add fn comment

crates/ast/src/token.rs

@@ -528,6 +528,17 @@ impl Token {
         }
     }
 
+    /// Returns the comment if the kind is [`TokenKind::Comment`], and whether it's a doc-comment.
+    #[inline]
+    pub const fn comment(&self) -> Option<(bool, DocComment)> {
+        match self.kind {
+            TokenKind::Comment(is_doc, kind, symbol) => {
+                Some((is_doc, DocComment { span: self.span, kind, symbol }))
+            }
+            _ => None,
+        }
+    }
+
     /// Returns the comment if the kind is [`TokenKind::Comment`].
     ///
     /// Does not check that `is_doc` is `true`.

crates/parse/src/parser/mod.rs

@@ -741,11 +741,11 @@ impl<'sess, 'ast> Parser<'sess, 'ast> {
 
         debug_assert!(next.is_comment_or_doc());
         self.prev_token = std::mem::replace(&mut self.token, next);
-        while let Some(doc) = self.token.doc() {
-            if !self.token.is_comment() {
+        while let Some((is_doc, doc)) = self.token.comment() {
+            if is_doc {
                 self.docs.push(doc);
             }
-            // Don't set `previon_token` on purpose.
+            // Don't set `prev_token` on purpose.
             self.token = self.next_token();
         }