use createStub if exists

Author: michalbundyra

tests/MockDisablerTest.php

@@ -38,7 +38,11 @@ public function testCallback()
     {
         $executed = false;
         $executedWith = null;
-        $mock = $this->createStub(Deactivatable::class);
+
+        $mock = method_exists($this, 'createStub')
+            ? $this->createStub(Deactivatable::class)
+            : $this->createMock(Deactivatable::class);
+
         $disabler = new MockDisabler($mock, static function ($disabler) use (&$executed, &$executedWith) {
             self::assertInstanceOf(MockDisabler::class, $disabler);
 

tests/MockObjectProxyTest.php

@@ -33,7 +33,9 @@ class MockObjectProxyTest extends TestCase
      */
     public function testExpects()
     {
-        $matcher = $this->createStub(Invocation::class);
+        $matcher = method_exists($this, 'createStub')
+            ? $this->createStub(Invocation::class)
+            : $this->createMock(Invocation::class);
 
         if (class_exists(ConfigurableMethod::class)) {
             if (class_exists(\PHPUnit\Runner\Version::class)