Add fallback thumbnails for posts without images on front page

src/thumbnails.js

@@ -36,11 +36,21 @@ function has_thumbnail(post) {
 
 async function thumbnail_for_post(post) {
     const thumbnailUrl = getPostThumbnailPath(post);
+    let imageSrc;
+
     if(thumbnailUrl == undefined) {
-        return "";
+        // Use favicon.png as fallback when no thumbnail is defined
+        imageSrc = "favicon.png";
+    } else {
+        imageSrc = stripLeadingSlash(thumbnailUrl);
+        if ( !fs.existsSync(imageSrc)) {
+            // Use favicon.png as fallback when thumbnail file doesn't exist
+            imageSrc = "favicon.png";
+        }
     }
-    const imageSrc = stripLeadingSlash(thumbnailUrl);
+
     if ( !fs.existsSync(imageSrc)) {
+        // If even favicon.png doesn't exist, return empty (shouldn't happen)
         return "";
     } else {
         // console.log("Generating thumbnail for " + imageSrc);

tests/staging/features/recent-posts-thumbnails.feature

@@ -0,0 +1,7 @@
+Feature: Recent Posts Thumbnails
+
+  Scenario: All recent posts should have thumbnail images
+    Given the Staging site is started
+    When the index page is visited
+    Then the recent posts list should be present
+    And each recent post should have a picture tag with an img element

tests/staging/step_definitions/website_steps.js

@@ -76,3 +76,53 @@ Then('the Logo should be displayed in the top left corner', async function () {
     throw new Error('Logo (favicon.png) is not displayed in a nav element');
   }
 });
+
+Then('the recent posts list should be present', async function () {
+  if (!page) {
+    throw new Error('Page not initialized. Make sure previous steps are executed first.');
+  }
+
+  // Check that the recent posts section exists with its heading
+  try {
+    const recentPostsHeading = await page.locator('h2:has-text("Recent Posts")');
+    await recentPostsHeading.waitFor({ state: 'visible', timeout: 10000 });
+
+    // Check that the posts list exists
+    const postsList = await page.locator('ul.posts');
+    await postsList.waitFor({ state: 'visible', timeout: 10000 });
+  } catch (error) {
+    throw new Error('Recent posts list is not present on the page');
+  }
+});
+
+Then('each recent post should have a picture tag with an img element', async function () {
+  if (!page) {
+    throw new Error('Page not initialized. Make sure previous steps are executed first.');
+  }
+
+  // Find all post items in the recent posts list
+  const postItems = await page.locator('ul.posts li.post').all();
+
+  if (postItems.length === 0) {
+    throw new Error('No recent posts found in the posts list');
+  }
+
+  // Check each post item has a picture tag with img element
+  for (let i = 0; i < postItems.length; i++) {
+    const postItem = postItems[i];
+
+    try {
+      // Look for either a picture tag with img, or just an img tag within the media-left link
+      const imageElement = await postItem.locator('a.media-left picture img, a.media-left img').first();
+      await imageElement.waitFor({ state: 'visible', timeout: 5000 });
+
+      // Verify the img element has a valid src attribute
+      const src = await imageElement.getAttribute('src');
+      if (!src || src.trim() === '') {
+        throw new Error(`Post ${i + 1} has an img element but no src attribute`);
+      }
+    } catch (error) {
+      throw new Error(`Post ${i + 1} does not have a picture tag with img element: ${error.message}`);
+    }
+  }
+});