdownLink { kind, link: dest.into_string(), range: span });
1341 crate struct RustCodeBlock {
1342 /// The range in the markdown that the code block occupies. Note that this includes the fences
1343 /// for fenced code blocks.
1344 crate range: Range<usize>,
1345 /// The range in the markdown that the code within the code block occupies.
1346 crate code: Range<usize>,
1347 crate is_fenced: bool,
1348 crate lang_string: LangString,
1351 /// Returns a range of bytes for each code block in the markdown that is tagged as `rust` or
1352 /// untagged (and assumed to be rust).
1353 crate fn rust_code_blocks(md: &str, extra_info: &ExtraInfo<'_>) -> Vec<RustCodeBlock> {
1354 let mut code_blocks = vec![];
1360 let mut p = Parser::new_ext(md, main_body_opts()).into_offset_iter();
1362 while let Some((event, offset)) = p.next() {
1363 if let Event::Start(Tag::CodeBlock(syntax)) = event {
1364 let (lang_string, code_start, code_end, range, is_fenced) = match syntax {
1365 CodeBlockKind::Fenced(syntax) => {
1366 let syntax = syntax.as_ref();
1367 let lang_string = if syntax.is_empty() {
1370 LangString::parse(&*syntax, ErrorCodes::Yes, false, Some(extra_info))
1372 if !lang_string.rust {
1375 let (code_start, mut code_end) = match p.next() {
1376 Some((Event::Text(_), offset)) => (offset.start, offset.end),
1377 Some((_, sub_offset)) => {
1378 let code = Range { start: sub_offset.start, end: sub_offset.start };
1379 code_blocks.push(RustCodeBlock {
1388 let code = Range { start: offset.end, end: offset.end };
1389 code_blocks.push(RustCodeBlock {
1398 while let Some((Event::Text(_), offset)) = p.next() {
1399 code_end = offset.end;
1401 (lang_string, code_start, code_end, offset, true)
1403 CodeBlockKind::Indented => {
1404 // The ending of the offset goes too far sometime so we reduce it by one in
1406 if offset.end > offset.start && md.get(offset.end..=offset.end) == Some("\n") {
1408 LangString::default(),
1411 Range { start: offset.start, end: offset.end - 1 },
1415 (LangString::default(), offset.start, offset.end, offset, false)
1420 code_blocks.push(RustCodeBlock {
1423 code: Range { start: code_start, end: code_end },
1432 #[derive(Clone, Default, Debug)]
1434 map: FxHashMap<String, usize>,
1437 fn init_id_map() -> FxHashMap<String, usize> {
1438 let mut map = FxHashMap::default();
1439 // This is the list of IDs used in Javascript.
1440 map.insert("help".to_owned(), 1);
1441 // This is the list of IDs used in HTML generated in Rust (including the ones
1442 // used in tera template files).
1443 map.insert("mainThemeStyle".to_owned(), 1);
1444 map.insert("themeStyle".to_owned(), 1);
1445 map.insert("theme-picker".to_owned(), 1);
1446 map.insert("theme-choices".to_owned(), 1);
1447 map.insert("settings-menu".to_owned(), 1);
1448 map.insert("help-button".to_owned(), 1);
1449 map.insert("main-content".to_owned(), 1);
1450 map.insert("search".to_owned(), 1);
1451 map.insert("crate-search".to_owned(), 1);
1452 map.insert("render-detail".to_owned(), 1);
1453 map.insert("toggle-all-docs".to_owned(), 1);
1454 map.insert("all-types".to_owned(), 1);
1455 map.insert("default-settings".to_owned(), 1);
1456 map.insert("rustdoc-vars".to_owned(), 1);
1457 map.insert("sidebar-vars".to_owned(), 1);
1458 map.insert("copy-path".to_owned(), 1);
1459 map.insert("TOC".to_owned(), 1);
1460 // This is the list of IDs used by rustdoc sections (but still generated by
1462 map.insert("fields".to_owned(), 1);
1463 map.insert("variants".to_owned(), 1);
1464 map.insert("implementors-list".to_owned(), 1);
1465 map.insert("synthetic-implementors-list".to_owned(), 1);
1466 map.insert("foreign-impls".to_owned(), 1);
1467 map.insert("implementations".to_owned(), 1);
1468 map.insert("trait-implementations".to_owned(), 1);
1469 map.insert("synthetic-implementations".to_owned(), 1);
1470 map.insert("blanket-implementations".to_owned(), 1);
1471 map.insert("associated-types".to_owned(), 1);
1472 map.insert("associated-const".to_owned(), 1);
1473 map.insert("required-methods".to_owned(), 1);
1474 map.insert("provided-methods".to_owned(), 1);
1475 map.insert("implementors".to_owned(), 1);
1476 map.insert("synthetic-implementors".to_owned(), 1);
1477 map.insert("trait-implementations-list".to_owned(), 1);
1478 map.insert("synthetic-implementations-list".to_owned(), 1);
1479 map.insert("blanket-implementations-list".to_owned(), 1);
1480 map.insert("deref-methods".to_owned(), 1);
1485 pub fn new() -> Self {
1486 IdMap { map: init_id_map() }
1489 crate fn derive<S: AsRef<str> + ToString>(&mut self, candidate: S) -> String {
1490 let id = match self.map.get_mut(candidate.as_ref()) {
1491 None => candidate.to_string(),
1493 let id = format!("{}-{}", candidate.as_ref(), *a);
1499 self.map.insert(id.clone(), 1);