Allow provided layout to override default parameters in layout

Fixes an issue where a default parameter is provided via default layout
but was not overriden when $providedLayout is provided.

Author: dennis-fedco

src/ZendViewRenderer.php

@@ -342,7 +342,7 @@ private function prepareLayout(ModelInterface $viewModel)
         if ($layout) {
             $layout->addChild($viewModel);
             $viewModel = $layout;
-            $viewModel->setVariables($this->mergeParams($layout->getTemplate(), []));
+            $viewModel->setVariables($this->mergeParams($layout->getTemplate(), (array) $layout->getVariables()));
         }
 
         return $viewModel;

test/ZendViewRendererTest.php

@@ -268,6 +268,32 @@ public function testTemplateDefaultParameterIsAvailableInLayout()
         $this->assertContains($expected, $result, sprintf('Received %s', $result));
     }
 
+    public function testTemplateDefaultParameterIsAvailableInProvidedLayout()
+    {
+        $renderer = new ZendViewRenderer(null);
+        $renderer->addPath(__DIR__ . '/TestAsset');
+        $titleToBeOverriden = uniqid('ZendViewTitleToBeOverriden', true);
+        $title = uniqid('ZendViewTitle', true);
+        $name = uniqid('ZendViewName', true);
+        $renderer->addDefaultParam('zendview-layout-variable', 'title', $titleToBeOverriden);
+
+        $layout = new ViewModel(['title' => $title]);
+        $layout->setTemplate('zendview-layout-variable');
+        $result = $renderer->render('zendview', ['name' => $name, 'layout' => $layout]);
+        $this->assertContains($title, $result);
+        $this->assertContains($name, $result);
+
+        $content = file_get_contents(__DIR__ . '/TestAsset/zendview.phtml');
+        $content = str_replace('<?php echo $name ?>', $name, $content);
+        $layout = file_get_contents(__DIR__ . '/TestAsset/zendview-layout-variable.phtml');
+        $layout = str_replace('<?= $this->title ?>', $title, $layout);
+        $layout = str_replace('<?= $this->content ?>' . PHP_EOL, $content, $layout);
+        $this->assertContains($layout, $result);
+
+        $expected = sprintf('<title>Layout Page: %s</title>', $title);
+        $this->assertContains($expected, $result, sprintf('Received %s', $result));
+    }
+
     /**
      * @group layout
      */