DotsUnited\BundleFu\Tests\Filter\CallbackFilterTest::testCallbackFilter PHP Method

    public function testCallbackFilter()
    {
        $called = false;
        $callback = function () use(&$called) {
            $called = true;
            return 'bar';
        };
        $filter = new CallbackFilter($callback);
        $result = $filter->filter('foo');
        $this->assertTrue($called);
        $this->assertEquals('bar', $result);
    }