performance-regression.yml

name: Performance Regression Check

concurrency:
  group: performance-regression-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: true

on:
  pull_request:
    paths:
      - 'src/**'
      - 'package.json'
      - 'pnpm-lock.yaml'
  push:
    branches:
      - main

permissions:
  contents: read

jobs:
  regression:
    if: github.event_name == 'pull_request' && contains(join(github.event.pull_request.labels.*.name, ','), 'test-regression')
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
      issues: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
        with:
          persist-credentials: false

      - name: Setup pnpm
        uses: pnpm/action-setup@a7487c7e89a18df4991f7f222e4898a00d66ddda # v4.1.0
        with:
          run_install: false

      - name: Setup Node.js
        uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
        with:
          node-version: '24'

      - name: Install dependencies
        run: pnpm install --frozen-lockfile

      - name: Build project
        run: pnpm build

      - name: Restore main baseline
        run: |
          git fetch origin main --depth=1
          git checkout origin/main -- bench/.baseline/performance-baseline.json || true

      - name: Check for regressions
        id: regression-check
        run: |
          if node bench/check-regression.js; then
            echo "regression_detected=false" >> $GITHUB_OUTPUT
          else
            echo "regression_detected=true" >> $GITHUB_OUTPUT
          fi

      - name: Upload regression report
        if: always()
        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
        with:
          name: regression-report
          path: bench/.results/regression-report.md
          if-no-files-found: ignore

      - name: Comment PR with results
        if: always() && github.event_name == 'pull_request' && github.event.pull_request.head.repo.fork == false
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
        with:
          script: |
            const fs = require('fs');
            const path = require('path');
            const reportPath = path.join(process.env.GITHUB_WORKSPACE, 'bench', '.results', 'regression-report.md');

            if (!fs.existsSync(reportPath)) {
              return;
            }

            const report = fs.readFileSync(reportPath, 'utf8');
            const body = `🤖 **Performance Check Results**

            ${report}`;

            const response = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
            });

            const comments = response.data;

            const botComment = comments.find(comment =>
              comment.user.type === 'Bot' &&
              comment.body.includes('Performance Check Results')
            );

            if (botComment) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body,
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body,
              });
            }

      - name: Fail if regression detected
        if: steps.regression-check.outputs.regression_detected == 'true'
        run: |
          echo "❌ Performance regression detected! See report above."
          exit 1

  update-baseline:
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    runs-on: ubuntu-latest
    permissions:
      contents: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
        with:
          fetch-depth: 0

      - name: Setup pnpm
        uses: pnpm/action-setup@a7487c7e89a18df4991f7f222e4898a00d66ddda # v4.1.0
        with:
          run_install: false

      - name: Setup Node.js
        uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
        with:
          node-version: '24'

      - name: Install dependencies
        run: pnpm install --frozen-lockfile

      - name: Build project
        run: pnpm build

      - name: Capture baseline
        run: node bench/capture-baseline.js

      - name: Commit baseline updates
        run: |
          git config --local user.email "action@github.com"
          git config --local user.name "GitHub Action"
          git add bench/.baseline/performance-baseline.json
          git diff --staged --quiet || git commit -m "chore: update performance baseline [skip ci]"
          git push || true