`WP_Query::parse_tax_query()` has always been documented as `protected`. Plugins should never have used it. However, it did not have a `protected` access modifier, so its visibility was `public` by default. If the access modifier had been present, accessing the method in a plugin would have produced a fatal error. The access modifier was added in [28523], along with magic methods to allow it to be accessed for BC. This one method is problematic because it expects to be passed a reference. The `WP_Query::__call()` logic does not go out of its way to fix this signature discrepancy, and so a warning is thrown: `Parameter 1 to WP_Query::parse_tax_query() expected to be a reference, value given`.

Remove the `protected` access modifier from `WP_Query::parse_tax_query()`.

Fixes #28739.


git-svn-id: https://develop.svn.wordpress.org/trunk@28987 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/query.php

@@ -1822,7 +1822,7 @@ class WP_Query {
 	 *
 	 * @param array &$q The query variables
 	 */
-	protected function parse_tax_query( &$q ) {
+	function parse_tax_query( &$q ) {
 		if ( ! empty( $q['tax_query'] ) && is_array( $q['tax_query'] ) ) {
 			$tax_query = $q['tax_query'];
 		} else {