Sitemaps: Improve sitemap.xml redirects when using custom permalinks.

Changes the way redirects from `sitemap.xml` to `wp-sitemap.xml` happen, so that they also work when using a more complex custom rewrite structure.

Props gmariani405, swissspidy, euthelup, peterwilsoncc.
Fixes #61931.

git-svn-id: https://develop.svn.wordpress.org/trunk@59228 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-rewrite.php

@@ -1287,6 +1287,9 @@ public function rewrite_rules() {
 		// favicon.ico -- only if installed at the root.
 		$favicon_rewrite = ( empty( $home_path['path'] ) || '/' === $home_path['path'] ) ? array( 'favicon\.ico$' => $this->index . '?favicon=1' ) : array();
 
+		// sitemap.xml -- only if installed at the root.
+		$sitemap_rewrite = ( empty( $home_path['path'] ) || '/' === $home_path['path'] ) ? array( 'sitemap\.xml' => $this->index . '??sitemap=index' ) : array();
+
 		// Old feed and service files.
 		$deprecated_files = array(
 			'.*wp-(atom|rdf|rss|rss2|feed|commentsrss2)\.php$' => $this->index . '?feed=old',
@@ -1449,9 +1452,9 @@ public function rewrite_rules() {
 
 		// Put them together.
 		if ( $this->use_verbose_page_rules ) {
-			$this->rules = array_merge( $this->extra_rules_top, $robots_rewrite, $favicon_rewrite, $deprecated_files, $registration_pages, $root_rewrite, $comments_rewrite, $search_rewrite, $author_rewrite, $date_rewrite, $page_rewrite, $post_rewrite, $this->extra_rules );
+			$this->rules = array_merge( $this->extra_rules_top, $robots_rewrite, $favicon_rewrite, $sitemap_rewrite, $deprecated_files, $registration_pages, $root_rewrite, $comments_rewrite, $search_rewrite, $author_rewrite, $date_rewrite, $page_rewrite, $post_rewrite, $this->extra_rules );
 		} else {
-			$this->rules = array_merge( $this->extra_rules_top, $robots_rewrite, $favicon_rewrite, $deprecated_files, $registration_pages, $root_rewrite, $comments_rewrite, $search_rewrite, $author_rewrite, $date_rewrite, $post_rewrite, $page_rewrite, $this->extra_rules );
+			$this->rules = array_merge( $this->extra_rules_top, $robots_rewrite, $favicon_rewrite, $sitemap_rewrite, $deprecated_files, $registration_pages, $root_rewrite, $comments_rewrite, $search_rewrite, $author_rewrite, $date_rewrite, $post_rewrite, $page_rewrite, $this->extra_rules );
 		}
 
 		/**

src/wp-includes/sitemaps/class-wp-sitemaps.php

@@ -75,7 +75,6 @@ public function init() {
 		$this->register_sitemaps();
 
 		// Add additional action callbacks.
-		add_filter( 'pre_handle_404', array( $this, 'redirect_sitemapxml' ), 10, 2 );
 		add_filter( 'robots_txt', array( $this, 'add_robots' ), 0, 2 );
 	}
 
@@ -223,6 +222,7 @@ public function render_sitemaps() {
 	 * Redirects a URL to the wp-sitemap.xml
 	 *
 	 * @since 5.5.0
+	 * @deprecated 6.7.0 Deprecated in favor of {@see WP_Rewrite::rewrite_rules()}
 	 *
 	 * @param bool     $bypass Pass-through of the pre_handle_404 filter value.
 	 * @param WP_Query $query  The WP_Query object.

tests/phpunit/tests/canonical/sitemaps.php

@@ -51,6 +51,17 @@ public function test_sitemaps_canonical_pretty_redirects( $test_url, $expected )
 		$this->assertCanonical( $test_url, $expected, 50910 );
 	}
 
+	/**
+	 * Ensure sitemaps redirects work as expected with a more custom rewrite structure.
+	 *
+	 * @dataProvider data_sitemaps_canonical_pretty_redirects
+	 * @ticket 61931
+	 */
+	public function test_sitemaps_canonical_custom_pretty_redirects( $test_url, $expected ) {
+		$this->set_permalink_structure( '/%category%/%year%/%monthnum%/%postname%/' );
+		$this->assertCanonical( $test_url, $expected, 61931 );
+	}
+
 	/**
 	 * Data provider for test_sitemaps_canonical_pretty_redirects.
 	 *
@@ -61,8 +72,12 @@ public function test_sitemaps_canonical_pretty_redirects( $test_url, $expected )
 	 *     @type string $1 The expected canonical URL.
 	 * }
 	 */
-	public function data_sitemaps_canonical_pretty_redirects() {
+	public static function data_sitemaps_canonical_pretty_redirects() {
 		return array(
+			// sitemap.xml special case.
+			array( '/sitemap.xml', '/wp-sitemap.xml' ),
+			array( '/sitemap.xml/', '/wp-sitemap.xml' ),
+
 			// Ugly/incorrect versions redirect correctly.
 			array( '/?sitemap=index', '/wp-sitemap.xml' ),
 			array( '/wp-sitemap.xml/', '/wp-sitemap.xml' ),