WP_User_Query::parse_tax_query( array $q )

	protected function parse_tax_query( &$q ) {
		if ( ! empty( $q['tax_query'] ) && is_array( $q['tax_query'] ) ) {
			$tax_query = $q['tax_query'];
		} else {
			$tax_query = array();
		}

		if ( ! empty( $q['taxonomy'] ) && ! empty( $q['term'] ) ) {
			$tax_query[] = array(
				'taxonomy' => $q['taxonomy'],
				'terms'    => array( $q['term'] ),
				'field'    => 'slug',
			);
		}

		foreach ( get_taxonomies( array(), 'objects' ) as $taxonomy => $t ) {
			if ( 'post_tag' == $taxonomy ) {
				continue; // Handled further down in the $q['tag'] block.
			}

			if ( $t->query_var && ! empty( $q[ $t->query_var ] ) ) {
				$tax_query_defaults = array(
					'taxonomy' => $taxonomy,
					'field'    => 'slug',
				);

				if ( isset( $t->rewrite['hierarchical'] ) && $t->rewrite['hierarchical'] ) {
					$q[ $t->query_var ] = wp_basename( $q[ $t->query_var ] );
				}

				$term = $q[ $t->query_var ];

				if ( is_array( $term ) ) {
					$term = implode( ',', $term );
				}

				if ( strpos( $term, '+' ) !== false ) {
					$terms = preg_split( '/[+]+/', $term );
					foreach ( $terms as $term ) {
						$tax_query[] = array_merge(
							$tax_query_defaults,
							array(
								'terms' => array( $term ),
							)
						);
					}
				} else {
					$tax_query[] = array_merge(
						$tax_query_defaults,
						array(
							'terms' => preg_split( '/[,]+/', $term ),
						)
					);
				}
			}
		}

		$this->tax_query = new WP_Tax_Query( $tax_query );

		/**
		 * Fires after taxonomy-related query vars have been parsed.
		 *
		 * @since CP-2.1.0
		 *
		 * @param WP_User_Query $this The WP_User_Query instance.
		 */
		do_action( 'parse_user_tax_query', $this );
	}