Make sure list field |length filter works as expected

src/Entity/Field/CollectionField.php

@@ -10,6 +10,7 @@
 use Bolt\Entity\FieldParentInterface;
 use Bolt\Entity\FieldParentTrait;
 use Bolt\Entity\ListFieldInterface;
+use Bolt\Entity\ListFieldTrait;
 use Bolt\Repository\FieldRepository;
 use Doctrine\ORM\Mapping as ORM;
 
@@ -19,6 +20,7 @@
 class CollectionField extends Field implements FieldInterface, FieldParentInterface, ListFieldInterface
 {
     use FieldParentTrait;
+    use ListFieldTrait;
 
     public const TYPE = 'collection';
 

src/Entity/Field/FileField.php

@@ -58,8 +58,8 @@ public function getValue(): array
      * Allows {% if image is empty %} in Twig
      * See https://twig.symfony.com/doc/3.x/tests/empty.html
      */
-    public function count()
+    public function count(): int
     {
-        return empty($this->getValue()['filename']);
+        return empty($this->getValue()['filename']) ? 0 : 1;
     }
 }

src/Entity/Field/FilelistField.php

@@ -8,13 +8,16 @@
 use Bolt\Entity\Field;
 use Bolt\Entity\FieldInterface;
 use Bolt\Entity\ListFieldInterface;
+use Bolt\Entity\ListFieldTrait;
 use Doctrine\ORM\Mapping as ORM;
 
 /**
  * @ORM\Entity
  */
 class FilelistField extends Field implements FieldInterface, ListFieldInterface
 {
+    use ListFieldTrait;
+
     public const TYPE = 'filelist';
 
     /**

src/Entity/Field/ImageField.php

@@ -105,8 +105,8 @@ public function includeAlt(): bool
      * Allows {% if file is empty %} in Twig
      * See https://twig.symfony.com/doc/3.x/tests/empty.html
      */
-    public function count()
+    public function count(): int
     {
-        return empty($this->getValue()['filename']);
+        return empty($this->getValue()['filename']) ? 0 : 1;
     }
 }

src/Entity/Field/ImagelistField.php

@@ -8,13 +8,16 @@
 use Bolt\Entity\Field;
 use Bolt\Entity\FieldInterface;
 use Bolt\Entity\ListFieldInterface;
+use Bolt\Entity\ListFieldTrait;
 use Doctrine\ORM\Mapping as ORM;
 
 /**
  * @ORM\Entity
  */
 class ImagelistField extends Field implements FieldInterface, ListFieldInterface
 {
+    use ListFieldTrait;
+
     public const TYPE = 'imagelist';
 
     /**

src/Entity/Field/SetField.php

@@ -9,16 +9,19 @@
 use Bolt\Entity\FieldInterface;
 use Bolt\Entity\FieldParentInterface;
 use Bolt\Entity\FieldParentTrait;
+use Bolt\Entity\ListFieldInterface;
+use Bolt\Entity\ListFieldTrait;
 use Bolt\Repository\FieldRepository;
 use Doctrine\ORM\Mapping as ORM;
 use Tightenco\Collect\Support\Collection;
 
 /**
  * @ORM\Entity
  */
-class SetField extends Field implements FieldInterface, FieldParentInterface
+class SetField extends Field implements FieldInterface, FieldParentInterface, ListFieldInterface
 {
     use FieldParentTrait;
+    use ListFieldTrait;
 
     public const TYPE = 'set';
 

src/Entity/ListFieldInterface.php

@@ -7,6 +7,6 @@
 /**
  * Any Field that has an array of fields as its value must implement this interface.
  */
-interface ListFieldInterface
+interface ListFieldInterface extends \Countable
 {
 }

src/Entity/ListFieldTrait.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bolt\Entity;
+
+trait ListFieldTrait
+{
+    /**
+     * Makes ListFieldInterface fields |length filter
+     * return the number of elements in the field
+     */
+    public function count(): int
+    {
+        return count($this->getValue());
+    }
+}