Set the limit of characters to 200 and don't run the lint on private items unless config allows it

clippy_lints/src/doc/mod.rs

@@ -493,7 +493,13 @@ impl<'tcx> LateLintPass<'tcx> for Documentation {
 
         match cx.tcx.hir_node(cx.last_node_with_lint_attrs) {
             Node::Item(item) => {
-                too_long_first_doc_paragraph::check(cx, attrs, item.kind, headers.first_paragraph_len);
+                too_long_first_doc_paragraph::check(
+                    cx,
+                    item,
+                    attrs,
+                    headers.first_paragraph_len,
+                    self.check_private_items,
+                );
                 match item.kind {
                     ItemKind::Fn(sig, _, body_id) => {
                         if !(is_entrypoint_fn(cx, item.owner_id.to_def_id())
@@ -627,9 +633,8 @@ fn check_attrs(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &[
         acc
     });
     doc.pop();
-    let doc = doc.trim();
 
-    if doc.is_empty() {
+    if doc.trim().is_empty() {
         if let Some(span) = span_of_fragments(&fragments) {
             span_lint_and_help(
                 cx,
@@ -653,7 +658,7 @@ fn check_attrs(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &[
         cx,
         valid_idents,
         parser.into_offset_iter(),
-        doc,
+        &doc,
         Fragments {
             fragments: &fragments,
             doc: &doc,

clippy_lints/src/doc/too_long_first_doc_paragraph.rs

@@ -1,6 +1,6 @@
 use rustc_ast::ast::Attribute;
 use rustc_errors::Applicability;
-use rustc_hir::ItemKind;
+use rustc_hir::{Item, ItemKind};
 use rustc_lint::LateContext;
 
 use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
@@ -10,13 +10,17 @@ use super::TOO_LONG_FIRST_DOC_PARAGRAPH;
 
 pub(super) fn check(
     cx: &LateContext<'_>,
+    item: &Item<'_>,
     attrs: &[Attribute],
-    item_kind: ItemKind<'_>,
     mut first_paragraph_len: usize,
+    check_private_items: bool,
 ) {
-    if first_paragraph_len <= 100
+    if !check_private_items && !cx.effective_visibilities.is_exported(item.owner_id.def_id) {
+        return;
+    }
+    if first_paragraph_len <= 200
         || !matches!(
-            item_kind,
+            item.kind,
             ItemKind::Static(..)
                 | ItemKind::Const(..)
                 | ItemKind::Fn(..)
@@ -32,6 +36,7 @@ pub(super) fn check(
     {
         return;
     }
+
     let mut spans = Vec::new();
     let mut should_suggest_empty_doc = false;
 
@@ -42,7 +47,7 @@ pub(super) fn check(
             let doc = doc.trim();
             if spans.len() == 1 {
                 // We make this suggestion only if the first doc line ends with a punctuation
-                // because if might just need to add an empty line with `///`.
+                // because it might just need to add an empty line with `///`.
                 should_suggest_empty_doc = doc.ends_with('.') || doc.ends_with('!') || doc.ends_with('?');
             }
             let len = doc.chars().count();
@@ -68,7 +73,7 @@ pub(super) fn check(
             |diag| {
                 diag.span_suggestion(
                     new_span,
-                    "add",
+                    "add an empty line",
                     format!("{snippet}///\n"),
                     Applicability::MachineApplicable,
                 );

tests/ui/too_long_first_doc_paragraph-fix.fixed

@@ -4,5 +4,6 @@
 ///
 /// A much longer explanation that goes into a lot more detail about
 /// how the thing works, possibly with doclinks and so one,
-/// and probably spanning a many rows.
-struct Foo;
+/// and probably spanning a many rows. Blablabla, it needs to be over
+/// 200 characters so I needed to write something longeeeeeeer.
+pub struct Foo;

tests/ui/too_long_first_doc_paragraph-fix.rs

@@ -3,5 +3,6 @@
 /// A very short summary.
 /// A much longer explanation that goes into a lot more detail about
 /// how the thing works, possibly with doclinks and so one,
-/// and probably spanning a many rows.
-struct Foo;
+/// and probably spanning a many rows. Blablabla, it needs to be over
+/// 200 characters so I needed to write something longeeeeeeer.
+pub struct Foo;

tests/ui/too_long_first_doc_paragraph-fix.stderr

@@ -4,7 +4,8 @@ error: first doc comment paragraph is too long
 LL | / /// A very short summary.
 LL | | /// A much longer explanation that goes into a lot more detail about
 LL | | /// how the thing works, possibly with doclinks and so one,
-LL | | /// and probably spanning a many rows.
+LL | | /// and probably spanning a many rows. Blablabla, it needs to be over
+LL | | /// 200 characters so I needed to write something longeeeeeeer.
    | |_
    |
    = note: `-D clippy::too-long-first-doc-paragraph` implied by `-D warnings`

tests/ui/too_long_first_doc_paragraph.rs

@@ -19,7 +19,7 @@ impl Bar {}
 /// Nunc turpis nunc, lacinia
 /// a dolor in, pellentesque aliquet enim. Cras nec maximus sem. Mauris arcu libero,
 /// gravida non lacinia at, rhoncus eu lacus.
-enum Enum {
+pub enum Enum {
     A,
 }
 
@@ -27,7 +27,7 @@ enum Enum {
 /// ipsum dolor sit amet, consectetur adipiscing elit. Nunc turpis nunc, lacinia
 /// a dolor in, pellentesque aliquet enim. Cras nec maximus sem. Mauris arcu libero,
 /// gravida non lacinia at, rhoncus eu lacus.
-union Union {
+pub union Union {
     a: u8,
     b: u8,
 }
@@ -37,11 +37,17 @@ union Union {
 /// Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc turpis nunc, lacinia
 /// a dolor in, pellentesque aliquet enim. Cras nec maximus sem. Mauris arcu libero,
 /// gravida non lacinia at, rhoncus eu lacus.
-union Union2 {
+pub union Union2 {
     a: u8,
     b: u8,
 }
 
+// Should not warn! (not public)
+/// Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc turpis nunc, lacinia
+/// a dolor in, pellentesque aliquet enim. Cras nec maximus sem. Mauris arcu libero,
+/// gravida non lacinia at, rhoncus eu lacus.
+fn f() {}
+
 fn main() {
     // test code goes here
 }