2 files changed, 54 insertions, 0 deletions
diff --git a/phpBB/phpbb/di/service_collection.php b/phpBB/phpbb/di/service_collection.php
index 8e9175e204..8c1c172e36 100644
--- a/phpBB/phpbb/di/service_collection.php
+++ b/phpBB/phpbb/di/service_collection.php
@@ -103,4 +103,35 @@ class service_collection extends \ArrayObject
 	{
 		return $this->service_classes;
 	}
+
+	/**
+	 * Returns the service associated to a class
+	 *
+	 * @return mixed
+	 * @throw \RuntimeException if the
+	 */
+	public function get_by_class($class)
+	{
+		$service_id = null;
+
+		foreach ($this->service_classes as $id => $service_class)
+		{
+			if ($service_class === $class)
+			{
+				if ($service_id !== null)
+				{
+					throw new \RuntimeException('More than one service definitions found for class "'.$class.'" in collection.');
+				}
+
+				$service_id = $id;
+			}
+		}
+
+		if ($service_id === null)
+		{
+			throw new \RuntimeException('No service found for class "'.$class.'" in collection.');
+		}
+
+		return $this->offsetGet($service_id);
+	}
 }
diff --git a/tests/di/service_collection_test.php b/tests/di/service_collection_test.php
index 5b51254a4a..5815b4367d 100644
--- a/tests/di/service_collection_test.php
+++ b/tests/di/service_collection_test.php
@@ -23,10 +23,14 @@ class phpbb_service_collection_test extends \phpbb_test_case
 		$container = new phpbb_mock_container_builder();
 		$container->set('foo', new StdClass);
 		$container->set('bar', new StdClass);
+		$container->set('baz', new StdClass);
 
 		$this->service_collection = new \phpbb\di\service_collection($container);
 		$this->service_collection->add('foo');
 		$this->service_collection->add('bar');
+		$this->service_collection->add_service_class('foo', 'foo_class');
+		$this->service_collection->add_service_class('bar', 'bar_class');
+		$this->service_collection->add_service_class('baz', 'bar_class');
 
 		parent::setUp();
 	}
@@ -44,4 +48,23 @@ class phpbb_service_collection_test extends \phpbb_test_case
 
 		$this->assertSame(array('foo', 'bar'), $service_names);
 	}
+
+	public function test_get_by_class()
+	{
+		$this->assertSame($this->service_collection['foo'], $this->service_collection->get_by_class('foo_class'));
+	}
+
+	public function test_get_by_class_many_services_exception()
+	{
+		$this->setExpectedException('RuntimeException', 'More than one service definitions found for class "bar_class" in collection.');
+
+		$this->service_collection->get_by_class('bar_class');
+	}
+
+	public function test_get_by_class_no_service_exception()
+	{
+		$this->setExpectedException('RuntimeException', 'No service found for class "baz_class" in collection.');
+
+		$this->service_collection->get_by_class('baz_class');
+	}
 }