Issue #3000677 by catch, Shane Birley, featherbelly, alexpott, larowlan: Fatal error after upgrade to 8.6x [due to regression in extension system]

Author: larowlan

lib/Drupal/Core/Extension/ModuleHandler.php

@@ -777,7 +777,12 @@ public function getModuleDirectories() {
    * {@inheritdoc}
    */
   public function getName($module) {
-    return \Drupal::service('extension.list.module')->getName($module);
+    try {
+      return \Drupal::service('extension.list.module')->getName($module);
+    }
+    catch (UnknownExtensionException $e) {
+      return $module;
+    }
   }
 
 }

tests/Drupal/KernelTests/Core/Extension/ModuleHandlerTest.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Drupal\KernelTests\Core\Extension;
+
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * @coversDefaultClass \Drupal\Core\Extension\ModuleHandler
+ *
+ * @group Extension
+ */
+class ModuleHandlerTest extends KernelTestBase {
+
+  /**
+   * Tests requesting the name of an invalid module.
+   *
+   * @covers ::getName
+   */
+  public function testInvalidGetName() {
+    $module_handler = $this->container->get('module_handler');
+    $this->assertSame('module_nonsense', $module_handler->getName('module_nonsense'));
+  }
+
+}