class Debug

1. 8.x drupal/core/vendor/symfony/debug/Symfony/Component/Debug/Debug.php \Symfony\Component\Debug\Debug
2. 8.x drupal/core/vendor/doctrine/common/lib/Doctrine/Common/Util/Debug.php \Doctrine\Common\Util\Debug

CommentLinksTest::setEnvironment in drupal/core/modules/comment/lib/Drupal/comment/Tests/CommentLinksTest.php

Re-configures the environment, module settings, and user permissions.

ExceptionController::on500Html in drupal/core/lib/Drupal/Core/Controller/ExceptionController.php

Processes a generic exception into an HTTP 500 response.

hook_watchdog in drupal/core/modules/system/system.api.php

Log an event message.

Kernel::getContainerClass in drupal/core/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/Kernel.php

Gets the container class.

SimpletestResultsForm::buildForm in drupal/core/modules/simpletest/lib/Drupal/simpletest/Form/SimpletestResultsForm.php

Form constructor.

... See full list

class Debug {
  private static $enabled = false;

  /**
   * Enables the debug tools.
   *
   * This method registers an error handler and an exception handler.
   *
   * If the Symfony ClassLoader component is available, a special
   * class loader is also registered.
   *
   * @param integer $errorReportingLevel The level of error reporting you want
   * @param Boolean $displayErrors       Whether to display errors (for development) or just log them (for production)
   */
  public static function enable($errorReportingLevel = null, $displayErrors = true) {
    if (static::$enabled) {
      return;
    }
    static::$enabled = true;
    error_reporting(-1);
    ErrorHandler::register($errorReportingLevel, $displayErrors);
    if ('cli' !== php_sapi_name()) {
      ExceptionHandler::register();

      // CLI - display errors only if they're not already logged to STDERR
    }
    elseif ($displayErrors && (!ini_get('log_errors') || ini_get('error_log'))) {
      ini_set('display_errors', 1);
    }
    if (class_exists('Symfony\\Component\\ClassLoader\\DebugClassLoader')) {
      DebugClassLoader::enable();
    }
  }

}