[FEATURE] Add option to completely remove query-string from SearchRequest

[rr-it]

Is your feature request related to a problem? Please describe.
Removing the query-string from a SearchRequest might be used to keep e.g. the category selections while not limiting the result by a search query string anymore.

In solr v11.2 it was possible to completely remove the query-string from a SearchRequest by setting it to null.

E.g. using a custom ViewHelper:

class RemoveQueryViewHelper extends AbstractUriViewHelper
{

    /**
     * @param array $arguments
     * @param \Closure $renderChildrenClosure
     * @param RenderingContextInterface $renderingContext
     * @return string
     */
    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
    {
        $newRequest = static::getUsedSearchRequestFromRenderingContext($renderingContext)
            ->getCopyForSubRequest()
            ->setRawQueryString(null);
        $uri = self::getSearchUriBuilder($renderingContext)->getCurrentSearchUri($newRequest);
        return $uri;
    }
}

Introduced in solr v11.5 by 61076e3 the method SearchRequest::setRawQueryString(string $rawQueryString = '') enforces a string. Thereby it is no longer possible to set the query-string to null.

ext-solr/Classes/Domain/Search/SearchRequest.php

Lines 436 to 439 in dfcdd98

	/**
	* Method to overwrite the query string.
	*/
	public function setRawQueryString(string $rawQueryString = ''): SearchRequest

Describe the solution you'd like
Introduce a new method that removes the query-string from SearchRequest.

Describe alternatives you've considered
Alternative A:
Allow null as argument for the method:

    public function setRawQueryString(string|null $rawQueryString = ''): SearchRequest

Alternative B:
Set query string to empty string …->setRawQueryString(''):

But this will result in an unnecessary empty query-string in the url:
https://example.com/search/?tx_solr[filter][0]=altType%3ASomeCategory&tx_solr[q]=

Additional context
Completely removing the SearchRequest is afaik only usefull with allowEmptyQuery set in TS-config:

plugin.tx_solr {
  search {
    query {
      allowEmptyQuery = 1
    }
}

Target versions

• 12.0
• 11.5 (TBD)