1 //! Script to check the validity of `href` links in our HTML documentation.
3 //! In the past we've been quite error prone to writing in broken links as most
4 //! of them are manually rather than automatically added. As files move over
5 //! time or apis change old links become stale or broken. The purpose of this
6 //! script is to check all relative links in our documentation to make sure they
7 //! actually point to a valid place.
9 //! Currently this doesn't actually do any HTML parsing or anything fancy like
10 //! that, it just has a simple "regex" to search for `href` and `id` tags.
11 //! These values are then translated to file URLs if possible and then the
12 //! destination is asserted to exist.
14 //! A few exceptions are allowed as there's known bugs in rustdoc, but this
15 //! should catch the majority of "broken link" cases.
17 #![feature(str_split_once)]
19 use std::collections::hash_map::Entry;
20 use std::collections::{HashMap, HashSet};
23 use std::path::{Component, Path, PathBuf};
26 use once_cell::sync::Lazy;
29 use crate::Redirect::*;
31 // Add linkcheck exceptions here
32 // If at all possible you should use intra-doc links to avoid linkcheck issues. These
33 // are cases where that does not work
34 // [(generated_documentation_page, &[broken_links])]
35 const LINKCHECK_EXCEPTIONS: &[(&str, &[&str])] = &[
36 // These are methods on slice, and `Self` does not work on primitive impls
37 // in intra-doc links (primitive impls are weird)
38 // https://github.com/rust-lang/rust/issues/62834 is necessary to be
39 // able to link to slices
40 ("std/io/struct.IoSlice.html", &["#method.as_mut_ptr", "#method.sort_by_key"]),
41 // These try to link to std::collections, but are defined in alloc
42 // https://github.com/rust-lang/rust/issues/74481
43 ("std/collections/btree_map/struct.BTreeMap.html", &["#insert-and-complex-keys"]),
44 ("std/collections/btree_set/struct.BTreeSet.html", &["#insert-and-complex-keys"]),
45 ("alloc/collections/btree_map/struct.BTreeMap.html", &["#insert-and-complex-keys"]),
46 ("alloc/collections/btree_set/struct.BTreeSet.html", &["#insert-and-complex-keys"]),
50 const INTRA_DOC_LINK_EXCEPTIONS: &[(&str, &[&str])] = &[
51 // This will never have links that are not in other pages.
52 // To avoid repeating the exceptions twice, an empty list means all broken links are allowed.
53 ("reference/print.html", &[]),
54 // All the reference 'links' are actually ENBF highlighted as code
55 ("reference/comments.html", &[
59 ("reference/identifiers.html", &[
60 "a</code>-<code>z</code> <code>A</code>-<code>Z",
61 "a</code>-<code>z</code> <code>A</code>-<code>Z</code> <code>0</code>-<code>9</code> <code>_",
62 "a</code>-<code>z</code> <code>A</code>-<code>Z</code>] [<code>a</code>-<code>z</code> <code>A</code>-<code>Z</code> <code>0</code>-<code>9</code> <code>_",
64 ("reference/tokens.html", &[
69 "0</code>-<code>9</code> <code>a</code>-<code>f</code> <code>A</code>-<code>F",
71 ("reference/notation.html", &[
75 // This is being used in the sense of 'inclusive range', not a markdown link
76 ("core/ops/struct.RangeInclusive.html", &["begin</code>, <code>end"]),
77 ("std/ops/struct.RangeInclusive.html", &["begin</code>, <code>end"]),
78 ("core/slice/trait.SliceIndex.html", &["begin</code>, <code>end"]),
79 ("alloc/slice/trait.SliceIndex.html", &["begin</code>, <code>end"]),
80 ("std/slice/trait.SliceIndex.html", &["begin</code>, <code>end"]),
84 static BROKEN_INTRA_DOC_LINK: Lazy<Regex> =
85 Lazy::new(|| Regex::new(r#"\[<code>(.*)</code>\]"#).unwrap());
91 Err(e) => panic!("{} failed with {:?}", stringify!($e), e),
97 let docs = env::args_os().nth(1).unwrap();
98 let docs = env::current_dir().unwrap().join(docs);
99 let mut errors = false;
100 walk(&mut HashMap::new(), &docs, &docs, &mut errors);
102 panic!("found some broken links");
108 IOError(std::io::Error),
109 BrokenRedirect(PathBuf, std::io::Error),
120 ids: HashSet<String>,
123 type Cache = HashMap<PathBuf, FileEntry>;
125 fn small_url_encode(s: &str) -> String {
126 s.replace("<", "%3C")
137 .replace("\"", "%22")
141 fn parse_ids(&mut self, file: &Path, contents: &str, errors: &mut bool) {
142 if self.ids.is_empty() {
143 with_attrs_in_source(contents, " id", |fragment, i, _| {
144 let frag = fragment.trim_start_matches("#").to_owned();
145 let encoded = small_url_encode(&frag);
146 if !self.ids.insert(frag) {
148 println!("{}:{}: id is not unique: `{}`", file.display(), i, fragment);
150 // Just in case, we also add the encoded id.
151 self.ids.insert(encoded);
157 fn walk(cache: &mut Cache, root: &Path, dir: &Path, errors: &mut bool) {
158 for entry in t!(dir.read_dir()).map(|e| t!(e)) {
159 let path = entry.path();
160 let kind = t!(entry.file_type());
162 walk(cache, root, &path, errors);
164 let pretty_path = check(cache, root, &path, errors);
165 if let Some(pretty_path) = pretty_path {
166 let entry = cache.get_mut(&pretty_path).unwrap();
167 // we don't need the source anymore,
168 // so drop to reduce memory-usage
169 entry.source = Rc::new(String::new());
175 fn is_intra_doc_exception(file: &Path, link: &str) -> bool {
176 if let Some(entry) = INTRA_DOC_LINK_EXCEPTIONS.iter().find(|&(f, _)| file.ends_with(f)) {
177 entry.1.is_empty() || entry.1.contains(&link)
183 fn is_exception(file: &Path, link: &str) -> bool {
184 if let Some(entry) = LINKCHECK_EXCEPTIONS.iter().find(|&(f, _)| file.ends_with(f)) {
185 entry.1.contains(&link)
187 // FIXME(#63351): Concat trait in alloc/slice reexported in primitive page
189 // NOTE: This cannot be added to `LINKCHECK_EXCEPTIONS` because the resolved path
190 // calculated in `check` function is outside `build/<triple>/doc` dir.
191 // So the `strip_prefix` method just returns the old absolute broken path.
192 if file.ends_with("std/primitive.slice.html") {
193 if link.ends_with("primitive.slice.html") {
201 fn check(cache: &mut Cache, root: &Path, file: &Path, errors: &mut bool) -> Option<PathBuf> {
202 // Ignore non-HTML files.
203 if file.extension().and_then(|s| s.to_str()) != Some("html") {
207 let res = load_file(cache, root, file, SkipRedirect);
208 let (pretty_file, contents) = match res {
210 Err(_) => return None,
213 cache.get_mut(&pretty_file).unwrap().parse_ids(&pretty_file, &contents, errors);
216 // Search for anything that's the regex 'href[ ]*=[ ]*".*?"'
217 with_attrs_in_source(&contents, " href", |url, i, base| {
218 // Ignore external URLs
219 if url.starts_with("http:")
220 || url.starts_with("https:")
221 || url.starts_with("javascript:")
222 || url.starts_with("ftp:")
223 || url.starts_with("irc:")
224 || url.starts_with("data:")
228 let (url, fragment) = match url.split_once('#') {
230 Some((url, fragment)) => (url, Some(fragment)),
232 // NB: the `splitn` always succeeds, even if the delimiter is not present.
233 let url = url.splitn(2, '?').next().unwrap();
235 // Once we've plucked out the URL, parse it using our base url and
236 // then try to extract a file path.
237 let mut path = file.to_path_buf();
238 if !base.is_empty() || !url.is_empty() {
240 for part in Path::new(base).join(url).components() {
242 Component::Prefix(_) | Component::RootDir => {
243 // Avoid absolute paths as they make the docs not
244 // relocatable by making assumptions on where the docs
245 // are hosted relative to the site root.
248 "{}:{}: absolute path - {}",
249 pretty_file.display(),
251 Path::new(base).join(url).display()
255 Component::CurDir => {}
256 Component::ParentDir => {
259 Component::Normal(s) => {
266 // Alright, if we've found a file name then this file had better
267 // exist! If it doesn't then we register and print an error.
270 // Links to directories show as directory listings when viewing
271 // the docs offline so it's best to avoid them.
273 let pretty_path = path.strip_prefix(root).unwrap_or(&path);
275 "{}:{}: directory link - {}",
276 pretty_file.display(),
278 pretty_path.display()
282 if let Some(extension) = path.extension() {
283 // Ignore none HTML files.
284 if extension != "html" {
288 let res = load_file(cache, root, &path, FromRedirect(false));
289 let (pretty_path, contents) = match res {
291 Err(LoadError::IOError(err)) => {
292 panic!("error loading {}: {}", path.display(), err);
294 Err(LoadError::BrokenRedirect(target, _)) => {
297 "{}:{}: broken redirect to {}",
298 pretty_file.display(),
304 Err(LoadError::IsRedirect) => unreachable!(),
307 if let Some(ref fragment) = fragment {
308 // Fragments like `#1-6` are most likely line numbers to be
309 // interpreted by javascript, so we're ignoring these
310 if fragment.splitn(2, '-').all(|f| f.chars().all(|c| c.is_numeric())) {
314 // These appear to be broken in mdbook right now?
315 if fragment.starts_with('-') {
319 let entry = &mut cache.get_mut(&pretty_path).unwrap();
320 entry.parse_ids(&pretty_path, &contents, errors);
322 if !entry.ids.contains(*fragment) && !is_exception(file, &format!("#{}", fragment))
325 print!("{}:{}: broken link fragment ", pretty_file.display(), i + 1);
326 println!("`#{}` pointing to `{}`", fragment, pretty_path.display());
330 let pretty_path = path.strip_prefix(root).unwrap_or(&path);
331 if !is_exception(file, pretty_path.to_str().unwrap()) {
333 print!("{}:{}: broken link - ", pretty_file.display(), i + 1);
334 println!("{}", pretty_path.display());
339 // Search for intra-doc links that rustdoc didn't warn about
340 // FIXME(#77199, 77200) Rustdoc should just warn about these directly.
341 // NOTE: only looks at one line at a time; in practice this should find most links
342 for (i, line) in contents.lines().enumerate() {
343 for broken_link in BROKEN_INTRA_DOC_LINK.captures_iter(line) {
344 if !is_intra_doc_exception(file, &broken_link[1]) {
346 print!("{}:{}: broken intra-doc link - ", pretty_file.display(), i + 1);
347 println!("{}", &broken_link[0]);
359 ) -> Result<(PathBuf, Rc<String>), LoadError> {
360 let pretty_file = PathBuf::from(file.strip_prefix(root).unwrap_or(&file));
362 let (maybe_redirect, contents) = match cache.entry(pretty_file.clone()) {
363 Entry::Occupied(entry) => (None, entry.get().source.clone()),
364 Entry::Vacant(entry) => {
365 let contents = match fs::read_to_string(file) {
368 return Err(if let FromRedirect(true) = redirect {
369 LoadError::BrokenRedirect(file.to_path_buf(), err)
371 LoadError::IOError(err)
376 let maybe = maybe_redirect(&contents);
378 if let SkipRedirect = redirect {
379 return Err(LoadError::IsRedirect);
382 entry.insert(FileEntry { source: contents.clone(), ids: HashSet::new() });
387 match maybe_redirect.map(|url| file.parent().unwrap().join(url)) {
388 Some(redirect_file) => load_file(cache, root, &redirect_file, FromRedirect(true)),
389 None => Ok((pretty_file, contents)),
393 fn maybe_redirect(source: &str) -> Option<String> {
394 const REDIRECT: &str = "<p>Redirecting to <a href=";
396 let mut lines = source.lines();
397 let redirect_line = lines.nth(6)?;
399 redirect_line.find(REDIRECT).map(|i| {
400 let rest = &redirect_line[(i + REDIRECT.len() + 1)..];
401 let pos_quote = rest.find('"').unwrap();
402 rest[..pos_quote].to_owned()
406 fn with_attrs_in_source<F: FnMut(&str, usize, &str)>(contents: &str, attr: &str, mut f: F) {
408 for (i, mut line) in contents.lines().enumerate() {
409 while let Some(j) = line.find(attr) {
410 let rest = &line[j + attr.len()..];
411 // The base tag should always be the first link in the document so
412 // we can get away with using one pass.
413 let is_base = line[..j].ends_with("<base");
415 let pos_equals = match rest.find('=') {
419 if rest[..pos_equals].trim_start_matches(' ') != "" {
423 let rest = &rest[pos_equals + 1..];
425 let pos_quote = match rest.find(&['"', '\''][..]) {
429 let quote_delim = rest.as_bytes()[pos_quote] as char;
431 if rest[..pos_quote].trim_start_matches(' ') != "" {
434 let rest = &rest[pos_quote + 1..];
435 let url = match rest.find(quote_delim) {
436 Some(i) => &rest[..i],