fix(sync): paginate compare and resolve real head SHA

packages/backend/convex/githubClient.ts

@@ -117,6 +117,9 @@ const normalizeCompareCommit = (
   htmlUrl: commit.html_url,
 });
 
+const COMPARE_PER_PAGE = 100;
+const COMPARE_MAX_PAGES = 30; // bound: up to 3000 commits collected
+
 export const compareAcrossForkNetwork = async (
   octokit: Octokit,
   args: {
@@ -125,24 +128,46 @@ export const compareAcrossForkNetwork = async (
     baseOwner: string;
     baseBranch: string;
     headOwner: string;
+    headRepo: string;
     headBranch: string;
   },
 ): Promise<GitHubCompareSummary> => {
   const basehead = `${args.baseOwner}:${args.baseBranch}...${args.headOwner}:${args.headBranch}`;
-  const result = await octokit.rest.repos.compareCommitsWithBasehead({
+  const first = await octokit.rest.repos.compareCommitsWithBasehead({
     owner: args.owner,
     repo: args.repo,
     basehead,
-    per_page: 100,
+    per_page: COMPARE_PER_PAGE,
+    page: 1,
   });
-  const commits = result.data.commits.map(normalizeCompareCommit);
+  const rawCommits = [...first.data.commits];
+  const totalCommits = first.data.total_commits;
+  let page = 2;
+  while (rawCommits.length < totalCommits && page <= COMPARE_MAX_PAGES) {
+    const next = await octokit.rest.repos.compareCommitsWithBasehead({
+      owner: args.owner,
+      repo: args.repo,
+      basehead,
+      per_page: COMPARE_PER_PAGE,
+      page,
+    });
+    if (next.data.commits.length === 0) break;
+    rawCommits.push(...next.data.commits);
+    page += 1;
+  }
+  const head = await resolveBranchHead(
+    octokit,
+    args.headOwner,
+    args.headRepo,
+    args.headBranch,
+  );
   return {
-    aheadBy: result.data.ahead_by,
-    mergeBaseSha: result.data.merge_base_commit.sha,
-    headSha: commits[commits.length - 1]?.sha,
-    baseSha: result.data.base_commit.sha,
-    htmlUrl: result.data.html_url,
-    commits,
+    aheadBy: first.data.ahead_by,
+    mergeBaseSha: first.data.merge_base_commit.sha,
+    headSha: head.sha,
+    baseSha: first.data.base_commit.sha,
+    htmlUrl: first.data.html_url,
+    commits: rawCommits.map(normalizeCompareCommit),
   };
 };
 

packages/backend/convex/githubSync.ts

@@ -32,8 +32,13 @@ const toStatus = (upstreamAheadBy: number, forkAheadBy: number) => {
   return 'unknown' as const;
 };
 
-const getLastCommitAt = (compare: GitHubCompareSummary) =>
-  compare.commits[compare.commits.length - 1]?.committedAt;
+const getLastCommitAt = (compare: GitHubCompareSummary) => {
+  const head = compare.commits.find((c) => c.sha === compare.headSha);
+  return (
+    head?.committedAt ??
+    compare.commits[compare.commits.length - 1]?.committedAt
+  );
+};
 
 const ensureForkMetadata = (spoon: Doc<'spoons'>) => {
   if (!spoon.forkOwner || !spoon.forkRepo) {
@@ -121,6 +126,7 @@ const refreshOwnedSpoon = async (
         baseOwner: forkOwner,
         baseBranch: resolvedForkBranch,
         headOwner: spoon.upstreamOwner,
+        headRepo: spoon.upstreamRepo,
         headBranch: upstreamBranch,
       }),
       compareAcrossForkNetwork(octokit, {
@@ -129,6 +135,7 @@ const refreshOwnedSpoon = async (
         baseOwner: spoon.upstreamOwner,
         baseBranch: upstreamBranch,
         headOwner: forkOwner,
+        headRepo: forkRepo,
         headBranch: resolvedForkBranch,
       }),
       listPullRequests(octokit, { owner: forkOwner, repo: forkRepo }),