Ensured that the last modification date from the jetpack_page_sitema…

…p_other_urls filter is considered for the last modification date of the generated sitemap. (#36991)

projects/plugins/jetpack/changelog/sitemap-consider-other-urls-lastmod

@@ -0,0 +1,4 @@
+Significance: patch
+Type: other
+
+Sitemaps: Ensured that the last modification date from the jetpack_page_sitemap_other_urls filter is considered for the last modification date of the generated sitemap.

projects/plugins/jetpack/modules/sitemaps/sitemap-builder.php

@@ -686,6 +686,9 @@ public function build_one_page_sitemap( $number, $from_id ) {
 
 					if ( true === $buffer->append( $item['xml'] ) ) {
 						$last_post_id = -$index;
+						if ( isset( $url['lastmod'] ) ) {
+							$buffer->view_time( jp_sitemap_datetime( $url['lastmod'] ) );
+						}
 					} else {
 						break;
 					}

projects/plugins/jetpack/tests/php/modules/sitemaps/test-class.sitemap-builder.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * Tests for the Jetpack_Sitemap_Builder class.
+ *
+ * @package automattic/jetpack
+ * @since $$next-version$$
+ */
+
+/**
+ * Test class for Jetpack_Sitemap_Builder.
+ *
+ * @since $$next-version$$
+ */
+class WP_Test_Jetpack_Sitemap_Builder extends WP_UnitTestCase {
+
+	/**
+	 * "lastmod" date from other URLs filter is considered when building a sitemap.
+	 *
+	 * @covers Jetpack_Sitemap_Builder::build_one_page_sitemap
+	 * @group jetpack-sitemap
+	 * @since $$next-version$$
+	 */
+	public function test_build_one_page_sitemap_considers_lastmod_from_other_urls() {
+		$other_urls = array(
+			array(
+				'loc'     => 'https://example.com/1',
+				'lastmod' => '2019-01-01T00:00:00Z',
+			),
+			array(
+				'loc'     => 'https://example.com/2',
+				'lastmod' => '2024-03-08T01:02:03Z',
+			),
+			array(
+				'loc'     => 'https://example.com/3',
+				'lastmod' => '2022-02-02T00:00:00Z',
+			),
+		);
+
+		$callback = function () use ( $other_urls ) {
+			return $other_urls;
+		};
+
+		add_filter( 'jetpack_page_sitemap_other_urls', $callback );
+
+		$builder = new Jetpack_Sitemap_Builder();
+		$result  = $builder->build_one_page_sitemap( 1, 1 );
+
+		remove_filter( 'jetpack_page_sitemap_other_urls', $callback );
+
+		$this->assertSame( '2024-03-08T01:02:03Z', $result['last_modified'], 'Last modified date is not the one from the other_urls filter.' );
+	}
+}