Expand image for {attachment slug link=self}

Clicking on the image will no longer open it directly, but expand it
instead.

src/scripts/tutti/8_expand_image.js

@@ -1,8 +1,6 @@
 $(function() {
-    /* Expand images when their link points to a jpg/png/gif/webp */
+
-    var imgs = $('.expand-image-links a img')
+    function _expandImg(e) {
-    .off('click')
-    .on('click', function(e){
         var $img = $(this);
         var href = $img.parent().attr('href');
 
@@ -14,5 +12,15 @@ $(function() {
                         .html(overlay_img);
             e.preventDefault();
         }
-    });
+    }
+
+    $.fn.expandOnClick = function() {
+        $(this)
+            .off('click')
+            .on('click', _expandImg);
+    };
+
+    /* Expand images when their link points to a jpg/png/gif/webp */
+    $('.expand-image-links a img').expandOnClick();
+    $('a.expand-image-links img').expandOnClick();
 });

src/templates/nodes/attachments/file_image.pug

@@ -1,6 +1,6 @@
 | {% if 'link' in tag_args and tag_args['link'] != 'none' %}
 |     {% if tag_args['link'] == 'self' %}
-a(href="{{ vars['l'].link }}")
+a.expand-image-links(href="{{ vars['l'].link }}")
 	img(src="{{ vars['l'].link }}", alt="{{ file.filename }}")
 |     {% else %}
 a(href="{{ tag_args['link'] }}", target="_blank")

tests/test_shortcodes.py

@@ -185,12 +185,14 @@ class AttachmentTest(AbstractPillarTest):
         link = db_file['variations'][0]['link']
 
         with self.app.test_request_context():
+            self_linked = f'<a class="expand-image-links" href="{link}">' \
+                          f'<img src="{link}" alt="cute_kitten.jpg"/></a>'
             self.assertEqual(
-                f'<a href="{link}"><img src="{link}" alt="cute_kitten.jpg"/></a>',
+                self_linked,
                 render('{attachment img link}', context=node_props).strip()
             )
             self.assertEqual(
-                f'<a href="{link}"><img src="{link}" alt="cute_kitten.jpg"/></a>',
+                self_linked,
                 render('{attachment img link=self}', context=node_props).strip()
             )
             self.assertEqual(