PHP Testing Skill

Atomic skill for mastering PHP testing strategies

Overview

Comprehensive skill for PHP testing covering PHPUnit 11, Pest 3, TDD methodology, mocking strategies, and CI/CD integration.

Skill Parameters

Input Validation

interface SkillParams {
  topic:
    | "phpunit"          // PHPUnit framework
    | "pest"             // Pest framework
    | "mocking"          // Mockery, Prophecy
    | "tdd"              // Test-driven development
    | "integration"      // Database, API testing
    | "ci-cd";           // GitHub Actions, GitLab CI

  level: "beginner" | "intermediate" | "advanced";
  framework?: "laravel" | "symfony" | "none";
  coverage_goal?: number;
}

Validation Rules

validation:
  topic:
    required: true
    allowed: [phpunit, pest, mocking, tdd, integration, ci-cd]
  level:
    required: true
  framework:
    default: "none"

Learning Modules

Module 1: PHPUnit Fundamentals

beginner:
  - Test case structure
  - Basic assertions
  - Running tests

intermediate:
  - Data providers
  - Fixtures (setUp/tearDown)
  - Test doubles

advanced:
  - Attributes (#[Test], #[DataProvider])
  - Code coverage
  - Parallel execution

Module 2: Pest Framework

beginner:
  - Expectations syntax
  - Test organization
  - Groups and filtering

intermediate:
  - Higher-order tests
  - Datasets
  - Hooks

advanced:
  - Mutation testing (--mutate)
  - Architecture testing
  - Custom expectations

Module 3: Mocking Strategies

beginner:
  - Mock basics
  - Stubs vs mocks
  - Simple expectations

intermediate:
  - Partial mocks
  - Spies
  - Argument matching

advanced:
  - Mock chains
  - Return callbacks
  - Exception testing

Error Handling & Retry Logic

errors:
  TEST_FAILURE:
    code: "TEST_001"
    recovery: "Compare expected vs actual, check setup"

  MOCK_ERROR:
    code: "TEST_002"
    recovery: "Verify mock expectations and injection"

  FLAKY_TEST:
    code: "TEST_003"
    recovery: "Check isolation, fix race conditions"

retry:
  max_attempts: 2
  backoff:
    type: linear
    delay_ms: 100

Code Examples

PHPUnit Test (PHP 8.2+)

<?php
declare(strict_types=1);

namespace Tests\Unit;

use App\Services\Calculator;
use PHPUnit\Framework\TestCase;
use PHPUnit\Framework\Attributes\Test;
use PHPUnit\Framework\Attributes\DataProvider;

final class CalculatorTest extends TestCase
{
    private Calculator $calculator;

    protected function setUp(): void
    {
        $this->calculator = new Calculator();
    }

    #[Test]
    public function it_adds_two_numbers(): void
    {
        $result = $this->calculator->add(2, 3);

        $this->assertSame(5, $result);
    }

    #[Test]
    #[DataProvider('divisionProvider')]
    public function it_divides_correctly(int $a, int $b, float $expected): void
    {
        $result = $this->calculator->divide($a, $b);

        $this->assertEqualsWithDelta($expected, $result, 0.0001);
    }

    public static function divisionProvider(): array
    {
        return [
            'whole' => [10, 2, 5.0],
            'decimal' => [7, 2, 3.5],
        ];
    }

    #[Test]
    public function it_throws_on_division_by_zero(): void
    {
        $this->expectException(\DivisionByZeroError::class);

        $this->calculator->divide(10, 0);
    }
}

Pest Test

<?php
use App\Models\User;
use function Pest\Laravel\{actingAs, post, assertDatabaseHas};

describe('User Registration', function () {
    it('allows new user registration', function () {
        post('/register', [
            'name' => 'John',
            'email' => 'john@example.com',
            'password' => 'password',
            'password_confirmation' => 'password',
        ])
        ->assertRedirect('/dashboard');

        assertDatabaseHas('users', ['email' => 'john@example.com']);
    });

    it('requires valid email', function () {
        post('/register', ['email' => 'invalid'])
            ->assertSessionHasErrors('email');
    });
})->group('auth');

Mocking with Mockery

<?php
declare(strict_types=1);

namespace Tests\Unit;

use App\Services\UserService;
use App\Repositories\UserRepository;
use Mockery;
use PHPUnit\Framework\TestCase;

final class UserServiceTest extends TestCase
{
    public function test_creates_user(): void
    {
        // Arrange
        $repository = Mockery::mock(UserRepository::class);
        $repository
            ->shouldReceive('create')
            ->once()
            ->with(['name' => 'John', 'email' => 'john@test.com'])
            ->andReturn(new User(['id' => 1]));

        $service = new UserService($repository);

        // Act
        $user = $service->createUser([
            'name' => 'John',
            'email' => 'john@test.com',
        ]);

        // Assert
        $this->assertEquals(1, $user->id);
    }

    protected function tearDown(): void
    {
        Mockery::close();
    }
}

CI/CD Configuration (GitHub Actions)

name: Tests

on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Setup PHP
        uses: shivammathur/setup-php@v2
        with:
          php-version: '8.3'
          coverage: xdebug

      - name: Install dependencies
        run: composer install --no-progress

      - name: Run tests
        run: vendor/bin/phpunit --coverage-clover coverage.xml

      - name: Upload coverage
        uses: codecov/codecov-action@v3

Troubleshooting

Problem	Cause	Solution
Tests pass locally, fail in CI	Environment differences	Check PHP version, database state
Mock not called	Not injected	Verify DI, don't instantiate inside class
Database pollution	Shared state	Use RefreshDatabase trait
Slow tests	Too many DB operations	Use mocks, run parallel

Quality Metrics

Metric	Target
Code coverage	≥80%
Test speed	<5 min full suite
Flaky rate	0%
Test isolation	100%

Usage

Skill("php-testing", {topic: "mocking", level: "intermediate"})