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function is not described

wp_widget_rss_process() WP 2.5.0

Process RSS feed widget data and optionally retrieve feed items.

The feed widget can not have more than 20 items or it will reset back to the default, which is 10.

The resulting array has the feed title, feed url, feed link (from channel), feed items, error (if any), and whether to show summary, author, and date. All respectively in the order of the array elements.

No Hooks.

Return

Array.

Usage

wp_widget_rss_process( $widget_rss, $check_feed );
$widget_rss(array) (required)
RSS widget feed data. Expects unescaped data.
$check_feed(true/false)
Whether to check feed for errors.
Default: true

Code of wp widget rss process: wp-includes/widgets.php WP 5.2.1

<?php
function wp_widget_rss_process( $widget_rss, $check_feed = true ) {
	$items = (int) $widget_rss['items'];
	if ( $items < 1 || 20 < $items ) {
		$items = 10;
	}
	$url          = esc_url_raw( strip_tags( $widget_rss['url'] ) );
	$title        = isset( $widget_rss['title'] ) ? trim( strip_tags( $widget_rss['title'] ) ) : '';
	$show_summary = isset( $widget_rss['show_summary'] ) ? (int) $widget_rss['show_summary'] : 0;
	$show_author  = isset( $widget_rss['show_author'] ) ? (int) $widget_rss['show_author'] : 0;
	$show_date    = isset( $widget_rss['show_date'] ) ? (int) $widget_rss['show_date'] : 0;

	if ( $check_feed ) {
		$rss   = fetch_feed( $url );
		$error = false;
		$link  = '';
		if ( is_wp_error( $rss ) ) {
			$error = $rss->get_error_message();
		} else {
			$link = esc_url( strip_tags( $rss->get_permalink() ) );
			while ( stristr( $link, 'http' ) != $link ) {
				$link = substr( $link, 1 );
			}

			$rss->__destruct();
			unset( $rss );
		}
	}

	return compact( 'title', 'url', 'link', 'items', 'error', 'show_summary', 'show_author', 'show_date' );
}