too_long_first_doc_paragraph considers rendered output link

clippy_lints/Cargo.toml

@@ -21,7 +21,7 @@ serde = { version = "1.0", features = ["derive"] }
 serde_json = { version = "1.0", optional = true }
 tempfile = { version = "3.3.0", optional = true }
 toml = "0.7.3"
-regex = { version = "1.5", optional = true }
+regex = "1.5"
 unicode-normalization = "0.1"
 unicode-script = { version = "0.5", default-features = false }
 semver = "1.0"
@@ -32,7 +32,7 @@ walkdir = "2.3"
 
 [features]
 # build clippy with internal lints enabled, off by default
-internal = ["serde_json", "tempfile", "regex"]
+internal = ["serde_json", "tempfile"]
 
 [package.metadata.rust-analyzer]
 # This crate uses #[feature(rustc_private)]

clippy_lints/src/doc/mod.rs

@@ -14,6 +14,7 @@ use pulldown_cmark::Event::{
 };
 use pulldown_cmark::Tag::{BlockQuote, CodeBlock, FootnoteDefinition, Heading, Item, Link, Paragraph};
 use pulldown_cmark::{BrokenLink, CodeBlockKind, CowStr, Options, TagEnd};
+use regex::Regex;
 use rustc_ast::ast::Attribute;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::intravisit::{self, Visitor};
@@ -845,7 +846,9 @@ fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize
                 ticks_unbalanced = false;
                 paragraph_range = range;
                 if is_first_paragraph {
-                    headers.first_paragraph_len = doc[paragraph_range.clone()].chars().count();
+                    let paragraph_string: String = doc[paragraph_range.clone()].chars().collect();
+                    let markdown_without_links = replace_markdown_links(&paragraph_string);
+                    headers.first_paragraph_len =  markdown_without_links.len();
                     is_first_paragraph = false;
                 }
             },
@@ -946,6 +949,15 @@ fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize
     headers
 }
 
+fn replace_markdown_links(text: &str) -> String {
+    let re = Regex::new(r"\[([^\]]+)]\([^\)]+\)").unwrap();
+
+    re.replace_all(text, |caps: &regex::Captures<'_>| {
+        caps.get(1).map_or("", |m| m.as_str()).to_string()
+    })
+    .into_owned()
+}
+
 struct FindPanicUnwrap<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     is_const: bool,

tests/ui/too_long_first_doc_paragraph.rs

@@ -48,6 +48,11 @@ pub union Union2 {
 /// gravida non lacinia at, rhoncus eu lacus.
 fn f() {}
 
+/// Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc turpis nunc, lacinia
+/// a dolor in, pellentesque aliquet enim. Cras nec maximus sem.
+/// [this link](https://fooooooooooooooooooooooooooooooooooooooooooooooooooooooooo.com)
+pub fn foo() {}
+
 fn main() {
     // test code goes here
 }