The Easiest Way to Use Any Coding Standard

// ecs.php
use PhpCsFixer\Fixer\ArrayNotation\ArraySyntaxFixer;
use Symplify\EasyCodingStandard\Config\ECSConfig;
use Symplify\EasyCodingStandard\ValueObject\Set\SetList;

return static function (ECSConfig $ecsConfig): void {
    // A. full sets
    $ecsConfig->sets([SetList::PSR_12]);

    // B. standalone rule
    $ecsConfig->ruleWithConfiguration(ArraySyntaxFixer::class, [
        'syntax' => 'short',
    ]);
};

use PhpCsFixer\Fixer\ArrayNotation\ArraySyntaxFixer;
use Symplify\EasyCodingStandard\Config\ECSConfig;

return static function (ECSConfig $ecsConfig): void {
    // alternative to CLI arguments, easier to maintain and extend
    $ecsConfig->paths([__DIR__ . '/src', __DIR__ . '/tests']);

    // bear in mind that this will override SetList skips if one was previously imported
    // this is result of design decision in symfony https://github.com/symfony/symfony/issues/26713
    $ecsConfig->skip([
        // skip paths with legacy code
        __DIR__ . '/packages/*/src/Legacy',

        ArraySyntaxFixer::class => [
            // path to file (you can copy this from error report)
            __DIR__ . '/packages/EasyCodingStandard/packages/SniffRunner/src/File/File.php',

            // or multiple files by path to match against "fnmatch()"
            __DIR__ . '/packages/*/src/Command',
        ],

        // skip rule completely
        ArraySyntaxFixer::class,

        // just single one part of the rule?
        ArraySyntaxFixer::class . '.SomeSingleOption',

        // ignore specific error message
        'Cognitive complexity for method "addAction" is 13 but has to be less than or equal to 8.',
    ]);

    // scan other file extendsions; [default: [php]]
    $ecsConfig->fileExtensions(['php', 'phpt']);

    // configure cache paths & namespace - useful for Gitlab CI caching, where getcwd() produces always different path
    // [default: sys_get_temp_dir() . '/_changed_files_detector_tests']
    $ecsConfig->cacheDirectory('.ecs_cache');

    // [default: \Nette\Utils\Strings::webalize(getcwd())']
    $ecsConfig->cacheNamespace('my_project_namespace');

    // indent and tabs/spaces
    // [default: spaces]
    $ecsConfig->indentation('tab');

    // [default: PHP_EOL]; other options: "\n"
    $ecsConfig->lineEnding("\r\n");
};

use Symplify\EasyCodingStandard\Config\ECSConfig;

return static function (ECSConfig $ecsConfig): void {
    $ecsConfig->parallel();
};