fix: pull request timeline missing last commit due to race in version data loading

Author: glehmann

src/browser/components/pr-review.tsx

@@ -763,12 +763,16 @@ function VersionBar() {
   const reviews = usePRReviewSelector((s) => s.reviews);
   const currentUser = usePRReviewSelector((s) => s.currentUser);
 
-  // Lazy-load version data on first mount (deferred from loadPRData)
+  // Lazy-load version data when commits are available (deferred from loadPRData).
+  // Deferring avoids a race: loadPRData populates commits asynchronously, and
+  // loadVersionData needs actual commits to group into versions. Without this
+  // guard, the mount-time effect fires before loadPRData finishes, leaving
+  // commits empty and the last commit's version never created.
   useEffect(() => {
-    if (!versionDataLoaded) {
+    if (!versionDataLoaded && commits.length > 0) {
       store.loadVersionData();
     }
-  }, [versionDataLoaded, store]);
+  }, [versionDataLoaded, store, commits]);
 
   // Map of SHA → whether it's a merge commit (for showing correct icon in dropdowns)
   const isMergeCommit = useMemo(() => {

src/browser/contexts/pr-review/index.tsx

@@ -3506,13 +3506,17 @@ export class PRReviewStore {
    *  the version/commit selector is first opened. */
   loadVersionData = async (): Promise<void> => {
     if (this.state.versionDataLoaded) return;
-    const { owner, repo, pr, commits } = this.state;
+    const { owner, repo, pr } = this.state;
 
     try {
       const pushVersionsData = await this.github
         .getPushVersions(owner, repo, pr.number)
         .catch(() => [] as PushVersion[]);
 
+      // Read commits from current state — loadPRData may have populated them
+      // while we waited for push versions (race on initial mount).
+      const commits = this.state.commits;
+
       // Merge force-push versions with commit-grouped versions
       const commitVersions = groupCommitsIntoVersions(commits, 2);
       const seenShas = new Set(pushVersionsData.map((v) => v.sha));