coverage.yml

name: code coverage

on: 
  pull_request:
    branches:
    - main

jobs:
  comment-forge-coverage:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write

    steps:
    - name: Checkout code
      uses: actions/checkout@v3
      with:
        token: ${{ secrets.GITHUB_TOKEN }}

    - name: Install foundry
      uses: foundry-rs/foundry-toolchain@v1
      with:
          version: nightly
    - name: Run Forge build
      run: |
          forge --version
          forge build --sizes
      id: build
    - name: Run forge coverage
      id: coverage
      run: |
        {
        echo 'COVERAGE<<EOF'
        forge coverage | grep -v 'test/' | tail -n +6
        echo EOF
        } >> "$GITHUB_OUTPUT"
    
    - name: Check coverage is updated
      uses: actions/github-script@v5
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const fs = require('fs');
          const output = `${{ steps.coverage.outputs.COVERAGE }}`;
          const currentCoverageFile = fs.readFileSync("coverage.txt", "utf8");
          if (output != currentCoverageFile) {
            console.log(currentCoverageFile);
            core.setFailed('Code coverage not updated.');
          }

    - name: Comment on PR
      id: comment
      uses: actions/github-script@v5
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const output = `${{ steps.coverage.outputs.COVERAGE }}`;
          const commentBody = `Forge code coverage:\n${output}\n`;
          github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: commentBody
            });