Run tests on PHPUnit 9

Author: SimonFrings

composer.json

@@ -23,6 +23,6 @@
         "react/promise": "^3.0 || ^2.7.0 || ^1.2.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7.0 || ^6.4 || ^5.7 || ^4.8.35"
+        "phpunit/phpunit": "^9.0 || ^5.7 || ^4.8.35"
     }
 }

tests/CallableStub.php

@@ -9,7 +9,10 @@ class TestCase extends BaseTestCase
 {
     protected $loop;
 
-    public function setUp()
+    /**
+     * @before
+     */
+    public function setUpLoop()
     {
         $this->loop = Factory::create();
     }
@@ -41,7 +44,13 @@ protected function expectCallableNever()
      */
     protected function createCallableMock()
     {
-        return $this->getMockBuilder('React\Tests\Promise\Timer\CallableStub')->getMock();
+        if (method_exists('PHPUnit\Framework\MockObject\MockBuilder', 'addMethods')) {
+            // PHPUnit 9+
+            return $this->getMockBuilder('stdClass')->addMethods(array('__invoke'))->getMock();
+        } else {
+            // legacy PHPUnit 4 - PHPUnit 9
+            return $this->getMockBuilder('stdClass')->setMethods(array('__invoke'))->getMock();
+        }
     }
 
     protected function expectPromiseRejected($promise)