From b063e0e656c32564d3a104cc4e36995a69da71c7 Mon Sep 17 00:00:00 2001
From: camc314 <18101008+camc314@users.noreply.github.com>
Date: Tue, 28 Oct 2025 15:42:39 +0000
Subject: [PATCH] feat(ast): add `is_inside_comment` method (#14907)

@Dunqing or @Boshen do you mind reviewing + merging please.
---
 crates/oxc_ast/src/lib.rs    |  2 +-
 crates/oxc_ast/src/trivia.rs | 46 ++++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/crates/oxc_ast/src/lib.rs b/crates/oxc_ast/src/lib.rs
index de94ca9376543..2f4b357b52dc1 100644
--- a/crates/oxc_ast/src/lib.rs
+++ b/crates/oxc_ast/src/lib.rs
@@ -78,7 +78,7 @@ pub use crate::{
     ast_builder_impl::{AstBuilder, NONE},
     ast_kind::{AstKind, AstType},
     ast_kind_impl::{MemberExpressionKind, ModuleDeclarationKind},
-    trivia::{CommentsRange, comments_range, has_comments_between},
+    trivia::{CommentsRange, comments_range, has_comments_between, is_inside_comment},
 };
 
 // After experimenting with two types of boxed enum variants:
diff --git a/crates/oxc_ast/src/trivia.rs b/crates/oxc_ast/src/trivia.rs
index 66016e6db0bba..37ab02f0a0c56 100644
--- a/crates/oxc_ast/src/trivia.rs
+++ b/crates/oxc_ast/src/trivia.rs
@@ -4,6 +4,7 @@
 //! including efficient range-based queries and iteration over comment collections.
 
 use std::{
+    cmp::Ordering,
     iter::FusedIterator,
     ops::{Bound, RangeBounds},
 };
@@ -57,6 +58,39 @@ pub fn has_comments_between(comments: &[Comment], span: Span) -> bool {
     comments_range(comments, span.start..span.end).count() > 0
 }
 
+/// Check if a position falls within any comment
+///
+/// Returns `true` if the specified position is inside any comment's span,
+/// including the start and end positions.
+///
+/// Uses binary search for efficient lookup in O(log n) time.
+///
+/// # Arguments
+///
+/// * `comments` - A slice of comments sorted by starting position
+/// * `pos` - The position to check
+///
+/// # Examples
+///
+/// ```ignore
+/// // Comment spans from position 10 to 20
+/// assert!(is_inside_comment(&comments, 15));  // Inside comment
+/// assert!(!is_inside_comment(&comments, 25)); // Outside comment
+/// ```
+pub fn is_inside_comment(comments: &[Comment], pos: u32) -> bool {
+    comments
+        .binary_search_by(|c| {
+            if pos < c.span.start {
+                Ordering::Greater
+            } else if pos > c.span.end {
+                Ordering::Less
+            } else {
+                Ordering::Equal
+            }
+        })
+        .is_ok()
+}
+
 /// Double-ended iterator over a range of comments, by starting position
 ///
 /// This iterator efficiently filters comments based on their starting positions,
@@ -162,4 +196,16 @@ mod test {
         assert_eq!(comments_range(&comments, ..18).count(), full_len.saturating_sub(1));
         assert_eq!(comments_range(&comments, ..=18).count(), full_len);
     }
+
+    #[test]
+    fn test_is_inside_comment() {
+        let comments =
+            vec![Comment::new(0, 4, CommentKind::Line), Comment::new(10, 20, CommentKind::Block)]
+                .into_boxed_slice();
+
+        assert!(is_inside_comment(&comments, 2));
+        assert!(!is_inside_comment(&comments, 5));
+        assert!(is_inside_comment(&comments, 15));
+        assert!(!is_inside_comment(&comments, 21));
+    }
 }