Add cherry pick CI workflow

.github/workflows/cherry-pick-to-celestia.yml

@@ -0,0 +1,64 @@
+name: Cherry-pick commits and open PR
+
+on:
+  pull_request:
+    branches:
+      - integration
+    types:
+      - closed
+  workflow_dispatch:
+    inputs:
+      mode:
+        description: "Choose operation mode: 'reset' to start fresh, 'continue' to resume from existing branch"
+        required: true
+        default: "continue"
+
+jobs:
+  cherry-pick-and-create-pr:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+
+    - name: Set up Git
+      run: |
+        git config user.name "github-actions[bot]"
+        git config user.email "github-actions[bot]@users.noreply.github.com"
+
+    - name: Fetch all branches
+      run: git fetch --all
+
+    - name: Check if PR already exists
+      id: check-pr
+      uses: actions/github-script@v6
+      with:
+        script: |
+          const { data: pulls } = await github.pulls.list({
+            owner: context.repo.owner,
+            repo: context.repo.repo,
+            head: `${context.repo.owner}:cherry-pick-integration-celestia`
+          });
+          if (pulls.length > 0) {
+            core.setOutput('pr_exists', 'true');
+            core.setOutput('pr_url', pulls[0].html_url);
+          } else {
+            core.setOutput('pr_exists', 'false');
+          }
+
+    - name: Run Cherry-pick Script in reset mode
+      if: github.event_name == 'pull_request' && github.event.pull_request.merged == true && steps.check-pr.outputs.pr_exists == 'false'
+      run: |
+        ./scripts/cherry-pick-integration.sh reset
+
+    - name: Run Cherry-pick Script in continue mode
+      if: github.event_name == 'workflow_dispatch' || (github.event_name == 'pull_request' && steps.check-pr.outputs.pr_exists == 'false')
+      run: |
+        ./scripts/cherry-pick-integration.sh continue
+
+    - name: Log existing PR
+      if: steps.check-pr.outputs.pr_exists == 'true'
+      run: |
+        echo "A PR already exists: ${{ steps.check-pr.outputs.pr_url }}. No new PR will be created."

scripts/cherry-pick-to-celestia.sh

@@ -0,0 +1,124 @@
+#!/usr/bin/env bash
+
+# A script to automate the cherry-picking of commits from the "integration" branch
+# into the "celestia-integration" branch with support for conflict resolution.
+#
+# USAGE:
+#   ./cherry-pick-integration.sh [MODE]
+#
+# PARAMETERS:
+#   MODE:
+#     - reset:
+#         - Deletes the existing "cherry-pick-integration-celestia" branch (if it exists).
+#         - Recreates the branch from the "celestia-integration" branch.
+#         - Starts cherry-picking commits from the "integration" branch from the beginning.
+#     - continue:
+#         - Resumes from the current state of the "cherry-pick-integration-celestia" branch.
+#         - Skips commits that have already been cherry-picked or resolved.
+#         - Continues with unprocessed commits.
+#
+# PROCESS:
+#   1. Fetches the latest updates from the remote repository for both branches.
+#   2. Depending on the MODE:
+#       - In "reset" mode:
+#         - Deletes and recreates the branch "cherry-pick-integration-celestia".
+#       - In "continue" mode:
+#         - Uses the existing "cherry-pick-integration-celestia" branch or creates it if missing.
+#   3. Cherry-picks all new commits from the "integration" branch to the target branch:
+#       - Skips already cherry-picked commits by checking commit logs.
+#       - Pushes unresolved conflicts to the branch for manual resolution.
+#       - If no conflicts occur, pushes the updated branch automatically.
+#   4. Exits with a non-zero status if conflicts are encountered.
+#
+# ERROR HANDLING:
+#   - If a conflict occurs during cherry-pick, the script:
+#       - Aborts the current cherry-pick operation.
+#       - Stages the conflict state and pushes it to the branch for manual resolution.
+#       - Exits with an error message instructing the user to resolve the conflicts.
+#
+# EXAMPLES:
+#   1. Start fresh and reapply all commits:
+#      ./cherry-pick-to-celestia.sh reset
+#
+#   2. Continue cherry-picking from where it left off:
+#      ./cherry-pick-to-celestia.sh continue
+#
+
+set -e
+
+MODE=$1
+BRANCH_NAME="cherry-pick-integration-celestia"
+INTEGRATION_BRANCH="integration"
+TARGET_BRANCH="celestia-integration"
+
+function is_commit_processed() {
+  local commit=$1
+  local marker="Cherry-picked from commit $commit"
+  git log $BRANCH_NAME --grep="$marker" -q
+}
+
+function init_branch() {
+  if [ "$MODE" == "reset" ]; then
+    echo "Reset mode: Re-creating branch $BRANCH_NAME from $TARGET_BRANCH"
+    git branch -D $BRANCH_NAME || echo "Branch $BRANCH_NAME does not exist locally. Skipping deletion."
+    git checkout origin/$TARGET_BRANCH
+    git checkout -B $BRANCH_NAME
+    git push --set-upstream origin $BRANCH_NAME
+  elif [ "$MODE" == "continue" ]; then
+    echo "Continue mode: Reusing existing branch $BRANCH_NAME"
+    git checkout $BRANCH_NAME || {
+      echo "Branch $BRANCH_NAME does not exist locally. Creating from $TARGET_BRANCH."
+      git checkout origin/$TARGET_BRANCH
+      git checkout -B $BRANCH_NAME
+    }
+  else
+    echo "Invalid mode. Use 'reset' or 'continue'."
+    exit 1
+  fi
+}
+
+function cherry_pick_commits() {
+  echo "Fetching latest commits from $INTEGRATION_BRANCH and $TARGET_BRANCH"
+  git fetch origin $INTEGRATION_BRANCH $TARGET_BRANCH
+
+  local last_merged_commit=$(git log -1 --pretty=format:"%H" origin/$INTEGRATION_BRANCH)
+  local pr_commits=$(git log origin/$TARGET_BRANCH..$last_merged_commit --pretty=format:"%H" --)
+
+  echo "Cherry-picking commits from $INTEGRATION_BRANCH to $BRANCH_NAME"
+  for commit in $pr_commits; do
+    if is_commit_processed $commit; then
+      echo "Commit $commit already processed. Skipping."
+      continue
+    fi
+
+    echo "Cherry-picking commit $commit"
+    if ! git cherry-pick $commit; then
+      echo "Conflict detected during cherry-pick of $commit."
+      git status
+      git cherry-pick --abort
+
+      echo "Saving conflict state for manual resolution."
+      git add .
+      git commit -m "WIP: Resolve conflicts from cherry-pick of $commit (Cherry-picked from commit $commit)" || echo "No changes to commit."
+      git push --force origin $BRANCH_NAME
+
+      echo "Conflicts pushed to branch $BRANCH_NAME. Exiting for manual resolution."
+      echo "Don't reset any commit and please resolve conflicts directly. Use \`git commit --amend --no-edit\` after resolving"
+      exit 1
+    fi
+
+    git commit --amend -m "$(git log -1 --pretty=%B)$'\n\n'Cherry-picked from commit $commit"
+  done
+
+  git push --force origin $BRANCH_NAME
+}
+
+function main() {
+  echo "Running Cherry-pick Script with MODE=$MODE"
+  init_branch
+  cherry_pick_commits
+  echo "Cherry-pick completed successfully."
+}
+
+main
+