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    <h3>Editing: VarDumperTestTrait.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\VarDumper\Test;

use Symfony\Component\VarDumper\Cloner\VarCloner;
use Symfony\Component\VarDumper\Dumper\CliDumper;

/**
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 */
trait VarDumperTestTrait
{
    /**
     * @internal
     */
    private $varDumperConfig = [
        'casters' =&gt; [],
        'flags' =&gt; null,
    ];

    protected function setUpVarDumper(array $casters, ?int $flags = null): void
    {
        $this-&gt;varDumperConfig['casters'] = $casters;
        $this-&gt;varDumperConfig['flags'] = $flags;
    }

    /**
     * @after
     */
    protected function tearDownVarDumper(): void
    {
        $this-&gt;varDumperConfig['casters'] = [];
        $this-&gt;varDumperConfig['flags'] = null;
    }

    public function assertDumpEquals($expected, $data, int $filter = 0, string $message = '')
    {
        $this-&gt;assertSame($this-&gt;prepareExpectation($expected, $filter), $this-&gt;getDump($data, null, $filter), $message);
    }

    public function assertDumpMatchesFormat($expected, $data, int $filter = 0, string $message = '')
    {
        $this-&gt;assertStringMatchesFormat($this-&gt;prepareExpectation($expected, $filter), $this-&gt;getDump($data, null, $filter), $message);
    }

    protected function getDump($data, $key = null, int $filter = 0): ?string
    {
        if (null === $flags = $this-&gt;varDumperConfig['flags']) {
            $flags = getenv('DUMP_LIGHT_ARRAY') ? CliDumper::DUMP_LIGHT_ARRAY : 0;
            $flags |= getenv('DUMP_STRING_LENGTH') ? CliDumper::DUMP_STRING_LENGTH : 0;
            $flags |= getenv('DUMP_COMMA_SEPARATOR') ? CliDumper::DUMP_COMMA_SEPARATOR : 0;
        }

        $cloner = new VarCloner();
        $cloner-&gt;addCasters($this-&gt;varDumperConfig['casters']);
        $cloner-&gt;setMaxItems(-1);
        $dumper = new CliDumper(null, null, $flags);
        $dumper-&gt;setColors(false);
        $data = $cloner-&gt;cloneVar($data, $filter)-&gt;withRefHandles(false);
        if (null !== $key &amp;&amp; null === $data = $data-&gt;seek($key)) {
            return null;
        }

        return rtrim($dumper-&gt;dump($data, true));
    }

    private function prepareExpectation($expected, int $filter): string
    {
        if (!\is_string($expected)) {
            $expected = $this-&gt;getDump($expected, null, $filter);
        }

        return rtrim($expected);
    }
}
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