From 4547b622d8d29df964fa2914213088b148c498fc Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Wed, 17 Apr 2024 14:18:32 +0200
Subject: Merging upstream version 1.67.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 src/librustdoc/passes/bare_urls.rs                 | 110 ------
 src/librustdoc/passes/calculate_doc_coverage.rs    |   4 +-
 src/librustdoc/passes/check_code_block_syntax.rs   | 209 ----------
 src/librustdoc/passes/check_doc_test_visibility.rs |   4 +-
 src/librustdoc/passes/collect_intra_doc_links.rs   |   5 +-
 src/librustdoc/passes/collect_trait_impls.rs       |   6 +-
 src/librustdoc/passes/html_tags.rs                 | 430 ---------------------
 src/librustdoc/passes/lint.rs                      |  33 ++
 src/librustdoc/passes/lint/bare_urls.rs            |  89 +++++
 .../passes/lint/check_code_block_syntax.rs         | 170 ++++++++
 src/librustdoc/passes/lint/html_tags.rs            | 407 +++++++++++++++++++
 src/librustdoc/passes/mod.rs                       |  18 +-
 src/librustdoc/passes/strip_hidden.rs              |   1 +
 src/librustdoc/passes/strip_priv_imports.rs        |   4 +-
 src/librustdoc/passes/strip_private.rs             |   4 +-
 src/librustdoc/passes/stripper.rs                  |  49 ++-
 16 files changed, 751 insertions(+), 792 deletions(-)
 delete mode 100644 src/librustdoc/passes/bare_urls.rs
 delete mode 100644 src/librustdoc/passes/check_code_block_syntax.rs
 delete mode 100644 src/librustdoc/passes/html_tags.rs
 create mode 100644 src/librustdoc/passes/lint.rs
 create mode 100644 src/librustdoc/passes/lint/bare_urls.rs
 create mode 100644 src/librustdoc/passes/lint/check_code_block_syntax.rs
 create mode 100644 src/librustdoc/passes/lint/html_tags.rs

(limited to 'src/librustdoc/passes')

diff --git a/src/librustdoc/passes/bare_urls.rs b/src/librustdoc/passes/bare_urls.rs
deleted file mode 100644
index 7ff3ccef9..000000000
--- a/src/librustdoc/passes/bare_urls.rs
+++ /dev/null
@@ -1,110 +0,0 @@
-//! Detects links that are not linkified, e.g., in Markdown such as `Go to https://example.com/.`
-//! Suggests wrapping the link with angle brackets: `Go to <https://example.com/>.` to linkify it.
-use super::Pass;
-use crate::clean::*;
-use crate::core::DocContext;
-use crate::html::markdown::main_body_opts;
-use crate::visit::DocVisitor;
-use core::ops::Range;
-use pulldown_cmark::{Event, Parser, Tag};
-use regex::Regex;
-use rustc_errors::Applicability;
-use std::mem;
-use std::sync::LazyLock;
-
-pub(crate) const CHECK_BARE_URLS: Pass = Pass {
-    name: "check-bare-urls",
-    run: check_bare_urls,
-    description: "detects URLs that are not hyperlinks",
-};
-
-static URL_REGEX: LazyLock<Regex> = LazyLock::new(|| {
-    Regex::new(concat!(
-        r"https?://",                          // url scheme
-        r"([-a-zA-Z0-9@:%._\+~#=]{2,256}\.)+", // one or more subdomains
-        r"[a-zA-Z]{2,63}",                     // root domain
-        r"\b([-a-zA-Z0-9@:%_\+.~#?&/=]*)"      // optional query or url fragments
-    ))
-    .expect("failed to build regex")
-});
-
-struct BareUrlsLinter<'a, 'tcx> {
-    cx: &'a mut DocContext<'tcx>,
-}
-
-impl<'a, 'tcx> BareUrlsLinter<'a, 'tcx> {
-    fn find_raw_urls(
-        &self,
-        text: &str,
-        range: Range<usize>,
-        f: &impl Fn(&DocContext<'_>, &str, &str, Range<usize>),
-    ) {
-        trace!("looking for raw urls in {}", text);
-        // For now, we only check "full" URLs (meaning, starting with "http://" or "https://").
-        for match_ in URL_REGEX.find_iter(text) {
-            let url = match_.as_str();
-            let url_range = match_.range();
-            f(
-                self.cx,
-                "this URL is not a hyperlink",
-                url,
-                Range { start: range.start + url_range.start, end: range.start + url_range.end },
-            );
-        }
-    }
-}
-
-pub(crate) fn check_bare_urls(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
-    BareUrlsLinter { cx }.visit_crate(&krate);
-    krate
-}
-
-impl<'a, 'tcx> DocVisitor for BareUrlsLinter<'a, 'tcx> {
-    fn visit_item(&mut self, item: &Item) {
-        let Some(hir_id) = DocContext::as_local_hir_id(self.cx.tcx, item.item_id)
-        else {
-            // If non-local, no need to check anything.
-            return;
-        };
-        let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
-        if !dox.is_empty() {
-            let report_diag = |cx: &DocContext<'_>, msg: &str, url: &str, range: Range<usize>| {
-                let sp = super::source_span_for_markdown_range(cx.tcx, &dox, &range, &item.attrs)
-                    .unwrap_or_else(|| item.attr_span(cx.tcx));
-                cx.tcx.struct_span_lint_hir(crate::lint::BARE_URLS, hir_id, sp, msg, |lint| {
-                    lint.note("bare URLs are not automatically turned into clickable links")
-                        .span_suggestion(
-                            sp,
-                            "use an automatic link instead",
-                            format!("<{}>", url),
-                            Applicability::MachineApplicable,
-                        )
-                });
-            };
-
-            let mut p = Parser::new_ext(&dox, main_body_opts()).into_offset_iter();
-
-            while let Some((event, range)) = p.next() {
-                match event {
-                    Event::Text(s) => self.find_raw_urls(&s, range, &report_diag),
-                    // We don't want to check the text inside code blocks or links.
-                    Event::Start(tag @ (Tag::CodeBlock(_) | Tag::Link(..))) => {
-                        while let Some((event, _)) = p.next() {
-                            match event {
-                                Event::End(end)
-                                    if mem::discriminant(&end) == mem::discriminant(&tag) =>
-                                {
-                                    break;
-                                }
-                                _ => {}
-                            }
-                        }
-                    }
-                    _ => {}
-                }
-            }
-        }
-
-        self.visit_item_recur(item)
-    }
-}
diff --git a/src/librustdoc/passes/calculate_doc_coverage.rs b/src/librustdoc/passes/calculate_doc_coverage.rs
index 48835abf9..02b227896 100644
--- a/src/librustdoc/passes/calculate_doc_coverage.rs
+++ b/src/librustdoc/passes/calculate_doc_coverage.rs
@@ -244,10 +244,10 @@ impl<'a, 'b> DocVisitor for CoverageCalculator<'a, 'b> {
                         matches!(
                             node,
                             hir::Node::Variant(hir::Variant {
-                                data: hir::VariantData::Tuple(_, _),
+                                data: hir::VariantData::Tuple(_, _, _),
                                 ..
                             }) | hir::Node::Item(hir::Item {
-                                kind: hir::ItemKind::Struct(hir::VariantData::Tuple(_, _), _),
+                                kind: hir::ItemKind::Struct(hir::VariantData::Tuple(_, _, _), _),
                                 ..
                             })
                         )
diff --git a/src/librustdoc/passes/check_code_block_syntax.rs b/src/librustdoc/passes/check_code_block_syntax.rs
deleted file mode 100644
index 2e651b538..000000000
--- a/src/librustdoc/passes/check_code_block_syntax.rs
+++ /dev/null
@@ -1,209 +0,0 @@
-//! Validates syntax inside Rust code blocks (\`\`\`rust).
-use rustc_data_structures::sync::{Lock, Lrc};
-use rustc_errors::{
-    emitter::Emitter,
-    translation::{to_fluent_args, Translate},
-    Applicability, Diagnostic, Handler, LazyFallbackBundle,
-};
-use rustc_parse::parse_stream_from_source_str;
-use rustc_session::parse::ParseSess;
-use rustc_span::hygiene::{AstPass, ExpnData, ExpnKind, LocalExpnId};
-use rustc_span::source_map::{FilePathMapping, SourceMap};
-use rustc_span::{FileName, InnerSpan, DUMMY_SP};
-
-use crate::clean;
-use crate::core::DocContext;
-use crate::html::markdown::{self, RustCodeBlock};
-use crate::passes::Pass;
-use crate::visit::DocVisitor;
-
-pub(crate) const CHECK_CODE_BLOCK_SYNTAX: Pass = Pass {
-    name: "check-code-block-syntax",
-    run: check_code_block_syntax,
-    description: "validates syntax inside Rust code blocks",
-};
-
-pub(crate) fn check_code_block_syntax(
-    krate: clean::Crate,
-    cx: &mut DocContext<'_>,
-) -> clean::Crate {
-    SyntaxChecker { cx }.visit_crate(&krate);
-    krate
-}
-
-struct SyntaxChecker<'a, 'tcx> {
-    cx: &'a DocContext<'tcx>,
-}
-
-impl<'a, 'tcx> SyntaxChecker<'a, 'tcx> {
-    fn check_rust_syntax(&self, item: &clean::Item, dox: &str, code_block: RustCodeBlock) {
-        let buffer = Lrc::new(Lock::new(Buffer::default()));
-        let fallback_bundle =
-            rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
-        let emitter = BufferEmitter { buffer: Lrc::clone(&buffer), fallback_bundle };
-
-        let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
-        let handler = Handler::with_emitter(false, None, Box::new(emitter));
-        let source = dox[code_block.code].to_owned();
-        let sess = ParseSess::with_span_handler(handler, sm);
-
-        let edition = code_block.lang_string.edition.unwrap_or_else(|| self.cx.tcx.sess.edition());
-        let expn_data = ExpnData::default(
-            ExpnKind::AstPass(AstPass::TestHarness),
-            DUMMY_SP,
-            edition,
-            None,
-            None,
-        );
-        let expn_id =
-            self.cx.tcx.with_stable_hashing_context(|hcx| LocalExpnId::fresh(expn_data, hcx));
-        let span = DUMMY_SP.fresh_expansion(expn_id);
-
-        let is_empty = rustc_driver::catch_fatal_errors(|| {
-            parse_stream_from_source_str(
-                FileName::Custom(String::from("doctest")),
-                source,
-                &sess,
-                Some(span),
-            )
-            .is_empty()
-        })
-        .unwrap_or(false);
-        let buffer = buffer.borrow();
-
-        if !buffer.has_errors && !is_empty {
-            // No errors in a non-empty program.
-            return;
-        }
-
-        let Some(local_id) = item.item_id.as_def_id().and_then(|x| x.as_local())
-        else {
-            // We don't need to check the syntax for other crates so returning
-            // without doing anything should not be a problem.
-            return;
-        };
-
-        let hir_id = self.cx.tcx.hir().local_def_id_to_hir_id(local_id);
-        let empty_block = code_block.lang_string == Default::default() && code_block.is_fenced;
-        let is_ignore = code_block.lang_string.ignore != markdown::Ignore::None;
-
-        // The span and whether it is precise or not.
-        let (sp, precise_span) = match super::source_span_for_markdown_range(
-            self.cx.tcx,
-            dox,
-            &code_block.range,
-            &item.attrs,
-        ) {
-            Some(sp) => (sp, true),
-            None => (item.attr_span(self.cx.tcx), false),
-        };
-
-        let msg = if buffer.has_errors {
-            "could not parse code block as Rust code"
-        } else {
-            "Rust code block is empty"
-        };
-
-        // Finally build and emit the completed diagnostic.
-        // All points of divergence have been handled earlier so this can be
-        // done the same way whether the span is precise or not.
-        self.cx.tcx.struct_span_lint_hir(
-            crate::lint::INVALID_RUST_CODEBLOCKS,
-            hir_id,
-            sp,
-            msg,
-            |lint| {
-                let explanation = if is_ignore {
-                    "`ignore` code blocks require valid Rust code for syntax highlighting; \
-                    mark blocks that do not contain Rust code as text"
-                } else {
-                    "mark blocks that do not contain Rust code as text"
-                };
-
-                if precise_span {
-                    if is_ignore {
-                        // giving an accurate suggestion is hard because `ignore` might not have come first in the list.
-                        // just give a `help` instead.
-                        lint.span_help(
-                            sp.from_inner(InnerSpan::new(0, 3)),
-                            &format!("{}: ```text", explanation),
-                        );
-                    } else if empty_block {
-                        lint.span_suggestion(
-                            sp.from_inner(InnerSpan::new(0, 3)).shrink_to_hi(),
-                            explanation,
-                            "text",
-                            Applicability::MachineApplicable,
-                        );
-                    }
-                } else if empty_block || is_ignore {
-                    lint.help(&format!("{}: ```text", explanation));
-                }
-
-                // FIXME(#67563): Provide more context for these errors by displaying the spans inline.
-                for message in buffer.messages.iter() {
-                    lint.note(message);
-                }
-
-                lint
-            },
-        );
-    }
-}
-
-impl<'a, 'tcx> DocVisitor for SyntaxChecker<'a, 'tcx> {
-    fn visit_item(&mut self, item: &clean::Item) {
-        if let Some(dox) = &item.attrs.collapsed_doc_value() {
-            let sp = item.attr_span(self.cx.tcx);
-            let extra = crate::html::markdown::ExtraInfo::new_did(
-                self.cx.tcx,
-                item.item_id.expect_def_id(),
-                sp,
-            );
-            for code_block in markdown::rust_code_blocks(dox, &extra) {
-                self.check_rust_syntax(item, dox, code_block);
-            }
-        }
-
-        self.visit_item_recur(item)
-    }
-}
-
-#[derive(Default)]
-struct Buffer {
-    messages: Vec<String>,
-    has_errors: bool,
-}
-
-struct BufferEmitter {
-    buffer: Lrc<Lock<Buffer>>,
-    fallback_bundle: LazyFallbackBundle,
-}
-
-impl Translate for BufferEmitter {
-    fn fluent_bundle(&self) -> Option<&Lrc<rustc_errors::FluentBundle>> {
-        None
-    }
-
-    fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
-        &**self.fallback_bundle
-    }
-}
-
-impl Emitter for BufferEmitter {
-    fn emit_diagnostic(&mut self, diag: &Diagnostic) {
-        let mut buffer = self.buffer.borrow_mut();
-
-        let fluent_args = to_fluent_args(diag.args());
-        let translated_main_message = self.translate_message(&diag.message[0].0, &fluent_args);
-
-        buffer.messages.push(format!("error from rustc: {}", translated_main_message));
-        if diag.is_error() {
-            buffer.has_errors = true;
-        }
-    }
-
-    fn source_map(&self) -> Option<&Lrc<SourceMap>> {
-        None
-    }
-}
diff --git a/src/librustdoc/passes/check_doc_test_visibility.rs b/src/librustdoc/passes/check_doc_test_visibility.rs
index 7740c6d5b..057d2fdd9 100644
--- a/src/librustdoc/passes/check_doc_test_visibility.rs
+++ b/src/librustdoc/passes/check_doc_test_visibility.rs
@@ -56,7 +56,7 @@ impl crate::doctest::Tester for Tests {
 }
 
 pub(crate) fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> bool {
-    if !cx.cache.effective_visibilities.is_directly_public(item.item_id.expect_def_id())
+    if !cx.cache.effective_visibilities.is_directly_public(cx.tcx, item.item_id.expect_def_id())
         || matches!(
             *item.kind,
             clean::StructFieldItem(_)
@@ -130,7 +130,7 @@ pub(crate) fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item
             );
         }
     } else if tests.found_tests > 0
-        && !cx.cache.effective_visibilities.is_exported(item.item_id.expect_def_id())
+        && !cx.cache.effective_visibilities.is_exported(cx.tcx, item.item_id.expect_def_id())
     {
         cx.tcx.struct_span_lint_hir(
             crate::lint::PRIVATE_DOC_TESTS,
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 8aa0abd36..37a28b6b7 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -402,6 +402,7 @@ impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
             })
             .and_then(|self_id| match tcx.def_kind(self_id) {
                 DefKind::Impl => self.def_id_to_res(self_id),
+                DefKind::Use => None,
                 def_kind => Some(Res::Def(def_kind, self_id)),
             })
     }
@@ -1772,7 +1773,6 @@ fn resolution_failure(
 
                     // Otherwise, it must be an associated item or variant
                     let res = partial_res.expect("None case was handled by `last_found_module`");
-                    let name = res.name(tcx);
                     let kind = match res {
                         Res::Def(kind, _) => Some(kind),
                         Res::Primitive(_) => None,
@@ -1814,6 +1814,7 @@ fn resolution_failure(
                     } else {
                         "associated item"
                     };
+                    let name = res.name(tcx);
                     let note = format!(
                         "the {} `{}` has no {} named `{}`",
                         res.descr(),
@@ -1893,7 +1894,7 @@ fn disambiguator_error(
     diag_info.link_range = disambiguator_range;
     report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, _sp| {
         let msg = format!(
-            "see {}/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
+            "see {}/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
             crate::DOC_RUST_LANG_ORG_CHANNEL
         );
         diag.note(&msg);
diff --git a/src/librustdoc/passes/collect_trait_impls.rs b/src/librustdoc/passes/collect_trait_impls.rs
index 6b699c790..d57f981d5 100644
--- a/src/librustdoc/passes/collect_trait_impls.rs
+++ b/src/librustdoc/passes/collect_trait_impls.rs
@@ -8,7 +8,7 @@ use crate::formats::cache::Cache;
 use crate::visit::DocVisitor;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::ty::{self, DefIdTree};
 use rustc_span::symbol::sym;
 
@@ -25,7 +25,9 @@ pub(crate) fn collect_trait_impls(mut krate: Crate, cx: &mut DocContext<'_>) ->
         synth.impls
     });
 
-    let prims: FxHashSet<PrimitiveType> = krate.primitives.iter().map(|p| p.1).collect();
+    let local_crate = ExternalCrate { crate_num: LOCAL_CRATE };
+    let prims: FxHashSet<PrimitiveType> =
+        local_crate.primitives(cx.tcx).iter().map(|p| p.1).collect();
 
     let crate_items = {
         let mut coll = ItemCollector::new();
diff --git a/src/librustdoc/passes/html_tags.rs b/src/librustdoc/passes/html_tags.rs
deleted file mode 100644
index a89ed7c7e..000000000
--- a/src/librustdoc/passes/html_tags.rs
+++ /dev/null
@@ -1,430 +0,0 @@
-//! Detects invalid HTML (like an unclosed `<span>`) in doc comments.
-use super::Pass;
-use crate::clean::*;
-use crate::core::DocContext;
-use crate::html::markdown::main_body_opts;
-use crate::visit::DocVisitor;
-
-use pulldown_cmark::{BrokenLink, Event, LinkType, Parser, Tag};
-
-use std::iter::Peekable;
-use std::ops::Range;
-use std::str::CharIndices;
-
-pub(crate) const CHECK_INVALID_HTML_TAGS: Pass = Pass {
-    name: "check-invalid-html-tags",
-    run: check_invalid_html_tags,
-    description: "detects invalid HTML tags in doc comments",
-};
-
-struct InvalidHtmlTagsLinter<'a, 'tcx> {
-    cx: &'a mut DocContext<'tcx>,
-}
-
-pub(crate) fn check_invalid_html_tags(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
-    let mut coll = InvalidHtmlTagsLinter { cx };
-    coll.visit_crate(&krate);
-    krate
-}
-
-const ALLOWED_UNCLOSED: &[&str] = &[
-    "area", "base", "br", "col", "embed", "hr", "img", "input", "keygen", "link", "meta", "param",
-    "source", "track", "wbr",
-];
-
-fn drop_tag(
-    tags: &mut Vec<(String, Range<usize>)>,
-    tag_name: String,
-    range: Range<usize>,
-    f: &impl Fn(&str, &Range<usize>, bool),
-) {
-    let tag_name_low = tag_name.to_lowercase();
-    if let Some(pos) = tags.iter().rposition(|(t, _)| t.to_lowercase() == tag_name_low) {
-        // If the tag is nested inside a "<script>" or a "<style>" tag, no warning should
-        // be emitted.
-        let should_not_warn = tags.iter().take(pos + 1).any(|(at, _)| {
-            let at = at.to_lowercase();
-            at == "script" || at == "style"
-        });
-        for (last_tag_name, last_tag_span) in tags.drain(pos + 1..) {
-            if should_not_warn {
-                continue;
-            }
-            let last_tag_name_low = last_tag_name.to_lowercase();
-            if ALLOWED_UNCLOSED.contains(&last_tag_name_low.as_str()) {
-                continue;
-            }
-            // `tags` is used as a queue, meaning that everything after `pos` is included inside it.
-            // So `<h2><h3></h2>` will look like `["h2", "h3"]`. So when closing `h2`, we will still
-            // have `h3`, meaning the tag wasn't closed as it should have.
-            f(&format!("unclosed HTML tag `{}`", last_tag_name), &last_tag_span, true);
-        }
-        // Remove the `tag_name` that was originally closed
-        tags.pop();
-    } else {
-        // It can happen for example in this case: `<h2></script></h2>` (the `h2` tag isn't required
-        // but it helps for the visualization).
-        f(&format!("unopened HTML tag `{}`", tag_name), &range, false);
-    }
-}
-
-fn extract_path_backwards(text: &str, end_pos: usize) -> Option<usize> {
-    use rustc_lexer::{is_id_continue, is_id_start};
-    let mut current_pos = end_pos;
-    loop {
-        if current_pos >= 2 && text[..current_pos].ends_with("::") {
-            current_pos -= 2;
-        }
-        let new_pos = text[..current_pos]
-            .char_indices()
-            .rev()
-            .take_while(|(_, c)| is_id_start(*c) || is_id_continue(*c))
-            .reduce(|_accum, item| item)
-            .and_then(|(new_pos, c)| is_id_start(c).then_some(new_pos));
-        if let Some(new_pos) = new_pos {
-            if current_pos != new_pos {
-                current_pos = new_pos;
-                continue;
-            }
-        }
-        break;
-    }
-    if current_pos == end_pos { None } else { Some(current_pos) }
-}
-
-fn extract_path_forward(text: &str, start_pos: usize) -> Option<usize> {
-    use rustc_lexer::{is_id_continue, is_id_start};
-    let mut current_pos = start_pos;
-    loop {
-        if current_pos < text.len() && text[current_pos..].starts_with("::") {
-            current_pos += 2;
-        } else {
-            break;
-        }
-        let mut chars = text[current_pos..].chars();
-        if let Some(c) = chars.next() {
-            if is_id_start(c) {
-                current_pos += c.len_utf8();
-            } else {
-                break;
-            }
-        }
-        while let Some(c) = chars.next() {
-            if is_id_continue(c) {
-                current_pos += c.len_utf8();
-            } else {
-                break;
-            }
-        }
-    }
-    if current_pos == start_pos { None } else { Some(current_pos) }
-}
-
-fn is_valid_for_html_tag_name(c: char, is_empty: bool) -> bool {
-    // https://spec.commonmark.org/0.30/#raw-html
-    //
-    // > A tag name consists of an ASCII letter followed by zero or more ASCII letters, digits, or
-    // > hyphens (-).
-    c.is_ascii_alphabetic() || !is_empty && (c == '-' || c.is_ascii_digit())
-}
-
-fn extract_html_tag(
-    tags: &mut Vec<(String, Range<usize>)>,
-    text: &str,
-    range: &Range<usize>,
-    start_pos: usize,
-    iter: &mut Peekable<CharIndices<'_>>,
-    f: &impl Fn(&str, &Range<usize>, bool),
-) {
-    let mut tag_name = String::new();
-    let mut is_closing = false;
-    let mut prev_pos = start_pos;
-
-    loop {
-        let (pos, c) = match iter.peek() {
-            Some((pos, c)) => (*pos, *c),
-            // In case we reached the of the doc comment, we want to check that it's an
-            // unclosed HTML tag. For example "/// <h3".
-            None => (prev_pos, '\0'),
-        };
-        prev_pos = pos;
-        // Checking if this is a closing tag (like `</a>` for `<a>`).
-        if c == '/' && tag_name.is_empty() {
-            is_closing = true;
-        } else if is_valid_for_html_tag_name(c, tag_name.is_empty()) {
-            tag_name.push(c);
-        } else {
-            if !tag_name.is_empty() {
-                let mut r = Range { start: range.start + start_pos, end: range.start + pos };
-                if c == '>' {
-                    // In case we have a tag without attribute, we can consider the span to
-                    // refer to it fully.
-                    r.end += 1;
-                }
-                if is_closing {
-                    // In case we have "</div >" or even "</div         >".
-                    if c != '>' {
-                        if !c.is_whitespace() {
-                            // It seems like it's not a valid HTML tag.
-                            break;
-                        }
-                        let mut found = false;
-                        for (new_pos, c) in text[pos..].char_indices() {
-                            if !c.is_whitespace() {
-                                if c == '>' {
-                                    r.end = range.start + new_pos + 1;
-                                    found = true;
-                                }
-                                break;
-                            }
-                        }
-                        if !found {
-                            break;
-                        }
-                    }
-                    drop_tag(tags, tag_name, r, f);
-                } else {
-                    let mut is_self_closing = false;
-                    let mut quote_pos = None;
-                    if c != '>' {
-                        let mut quote = None;
-                        let mut after_eq = false;
-                        for (i, c) in text[pos..].char_indices() {
-                            if !c.is_whitespace() {
-                                if let Some(q) = quote {
-                                    if c == q {
-                                        quote = None;
-                                        quote_pos = None;
-                                        after_eq = false;
-                                    }
-                                } else if c == '>' {
-                                    break;
-                                } else if c == '/' && !after_eq {
-                                    is_self_closing = true;
-                                } else {
-                                    if is_self_closing {
-                                        is_self_closing = false;
-                                    }
-                                    if (c == '"' || c == '\'') && after_eq {
-                                        quote = Some(c);
-                                        quote_pos = Some(pos + i);
-                                    } else if c == '=' {
-                                        after_eq = true;
-                                    }
-                                }
-                            } else if quote.is_none() {
-                                after_eq = false;
-                            }
-                        }
-                    }
-                    if let Some(quote_pos) = quote_pos {
-                        let qr = Range { start: quote_pos, end: quote_pos };
-                        f(
-                            &format!("unclosed quoted HTML attribute on tag `{}`", tag_name),
-                            &qr,
-                            false,
-                        );
-                    }
-                    if is_self_closing {
-                        // https://html.spec.whatwg.org/#parse-error-non-void-html-element-start-tag-with-trailing-solidus
-                        let valid = ALLOWED_UNCLOSED.contains(&&tag_name[..])
-                            || tags.iter().take(pos + 1).any(|(at, _)| {
-                                let at = at.to_lowercase();
-                                at == "svg" || at == "math"
-                            });
-                        if !valid {
-                            f(&format!("invalid self-closing HTML tag `{}`", tag_name), &r, false);
-                        }
-                    } else {
-                        tags.push((tag_name, r));
-                    }
-                }
-            }
-            break;
-        }
-        iter.next();
-    }
-}
-
-fn extract_tags(
-    tags: &mut Vec<(String, Range<usize>)>,
-    text: &str,
-    range: Range<usize>,
-    is_in_comment: &mut Option<Range<usize>>,
-    f: &impl Fn(&str, &Range<usize>, bool),
-) {
-    let mut iter = text.char_indices().peekable();
-
-    while let Some((start_pos, c)) = iter.next() {
-        if is_in_comment.is_some() {
-            if text[start_pos..].starts_with("-->") {
-                *is_in_comment = None;
-            }
-        } else if c == '<' {
-            if text[start_pos..].starts_with("<!--") {
-                // We skip the "!--" part. (Once `advance_by` is stable, might be nice to use it!)
-                iter.next();
-                iter.next();
-                iter.next();
-                *is_in_comment = Some(Range {
-                    start: range.start + start_pos,
-                    end: range.start + start_pos + 3,
-                });
-            } else {
-                extract_html_tag(tags, text, &range, start_pos, &mut iter, f);
-            }
-        }
-    }
-}
-
-impl<'a, 'tcx> DocVisitor for InvalidHtmlTagsLinter<'a, 'tcx> {
-    fn visit_item(&mut self, item: &Item) {
-        let tcx = self.cx.tcx;
-        let Some(hir_id) = DocContext::as_local_hir_id(tcx, item.item_id)
-        // If non-local, no need to check anything.
-        else { return };
-        let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
-        if !dox.is_empty() {
-            let report_diag = |msg: &str, range: &Range<usize>, is_open_tag: bool| {
-                let sp = match super::source_span_for_markdown_range(tcx, &dox, range, &item.attrs)
-                {
-                    Some(sp) => sp,
-                    None => item.attr_span(tcx),
-                };
-                tcx.struct_span_lint_hir(crate::lint::INVALID_HTML_TAGS, hir_id, sp, msg, |lint| {
-                    use rustc_lint_defs::Applicability;
-                    // If a tag looks like `<this>`, it might actually be a generic.
-                    // We don't try to detect stuff `<like, this>` because that's not valid HTML,
-                    // and we don't try to detect stuff `<like this>` because that's not valid Rust.
-                    let mut generics_end = range.end;
-                    if let Some(Some(mut generics_start)) = (is_open_tag
-                        && dox[..generics_end].ends_with('>'))
-                    .then(|| extract_path_backwards(&dox, range.start))
-                    {
-                        while generics_start != 0
-                            && generics_end < dox.len()
-                            && dox.as_bytes()[generics_start - 1] == b'<'
-                            && dox.as_bytes()[generics_end] == b'>'
-                        {
-                            generics_end += 1;
-                            generics_start -= 1;
-                            if let Some(new_start) = extract_path_backwards(&dox, generics_start) {
-                                generics_start = new_start;
-                            }
-                            if let Some(new_end) = extract_path_forward(&dox, generics_end) {
-                                generics_end = new_end;
-                            }
-                        }
-                        if let Some(new_end) = extract_path_forward(&dox, generics_end) {
-                            generics_end = new_end;
-                        }
-                        let generics_sp = match super::source_span_for_markdown_range(
-                            tcx,
-                            &dox,
-                            &(generics_start..generics_end),
-                            &item.attrs,
-                        ) {
-                            Some(sp) => sp,
-                            None => item.attr_span(tcx),
-                        };
-                        // Sometimes, we only extract part of a path. For example, consider this:
-                        //
-                        //     <[u32] as IntoIter<u32>>::Item
-                        //                       ^^^^^ unclosed HTML tag `u32`
-                        //
-                        // We don't have any code for parsing fully-qualified trait paths.
-                        // In theory, we could add it, but doing it correctly would require
-                        // parsing the entire path grammar, which is problematic because of
-                        // overlap between the path grammar and Markdown.
-                        //
-                        // The example above shows that ambiguity. Is `[u32]` intended to be an
-                        // intra-doc link to the u32 primitive, or is it intended to be a slice?
-                        //
-                        // If the below conditional were removed, we would suggest this, which is
-                        // not what the user probably wants.
-                        //
-                        //     <[u32] as `IntoIter<u32>`>::Item
-                        //
-                        // We know that the user actually wants to wrap the whole thing in a code
-                        // block, but the only reason we know that is because `u32` does not, in
-                        // fact, implement IntoIter. If the example looks like this:
-                        //
-                        //     <[Vec<i32>] as IntoIter<i32>::Item
-                        //
-                        // The ideal fix would be significantly different.
-                        if (generics_start > 0 && dox.as_bytes()[generics_start - 1] == b'<')
-                            || (generics_end < dox.len() && dox.as_bytes()[generics_end] == b'>')
-                        {
-                            return lint;
-                        }
-                        // multipart form is chosen here because ``Vec<i32>`` would be confusing.
-                        lint.multipart_suggestion(
-                            "try marking as source code",
-                            vec![
-                                (generics_sp.shrink_to_lo(), String::from("`")),
-                                (generics_sp.shrink_to_hi(), String::from("`")),
-                            ],
-                            Applicability::MaybeIncorrect,
-                        );
-                    }
-
-                    lint
-                });
-            };
-
-            let mut tags = Vec::new();
-            let mut is_in_comment = None;
-            let mut in_code_block = false;
-
-            let link_names = item.link_names(&self.cx.cache);
-
-            let mut replacer = |broken_link: BrokenLink<'_>| {
-                if let Some(link) =
-                    link_names.iter().find(|link| *link.original_text == *broken_link.reference)
-                {
-                    Some((link.href.as_str().into(), link.new_text.as_str().into()))
-                } else if matches!(
-                    &broken_link.link_type,
-                    LinkType::Reference | LinkType::ReferenceUnknown
-                ) {
-                    // If the link is shaped [like][this], suppress any broken HTML in the [this] part.
-                    // The `broken_intra_doc_links` will report typos in there anyway.
-                    Some((
-                        broken_link.reference.to_string().into(),
-                        broken_link.reference.to_string().into(),
-                    ))
-                } else {
-                    None
-                }
-            };
-
-            let p =
-                Parser::new_with_broken_link_callback(&dox, main_body_opts(), Some(&mut replacer))
-                    .into_offset_iter();
-
-            for (event, range) in p {
-                match event {
-                    Event::Start(Tag::CodeBlock(_)) => in_code_block = true,
-                    Event::Html(text) if !in_code_block => {
-                        extract_tags(&mut tags, &text, range, &mut is_in_comment, &report_diag)
-                    }
-                    Event::End(Tag::CodeBlock(_)) => in_code_block = false,
-                    _ => {}
-                }
-            }
-
-            for (tag, range) in tags.iter().filter(|(t, _)| {
-                let t = t.to_lowercase();
-                !ALLOWED_UNCLOSED.contains(&t.as_str())
-            }) {
-                report_diag(&format!("unclosed HTML tag `{}`", tag), range, true);
-            }
-
-            if let Some(range) = is_in_comment {
-                report_diag("Unclosed HTML comment", &range, false);
-            }
-        }
-
-        self.visit_item_recur(item)
-    }
-}
diff --git a/src/librustdoc/passes/lint.rs b/src/librustdoc/passes/lint.rs
new file mode 100644
index 000000000..97031c4f0
--- /dev/null
+++ b/src/librustdoc/passes/lint.rs
@@ -0,0 +1,33 @@
+//! Runs several rustdoc lints, consolidating them into a single pass for
+//! efficiency and simplicity.
+
+mod bare_urls;
+mod check_code_block_syntax;
+mod html_tags;
+
+use super::Pass;
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::visit::DocVisitor;
+
+pub(crate) const RUN_LINTS: Pass =
+    Pass { name: "run-lints", run: run_lints, description: "runs some of rustdoc's lints" };
+
+struct Linter<'a, 'tcx> {
+    cx: &'a mut DocContext<'tcx>,
+}
+
+pub(crate) fn run_lints(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
+    Linter { cx }.visit_crate(&krate);
+    krate
+}
+
+impl<'a, 'tcx> DocVisitor for Linter<'a, 'tcx> {
+    fn visit_item(&mut self, item: &Item) {
+        bare_urls::visit_item(self.cx, item);
+        check_code_block_syntax::visit_item(self.cx, item);
+        html_tags::visit_item(self.cx, item);
+
+        self.visit_item_recur(item)
+    }
+}
diff --git a/src/librustdoc/passes/lint/bare_urls.rs b/src/librustdoc/passes/lint/bare_urls.rs
new file mode 100644
index 000000000..423230cfe
--- /dev/null
+++ b/src/librustdoc/passes/lint/bare_urls.rs
@@ -0,0 +1,89 @@
+//! Detects links that are not linkified, e.g., in Markdown such as `Go to https://example.com/.`
+//! Suggests wrapping the link with angle brackets: `Go to <https://example.com/>.` to linkify it.
+
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::html::markdown::main_body_opts;
+use crate::passes::source_span_for_markdown_range;
+use core::ops::Range;
+use pulldown_cmark::{Event, Parser, Tag};
+use regex::Regex;
+use rustc_errors::Applicability;
+use std::mem;
+use std::sync::LazyLock;
+
+pub(super) fn visit_item(cx: &DocContext<'_>, item: &Item) {
+    let Some(hir_id) = DocContext::as_local_hir_id(cx.tcx, item.item_id)
+        else {
+            // If non-local, no need to check anything.
+            return;
+        };
+    let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
+    if !dox.is_empty() {
+        let report_diag = |cx: &DocContext<'_>, msg: &str, url: &str, range: Range<usize>| {
+            let sp = source_span_for_markdown_range(cx.tcx, &dox, &range, &item.attrs)
+                .unwrap_or_else(|| item.attr_span(cx.tcx));
+            cx.tcx.struct_span_lint_hir(crate::lint::BARE_URLS, hir_id, sp, msg, |lint| {
+                lint.note("bare URLs are not automatically turned into clickable links")
+                    .span_suggestion(
+                        sp,
+                        "use an automatic link instead",
+                        format!("<{}>", url),
+                        Applicability::MachineApplicable,
+                    )
+            });
+        };
+
+        let mut p = Parser::new_ext(&dox, main_body_opts()).into_offset_iter();
+
+        while let Some((event, range)) = p.next() {
+            match event {
+                Event::Text(s) => find_raw_urls(cx, &s, range, &report_diag),
+                // We don't want to check the text inside code blocks or links.
+                Event::Start(tag @ (Tag::CodeBlock(_) | Tag::Link(..))) => {
+                    while let Some((event, _)) = p.next() {
+                        match event {
+                            Event::End(end)
+                                if mem::discriminant(&end) == mem::discriminant(&tag) =>
+                            {
+                                break;
+                            }
+                            _ => {}
+                        }
+                    }
+                }
+                _ => {}
+            }
+        }
+    }
+}
+
+static URL_REGEX: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(concat!(
+        r"https?://",                          // url scheme
+        r"([-a-zA-Z0-9@:%._\+~#=]{2,256}\.)+", // one or more subdomains
+        r"[a-zA-Z]{2,63}",                     // root domain
+        r"\b([-a-zA-Z0-9@:%_\+.~#?&/=]*)"      // optional query or url fragments
+    ))
+    .expect("failed to build regex")
+});
+
+fn find_raw_urls(
+    cx: &DocContext<'_>,
+    text: &str,
+    range: Range<usize>,
+    f: &impl Fn(&DocContext<'_>, &str, &str, Range<usize>),
+) {
+    trace!("looking for raw urls in {}", text);
+    // For now, we only check "full" URLs (meaning, starting with "http://" or "https://").
+    for match_ in URL_REGEX.find_iter(text) {
+        let url = match_.as_str();
+        let url_range = match_.range();
+        f(
+            cx,
+            "this URL is not a hyperlink",
+            url,
+            Range { start: range.start + url_range.start, end: range.start + url_range.end },
+        );
+    }
+}
diff --git a/src/librustdoc/passes/lint/check_code_block_syntax.rs b/src/librustdoc/passes/lint/check_code_block_syntax.rs
new file mode 100644
index 000000000..5aa4f238b
--- /dev/null
+++ b/src/librustdoc/passes/lint/check_code_block_syntax.rs
@@ -0,0 +1,170 @@
+//! Validates syntax inside Rust code blocks (\`\`\`rust).
+use rustc_data_structures::sync::{Lock, Lrc};
+use rustc_errors::{
+    emitter::Emitter,
+    translation::{to_fluent_args, Translate},
+    Applicability, Diagnostic, Handler, LazyFallbackBundle,
+};
+use rustc_parse::parse_stream_from_source_str;
+use rustc_session::parse::ParseSess;
+use rustc_span::hygiene::{AstPass, ExpnData, ExpnKind, LocalExpnId};
+use rustc_span::source_map::{FilePathMapping, SourceMap};
+use rustc_span::{FileName, InnerSpan, DUMMY_SP};
+
+use crate::clean;
+use crate::core::DocContext;
+use crate::html::markdown::{self, RustCodeBlock};
+use crate::passes::source_span_for_markdown_range;
+
+pub(crate) fn visit_item(cx: &DocContext<'_>, item: &clean::Item) {
+    if let Some(dox) = &item.attrs.collapsed_doc_value() {
+        let sp = item.attr_span(cx.tcx);
+        let extra =
+            crate::html::markdown::ExtraInfo::new_did(cx.tcx, item.item_id.expect_def_id(), sp);
+        for code_block in markdown::rust_code_blocks(dox, &extra) {
+            check_rust_syntax(cx, item, dox, code_block);
+        }
+    }
+}
+
+fn check_rust_syntax(
+    cx: &DocContext<'_>,
+    item: &clean::Item,
+    dox: &str,
+    code_block: RustCodeBlock,
+) {
+    let buffer = Lrc::new(Lock::new(Buffer::default()));
+    let fallback_bundle =
+        rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
+    let emitter = BufferEmitter { buffer: Lrc::clone(&buffer), fallback_bundle };
+
+    let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+    let handler = Handler::with_emitter(false, None, Box::new(emitter));
+    let source = dox[code_block.code].to_owned();
+    let sess = ParseSess::with_span_handler(handler, sm);
+
+    let edition = code_block.lang_string.edition.unwrap_or_else(|| cx.tcx.sess.edition());
+    let expn_data =
+        ExpnData::default(ExpnKind::AstPass(AstPass::TestHarness), DUMMY_SP, edition, None, None);
+    let expn_id = cx.tcx.with_stable_hashing_context(|hcx| LocalExpnId::fresh(expn_data, hcx));
+    let span = DUMMY_SP.fresh_expansion(expn_id);
+
+    let is_empty = rustc_driver::catch_fatal_errors(|| {
+        parse_stream_from_source_str(
+            FileName::Custom(String::from("doctest")),
+            source,
+            &sess,
+            Some(span),
+        )
+        .is_empty()
+    })
+    .unwrap_or(false);
+    let buffer = buffer.borrow();
+
+    if !buffer.has_errors && !is_empty {
+        // No errors in a non-empty program.
+        return;
+    }
+
+    let Some(local_id) = item.item_id.as_def_id().and_then(|x| x.as_local())
+        else {
+            // We don't need to check the syntax for other crates so returning
+            // without doing anything should not be a problem.
+            return;
+        };
+
+    let hir_id = cx.tcx.hir().local_def_id_to_hir_id(local_id);
+    let empty_block = code_block.lang_string == Default::default() && code_block.is_fenced;
+    let is_ignore = code_block.lang_string.ignore != markdown::Ignore::None;
+
+    // The span and whether it is precise or not.
+    let (sp, precise_span) =
+        match source_span_for_markdown_range(cx.tcx, dox, &code_block.range, &item.attrs) {
+            Some(sp) => (sp, true),
+            None => (item.attr_span(cx.tcx), false),
+        };
+
+    let msg = if buffer.has_errors {
+        "could not parse code block as Rust code"
+    } else {
+        "Rust code block is empty"
+    };
+
+    // Finally build and emit the completed diagnostic.
+    // All points of divergence have been handled earlier so this can be
+    // done the same way whether the span is precise or not.
+    cx.tcx.struct_span_lint_hir(crate::lint::INVALID_RUST_CODEBLOCKS, hir_id, sp, msg, |lint| {
+        let explanation = if is_ignore {
+            "`ignore` code blocks require valid Rust code for syntax highlighting; \
+                    mark blocks that do not contain Rust code as text"
+        } else {
+            "mark blocks that do not contain Rust code as text"
+        };
+
+        if precise_span {
+            if is_ignore {
+                // giving an accurate suggestion is hard because `ignore` might not have come first in the list.
+                // just give a `help` instead.
+                lint.span_help(
+                    sp.from_inner(InnerSpan::new(0, 3)),
+                    &format!("{}: ```text", explanation),
+                );
+            } else if empty_block {
+                lint.span_suggestion(
+                    sp.from_inner(InnerSpan::new(0, 3)).shrink_to_hi(),
+                    explanation,
+                    "text",
+                    Applicability::MachineApplicable,
+                );
+            }
+        } else if empty_block || is_ignore {
+            lint.help(&format!("{}: ```text", explanation));
+        }
+
+        // FIXME(#67563): Provide more context for these errors by displaying the spans inline.
+        for message in buffer.messages.iter() {
+            lint.note(message);
+        }
+
+        lint
+    });
+}
+
+#[derive(Default)]
+struct Buffer {
+    messages: Vec<String>,
+    has_errors: bool,
+}
+
+struct BufferEmitter {
+    buffer: Lrc<Lock<Buffer>>,
+    fallback_bundle: LazyFallbackBundle,
+}
+
+impl Translate for BufferEmitter {
+    fn fluent_bundle(&self) -> Option<&Lrc<rustc_errors::FluentBundle>> {
+        None
+    }
+
+    fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
+        &**self.fallback_bundle
+    }
+}
+
+impl Emitter for BufferEmitter {
+    fn emit_diagnostic(&mut self, diag: &Diagnostic) {
+        let mut buffer = self.buffer.borrow_mut();
+
+        let fluent_args = to_fluent_args(diag.args());
+        let translated_main_message = self.translate_message(&diag.message[0].0, &fluent_args);
+
+        buffer.messages.push(format!("error from rustc: {}", translated_main_message));
+        if diag.is_error() {
+            buffer.has_errors = true;
+        }
+    }
+
+    fn source_map(&self) -> Option<&Lrc<SourceMap>> {
+        None
+    }
+}
diff --git a/src/librustdoc/passes/lint/html_tags.rs b/src/librustdoc/passes/lint/html_tags.rs
new file mode 100644
index 000000000..070c0aab5
--- /dev/null
+++ b/src/librustdoc/passes/lint/html_tags.rs
@@ -0,0 +1,407 @@
+//! Detects invalid HTML (like an unclosed `<span>`) in doc comments.
+use crate::clean::*;
+use crate::core::DocContext;
+use crate::html::markdown::main_body_opts;
+use crate::passes::source_span_for_markdown_range;
+
+use pulldown_cmark::{BrokenLink, Event, LinkType, Parser, Tag};
+
+use std::iter::Peekable;
+use std::ops::Range;
+use std::str::CharIndices;
+
+pub(crate) fn visit_item(cx: &DocContext<'_>, item: &Item) {
+    let tcx = cx.tcx;
+    let Some(hir_id) = DocContext::as_local_hir_id(tcx, item.item_id)
+    // If non-local, no need to check anything.
+    else { return };
+    let dox = item.attrs.collapsed_doc_value().unwrap_or_default();
+    if !dox.is_empty() {
+        let report_diag = |msg: &str, range: &Range<usize>, is_open_tag: bool| {
+            let sp = match source_span_for_markdown_range(tcx, &dox, range, &item.attrs) {
+                Some(sp) => sp,
+                None => item.attr_span(tcx),
+            };
+            tcx.struct_span_lint_hir(crate::lint::INVALID_HTML_TAGS, hir_id, sp, msg, |lint| {
+                use rustc_lint_defs::Applicability;
+                // If a tag looks like `<this>`, it might actually be a generic.
+                // We don't try to detect stuff `<like, this>` because that's not valid HTML,
+                // and we don't try to detect stuff `<like this>` because that's not valid Rust.
+                let mut generics_end = range.end;
+                if let Some(Some(mut generics_start)) = (is_open_tag
+                    && dox[..generics_end].ends_with('>'))
+                .then(|| extract_path_backwards(&dox, range.start))
+                {
+                    while generics_start != 0
+                        && generics_end < dox.len()
+                        && dox.as_bytes()[generics_start - 1] == b'<'
+                        && dox.as_bytes()[generics_end] == b'>'
+                    {
+                        generics_end += 1;
+                        generics_start -= 1;
+                        if let Some(new_start) = extract_path_backwards(&dox, generics_start) {
+                            generics_start = new_start;
+                        }
+                        if let Some(new_end) = extract_path_forward(&dox, generics_end) {
+                            generics_end = new_end;
+                        }
+                    }
+                    if let Some(new_end) = extract_path_forward(&dox, generics_end) {
+                        generics_end = new_end;
+                    }
+                    let generics_sp = match source_span_for_markdown_range(
+                        tcx,
+                        &dox,
+                        &(generics_start..generics_end),
+                        &item.attrs,
+                    ) {
+                        Some(sp) => sp,
+                        None => item.attr_span(tcx),
+                    };
+                    // Sometimes, we only extract part of a path. For example, consider this:
+                    //
+                    //     <[u32] as IntoIter<u32>>::Item
+                    //                       ^^^^^ unclosed HTML tag `u32`
+                    //
+                    // We don't have any code for parsing fully-qualified trait paths.
+                    // In theory, we could add it, but doing it correctly would require
+                    // parsing the entire path grammar, which is problematic because of
+                    // overlap between the path grammar and Markdown.
+                    //
+                    // The example above shows that ambiguity. Is `[u32]` intended to be an
+                    // intra-doc link to the u32 primitive, or is it intended to be a slice?
+                    //
+                    // If the below conditional were removed, we would suggest this, which is
+                    // not what the user probably wants.
+                    //
+                    //     <[u32] as `IntoIter<u32>`>::Item
+                    //
+                    // We know that the user actually wants to wrap the whole thing in a code
+                    // block, but the only reason we know that is because `u32` does not, in
+                    // fact, implement IntoIter. If the example looks like this:
+                    //
+                    //     <[Vec<i32>] as IntoIter<i32>::Item
+                    //
+                    // The ideal fix would be significantly different.
+                    if (generics_start > 0 && dox.as_bytes()[generics_start - 1] == b'<')
+                        || (generics_end < dox.len() && dox.as_bytes()[generics_end] == b'>')
+                    {
+                        return lint;
+                    }
+                    // multipart form is chosen here because ``Vec<i32>`` would be confusing.
+                    lint.multipart_suggestion(
+                        "try marking as source code",
+                        vec![
+                            (generics_sp.shrink_to_lo(), String::from("`")),
+                            (generics_sp.shrink_to_hi(), String::from("`")),
+                        ],
+                        Applicability::MaybeIncorrect,
+                    );
+                }
+
+                lint
+            });
+        };
+
+        let mut tags = Vec::new();
+        let mut is_in_comment = None;
+        let mut in_code_block = false;
+
+        let link_names = item.link_names(&cx.cache);
+
+        let mut replacer = |broken_link: BrokenLink<'_>| {
+            if let Some(link) =
+                link_names.iter().find(|link| *link.original_text == *broken_link.reference)
+            {
+                Some((link.href.as_str().into(), link.new_text.as_str().into()))
+            } else if matches!(
+                &broken_link.link_type,
+                LinkType::Reference | LinkType::ReferenceUnknown
+            ) {
+                // If the link is shaped [like][this], suppress any broken HTML in the [this] part.
+                // The `broken_intra_doc_links` will report typos in there anyway.
+                Some((
+                    broken_link.reference.to_string().into(),
+                    broken_link.reference.to_string().into(),
+                ))
+            } else {
+                None
+            }
+        };
+
+        let p = Parser::new_with_broken_link_callback(&dox, main_body_opts(), Some(&mut replacer))
+            .into_offset_iter();
+
+        for (event, range) in p {
+            match event {
+                Event::Start(Tag::CodeBlock(_)) => in_code_block = true,
+                Event::Html(text) if !in_code_block => {
+                    extract_tags(&mut tags, &text, range, &mut is_in_comment, &report_diag)
+                }
+                Event::End(Tag::CodeBlock(_)) => in_code_block = false,
+                _ => {}
+            }
+        }
+
+        for (tag, range) in tags.iter().filter(|(t, _)| {
+            let t = t.to_lowercase();
+            !ALLOWED_UNCLOSED.contains(&t.as_str())
+        }) {
+            report_diag(&format!("unclosed HTML tag `{}`", tag), range, true);
+        }
+
+        if let Some(range) = is_in_comment {
+            report_diag("Unclosed HTML comment", &range, false);
+        }
+    }
+}
+
+const ALLOWED_UNCLOSED: &[&str] = &[
+    "area", "base", "br", "col", "embed", "hr", "img", "input", "keygen", "link", "meta", "param",
+    "source", "track", "wbr",
+];
+
+fn drop_tag(
+    tags: &mut Vec<(String, Range<usize>)>,
+    tag_name: String,
+    range: Range<usize>,
+    f: &impl Fn(&str, &Range<usize>, bool),
+) {
+    let tag_name_low = tag_name.to_lowercase();
+    if let Some(pos) = tags.iter().rposition(|(t, _)| t.to_lowercase() == tag_name_low) {
+        // If the tag is nested inside a "<script>" or a "<style>" tag, no warning should
+        // be emitted.
+        let should_not_warn = tags.iter().take(pos + 1).any(|(at, _)| {
+            let at = at.to_lowercase();
+            at == "script" || at == "style"
+        });
+        for (last_tag_name, last_tag_span) in tags.drain(pos + 1..) {
+            if should_not_warn {
+                continue;
+            }
+            let last_tag_name_low = last_tag_name.to_lowercase();
+            if ALLOWED_UNCLOSED.contains(&last_tag_name_low.as_str()) {
+                continue;
+            }
+            // `tags` is used as a queue, meaning that everything after `pos` is included inside it.
+            // So `<h2><h3></h2>` will look like `["h2", "h3"]`. So when closing `h2`, we will still
+            // have `h3`, meaning the tag wasn't closed as it should have.
+            f(&format!("unclosed HTML tag `{}`", last_tag_name), &last_tag_span, true);
+        }
+        // Remove the `tag_name` that was originally closed
+        tags.pop();
+    } else {
+        // It can happen for example in this case: `<h2></script></h2>` (the `h2` tag isn't required
+        // but it helps for the visualization).
+        f(&format!("unopened HTML tag `{}`", tag_name), &range, false);
+    }
+}
+
+fn extract_path_backwards(text: &str, end_pos: usize) -> Option<usize> {
+    use rustc_lexer::{is_id_continue, is_id_start};
+    let mut current_pos = end_pos;
+    loop {
+        if current_pos >= 2 && text[..current_pos].ends_with("::") {
+            current_pos -= 2;
+        }
+        let new_pos = text[..current_pos]
+            .char_indices()
+            .rev()
+            .take_while(|(_, c)| is_id_start(*c) || is_id_continue(*c))
+            .reduce(|_accum, item| item)
+            .and_then(|(new_pos, c)| is_id_start(c).then_some(new_pos));
+        if let Some(new_pos) = new_pos {
+            if current_pos != new_pos {
+                current_pos = new_pos;
+                continue;
+            }
+        }
+        break;
+    }
+    if current_pos == end_pos { None } else { Some(current_pos) }
+}
+
+fn extract_path_forward(text: &str, start_pos: usize) -> Option<usize> {
+    use rustc_lexer::{is_id_continue, is_id_start};
+    let mut current_pos = start_pos;
+    loop {
+        if current_pos < text.len() && text[current_pos..].starts_with("::") {
+            current_pos += 2;
+        } else {
+            break;
+        }
+        let mut chars = text[current_pos..].chars();
+        if let Some(c) = chars.next() {
+            if is_id_start(c) {
+                current_pos += c.len_utf8();
+            } else {
+                break;
+            }
+        }
+        while let Some(c) = chars.next() {
+            if is_id_continue(c) {
+                current_pos += c.len_utf8();
+            } else {
+                break;
+            }
+        }
+    }
+    if current_pos == start_pos { None } else { Some(current_pos) }
+}
+
+fn is_valid_for_html_tag_name(c: char, is_empty: bool) -> bool {
+    // https://spec.commonmark.org/0.30/#raw-html
+    //
+    // > A tag name consists of an ASCII letter followed by zero or more ASCII letters, digits, or
+    // > hyphens (-).
+    c.is_ascii_alphabetic() || !is_empty && (c == '-' || c.is_ascii_digit())
+}
+
+fn extract_html_tag(
+    tags: &mut Vec<(String, Range<usize>)>,
+    text: &str,
+    range: &Range<usize>,
+    start_pos: usize,
+    iter: &mut Peekable<CharIndices<'_>>,
+    f: &impl Fn(&str, &Range<usize>, bool),
+) {
+    let mut tag_name = String::new();
+    let mut is_closing = false;
+    let mut prev_pos = start_pos;
+
+    loop {
+        let (pos, c) = match iter.peek() {
+            Some((pos, c)) => (*pos, *c),
+            // In case we reached the of the doc comment, we want to check that it's an
+            // unclosed HTML tag. For example "/// <h3".
+            None => (prev_pos, '\0'),
+        };
+        prev_pos = pos;
+        // Checking if this is a closing tag (like `</a>` for `<a>`).
+        if c == '/' && tag_name.is_empty() {
+            is_closing = true;
+        } else if is_valid_for_html_tag_name(c, tag_name.is_empty()) {
+            tag_name.push(c);
+        } else {
+            if !tag_name.is_empty() {
+                let mut r = Range { start: range.start + start_pos, end: range.start + pos };
+                if c == '>' {
+                    // In case we have a tag without attribute, we can consider the span to
+                    // refer to it fully.
+                    r.end += 1;
+                }
+                if is_closing {
+                    // In case we have "</div >" or even "</div         >".
+                    if c != '>' {
+                        if !c.is_whitespace() {
+                            // It seems like it's not a valid HTML tag.
+                            break;
+                        }
+                        let mut found = false;
+                        for (new_pos, c) in text[pos..].char_indices() {
+                            if !c.is_whitespace() {
+                                if c == '>' {
+                                    r.end = range.start + new_pos + 1;
+                                    found = true;
+                                }
+                                break;
+                            }
+                        }
+                        if !found {
+                            break;
+                        }
+                    }
+                    drop_tag(tags, tag_name, r, f);
+                } else {
+                    let mut is_self_closing = false;
+                    let mut quote_pos = None;
+                    if c != '>' {
+                        let mut quote = None;
+                        let mut after_eq = false;
+                        for (i, c) in text[pos..].char_indices() {
+                            if !c.is_whitespace() {
+                                if let Some(q) = quote {
+                                    if c == q {
+                                        quote = None;
+                                        quote_pos = None;
+                                        after_eq = false;
+                                    }
+                                } else if c == '>' {
+                                    break;
+                                } else if c == '/' && !after_eq {
+                                    is_self_closing = true;
+                                } else {
+                                    if is_self_closing {
+                                        is_self_closing = false;
+                                    }
+                                    if (c == '"' || c == '\'') && after_eq {
+                                        quote = Some(c);
+                                        quote_pos = Some(pos + i);
+                                    } else if c == '=' {
+                                        after_eq = true;
+                                    }
+                                }
+                            } else if quote.is_none() {
+                                after_eq = false;
+                            }
+                        }
+                    }
+                    if let Some(quote_pos) = quote_pos {
+                        let qr = Range { start: quote_pos, end: quote_pos };
+                        f(
+                            &format!("unclosed quoted HTML attribute on tag `{}`", tag_name),
+                            &qr,
+                            false,
+                        );
+                    }
+                    if is_self_closing {
+                        // https://html.spec.whatwg.org/#parse-error-non-void-html-element-start-tag-with-trailing-solidus
+                        let valid = ALLOWED_UNCLOSED.contains(&&tag_name[..])
+                            || tags.iter().take(pos + 1).any(|(at, _)| {
+                                let at = at.to_lowercase();
+                                at == "svg" || at == "math"
+                            });
+                        if !valid {
+                            f(&format!("invalid self-closing HTML tag `{}`", tag_name), &r, false);
+                        }
+                    } else {
+                        tags.push((tag_name, r));
+                    }
+                }
+            }
+            break;
+        }
+        iter.next();
+    }
+}
+
+fn extract_tags(
+    tags: &mut Vec<(String, Range<usize>)>,
+    text: &str,
+    range: Range<usize>,
+    is_in_comment: &mut Option<Range<usize>>,
+    f: &impl Fn(&str, &Range<usize>, bool),
+) {
+    let mut iter = text.char_indices().peekable();
+
+    while let Some((start_pos, c)) = iter.next() {
+        if is_in_comment.is_some() {
+            if text[start_pos..].starts_with("-->") {
+                *is_in_comment = None;
+            }
+        } else if c == '<' {
+            if text[start_pos..].starts_with("<!--") {
+                // We skip the "!--" part. (Once `advance_by` is stable, might be nice to use it!)
+                iter.next();
+                iter.next();
+                iter.next();
+                *is_in_comment = Some(Range {
+                    start: range.start + start_pos,
+                    end: range.start + start_pos + 3,
+                });
+            } else {
+                extract_html_tag(tags, text, &range, start_pos, &mut iter, f);
+            }
+        }
+    }
+}
diff --git a/src/librustdoc/passes/mod.rs b/src/librustdoc/passes/mod.rs
index f81b38ea3..634e70ec9 100644
--- a/src/librustdoc/passes/mod.rs
+++ b/src/librustdoc/passes/mod.rs
@@ -12,9 +12,6 @@ use crate::core::DocContext;
 mod stripper;
 pub(crate) use stripper::*;
 
-mod bare_urls;
-pub(crate) use self::bare_urls::CHECK_BARE_URLS;
-
 mod strip_hidden;
 pub(crate) use self::strip_hidden::STRIP_HIDDEN;
 
@@ -36,14 +33,11 @@ pub(crate) use self::check_doc_test_visibility::CHECK_DOC_TEST_VISIBILITY;
 mod collect_trait_impls;
 pub(crate) use self::collect_trait_impls::COLLECT_TRAIT_IMPLS;
 
-mod check_code_block_syntax;
-pub(crate) use self::check_code_block_syntax::CHECK_CODE_BLOCK_SYNTAX;
-
 mod calculate_doc_coverage;
 pub(crate) use self::calculate_doc_coverage::CALCULATE_DOC_COVERAGE;
 
-mod html_tags;
-pub(crate) use self::html_tags::CHECK_INVALID_HTML_TAGS;
+mod lint;
+pub(crate) use self::lint::RUN_LINTS;
 
 /// A single pass over the cleaned documentation.
 ///
@@ -82,11 +76,9 @@ pub(crate) const PASSES: &[Pass] = &[
     STRIP_PRIV_IMPORTS,
     PROPAGATE_DOC_CFG,
     COLLECT_INTRA_DOC_LINKS,
-    CHECK_CODE_BLOCK_SYNTAX,
     COLLECT_TRAIT_IMPLS,
     CALCULATE_DOC_COVERAGE,
-    CHECK_INVALID_HTML_TAGS,
-    CHECK_BARE_URLS,
+    RUN_LINTS,
 ];
 
 /// The list of passes run by default.
@@ -97,10 +89,8 @@ pub(crate) const DEFAULT_PASSES: &[ConditionalPass] = &[
     ConditionalPass::new(STRIP_PRIVATE, WhenNotDocumentPrivate),
     ConditionalPass::new(STRIP_PRIV_IMPORTS, WhenDocumentPrivate),
     ConditionalPass::always(COLLECT_INTRA_DOC_LINKS),
-    ConditionalPass::always(CHECK_CODE_BLOCK_SYNTAX),
-    ConditionalPass::always(CHECK_INVALID_HTML_TAGS),
     ConditionalPass::always(PROPAGATE_DOC_CFG),
-    ConditionalPass::always(CHECK_BARE_URLS),
+    ConditionalPass::always(RUN_LINTS),
 ];
 
 /// The list of default passes run when `--doc-coverage` is passed to rustdoc.
diff --git a/src/librustdoc/passes/strip_hidden.rs b/src/librustdoc/passes/strip_hidden.rs
index 9914edf30..e07a788a7 100644
--- a/src/librustdoc/passes/strip_hidden.rs
+++ b/src/librustdoc/passes/strip_hidden.rs
@@ -27,6 +27,7 @@ pub(crate) fn strip_hidden(krate: clean::Crate, cx: &mut DocContext<'_>) -> clea
 
     // strip all impls referencing stripped items
     let mut stripper = ImplStripper {
+        tcx: cx.tcx,
         retained: &retained,
         cache: &cx.cache,
         is_json_output,
diff --git a/src/librustdoc/passes/strip_priv_imports.rs b/src/librustdoc/passes/strip_priv_imports.rs
index 85be8fa10..3bac5a8e5 100644
--- a/src/librustdoc/passes/strip_priv_imports.rs
+++ b/src/librustdoc/passes/strip_priv_imports.rs
@@ -11,6 +11,6 @@ pub(crate) const STRIP_PRIV_IMPORTS: Pass = Pass {
     description: "strips all private import statements (`use`, `extern crate`) from a crate",
 };
 
-pub(crate) fn strip_priv_imports(krate: clean::Crate, _: &mut DocContext<'_>) -> clean::Crate {
-    ImportStripper.fold_crate(krate)
+pub(crate) fn strip_priv_imports(krate: clean::Crate, cx: &mut DocContext<'_>) -> clean::Crate {
+    ImportStripper { tcx: cx.tcx }.fold_crate(krate)
 }
diff --git a/src/librustdoc/passes/strip_private.rs b/src/librustdoc/passes/strip_private.rs
index 450f69e15..8fc42462d 100644
--- a/src/librustdoc/passes/strip_private.rs
+++ b/src/librustdoc/passes/strip_private.rs
@@ -26,12 +26,14 @@ pub(crate) fn strip_private(mut krate: clean::Crate, cx: &mut DocContext<'_>) ->
             effective_visibilities: &cx.cache.effective_visibilities,
             update_retained: true,
             is_json_output,
+            tcx: cx.tcx,
         };
-        krate = ImportStripper.fold_crate(stripper.fold_crate(krate));
+        krate = ImportStripper { tcx: cx.tcx }.fold_crate(stripper.fold_crate(krate));
     }
 
     // strip all impls referencing private items
     let mut stripper = ImplStripper {
+        tcx: cx.tcx,
         retained: &retained,
         cache: &cx.cache,
         is_json_output,
diff --git a/src/librustdoc/passes/stripper.rs b/src/librustdoc/passes/stripper.rs
index 0089ce63d..995fb5dcc 100644
--- a/src/librustdoc/passes/stripper.rs
+++ b/src/librustdoc/passes/stripper.rs
@@ -1,19 +1,20 @@
 //! A collection of utility functions for the `strip_*` passes.
 use rustc_hir::def_id::DefId;
-use rustc_middle::middle::privacy::EffectiveVisibilities;
+use rustc_middle::ty::{TyCtxt, Visibility};
 use rustc_span::symbol::sym;
-
 use std::mem;
 
 use crate::clean::{self, Item, ItemId, ItemIdSet, NestedAttributesExt};
 use crate::fold::{strip_item, DocFolder};
 use crate::formats::cache::Cache;
+use crate::visit_lib::RustdocEffectiveVisibilities;
 
-pub(crate) struct Stripper<'a> {
+pub(crate) struct Stripper<'a, 'tcx> {
     pub(crate) retained: &'a mut ItemIdSet,
-    pub(crate) effective_visibilities: &'a EffectiveVisibilities<DefId>,
+    pub(crate) effective_visibilities: &'a RustdocEffectiveVisibilities,
     pub(crate) update_retained: bool,
     pub(crate) is_json_output: bool,
+    pub(crate) tcx: TyCtxt<'tcx>,
 }
 
 // We need to handle this differently for the JSON output because some non exported items could
@@ -21,18 +22,19 @@ pub(crate) struct Stripper<'a> {
 // are in the public API, which is not enough.
 #[inline]
 fn is_item_reachable(
+    tcx: TyCtxt<'_>,
     is_json_output: bool,
-    effective_visibilities: &EffectiveVisibilities<DefId>,
+    effective_visibilities: &RustdocEffectiveVisibilities,
     item_id: ItemId,
 ) -> bool {
     if is_json_output {
-        effective_visibilities.is_reachable(item_id.expect_def_id())
+        effective_visibilities.is_reachable(tcx, item_id.expect_def_id())
     } else {
-        effective_visibilities.is_exported(item_id.expect_def_id())
+        effective_visibilities.is_exported(tcx, item_id.expect_def_id())
     }
 }
 
-impl<'a> DocFolder for Stripper<'a> {
+impl<'a, 'tcx> DocFolder for Stripper<'a, 'tcx> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         match *i.kind {
             clean::StrippedItem(..) => {
@@ -66,7 +68,12 @@ impl<'a> DocFolder for Stripper<'a> {
             | clean::ForeignTypeItem => {
                 let item_id = i.item_id;
                 if item_id.is_local()
-                    && !is_item_reachable(self.is_json_output, self.effective_visibilities, item_id)
+                    && !is_item_reachable(
+                        self.tcx,
+                        self.is_json_output,
+                        self.effective_visibilities,
+                        item_id,
+                    )
                 {
                     debug!("Stripper: stripping {:?} {:?}", i.type_(), i.name);
                     return None;
@@ -74,13 +81,13 @@ impl<'a> DocFolder for Stripper<'a> {
             }
 
             clean::StructFieldItem(..) => {
-                if !i.visibility.is_public() {
+                if i.visibility(self.tcx) != Some(Visibility::Public) {
                     return Some(strip_item(i));
                 }
             }
 
             clean::ModuleItem(..) => {
-                if i.item_id.is_local() && !i.visibility.is_public() {
+                if i.item_id.is_local() && i.visibility(self.tcx) != Some(Visibility::Public) {
                     debug!("Stripper: stripping module {:?}", i.name);
                     let old = mem::replace(&mut self.update_retained, false);
                     let ret = strip_item(self.fold_item_recur(i));
@@ -146,14 +153,15 @@ impl<'a> DocFolder for Stripper<'a> {
 }
 
 /// This stripper discards all impls which reference stripped items
-pub(crate) struct ImplStripper<'a> {
+pub(crate) struct ImplStripper<'a, 'tcx> {
+    pub(crate) tcx: TyCtxt<'tcx>,
     pub(crate) retained: &'a ItemIdSet,
     pub(crate) cache: &'a Cache,
     pub(crate) is_json_output: bool,
     pub(crate) document_private: bool,
 }
 
-impl<'a> ImplStripper<'a> {
+impl<'a> ImplStripper<'a, '_> {
     #[inline]
     fn should_keep_impl(&self, item: &Item, for_def_id: DefId) -> bool {
         if !for_def_id.is_local() || self.retained.contains(&for_def_id.into()) {
@@ -161,7 +169,7 @@ impl<'a> ImplStripper<'a> {
         } else if self.is_json_output {
             // If the "for" item is exported and the impl block isn't `#[doc(hidden)]`, then we
             // need to keep it.
-            self.cache.effective_visibilities.is_exported(for_def_id)
+            self.cache.effective_visibilities.is_exported(self.tcx, for_def_id)
                 && !item.attrs.lists(sym::doc).has_word(sym::hidden)
         } else {
             false
@@ -169,7 +177,7 @@ impl<'a> ImplStripper<'a> {
     }
 }
 
-impl<'a> DocFolder for ImplStripper<'a> {
+impl<'a> DocFolder for ImplStripper<'a, '_> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         if let clean::ImplItem(ref imp) = *i.kind {
             // Impl blocks can be skipped if they are: empty; not a trait impl; and have no
@@ -185,6 +193,7 @@ impl<'a> DocFolder for ImplStripper<'a> {
                         let item_id = i.item_id;
                         item_id.is_local()
                             && !is_item_reachable(
+                                self.tcx,
                                 self.is_json_output,
                                 &self.cache.effective_visibilities,
                                 item_id,
@@ -229,12 +238,16 @@ impl<'a> DocFolder for ImplStripper<'a> {
 }
 
 /// This stripper discards all private import statements (`use`, `extern crate`)
-pub(crate) struct ImportStripper;
+pub(crate) struct ImportStripper<'tcx> {
+    pub(crate) tcx: TyCtxt<'tcx>,
+}
 
-impl DocFolder for ImportStripper {
+impl<'tcx> DocFolder for ImportStripper<'tcx> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         match *i.kind {
-            clean::ExternCrateItem { .. } | clean::ImportItem(..) if !i.visibility.is_public() => {
+            clean::ExternCrateItem { .. } | clean::ImportItem(..)
+                if i.visibility(self.tcx) != Some(Visibility::Public) =>
+            {
                 None
             }
             _ => Some(self.fold_item_recur(i)),
-- 
cgit v1.2.3