update-pr-metadata.yml

name: Update Metadata

on:
  # CAREFUL! https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
  pull_request_target:
    types: [opened, edited, synchronize, reopened]

concurrency: 
  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
  cancel-in-progress: true

jobs:
  update-metadata:
    runs-on: ubuntu-latest

    steps:
      - name: Add labels
        uses: silverhand-io/actions-add-labels-run-steps@v1.2.1
        with:
          title: ${{ github.event.pull_request.title || github.event.issue.title }}
          github-token: ${{ github.token }}

      - name: Add assignees
        if: |
          contains(fromJson('["opened", "reopened"]'), github.event.action) &&
          !endsWith(github.event.pull_request.user.login, '[bot]')
        uses: actions-ecosystem/action-add-assignees@v1
        with:
          github_token: ${{ github.token }}
          assignees: ${{ github.event.pull_request.user.login }}

  pr-size-diff:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4
        with:
          # https://github.com/actions/checkout/issues/518#issuecomment-890401887
          ref: refs/pull/${{ github.event.number }}/merge
          fetch-depth: 0
          persist-credentials: false

      - name: Prepare
        run: |
          git checkout master
          git checkout -
          curl -fsSLO https://gist.githubusercontent.com/gao-sun/88dac6c38e86f4ae12c8a7c3e777040a/raw/07276574142455b3dfeace5d7f4a370447a112b3/git-file-size-diff.sh
          chmod +x git-file-size-diff.sh

      - uses: actions/github-script@v7
        id: message
        with:
          result-encoding: string
          script: |
            const child_process = require('child_process');
            const result = child_process
              .execSync('./git-file-size-diff.sh --cached master', { encoding: 'utf-8' })
              .split('\n');
            const diff = Number(result.pop());

            // https://stackoverflow.com/a/18650828/12514940
            function formatBytes(bytes, decimals = 2) {
              if (bytes === 0) return '0 Bytes';

              const k = 1024;
              const dm = decimals < 0 ? 0 : decimals;
              const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];

              const i = Math.floor(Math.log(bytes) / Math.log(k));

              return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
            }

            function getPrefix(bytes) {
              if (bytes === 0) {
                return '';
              }

              return diff > 0 ? ':chart_with_upwards_trend: +' : ':chart_with_downwards_trend: -';
            }

            function format(bytes) {
              return `${
                bytes > 1024 * 10 ? ':warning: ' : ''
              }${
                getPrefix(bytes)
              }${formatBytes(Math.abs(bytes))}`;
            }

            const filesHeader = `|Name|Diff|\n|---|---|\n`;
            const filesData = result.map((row) => {
              const [diff, filename] = row.split('\t');
              return `|${filename}|${format(Number(diff))}|`;
            }).join('\n');

            return `#### COMPARE TO \`master\`\n**Total Size Diff** ${format(diff)}\n${
              result.length ? `\n<details>\n<summary><b>Diff by File</b></summary>\n\n${filesHeader}${filesData}</details>\n` : ''
            }`;
      
      - uses: marocchino/sticky-pull-request-comment@v2
        with:
          message: |
            ${{ steps.message.outputs.result }}