From ad7ba8375af7cfa549f7f70bc1e195655fb2a927 Mon Sep 17 00:00:00 2001
From: autonomic-bot <autonomic-bot@git.autonomic.zone>
Date: Tue, 2 Jun 2026 01:58:10 +0000
Subject: [PATCH] fix(recipe-upgrade): extend open upgrade PRs by
 commit-on-top, no force-push

Instead of force-pushing HEAD onto the existing PR branch (history rewrite),
add a commit ON TOP of the branch tip (fast-forward) when it already exists,
so the PR's history is preserved and it re-tests. Fresh branches still push
normally. The only remaining force-push is the mirror-main->upstream sync
(intentional mirroring), never a PR branch.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 .../skills/recipe-upgrade/open-recipe-pr.sh   | 28 +++++++++++++++----
 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/.claude/skills/recipe-upgrade/open-recipe-pr.sh b/.claude/skills/recipe-upgrade/open-recipe-pr.sh
index 397880a..88f365a 100755
--- a/.claude/skills/recipe-upgrade/open-recipe-pr.sh
+++ b/.claude/skills/recipe-upgrade/open-recipe-pr.sh
@@ -19,9 +19,11 @@
 #     never reflected it.
 #
 # Default mode (open a PR — preconditions: HEAD has the upgrade commit(s)):
-#   - If an open UPGRADE PR already exists for this recipe (branch 'upgrade-*'), the new work is
-#     pushed onto THAT PR's branch and the PR is updated + re-tested — ONE evolving upgrade PR per
-#     recipe, NOT a second parallel PR. Otherwise a fresh 'upgrade-<version>' branch + PR is opened.
+#   - If an open UPGRADE PR already exists for this recipe (branch 'upgrade-*'), the new work is added
+#     as a commit ON TOP of THAT PR's branch (a fast-forward — NO force-push) and the PR is updated +
+#     re-tested — ONE evolving upgrade PR per recipe, NOT a second parallel PR. Otherwise a fresh
+#     'upgrade-<version>' branch + PR is opened. (The only force-push here is the mirror-main sync
+#     above, which intentionally mirrors upstream main; PR branches are never force-pushed.)
 #   - Unrelated open PRs (e.g. a backup fix) are NEVER closed or touched — left for the operator.
 #   - Only PRs already merged into upstream main are closed (no-op merges) — see above.
 #
@@ -140,8 +142,24 @@ else
   BRANCH="upgrade-$(git rev-parse --short HEAD)"
 fi
 
-echo "→ Pushing branch '${BRANCH}'..."
-git push --force gitea "HEAD:refs/heads/${BRANCH}"
+# Land the work on the PR branch WITHOUT force-pushing. If the branch already exists (extend case, or
+# a stale same-named branch), add a commit ON TOP of its tip — a fast-forward, so the PR's history is
+# preserved and it re-tests. Otherwise push a fresh branch.
+if git rev-parse --verify --quiet "refs/remotes/gitea/${BRANCH}" >/dev/null; then
+  EXIST_TIP=$(git rev-parse "refs/remotes/gitea/${BRANCH}")
+  if [ "$(git rev-parse 'HEAD^{tree}')" = "$(git rev-parse "${EXIST_TIP}^{tree}")" ]; then
+    echo "→ '${BRANCH}' already has this exact tree — nothing new to push (will still re-test)."
+  else
+    ONTOP=$(GIT_AUTHOR_NAME="${GITEA_USERNAME}" GIT_AUTHOR_EMAIL="${GITEA_USERNAME}@git.autonomic.zone" \
+            GIT_COMMITTER_NAME="${GITEA_USERNAME}" GIT_COMMITTER_EMAIL="${GITEA_USERNAME}@git.autonomic.zone" \
+            git commit-tree "$(git rev-parse 'HEAD^{tree}')" -p "${EXIST_TIP}" -m "${LATEST_MSG}")
+    echo "→ Adding the new work on top of '${BRANCH}' (fast-forward, no force-push)..."
+    git push gitea "${ONTOP}:refs/heads/${BRANCH}"
+  fi
+else
+  echo "→ Pushing new branch '${BRANCH}'..."
+  git push gitea "HEAD:refs/heads/${BRANCH}"
+fi
 
 PR_BODY="${RECIPE_PR_BODY:-$(printf 'Recipe upgrade.\n\nCommits on top of upstream main:\n\n%s\n' "$(git log origin/main..HEAD --pretty='- %h %s')")}"
 PR_BODY="${PR_BODY}