src/Configuration/ActionConfigPass.php
private function doNormalizeDefaultActionsConfig(array $actionsConfig, $view)
    {
        $defaultActionsConfig = $this->getDefaultActionsConfig($view);

        foreach ($actionsConfig as $actionName => $actionConfig) {
            if (\array_key_exists($actionName, $defaultActionsConfig)) {
                // remove null config options but maintain empty options (this allows to set an empty label for the action)
                $actionConfig = \array_filter($actionConfig, function ($element) {
                    return null !== $element;
                });
                $actionsConfig[$actionName] = \array_merge($defaultActionsConfig[$actionName], $actionConfig);
            }
        }

        return $actionsConfig;
    }
private function doNormalizeDefaultActionsConfig(array $actionsConfig, $view)
    {
        $defaultActionsConfig = $this->getDefaultActionsConfig($view);

        foreach ($actionsConfig as $actionName => $actionConfig) {
            if (\array_key_exists($actionName, $defaultActionsConfig)) {
                // remove null config options but maintain empty options (this allows to set an empty label for the action)
                $actionConfig = \array_filter($actionConfig, function ($element) {
                    return null !== $element;
                });
                $actionsConfig[$actionName] = \array_merge($defaultActionsConfig[$actionName], $actionConfig);
            }
        }

        return $actionsConfig;
    }
If the user overrides the configuration of a default action, they usually
define just the options they want to change. For example:
actions: ['delete', 'list'] just to redefine the order
actions: [ { name: 'list', label: 'Listing' }] just to redefine the label.

For that reason, this method merges the full configuration of the default
actions with the new action configuration. This means that you get the
default value for any option that you don't explicitly set (e.g. the icon
or the CSS class).

@param array  $actionsConfig
@param string $view

@return array