Add tests for image cloning

tests/ImageTest.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace Intervention\Image\Tests;
+
+use Imagick;
+use ImagickPixel;
+use Intervention\Image\Drivers\Gd\Core as GdCore;
+use Intervention\Image\Drivers\Gd\Driver as GdDriver;
+use Intervention\Image\Drivers\Gd\Frame as GdFrame;
+use Intervention\Image\Drivers\Imagick\Core as ImagickCore;
+use Intervention\Image\Drivers\Imagick\Driver as ImagickDriver;
+use Intervention\Image\Image;
+
+class ImageTest extends TestCase
+{
+    public function testCloneImageGd(): void
+    {
+        $image = new Image(
+            new GdDriver(),
+            new GdCore([
+                new GdFrame(imagecreatetruecolor(3, 3))
+            ])
+        );
+
+        $clone = clone $image;
+
+        $this->assertEquals(3, $image->width());
+        $this->assertEquals(3, $clone->width());
+        $result = $clone->resize(1);
+        $this->assertEquals(3, $image->width());
+        $this->assertEquals(1, $clone->width());
+        $this->assertEquals(1, $result->width());
+    }
+
+    public function testCloneImageImagick(): void
+    {
+        $imagick = new Imagick();
+        $imagick->newImage(3, 2, new ImagickPixel('red'), 'png');
+        $image = new Image(
+            new ImagickDriver(),
+            new ImagickCore($imagick)
+        );
+
+        $clone = clone $image;
+
+        $this->assertEquals(3, $image->width());
+        $this->assertEquals(3, $clone->width());
+        $result = $clone->resize(1);
+        $this->assertEquals(3, $image->width());
+        $this->assertEquals(1, $clone->width());
+        $this->assertEquals(1, $result->width());
+    }
+}