//! 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 .` to linkify it.
use crate::clean::*;
use crate::core::DocContext;
use crate::html::markdown::main_body_opts;
use core::ops::Range;
use pulldown_cmark::{Event, Parser, Tag};
use regex::Regex;
use rustc_errors::Applicability;
use rustc_resolve::rustdoc::source_span_for_markdown_range;
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.doc_value();
if !dox.is_empty() {
let report_diag =
|cx: &DocContext<'_>, msg: &'static str, url: &str, range: Range| {
let sp =
source_span_for_markdown_range(cx.tcx, &dox, &range, &item.attrs.doc_strings)
.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 = 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,
f: &impl Fn(&DocContext<'_>, &'static str, &str, Range),
) {
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 },
);
}
}