What is TestLink?

TestLink is a PHP library that creates coverage links between your tests and production code. It works with both Pest and PHPUnit, helping you track which tests cover which methods and ensuring your test suite stays aligned with your codebase.

The Problem

As codebases grow, maintaining the relationship between tests and production code becomes challenging:

• Which tests cover this method? When modifying production code, you need to know which tests to run.
• Is this test still relevant? When a method is refactored or removed, how do you find the associated tests?
• Are all methods tested? How do you ensure critical methods have corresponding tests?

The Solution

TestLink provides a simple mechanism for linking tests to production code:

Pest

test('processes valid payments', function () {
    $result = app(PaymentService::class)->process($validPayment);

    expect($result->success)->toBeTrue();
})->linksAndCovers(PaymentService::class.'::process');

PHPUnit

use TestFlowLabs\TestingAttributes\LinksAndCovers;

class PaymentServiceTest extends TestCase
{
    #[LinksAndCovers(PaymentService::class, 'process')]
    public function test_processes_valid_payments(): void
    {
        $result = app(PaymentService::class)->process($this->validPayment);

        $this->assertTrue($result->success);
    }
}

Key Features

Coverage Reports

Generate reports showing test coverage relationships:

testlink report          # Console output
testlink report --json   # JSON output for CI/CD

Validation

Verify that all links are valid:

testlink validate

Framework Agnostic

Works with Pest, PHPUnit, or both in the same project. Use your preferred testing framework.

Benefits

Having explicit coverage links provides:

1. Documentation - Tests self-document which production code they cover
2. IDE Navigation - Jump from tests to production code
3. Refactoring Safety - Know which tests are affected when changing methods
4. Test Discovery - Find all tests covering a specific method
5. Gap Detection - Identify methods without test coverage

Package Architecture

TestLink works with test-attributes to provide complete bidirectional linking:

Package	Contains	Used In	Install As
testlink	#[TestedBy] attribute, CLI tools, Pest methods	Production code + Development	require (production)
test-attributes	#[LinksAndCovers], #[Links] attributes	Test code only	Auto-installed with testlink

Why production dependency?

If you use #[TestedBy] on production code, PHP needs the attribute class available when loading those classes. Install testlink as a production dependency to ensure this.