PHPUnit setup in Laravel - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

Understanding PHPUnit Test Discovery in Laravel

Given a Laravel project with PHPUnit installed, which folder does Laravel automatically scan to find test classes when running php artisan test?

A The <code>database/tests</code> directory

B The <code>tests</code> directory

C The <code>resources/tests</code> directory

D The <code>app/Tests</code> directory

💡 Hint

Think about where Laravel places test files by default.

Laravel places all test classes inside the tests directory at the project root. This is where PHPUnit looks for tests when running php artisan test.

📝 Syntax

intermediate

Correct PHPUnit Test Method Signature in Laravel

Which of the following is the correct way to define a test method inside a Laravel PHPUnit test class?

A public function testUserCreation() {}

B function testUserCreation() {}

C public testUserCreation() {}

D private function testUserCreation() {}

💡 Hint

Test methods must be accessible to PHPUnit and follow naming conventions.

Test methods must be public and start with test or have the @test annotation. Option A follows this rule.

❓ state_output

advanced

Output of Running a Failing Test in Laravel

What output will you see in the terminal if a Laravel PHPUnit test method contains $this->assertTrue(false);?

Laravel

<?php

use Tests\TestCase;

class ExampleTest extends TestCase
{
    public function testFailure()
    {
        $this->assertTrue(false);
    }
}

A A syntax error because <code>assertTrue</code> is not defined

B A success message showing all tests passed

C No output because the test is skipped by default

D A failure message showing the test <code>testFailure</code> failed with an assertion error

💡 Hint

Think about what happens when an assertion fails in PHPUnit.

When $this->assertTrue(false); runs, the assertion fails. PHPUnit reports this as a failed test with details.

🔧 Debug

advanced

Identifying the Cause of a PHPUnit Configuration Error in Laravel

You run php artisan test but get the error: Could not find a matching version of package phpunit/phpunit. What is the most likely cause?

A PHPUnit is not installed or missing from <code>composer.json</code> dependencies

B The <code>tests</code> directory is missing

C The <code>phpunit.xml</code> file is corrupted

D The Laravel version is too old to support PHPUnit

💡 Hint

Check your project's dependencies and composer setup.

This error usually means PHPUnit is not installed or not listed in the composer.json file. Running composer require --dev phpunit/phpunit fixes it.

🧠 Conceptual

expert

Understanding Laravel's Test Database Refresh Behavior

When using the RefreshDatabase trait in a Laravel PHPUnit test, what happens before each test method runs?

A The database connection is closed but data remains unchanged

B Only the tables used in the test are truncated

C The database is migrated fresh, rolling back and re-running all migrations

D The database is backed up but not modified

💡 Hint

Think about how Laravel ensures a clean database state for tests.

The RefreshDatabase trait runs all migrations fresh before each test, ensuring a clean database state.