fix: Default x and y to 0 in ImageRenderer (#206)

Fixes #189

src/Rasterization/Renderers/ImageRenderer.php

@@ -25,12 +25,17 @@ public function render(SVGRasterizer $rasterizer, array $options, SVGNode $conte
     {
         $transform = $rasterizer->getCurrentTransform();
 
-        $x      = $options['x'];
-        $y      = $options['y'];
+        $x      = $options['x'] ?? 0;
+        $y      = $options['y'] ?? 0;
         $transform->map($x, $y);
 
-        $width  = $options['width'];
-        $height = $options['height'];
+        // TODO support "auto" values for width and height
+
+        $width  = $options['width'] ?? 0;
+        $height = $options['height'] ?? 0;
+        if ($width <= 0 || $height <= 0) {
+            return;
+        }
         $transform->resize($width, $height);
 
         $image = $rasterizer->getImage();

tests/Rasterization/Renderers/ImageRendererTest.php

@@ -2,8 +2,10 @@
 
 namespace SVG;
 
+use AssertGD\GDSimilarityConstraint;
 use SVG\Rasterization\Renderers\ImageRenderer;
 use SVG\Nodes\SVGNode;
+use SVG\Rasterization\SVGRasterizer;
 
 class SVGNodeClass extends SVGNode
 {
@@ -27,17 +29,39 @@ class ImageRendererTest extends \PHPUnit\Framework\TestCase
 {
     public function testRender()
     {
-        $rast = new \SVG\Rasterization\SVGRasterizer(10, 20, null, 100, 200);
-        $options = [
-            'href'   => __DIR__ . '/../../sample.svg',
-            'x'      => 10.5,
-            'y'      => 10.5,
-            'width'  => 100.5,
-            'height' => 100.5
-        ];
-        $svgImageRender = new ImageRenderer();
+        $obj = new ImageRenderer();
+
         $context = new SVGNodeClass();
 
-        $this->assertNull($svgImageRender->render($rast, $options, $context));
+        $rasterizer = new SVGRasterizer(10, 10, null, 100, 100);
+        $obj->render($rasterizer, [
+            'href'   => __DIR__ . '/../../squares.svg',
+            'x'      => 1,
+            'y'      => 2,
+            'width'  => 6,
+            'height' => 6
+        ], $context);
+        $img = $rasterizer->finish();
+
+        $this->assertThat($img, new GDSimilarityConstraint('./tests/images/renderer-image.png'));
+    }
+
+    public function testDefaultsXAndYToZero()
+    {
+        $obj = new ImageRenderer();
+
+        $context = new SVGNodeClass();
+
+        $rasterizer = new SVGRasterizer('10px', '10px', null, 100, 100);
+        $obj->render($rasterizer, [
+            'href'   => __DIR__ . '/../../squares.svg',
+            'x'      => null,
+            'y'      => null,
+            'width'  => 6,
+            'height' => 6
+        ], $context);
+        $img = $rasterizer->finish();
+
+        $this->assertThat($img, new GDSimilarityConstraint('./tests/images/renderer-image-x0y0.png'));
     }
 }