Throw exception for invalid template in dev mode

In developer mode php notices/warnings etc are promoted to being exceptions. This means the developer is a bit more diligent with cleaning up any messes as they occur.

I noticed this error on a Magento 1 client which is filled with "Not valid template file", I checked in M2 and this error seems to persist.

This change should make sure developers do not lead any dead templates in their layout.xml.

Author: convenient

lib/internal/Magento/Framework/View/Element/Template.php

@@ -256,10 +256,12 @@ public function fetchView($fileName)
         } else {
             $html = '';
             $templatePath = $fileName ?: $this->getTemplate();
-            $this->_logger->critical(
-                "Invalid template file: '{$templatePath}' in module: '{$this->getModuleName()}'"
-                . " block's name: '{$this->getNameInLayout()}'"
-            );
+            $errorMessage = "Invalid template file: '{$templatePath}' in module: '{$this->getModuleName()}'"
+                . " block's name: '{$this->getNameInLayout()}'";
+            if ($this->_appState->getMode() === \Magento\Framework\App\State::MODE_DEVELOPER) {
+                throw new \InvalidArgumentException($errorMessage);
+            }
+            $this->_logger->critical($errorMessage);
         }
 
         \Magento\Framework\Profiler::stop('TEMPLATE:' . $fileName);

lib/internal/Magento/Framework/View/Test/Unit/Element/TemplateTest.php

@@ -51,6 +51,11 @@ class TemplateTest extends \PHPUnit_Framework_TestCase
      */
     protected $loggerMock;
 
+    /**
+     * @var \Magento\Framework\App\State|\PHPUnit_Framework_MockObject_MockObject
+     */
+    protected $appState;
+
     protected function setUp()
     {
         $this->resolver = $this->getMock(
@@ -90,8 +95,8 @@ protected function setUp()
         $this->loggerMock = $this->getMock(\Psr\Log\LoggerInterface::class);
         $this->templateEngine->expects($this->any())->method('get')->willReturn($this->templateEngine);
 
-        $appState = $this->getMock(\Magento\Framework\App\State::class, ['getAreaCode'], [], '', false);
-        $appState->expects($this->any())->method('getAreaCode')->willReturn('frontend');
+        $this->appState = $this->getMock(\Magento\Framework\App\State::class, ['getAreaCode', 'getMode'], [], '', false);
+        $this->appState->expects($this->any())->method('getAreaCode')->willReturn('frontend');
         $storeManagerMock = $this->getMock(StoreManager::class, [], [], '', false);
         $storeMock = $this->getMock(Store::class, [], [], '', false);
         $storeManagerMock->expects($this->any())
@@ -112,7 +117,7 @@ protected function setUp()
                 'enginePool' => $this->templateEngine,
                 'resolver' => $this->resolver,
                 'validator' => $this->validator,
-                'appState' => $appState,
+                'appState' => $this->appState,
                 'logger' => $this->loggerMock,
                 'storeManager' => $storeManagerMock,
                 'urlBuilder' => $urlBuilderMock,
@@ -165,6 +170,30 @@ public function testFetchViewWithNoFileName()
         $this->assertEquals($output, $this->block->fetchView($template));
     }
 
+    public function testFetchViewWithNoFileNameDeveloperMode()
+    {
+        $template = false;
+        $templatePath = 'wrong_template_path.pthml';
+        $moduleName = 'Acme';
+        $blockName = 'acme_test_module_test_block';
+        $exception = "Invalid template file: '{$templatePath}' in module: '{$moduleName}' block's name: '{$blockName}'";
+        $this->block->setTemplate($templatePath);
+        $this->block->setData('module_name', $moduleName);
+        $this->block->setNameInLayout($blockName);
+        $this->validator->expects($this->once())
+            ->method('isValid')
+            ->with($template)
+            ->willReturn(false);
+        $this->loggerMock->expects($this->never())
+            ->method('critical');
+        $this->appState->expects($this->once())
+            ->method('getMode')
+            ->willReturn(\Magento\Framework\App\State::MODE_DEVELOPER);
+
+        $this->setExpectedException('\InvalidArgumentException', $exception);
+        $this->block->fetchView($template);
+    }
+
     public function testSetTemplateContext()
     {
         $template = 'themedir/template.phtml';