FilecontentFilterIterator example

namespace Symfony\Component\Finder\Tests\Iterator;

use Symfony\Component\Finder\Iterator\FilecontentFilterIterator;

class FilecontentFilterIteratorTest extends IteratorTestCase
{
    public function testAccept()
    {
        $inner = new MockFileListIterator(['test.txt']);
        $iterator = new FilecontentFilterIterator($inner, [], []);
        $this->assertIterator(['test.txt'], $iterator);
    }

    public function testDirectory()
    {
        $inner = new MockFileListIterator(['directory']);
        $iterator = new FilecontentFilterIterator($inner, ['directory'], []);
        $this->assertIterator([], $iterator);
    }

    public function testUnreadableFile()
    {

        if ($this->mode) {
            $iterator = new Iterator\FileTypeFilterIterator($iterator, $this->mode);
        }

        if ($this->names || $this->notNames) {
            $iterator = new Iterator\FilenameFilterIterator($iterator, $this->names, $this->notNames);
        }

        if ($this->contains || $this->notContains) {
            $iterator = new Iterator\FilecontentFilterIterator($iterator, $this->contains, $this->notContains);
        }

        if ($this->sizes) {
            $iterator = new Iterator\SizeRangeFilterIterator($iterator, $this->sizes);
        }

        if ($this->dates) {
            $iterator = new Iterator\DateRangeFilterIterator($iterator, $this->dates);
        }

        if ($this->filters) {