PR Test Coverage

A Github Action to report the test coverage of changed files in a pull request. All it needs is an lcov.info file. It provides a summary of the coverage for all files and changed files separately, and a detailed table with coverage metrics per changed file.

Features

• 📊 Generates comprehensive coverage reports from LCOV files
• 💬 Posts coverage summaries as PR comments
• 🔄 Updates existing comments or creates new ones
• 📈 Shows coverage for all files and changed files separately
• 📋 Detailed table with coverage metrics per changed file
• ⚠️ Configurable coverage thresholds with action failure
• 📦 Optional artifact upload for coverage reports
• 🎯 Supports custom working directories

Usage

Basic Usage

name: Test Coverage
on:
  pull_request:
    branches: [ main ]

jobs:
  coverage:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
    
    steps:
      - uses: actions/checkout@v4
      
      - name: Run tests and generate coverage
        run: |
          # Your test commands here that generate LCOV report
          npm test -- --coverage
      
      - name: PR Test Coverage
        uses: jbaczuk/pr-test-coverage@v1
        with:
          lcov-file: coverage/lcov.info
          github-token: ${{ secrets.GITHUB_TOKEN }}

Advanced Usage

- name: PR Test Coverage
  uses: jbaczuk/pr-test-coverage@v1
  with:
    # Required: Path to LCOV file
    lcov-file: coverage/lcov.info
    
    # Required: GitHub token for API access
    github-token: ${{ secrets.GITHUB_TOKEN }}
    
    # Optional: Working directory (default: repository root)
    working-directory: ./my-app
    
    # Optional: Minimum coverage for all files (default: 0)
    all-files-minimum-coverage: 80
    
    # Optional: Minimum coverage for changed files (default: 0)
    changed-files-minimum-coverage: 90
    
    # Optional: Upload coverage as artifact (default: empty/disabled)
    artifact-name: coverage-report
    
    # Optional: Update existing comment vs create new (default: true)
    update-comment: true

Inputs

Input	Description	Required	Default
lcov-file	Path to the LCOV file (e.g., coverage/lcov.info)	✅	-
github-token	GitHub token for API access and posting comments	✅	${{ github.token }}
working-directory	Working directory to run the action from	❌	'' (repository root)
all-files-minimum-coverage	Minimum coverage percentage for all files (0-100)	❌	0
changed-files-minimum-coverage	Minimum coverage percentage for changed files (0-100)	❌	0
artifact-name	Name for coverage artifact upload (empty to skip)	❌	''
update-comment	Whether to update existing comment or create new one	❌	true

Required Permissions

The action requires the following permissions in your workflow:

permissions:
  contents: read        # To access repository files
  pull-requests: write  # To post and update PR comments

Example Output

The action will post a comment on your pull request that looks like this:

Coverage Report ⚠️

All Files

• Lines: 847/1205 (70.3%) ⚠️
• Functions: 156/198 (78.8%)
• Branches: 234/298 (78.5%)

Changed Files

• Lines: 142/165 (86.1%) ✅
• Functions: 28/32 (87.5%)
• Branches: 45/52 (86.5%)

Files changed:

File	Lines	Line %	Functions	Function %	Branches	Branch %
📁 src	142/165	86.1%	28/32	87.5%	45/52	86.5%
📁 components	69/80	86.3%	12/14	85.7%	20/25	80.0%
📁 Button	24/28	85.7%	4/5	80.0%	8/10	80.0%
📄 Button.tsx	24/28	85.7%	4/5	80.0%	8/10	80.0%
📁 Modal	45/52	86.5%	8/9	88.9%	12/15	80.0%
📄 Modal.tsx	45/52	86.5%	8/9	88.9%	12/15	80.0%
📁 hooks	32/35	91.4%	6/7	85.7%	10/12	83.3%
📄 useAuth.ts	32/35	91.4%	6/7	85.7%	10/12	83.3%
📁 services	28/32	87.5%	7/8	87.5%	11/13	84.6%
📁 api	28/32	87.5%	7/8	87.5%	11/13	84.6%
📄 userService.ts	28/32	87.5%	7/8	87.5%	11/13	84.6%
📁 utils	13/18	72.2%	3/3	100.0%	4/2	66.7%
📄 validation.ts	13/18	72.2%	3/3	100.0%	4/2	66.7%

Coverage Status Icons

The action uses visual indicators to quickly show coverage status:

• ✅ Good coverage (≥80%)
• ⚠️ Moderate coverage (60-79%)
• ❌ Low coverage (<60%)

Failure Conditions

The action will fail if:

1. LCOV file not found - The specified LCOV file doesn't exist
2. Not a pull request - The action is not running in a PR context
3. Coverage below threshold - When coverage falls below specified minimums:
   • All files coverage below all-files-minimum-coverage
   • Changed files coverage below changed-files-minimum-coverage

Supported LCOV Format

The action supports standard LCOV format with the following metrics:

• Lines: LF (lines found) and LH (lines hit)
• Functions: FNF (functions found) and FNH (functions hit)
• Branches: BRF (branches found) and BRH (branches hit)

Common Integration Examples

Node.js with Jest

- name: Install dependencies
  run: npm ci

- name: Run tests with coverage
  run: npm test -- --coverage --coverageReporters=lcov

- name: PR Test Coverage
  uses: jbaczuk/pr-test-coverage@v1
  with:
    lcov-file: coverage/lcov.info
    github-token: ${{ secrets.GITHUB_TOKEN }}

Python with pytest-cov

- name: Install dependencies
  run: |
    pip install pytest pytest-cov

- name: Run tests with coverage
  run: pytest --cov=. --cov-report=lcov

- name: PR Test Coverage
  uses: jbaczuk/pr-test-coverage@v1
  with:
    lcov-file: coverage.lcov
    github-token: ${{ secrets.GITHUB_TOKEN }}

Go with go-test-coverage

- name: Run tests with coverage
  run: |
    go test -coverprofile=coverage.out ./...
    go tool cover -func=coverage.out -o=coverage.lcov

- name: PR Test Coverage
  uses: jbaczuk/pr-test-coverage@v1
  with:
    lcov-file: coverage.lcov
    github-token: ${{ secrets.GITHUB_TOKEN }}

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.