From 4547b622d8d29df964fa2914213088b148c498fc Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:18:32 +0200 Subject: Merging upstream version 1.67.1+dfsg1. Signed-off-by: Daniel Baumann --- src/librustdoc/passes/lint/html_tags.rs | 407 ++++++++++++++++++++++++++++++++ 1 file changed, 407 insertions(+) create mode 100644 src/librustdoc/passes/lint/html_tags.rs (limited to 'src/librustdoc/passes/lint/html_tags.rs') 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 ``) 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, 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 ``, it might actually be a generic. + // We don't try to detect stuff `` because that's not valid HTML, + // and we don't try to detect stuff `` 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>::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`>::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] as IntoIter::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`` 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)>, + tag_name: String, + range: Range, + f: &impl Fn(&str, &Range, 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 "` (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 { + 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 { + 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)>, + text: &str, + range: &Range, + start_pos: usize, + iter: &mut Peekable>, + f: &impl Fn(&str, &Range, 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 "/// (prev_pos, '\0'), + }; + prev_pos = pos; + // Checking if this is a closing tag (like `` for ``). + 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 "" or even "". + 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)>, + text: &str, + range: Range, + is_in_comment: &mut Option>, + f: &impl Fn(&str, &Range, 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("