Testing

CodeIgniter has been built to make testing both the framework and your application as simple as possible. Support for PHPUnit is built in, and the framework provides a number of convenient helper methods to make testing every aspect of your application as painless as possible.

System Set Up
- Installing PHPUnit
  - Composer
  - Phar
Testing Your Application

System Set Up 

Installing PHPUnit 

CodeIgniter uses PHPUnit as the basis for all of its testing. There are two ways to install PHPUnit to use within your system.

Composer 

The recommended method is to install it in your project using Composer. While it’s possible to install it globally we do not recommend it, since it can cause compatibility issues with other projects on your system as time goes on.

Ensure that you have Composer installed on your system. From the project root (the directory that contains the application and system directories) type the following from the command line:

> composer require --dev phpunit/phpunit

This will install the correct version for your current PHP version. Once that is done, you can run all of the tests for this project by typing:

> vendor/bin/phpunit

If you are using Windows, use the following command:

> vendor\bin\phpunit

Phar 

The other option is to download the .phar file from the PHPUnit site. This is a standalone file that should be placed within your project root.

Testing Your Application 

PHPUnit Configuration 

The framework has a phpunit.xml.dist file in the project root. This controls unit testing of the framework itself. If you provide your own phpunit.xml, it will over-ride this.

Your phpunit.xml should exclude the system folder, as well as any vendor or ThirdParty folders, if you are unit testing your application.

The Test Class 

In order to take advantage of the additional tools provided, your tests must extend CIUnitTestCase. All tests are expected to be located in the tests/app directory by default.

To test a new library, Foo, you would create a new file at tests/app/Libraries/FooTest.php:

<?php

namespace App\Libraries;

use CodeIgniter\Test\CIUnitTestCase;

class FooTest extends CIUnitTestCase
{
    public function testFooNotBar()
    {
        // ...
    }
}

To test one of your models, you might end up with something like this in tests/app/Models/OneOfMyModelsTest.php:

<?php

namespace App\Models;

use CodeIgniter\Test\CIUnitTestCase;

class OneOfMyModelsTest extends CIUnitTestCase
{
    public function testFooNotBar()
    {
        // ...
    }
}

You can create any directory structure that fits your testing style/needs. When namespacing the test classes, remember that the app directory is the root of the App namespace, so any classes you use must have the correct namespace relative to App.

Note

Namespaces are not strictly required for test classes, but they are helpful to ensure no class names collide.

When testing database results, you must use the DatabaseTestTrait in your class.

Staging 

Most tests require some preparation in order to run correctly. PHPUnit’s TestCase provides four methods to help with staging and clean up:

public static function setUpBeforeClass(): void
public static function tearDownAfterClass(): void

protected function setUp(): void
protected function tearDown(): void

The static methods setUpBeforeClass() and tearDownAfterClass() run before and after the entire test case, whereas the protected methods setUp() and tearDown() run between each test.

If you implement any of these special functions make sure you run their parent as well so extended test cases do not interfere with staging:

<?php

namespace App\Models;

use CodeIgniter\Test\CIUnitTestCase;

final class OneOfMyModelsTest extends CIUnitTestCase
{
    protected function setUp(): void
    {
        parent::setUp(); // Do not forget

        helper('text');
    }

    // ...
}

Traits 

A common way to enhance your tests is by using traits to consolidate staging across different test cases. CIUnitTestCase will detect any class traits and look for staging methods to run named for the trait itself (i.e. setUp{NameOfTrait}() and tearDown{NameOfTrait}()).

For example, if you needed to add authentication to some of your test cases you could create an authentication trait with a set up method to fake a logged in user:

<?php

trait AuthTrait
{
    protected function setUpAuthTrait()
    {
        $user = $this->createFakeUser();
        $this->logInUser($user);
    }

    // ...
}

use CodeIgniter\Test\CIUnitTestCase;

final class AuthenticationFeatureTest extends CIUnitTestCase
{
    use AuthTrait;

    // ...
}

Additional Assertions 

CIUnitTestCase provides additional unit testing assertions that you might find useful.

assertLogged($level, $expectedMessage)

Ensure that something you expected to be logged actually was:

<?php

$config = new LoggerConfig();
$logger = new Logger($config);

// ... do something that you expect a log entry from
$logger->log('error', "That's no moon");

$this->assertLogged('error', "That's no moon");

assertEventTriggered($eventName)

Ensure that an event you expected to be triggered actually was:

<?php

Events::on('foo', static function ($arg) use (&$result) {
    $result = $arg;
});

Events::trigger('foo', 'bar');

$this->assertEventTriggered('foo');

assertHeaderEmitted($header, $ignoreCase = false)

Ensure that a header or cookie was actually emitted:

<?php

$response->setCookie('foo', 'bar');

ob_start();
$this->response->send();
$output = ob_get_clean(); // in case you want to check the actual body

$this->assertHeaderEmitted('Set-Cookie: foo=bar');

Note

the test case with this should be run as a separate process in PHPunit.

assertHeaderNotEmitted($header, $ignoreCase = false)

Ensure that a header or cookie was not emitted:

<?php

$response->setCookie('foo', 'bar');

ob_start();
$this->response->send();
$output = ob_get_clean(); // in case you want to check the actual body

$this->assertHeaderNotEmitted('Set-Cookie: banana');

Note

the test case with this should be run as a separate process in PHPunit.

assertCloseEnough($expected, $actual, $message = ‘’, $tolerance = 1)

For extended execution time testing, tests that the absolute difference between expected and actual time is within the prescribed tolerance:

<?php

$timer = new Timer();
$timer->start('longjohn', strtotime('-11 minutes'));
$this->assertCloseEnough(11 * 60, $timer->getElapsedTime('longjohn'));

The above test will allow the actual time to be either 660 or 661 seconds.

assertCloseEnoughString($expected, $actual, $message = ‘’, $tolerance = 1)

For extended execution time testing, tests that the absolute difference between expected and actual time, formatted as strings, is within the prescribed tolerance:

<?php

$timer = new Timer();
$timer->start('longjohn', strtotime('-11 minutes'));
$this->assertCloseEnoughString(11 * 60, $timer->getElapsedTime('longjohn'));

The above test will allow the actual time to be either 660 or 661 seconds.

Accessing Protected/Private Properties 

When testing, you can use the following setter and getter methods to access protected and private methods and properties in the classes that you are testing.

getPrivateMethodInvoker($instance, $method)

Enables you to call private methods from outside the class. This returns a function that can be called. The first parameter is an instance of the class to test. The second parameter is the name of the method you want to call.

<?php

// Create an instance of the class to test
$obj = new Foo();

// Get the invoker for the 'privateMethod' method.
$method = $this->getPrivateMethodInvoker($obj, 'privateMethod');

// Test the results
$this->assertEquals('bar', $method('param1', 'param2'));

getPrivateProperty($instance, $property)

Retrieves the value of a private/protected class property from an instance of a class. The first parameter is an instance of the class to test. The second parameter is the name of the property.

<?php

// Create an instance of the class to test
$obj = new Foo();

// Test the value
$this->assertEquals('bar', $this->getPrivateProperty($obj, 'baz'));

setPrivateProperty($instance, $property, $value)

Set a protected value within a class instance. The first parameter is an instance of the class to test. The second parameter is the name of the property to set the value of. The third parameter is the value to set it to:

<?php

// Create an instance of the class to test
$obj = new Foo();

// Set the value
$this->setPrivateProperty($obj, 'baz', 'oops!');

// Do normal testing...

Mocking Services 

You will often find that you need to mock one of the services defined in app/Config/Services.php to limit your tests to only the code in question, while simulating various responses from the services. This is especially true when testing controllers and other integration testing. The Services class provides the following methods to simplify this.

Services::injectMock()

This method allows you to define the exact instance that will be returned by the Services class. You can use this to set properties of a service so that it behaves in a certain way, or replace a service with a mocked class.

<?php

use CodeIgniter\Test\CIUnitTestCase;
use Config\Services;

final class SomeTest extends CIUnitTestCase
{
    public function testSomething()
    {
        $curlrequest = $this->getMockBuilder('CodeIgniter\HTTP\CURLRequest')
            ->setMethods(['request'])
            ->getMock();
        Services::injectMock('curlrequest', $curlrequest);

        // Do normal testing here....
    }
}

The first parameter is the service that you are replacing. The name must match the function name in the Services class exactly. The second parameter is the instance to replace it with.

Services::reset()

Removes all mocked classes from the Services class, bringing it back to its original state.

You can also use the $this->resetServices() method that CIUnitTestCase provides.

Services::resetSingle(string $name)

Removes any mock and shared instances for a single service, by its name.

Note

The Cache, Email and Session services are mocked by default to prevent intrusive testing behavior. To prevent these from mocking remove their method callback from the class property: $setUpMethods = ['mockEmail', 'mockSession'];

Mocking Factory Instances 

Similar to Services, you may find yourself needing to supply a pre-configured class instance during testing that will be used with Factories. Use the same Factories::injectMock() and Factories::reset() static methods like Services, but they take an additional preceding parameter for the component name:

<?php

use CodeIgniter\Config\Factories;
use CodeIgniter\Test\CIUnitTestCase;

final class SomeTest extends CIUnitTestCase
{
    protected function setUp(): void
    {
        parent::setUp();

        $model = new MockUserModel();
        Factories::injectMock('models', 'App\Models\UserModel', $model);
    }
}

Note

All component Factories are reset by default between each test. Modify your test case’s $setUpMethods if you need instances to persist.

Stream Filters 

CITestStreamFilter provides an alternate to these helper methods.

You may need to test things that are difficult to test. Sometimes, capturing a stream, like PHP’s own STDOUT, or STDERR, might be helpful. The CITestStreamFilter helps you capture the output from the stream of your choice.

An example demonstrating this inside one of your test cases:

<?php

use CodeIgniter\CLI\CLI;
use CodeIgniter\Test\CIUnitTestCase;
use CodeIgniter\Test\Filters\CITestStreamFilter;

final class SomeTest extends CIUnitTestCase
{
    protected function setUp(): void
    {
        CITestStreamFilter::$buffer = '';
        $this->stream_filter        = stream_filter_append(STDOUT, 'CITestStreamFilter');
    }

    protected function tearDown(): void
    {
        stream_filter_remove($this->stream_filter);
    }

    public function testSomeOutput(): void
    {
        CLI::write('first.');

        $expected = "first.\n";
        $this->assertSame($expected, CITestStreamFilter::$buffer);
    }
}