fix(starter-content): restore featured images on generated posts

plugins/newspack-plugin/includes/starter_content/class-starter-content-generated.php

@@ -539,14 +539,19 @@ private static function download_random_image() {
 			return null;
 		}
 
+		// wp_handle_sideload() takes $file by reference and writes back into it, so the
+		// array has to be a variable. Passing the literal is a fatal on PHP 8, which took
+		// down every non-E2E starter-content post before it could get a featured image.
+		$file = [
+			'name'     => 'automated_upload.jpg',
+			'type'     => mime_content_type( $temp_file ),
+			'tmp_name' => $temp_file,
+			'error'    => 0,
+			'size'     => filesize( $temp_file ),
+		];
+
 		$file_attributes = wp_handle_sideload(
-			[
-				'name'     => 'automated_upload.jpg',
-				'type'     => mime_content_type( $temp_file ),
-				'tmp_name' => $temp_file,
-				'error'    => 0,
-				'size'     => filesize( $temp_file ),
-			],
+			$file,
 			[
 				'test_form'   => false,
 				'test_size'   => true,

plugins/newspack-plugin/tests/unit-tests/starter-content-generated.php

@@ -0,0 +1,113 @@
+<?php
+/**
+ * Tests generated starter content.
+ *
+ * @package Newspack\Tests
+ */
+
+use Newspack\Starter_Content_Generated;
+
+/**
+ * Tests generated starter content.
+ */
+class Newspack_Test_Starter_Content_Generated extends WP_UnitTestCase {
+
+	/**
+	 * Files written into the uploads directory by a test, removed afterwards.
+	 *
+	 * @var string[]
+	 */
+	private $written_files = [];
+
+	/**
+	 * Filters this test added, removed individually in tear_down().
+	 *
+	 * Removing them by name rather than clearing the hook: the WordPress test suite
+	 * installs its own pre_http_request handlers, and remove_all_filters() takes those
+	 * with it and breaks every later test that makes a request.
+	 *
+	 * @var callable[]
+	 */
+	private $http_filters = [];
+
+	public function tear_down() { // phpcs:ignore Squiz.Commenting.FunctionComment.Missing
+		foreach ( $this->written_files as $file ) {
+			if ( file_exists( $file ) ) {
+				unlink( $file ); // phpcs:ignore WordPressVIPMinimum.Functions.RestrictedFunctions.file_ops_unlink
+			}
+		}
+		$this->written_files = [];
+		foreach ( $this->http_filters as $filter ) {
+			remove_filter( 'pre_http_request', $filter, 10 );
+		}
+		$this->http_filters = [];
+		parent::tear_down();
+	}
+
+	/**
+	 * Serve the bundled starter image instead of reaching the image host, writing it to
+	 * the stream target download_url() passes so the sideload sees a real file.
+	 */
+	private function stub_image_download() {
+		$filter = function ( $pre, $args, $url ) {
+			if ( false === strpos( $url, 'picsum.photos' ) ) {
+				return $pre;
+			}
+			if ( ! empty( $args['filename'] ) ) {
+				copy( NEWSPACK_ABSPATH . 'includes/raw_assets/images/starter-content-featured-image.jpg', $args['filename'] );
+			}
+			return [
+				'response' => [
+					'code'    => 200,
+					'message' => 'OK',
+				],
+				'headers'  => [],
+				'body'     => '',
+				'cookies'  => [],
+				'filename' => $args['filename'] ?? null,
+			];
+		};
+
+		$this->http_filters[] = $filter;
+		add_filter( 'pre_http_request', $filter, 10, 3 );
+	}
+
+	/**
+	 * The image sideload lands a file in the uploads directory.
+	 *
+	 * Passing the sideload array inline is a fatal on PHP 8 rather than a failed upload,
+	 * because wp_handle_sideload() takes its first argument by reference. Every
+	 * starter-content post outside E2E died there before it could get a featured image.
+	 */
+	public function test_download_random_image_sideloads_into_uploads() {
+		$this->stub_image_download();
+
+		$method = new ReflectionMethod( Starter_Content_Generated::class, 'download_random_image' );
+		$method->setAccessible( true );
+		$path = $method->invoke( null );
+
+		$this->assertIsString( $path, 'The sideload returns a path rather than failing.' );
+		$this->written_files[] = $path;
+
+		$this->assertFileExists( $path, 'The sideloaded file is on disk.' );
+		$uploads = wp_upload_dir();
+		$this->assertStringStartsWith( $uploads['basedir'], $path, 'The file landed in the uploads directory.' );
+		$this->assertGreaterThan( 0, filesize( $path ), 'The sideloaded file has content.' );
+	}
+
+	/**
+	 * A failed download is reported as no image, not as a fatal.
+	 */
+	public function test_download_random_image_returns_null_when_the_request_fails() {
+		$filter = function () {
+			return new WP_Error( 'http_request_failed', 'Offline.' );
+		};
+		$this->http_filters[] = $filter;
+		add_filter( 'pre_http_request', $filter, 10, 3 );
+
+		$method = new ReflectionMethod( Starter_Content_Generated::class, 'download_random_image' );
+		$method->setAccessible( true );
+
+		$this->assertNull( $method->invoke( null ), 'An unreachable image host yields no image.' );
+	}
+}