auto-update-base.yaml

name: Auto-Update PR Base

on:
  push:
    branches:
      - main

jobs:
  auto-update-base:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v7
        with:
          script: |
            try {
              const { data: pulls } = await github.rest.pulls.list({
                owner: context.repo.owner,
                repo: context.repo.repo,
                state: "open",
              });

              for (const pull of pulls) {
                const hasAutoUpdateLabel = pull.labels.some(label => label.name === "auto-update-base");
                
                if (hasAutoUpdateLabel) {
                  try {
                    const pr = await github.rest.pulls.get({
                      owner: context.repo.owner,
                      repo: context.repo.repo,
                      pull_number: pull.number,
                    });

                    if (pr.data.mergeable_state === 'dirty') {
                      console.log(`[INFO] PR #${pull.number}: "${pull.title}" - Skipping update due to merge conflict.`);
                      continue;
                    }
                    if (pr.data.mergeable_state !== 'behind') {
                      console.log(`[INFO] PR #${pull.number}: "${pull.title}" - Base branch is up-to-date.`);
                      continue;
                    }

                    console.log(`[UPDATE] PR #${pull.number}: "${pull.title}" - Updating base branch...`);
                    try {
                      await github.rest.pulls.updateBranch({
                        owner: context.repo.owner,
                        repo: context.repo.repo,
                        pull_number: pull.number,
                      });
                      console.log(`[SUCCESS] PR #${pull.number}: "${pull.title}" - Base branch updated.`);
                    } catch (updateError) {
                      console.error(`[ERROR] PR #${pull.number}: Failed to update base branch - ${updateError.message}`);
                    }
                  } catch (diffError) {
                    console.error(`[ERROR] PR #${pull.number}: Failed to compare commits - ${diffError.message}`);
                  }
                }
              }
            } catch (error) {
              console.error(`[ERROR] Failed to list pull requests - ${error.message}`);
            }