"#"

lib/sync.sh

@@ -170,7 +170,20 @@ reverse_sync() {
   log "INFO" "New human commits to sync:"
   echo "$human_commits" >&2
 
-  # 4. Push through josh to a staging branch
+  # 4. Merge subrepo changes onto the latest josh-filtered monorepo view
+  #    This ensures the staging branch is based on the latest monorepo main,
+  #    not on the common ancestor between subrepo and monorepo histories.
+  local subrepo_head
+  subrepo_head=$(git rev-parse HEAD)
+
+  git checkout -B sync-push "mono-filtered/${mono_branch}" >&2
+  git merge --no-ff "$subrepo_head" \
+    -m "Sync from subrepo $(date -u +%Y-%m-%dT%H:%M:%SZ)
+
+${BOT_TRAILER}: reverse/${subrepo_branch}/$(date -u +%Y-%m-%dT%H:%M:%SZ)" >&2 \
+    || die "Merge conflict during reverse sync — manual intervention needed"
+
+  # 5. Push merged branch through josh to a staging branch
   local ts
   ts=$(date +%Y%m%d-%H%M%S)
   local staging_branch="auto-sync/subrepo-${subrepo_branch}-${ts}"
@@ -178,7 +191,7 @@ reverse_sync() {
   if git push -o "base=${mono_branch}" "$(josh_auth_url)" "HEAD:refs/heads/${staging_branch}"; then
     log "INFO" "Pushed to staging branch via josh: ${staging_branch}"
 
-    # 5. Create PR on monorepo (NEVER direct push)
+    # 6. Create PR on monorepo (NEVER direct push)
     local pr_body
     pr_body="## Subrepo changes\n\nNew commits from subrepo \`${subrepo_branch}\`:\n\n\`\`\`\n${human_commits}\n\`\`\`\n\n**Review checklist:**\n- [ ] Changes scoped to synced subfolder\n- [ ] No leaked credentials or environment-specific config\n- [ ] CI passes"