Symfony 7.4 VarDumper Component

GitHub: https://github.com/symfony/var-dumper Docs: https://symfony.com/doc/7.4/components/var_dumper.html

Quick Reference

Installation

bash

# Standalone
composer require --dev symfony/var-dumper

# With Symfony (recommended)
composer require --dev symfony/debug-bundle

Basic Usage - dump() and dd()

php

// dump() - outputs variable and returns it (chainable)
dump($someVar);
dump($object)->someMethod();  // returns passed value

// dd() - "dump and die" - dumps then exits
dd($var1, $var2);

Custom Handler

php

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

VarDumper::setHandler(function (mixed $var): ?string {
    $cloner = new VarCloner();
    $dumper = 'cli' === PHP_SAPI ? new CliDumper() : new HtmlDumper();
    return $dumper->dump($cloner->cloneVar($var));
});

Dump Server (Separate Debug Output)

bash

# Start server
php bin/console server:dump

# Or use standalone binary
./vendor/bin/var-dump-server

yaml

# config/packages/debug.yaml
debug:
    dump_destination: "tcp://%env(VAR_DUMPER_SERVER)%"

Twig Integration

twig

{% dump foo.bar %}      {# Dumps to toolbar #}
{{ dump(foo.bar) }}     {# Dumps inline in template #}

Testing with VarDumperTestTrait

php

use Symfony\Component\VarDumper\Test\VarDumperTestTrait;

class ExampleTest extends TestCase
{
    use VarDumperTestTrait;

    public function testDump(): void
    {
        $this->assertDumpEquals('[123, "foo"]', [123, 'foo']);
    }
}

Cloner Configuration

php

$cloner = new VarCloner();
$cloner->setMaxItems(100);      // Max items cloned (-1 = unlimited)
$cloner->setMinDepth(2);        // Minimum depth guaranteed
$cloner->setMaxString(1000);    // Max string length (-1 = unlimited)

Dump as String

php

$cloner = new VarCloner();
$dumper = new CliDumper();
$output = $dumper->dump($cloner->cloneVar($var), true);  // returns string

Full Documentation

For complete details including all Dumper types, Caster implementation, Stub classes, dump server configuration, PHPUnit integration, property prefixes, and advanced customization, see references/var-dumper.md.