add whenFilled() api resource helper

Author: ziadoz

src/Illuminate/Http/Resources/ConditionallyLoadsAttributes.php

@@ -227,6 +227,20 @@ protected function whenNotNull($value, $default = new MissingValue)
         return $this->when(! is_null($value), ...$arguments);
     }
 
+    /**
+     * Retrieve a model attribute if it is filled.
+     *
+     * @param  mixed  $value
+     * @param  mixed  $default
+     * @return \Illuminate\Http\Resources\MissingValue|mixed
+     */
+    protected function whenFilled($value, $default = new MissingValue)
+    {
+        $arguments = func_num_args() == 1 ? [$value] : [$value, $default];
+
+        return $this->when(filled($value), ...$arguments);
+    }
+
     /**
      * Retrieve an accessor when it has been appended.
      *

tests/Integration/Http/Fixtures/PostResourceWithOptionalFilledAttributes.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Http\Fixtures;
+
+use Illuminate\Http\Resources\Json\JsonResource;
+
+class PostResourceWithOptionalFilledAttributes extends JsonResource
+{
+    public function toArray($request)
+    {
+        return [
+            'id' => $this->whenFilled($this->id, 42),
+            'title' => $this->whenFilled($this->title, 'no title'),
+        ];
+    }
+}

tests/Integration/Http/ResourceTest.php

@@ -31,6 +31,7 @@
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalAppendedAttributes;
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalAttributes;
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalData;
+use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalFilledAttributes;
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalHasAttributes;
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalMerging;
 use Illuminate\Tests\Integration\Http\Fixtures\PostResourceWithOptionalPivotRelationship;
@@ -217,6 +218,29 @@ public function testResourcesMayHaveOptionalSelectedAttributes()
         ]);
     }
 
+    public function testResourcesMayHaveOptionalFilledAttributes()
+    {
+        Route::get('/', function () {
+            return new PostResourceWithOptionalFilledAttributes(new Post([
+                'id' => 5,
+                'title' => '',
+            ]));
+        });
+
+        $response = $this->withoutExceptionHandling()->get(
+            '/', ['Accept' => 'application/json']
+        );
+
+        $response->assertStatus(200);
+
+        $response->assertJson([
+            'data' => [
+                'id' => 5,
+                'title' => 'no title',
+            ],
+        ]);
+    }
+
     public function testResourcesMayHaveOptionalHasAttributes()
     {
         Route::get('/', function () {