public function testAddValidator() { $service = new ServiceProvider(); // Initially empty $this->assertEmpty(Validator::$methods); $test_callback = function () { echo 'test'; }; $service->addValidator('awesome', $test_callback); $this->assertNotEmpty(Validator::$methods); $this->assertArrayHasKey('awesome', Validator::$methods); $this->assertContains($test_callback, Validator::$methods); }