Fix bug & add tests

src/Drivers/AbstractDecoder.php

@@ -86,7 +86,7 @@ abstract class AbstractDecoder extends DriverSpecialized implements DecoderInter
                 default => $this->buildFilePointer($path_or_data), // data
             };
 
-            // extract exif data via file path
+            // extract exif data
             $data = @exif_read_data($source, null, true);
             if (is_resource($source)) {
                 fclose($source);

src/Drivers/Gd/Decoders/Traits/CanDecodeGif.php

@@ -41,6 +41,12 @@ trait CanDecodeGif
             );
         }
 
-        return new Image(new Driver(), $core);
+        // create image
+        $image = new Image(new Driver(), $core);
+
+        // set media type
+        $image->origin()->setMediaType('image/gif');
+
+        return $image;
     }
 }

tests/Drivers/Gd/Traits/CanDecodeGifTest.php

@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Intervention\Image\Tests\Drivers\Gd\Traits;
+
+use Intervention\Image\Drivers\Gd\Decoders\Traits\CanDecodeGif;
+use Intervention\Image\Interfaces\ImageInterface;
+use Intervention\Image\Tests\TestCase;
+use Mockery;
+
+class CanDecodeGifTest extends TestCase
+{
+    public function testDecodeGifFromBinaryAnimation(): void
+    {
+        $decoder = Mockery::mock(new class () {
+            use CanDecodeGif;
+        })->makePartial();
+
+        $result = $decoder->decodeGif($this->getTestImageData('animation.gif'));
+        $this->assertInstanceOf(ImageInterface::class, $result);
+        $this->assertEquals('image/gif', $result->origin()->mediaType());
+    }
+
+    public function testDecodeGifFromBinaryStatic(): void
+    {
+        $decoder = Mockery::mock(new class () {
+            use CanDecodeGif;
+        })->makePartial();
+
+        $result = $decoder->decodeGif($this->getTestImageData('red.gif'));
+        $this->assertInstanceOf(ImageInterface::class, $result);
+        $this->assertEquals('image/gif', $result->origin()->mediaType());
+    }
+
+    public function testDecodeGifFromPathAnimation(): void
+    {
+        $decoder = Mockery::mock(new class () {
+            use CanDecodeGif;
+        })->makePartial();
+
+        $result = $decoder->decodeGif($this->getTestImagePath('animation.gif'));
+        $this->assertInstanceOf(ImageInterface::class, $result);
+        $this->assertEquals('image/gif', $result->origin()->mediaType());
+    }
+
+    public function testDecodeGifFromPathStatic(): void
+    {
+        $decoder = Mockery::mock(new class () {
+            use CanDecodeGif;
+        })->makePartial();
+
+        $result = $decoder->decodeGif($this->getTestImagePath('red.gif'));
+        $this->assertInstanceOf(ImageInterface::class, $result);
+        $this->assertEquals('image/gif', $result->origin()->mediaType());
+    }
+}