fix: avoid merging unrelated comments into replies

src/gitea/dto.rs

@@ -46,6 +46,8 @@ pub struct ReviewCommentDto {
     pub path: Option<String>,
     pub line: Option<i64>,
     pub pull_request_review_id: Option<i64>,
+    #[serde(default, alias = "in_reply_to", alias = "in_reply_to_id", alias = "reply_to")]
+    pub in_reply_to: Option<i64>,
     pub original_position: Option<u64>,
     pub position: Option<u64>,
     pub commit_id: Option<String>,

src/normalize.rs

@@ -48,59 +48,53 @@ pub fn normalize_bundle(repo: &str, bundle: PullBundleDto) -> PrReviewDocument {
 }
 
 fn normalize_threads(comments: Vec<ReviewCommentDto>) -> Vec<CommentThread> {
-    let mut grouped: BTreeMap<String, Vec<ReviewCommentDto>> = BTreeMap::new();
+    let mut all = comments;
+    all.sort_by_key(comment_sort_key);
 
-    for comment in comments {
+    let comment_ids: std::collections::BTreeSet<i64> = all.iter().map(|comment| comment.id).collect();
-        let key = thread_key(&comment);
+    let mut roots: Vec<ReviewCommentDto> = Vec::new();
-        grouped.entry(key).or_default().push(comment);
+    let mut children: BTreeMap<i64, Vec<ReviewCommentDto>> = BTreeMap::new();
+
+    for comment in all {
+        if let Some(parent_id) = comment.in_reply_to
+            && comment_ids.contains(&parent_id)
+        {
+            children.entry(parent_id).or_default().push(comment);
+            continue;
+        }
+        roots.push(comment);
     }
 
-    grouped
+    roots
         .into_iter()
-        .map(|(thread_id, mut group)| {
+        .map(|root| {
-            group.sort_by_key(comment_sort_key);
+            let mut replies = Vec::new();
-
+            collect_replies(root.id, &mut children, &mut replies);
-            let root = group.remove(0);
-            let file_path = root
-                .path
-                .clone()
-                .or_else(|| group.iter().find_map(|comment| comment.path.clone()));
-            let line = root
-                .line
-                .or_else(|| group.iter().find_map(|comment| comment.line));
-
             CommentThread {
-                thread_id,
+                thread_id: format!("comment-{}", root.id),
-                file_path,
+                file_path: root.path.clone(),
-                line,
+                line: root.line,
                 root_comment: to_comment_item(root),
-                replies: group.into_iter().map(to_comment_item).collect(),
+                replies: replies.into_iter().map(to_comment_item).collect(),
             }
         })
         .collect()
 }
 
-fn thread_key(comment: &ReviewCommentDto) -> String {
+fn collect_replies(
-    match comment.pull_request_review_id {
+    parent_id: i64,
-        Some(review_id) => format!(
+    children: &mut BTreeMap<i64, Vec<ReviewCommentDto>>,
-            "review-{review_id}-{path}-{line}-{position}-{commit}",
+    out: &mut Vec<ReviewCommentDto>,
-            path = comment.path.as_deref().unwrap_or(""),
+) {
-            line = comment
+    let Some(mut direct_replies) = children.remove(&parent_id) else {
-                .line
+        return;
-                .map(|value| value.to_string())
+    };
-                .unwrap_or_default(),
+    direct_replies.sort_by_key(comment_sort_key);
-            position = comment
+
-                .original_position
+    for reply in direct_replies {
-                .or(comment.position)
+        let reply_id = reply.id;
-                .map(|value| value.to_string())
+        out.push(reply);
-                .unwrap_or_default(),
+        collect_replies(reply_id, children, out);
-            commit = comment
-                .original_commit_id
-                .as_deref()
-                .or(comment.commit_id.as_deref())
-                .unwrap_or("")
-        ),
-        None => format!("comment-{}", comment.id),
     }
 }
 

tests/normalize_tests.rs

@@ -55,6 +55,7 @@ fn normalize_groups_replies_and_sorts_threads_by_time() {
                 path: Some("src/main.rs".into()),
                 line: Some(10),
                 pull_request_review_id: Some(7),
+                in_reply_to: Some(1),
                 original_position: Some(10),
                 position: Some(10),
                 commit_id: Some("abc123".into()),
@@ -72,6 +73,7 @@ fn normalize_groups_replies_and_sorts_threads_by_time() {
                 path: Some("src/main.rs".into()),
                 line: Some(10),
                 pull_request_review_id: Some(7),
+                in_reply_to: None,
                 original_position: Some(10),
                 position: Some(10),
                 commit_id: Some("abc123".into()),
@@ -89,6 +91,7 @@ fn normalize_groups_replies_and_sorts_threads_by_time() {
                 path: Some("src/lib.rs".into()),
                 line: Some(22),
                 pull_request_review_id: Some(8),
+                in_reply_to: None,
                 original_position: Some(22),
                 position: Some(22),
                 commit_id: Some("def456".into()),
@@ -170,3 +173,79 @@ fn normalize_groups_replies_and_sorts_threads_by_time() {
     assert_eq!(doc.threads[1].file_path.as_deref(), Some("src/main.rs"));
     assert_eq!(doc.threads[1].line, Some(10));
 }
+
+#[test]
+fn normalize_does_not_merge_unrelated_comments_on_same_file() {
+    let bundle = PullBundleDto {
+        pull: PullDto {
+            number: 100,
+            title: "T".into(),
+            state: "open".into(),
+            body: None,
+            user: UserDto {
+                login: "alice".into(),
+            },
+            base: PullBranchDto {
+                ref_name: "main".into(),
+            },
+            head: PullBranchDto {
+                ref_name: "feature/y".into(),
+            },
+            created_at: "2026-04-08T10:00:00Z".into(),
+            updated_at: "2026-04-08T10:00:00Z".into(),
+            merged_at: None,
+            additions: None,
+            deletions: None,
+            changed_files: None,
+        },
+        reviews: vec![],
+        comments: vec![
+            ReviewCommentDto {
+                id: 10,
+                body: "first line comment".into(),
+                created_at: "2026-04-08T12:01:00Z".into(),
+                updated_at: None,
+                user: UserDto {
+                    login: "bob".into(),
+                },
+                path: Some("src/main.rs".into()),
+                line: Some(10),
+                pull_request_review_id: Some(1),
+                in_reply_to: None,
+                original_position: Some(10),
+                position: Some(10),
+                commit_id: Some("abc123".into()),
+                original_commit_id: Some("abc123".into()),
+                diff_hunk: None,
+            },
+            ReviewCommentDto {
+                id: 11,
+                body: "second line comment".into(),
+                created_at: "2026-04-08T12:02:00Z".into(),
+                updated_at: None,
+                user: UserDto {
+                    login: "bob".into(),
+                },
+                path: Some("src/main.rs".into()),
+                line: Some(20),
+                pull_request_review_id: Some(1),
+                in_reply_to: None,
+                original_position: Some(20),
+                position: Some(20),
+                commit_id: Some("abc123".into()),
+                original_commit_id: Some("abc123".into()),
+                diff_hunk: None,
+            },
+        ],
+        commits: vec![],
+        files: vec![],
+    };
+
+    let doc = normalize_bundle("org/repo", bundle);
+
+    assert_eq!(doc.threads.len(), 2);
+    assert_eq!(doc.threads[0].root_comment.id, 10);
+    assert_eq!(doc.threads[0].replies.len(), 0);
+    assert_eq!(doc.threads[1].root_comment.id, 11);
+    assert_eq!(doc.threads[1].replies.len(), 0);
+}