Ensure that post thumbnail is cached in latest post block.

packages/block-library/src/latest-posts/index.php

@@ -37,11 +37,12 @@ function render_block_core_latest_posts( $attributes ) {
 	global $post, $block_core_latest_posts_excerpt_length;
 
 	$args = array(
-		'posts_per_page'   => $attributes['postsToShow'],
-		'post_status'      => 'publish',
-		'order'            => $attributes['order'],
-		'orderby'          => $attributes['orderBy'],
-		'suppress_filters' => false,
+		'posts_per_page'      => $attributes['postsToShow'],
+		'post_status'         => 'publish',
+		'order'               => $attributes['order'],
+		'orderby'             => $attributes['orderBy'],
+		'ignore_sticky_posts' => true,
+		'no_found_rows'       => true,
 	);
 
 	$block_core_latest_posts_excerpt_length = $attributes['excerptLength'];
@@ -54,7 +55,12 @@ function render_block_core_latest_posts( $attributes ) {
 		$args['author'] = $attributes['selectedAuthor'];
 	}
 
-	$recent_posts = get_posts( $args );
+	$query        = new WP_Query;
+	$recent_posts = $query->query( $args );
+
+	if ( isset( $attributes['displayFeaturedImage'] ) && $attributes['displayFeaturedImage'] ) {
+		update_post_thumbnail_cache( $query );
+	}
 
 	$list_items_markup = '';
 

phpunit/blocks/render-last-posts-test.php

@@ -0,0 +1,79 @@
+<?php
+/**
+ * Last post block rendering tests.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ */
+
+/**
+ * Tests for the Last post block.
+ *
+ * @group blocks
+ */
+class Tests_Blocks_RenderLastPosts extends WP_UnitTestCase {
+	protected static $post;
+	protected static $sticky_post;
+	protected static $attachment_id;
+
+	public static function wpSetUpBeforeClass( WP_UnitTest_Factory $factory ) {
+		self::$sticky_post = $factory->post->create_and_get(
+			array(
+				'post_title' => 'Sticky post',
+				'post_date'  => '2008-09-03 00:00:00',
+			)
+		);
+		$factory->post->create_many( 2 );
+		self::$post = $factory->post->create_and_get();
+
+		stick_post( self::$sticky_post->ID );
+
+		$file                = DIR_TESTDATA . '/images/canola.jpg';
+		self::$attachment_id = $factory->attachment->create_upload_object( $file, self::$post->ID );
+		set_post_thumbnail( self::$post, self::$attachment_id );
+	}
+
+	public static function tear_down_after_class() {
+		wp_delete_post( self::$attachment_id, true );
+		parent::tear_down_after_class();
+	}
+
+	/**
+	 * @covers render_block_core_latest_posts
+	 */
+	public function test_render_block_core_latest_posts() {
+		$a = new MockAction();
+		add_filter( 'update_post_metadata_cache', array( $a, 'filter' ), 10, 2 );
+		$attributes = array(
+			'displayFeaturedImage' => true,
+			'postsToShow'          => 3,
+			'orderBy'              => 'date',
+			'order'                => 'DESC',
+		);
+
+		render_block_core_latest_posts( $attributes );
+		$args      = $a->get_args();
+		$last_args = end( $args );
+		$this->assertContains( self::$attachment_id, $last_args[1] );
+	}
+
+	/**
+	 * @covers render_block_core_latest_posts
+	 */
+	public function test_render_block_core_latest_posts_no_priming() {
+		$a = new MockAction();
+		add_filter( 'update_post_metadata_cache', array( $a, 'filter' ), 10, 2 );
+		$attributes = array(
+			'displayFeaturedImage' => false,
+			'postsToShow'          => 3,
+			'orderBy'              => 'date',
+			'order'                => 'DESC',
+		);
+
+		render_block_core_latest_posts( $attributes );
+		$args      = $a->get_args();
+		$last_args = end( $args );
+		$this->assertContains( self::$post->ID, $last_args );
+		$this->assertNotContains( self::$sticky_post->ID, $last_args[1] );
+	}
+}