Tests: enable non-integration tests to use TitleFactory service.

This change implements two things that can be combined to allow
the usage of services like the TitleFactory in subclasses of
MediaWikiUnitTestCase:

1) This adds getServiceContainer() to the MediaWikiUnitTestCase base
   class, to mirror the method of the same name on
   MediaWikiIntegrationtest case, along with a a setService() method
   for defining service objects for use in tests.

2) This adds makeMockTitleFactory() to the MockTitleTrait, to allow
   tests to esaily define the TitleFactory service.

Making services available through a service container primarily
benefits code that relies on ObjectFactory, like REST handlers.

Needed-By: Iac113a9e766e38b2d19ae99b7e448548a515469e
Change-Id: Ida6c37c7133b9e3887268025daf6e5b7c1340e52

1 files changed, 72 insertions, 0 deletions

diff --git a/tests/phpunit/MediaWikiUnitTestCase.php b/tests/phpunit/MediaWikiUnitTestCase.php
index d91a0d6b4abe..a4b438c997c0 100644
--- a/tests/phpunit/MediaWikiUnitTestCase.php
+++ b/tests/phpunit/MediaWikiUnitTestCase.php
@@ -30,6 +30,7 @@ use MediaWiki\Settings\SettingsBuilder;
 use PHPUnit\Framework\Exception;
 use PHPUnit\Framework\TestCase;
 use Wikimedia\ObjectFactory\ObjectFactory;
+use Wikimedia\Services\NoSuchServiceException;
 
 /**
  * Base class for unit tests.
@@ -47,6 +48,13 @@ abstract class MediaWikiUnitTestCase extends TestCase {
 	private static $originalGlobals;
 	private static $unitGlobals;
 
+	private ?MediaWikiServices $serviceContainer = null;
+
+	/**
+	 * @var array<string,object>
+	 */
+	private array $services = [];
+
 	/**
 	 * List of allowed globals to allow in MediaWikiUnitTestCase.
 	 *
@@ -174,4 +182,68 @@ abstract class MediaWikiUnitTestCase extends TestCase {
 		SettingsBuilder::enableAccessAfterUnitTests();
 	}
 
+	/**
+	 * Returns a mock service container.
+	 * To populate the service container with service objects, use setService().
+	 *
+	 * @since 1.43
+	 */
+	protected function getServiceContainer(): MediaWikiServices {
+		if ( !$this->serviceContainer ) {
+			$this->serviceContainer = $this->getMockBuilder( MediaWikiServices::class )
+				->setConstructorArgs( [ new HashConfig() ] )
+				->onlyMethods( [
+					'getService',
+					'disableStorage',
+					'isStorageDisabled',
+					'redefineService',
+					'resetServiceForTesting',
+					'resetChildProcessServices',
+					'peekService'
+				] )
+				->getMock();
+
+			$this->serviceContainer
+				->method( 'getService' )
+				->willReturnCallback( function ( $name ) {
+					return $this->getService( $name );
+				} );
+		}
+
+		return $this->serviceContainer;
+	}
+
+	/**
+	 * Returns a service previously defined with setService().
+	 *
+	 * @param string $name
+	 *
+	 * @return mixed The service instance
+	 */
+	protected function getService( string $name ) {
+		if ( !isset( $this->services[$name] ) ) {
+			throw new NoSuchServiceException( $name );
+		}
+
+		if ( is_callable( $this->services[$name] ) ) {
+			$func = $this->services[$name];
+			$this->services[$name] = $func( $this->serviceContainer );
+		}
+
+		return $this->services[$name];
+	}
+
+	/**
+	 * Register a service object with the service container returned by
+	 * getServiceContainer().
+	 *
+	 * @param string $name
+	 * @param mixed $service
+	 *
+	 * @since 1.43
+	 */
+	protected function setService( string $name, $service ) {
+		$this->services[$name] = $service;
+	}
+
 }