---
name: phpunit-skill-8baa6d93c0d9
description: >
  Generates PHPUnit tests in PHP. Covers assertions, data providers, mocking,
  and test doubles. Use when user mentions "PHPUnit", "TestCase", "assertEquals",
  "PHP test". Triggers on: "PHPUnit", "TestCase PHP", "assertEquals PHP",
  "PHP unit test".
languages:
  - PHP
category: unit-testing
license: MIT
metadata:
  author: TestMu AI
  version: "1.0"
---

# PHPUnit Testing Skill

## Core Patterns

### Basic Test

```php
<?php
use PHPUnit\Framework\TestCase;

class CalculatorTest extends TestCase
{
    private Calculator $calculator;

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

    public function testAddition(): void
    {
        $this->assertEquals(5, $this->calculator->add(2, 3));
    }

    public function testDivideByZero(): void
    {
        $this->expectException(\DivisionByZeroError::class);
        $this->calculator->divide(10, 0);
    }

    public function testMultipleAssertions(): void
    {
        $this->assertSame(4, $this->calculator->add(2, 2));
        $this->assertSame(0, $this->calculator->subtract(2, 2));
        $this->assertSame(6, $this->calculator->multiply(2, 3));
    }
}
```

### Data Providers

```php
/**
 * @dataProvider additionProvider
 */
public function testAdd(int $a, int $b, int $expected): void
{
    $this->assertEquals($expected, $this->calculator->add($a, $b));
}

public static function additionProvider(): array
{
    return [
        'positive numbers' => [2, 3, 5],
        'negative numbers' => [-1, -1, -2],
        'zeros'            => [0, 0, 0],
        'mixed'            => [10, -5, 5],
    ];
}
```

### Assertions

```php
$this->assertEquals($expected, $actual);
$this->assertSame($expected, $actual);          // Strict type
$this->assertNotEquals($unexpected, $actual);
$this->assertTrue($condition);
$this->assertFalse($condition);
$this->assertNull($value);
$this->assertNotNull($value);
$this->assertCount(3, $array);
$this->assertContains('item', $array);
$this->assertArrayHasKey('key', $array);
$this->assertInstanceOf(MyClass::class, $obj);
$this->assertStringContainsString('sub', $string);
$this->assertMatchesRegularExpression('/\d+/', $string);
$this->assertEmpty($collection);
$this->assertGreaterThan(5, $value);
$this->assertJsonStringEqualsJsonString($expected, $actual);
```

### Mocking

```php
public function testCreateUser(): void
{
    $mockRepo = $this->createMock(UserRepository::class);
    $mockRepo->expects($this->once())
        ->method('save')
        ->with($this->isInstanceOf(User::class))
        ->willReturn(new User(1, 'Alice'));

    $mockEmail = $this->createMock(EmailService::class);
    $mockEmail->expects($this->once())
        ->method('sendWelcome')
        ->with('alice@test.com');

    $service = new UserService($mockRepo, $mockEmail);
    $result = $service->createUser('alice@test.com', 'Alice');

    $this->assertEquals(1, $result->getId());
}
```

### Lifecycle

```php
public static function setUpBeforeClass(): void { }   // Once before all
protected function setUp(): void { }                    // Before each test
protected function tearDown(): void { }                 // After each test
public static function tearDownAfterClass(): void { }  // Once after all
```

### Anti-Patterns

| Bad | Good | Why |
|-----|------|-----|
| `assertEquals` for strict | `assertSame` for type+value | Type coercion |
| No data providers | `@dataProvider` | DRY |
| Global state | `setUp()`/`tearDown()` | Isolation |
| No groups | `@group smoke` | Run subsets |

## Setup: `composer require --dev phpunit/phpunit`
## Run: `./vendor/bin/phpunit` or `./vendor/bin/phpunit --group smoke`
## Config: `phpunit.xml` with testsuites and coverage

## Deep Patterns

See `reference/playbook.md` for production-grade patterns:

| Section | What You Get |
|---------|-------------|
| §1 Project Setup | composer.json, phpunit.xml with suites, coverage config, project structure |
| §2 Test Patterns | Assertions, #[DataProvider], Generator yields, strict comparisons |
| §3 Mocking | createMock with callbacks, Mockery spies, consecutive returns |
| §4 Test Doubles | In-memory fakes, repository pattern, test helpers |
| §5 Faker & Fixtures | TestDataFactory with overrides, bulk generation |
| §6 Exception Testing | Detailed exception assertions, warning testing |
| §7 HTTP & API Testing | Symfony WebTestCase, auth, validation, pagination |
| §8 Database Testing | Transaction rollback, repository integration, Doctrine |
| §9 CI/CD Integration | GitHub Actions with MySQL/Redis, coverage thresholds |
| §10 Debugging Table | 12 common problems with causes and fixes |
| §11 Best Practices | 14-item production PHP testing checklist |


---
Source attribution: LambdaTest
Original project: https://github.com/LambdaTest/agent-skills
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2026 Gabriel Moreira

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: LambdaTest
Original project: https://github.com/LambdaTest/agent-skills
Attribution basis: Upstream repository explicitly recorded in package mirror path

Fields of work: Development & Engineering
Roles: Backend Developer, Frontend Developer, QA / Test Engineer
Specialties: Testing
Tools: Phpunit
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: b7fb404f26ea695e1545681ff73d35d6c445b8345102850a628c93d092d7f434