diff --git a/tests/Polyfills/Fixtures/ValueObjectUnionNoReturnType.php b/tests/Polyfills/Fixtures/ValueObjectUnionNoReturnType.php
index efa2387..935d445 100644
--- a/tests/Polyfills/Fixtures/ValueObjectUnionNoReturnType.php
+++ b/tests/Polyfills/Fixtures/ValueObjectUnionNoReturnType.php
@@ -28,7 +28,7 @@ public function __construct( $value ) {
 	 *
 	 * @param self|OtherClass|array $other Object to compare.
 	 *
-	 * @return bool
+	 * @return bool|null
 	 */
 	public function equalsParamUnionType( self|OtherClass|array $other ) {
 		return ( $this->value === $other->value );
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index e4076ae..7f45d03 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -46,7 +46,7 @@ static function ( $fqClassName ) {
 }
 else {
 	echo 'Please run `composer install` before attempting to run the tests.';
-	die( 1 );
+	exit( 1 );
 }
 
 /*