diff --git a/src/scheduler/Task.php b/src/scheduler/Task.php
index 9d3e5a6fe..85c0da6c7 100644
--- a/src/scheduler/Task.php
+++ b/src/scheduler/Task.php
@@ -57,17 +57,13 @@ abstract class Task{
 
 	/**
 	 * Actions to execute when run
-	 *
-	 * @return void
 	 */
-	abstract public function onRun();
+	abstract public function onRun() : void;
 
 	/**
 	 * Actions to execute if the Task is cancelled
-	 *
-	 * @return void
 	 */
-	public function onCancel(){
+	public function onCancel() : void{
 
 	}
 }
diff --git a/tests/plugins/TesterPlugin/src/pmmp/TesterPlugin/CheckTestCompletionTask.php b/tests/plugins/TesterPlugin/src/pmmp/TesterPlugin/CheckTestCompletionTask.php
index 49ee205b0..9cebd98a4 100644
--- a/tests/plugins/TesterPlugin/src/pmmp/TesterPlugin/CheckTestCompletionTask.php
+++ b/tests/plugins/TesterPlugin/src/pmmp/TesterPlugin/CheckTestCompletionTask.php
@@ -34,7 +34,7 @@ class CheckTestCompletionTask extends Task{
 		$this->plugin = $plugin;
 	}
 
-	public function onRun(){
+	public function onRun() : void{
 		$test = $this->plugin->getCurrentTest();
 		if($test === null){
 			if(!$this->plugin->startNextTest()){