Issue #2474363 by Aki Tendo, alexpott, Dom., MattA, dawehner, TR, hass, Wim Leers, cburschka, Berdir: Stuck in failed module install process

core/modules/system/src/Form/ModulesUninstallForm.php

@@ -84,7 +84,7 @@ class ModulesUninstallForm extends FormBase {
     // Get a list of all available modules.
     $modules = system_rebuild_module_data();
     $uninstallable = array_filter($modules, function ($module) use ($modules) {
-      return empty($modules[$module->getName()]->info['required']) && drupal_get_installed_schema_version($module->getName()) > SCHEMA_UNINSTALLED;
+      return empty($modules[$module->getName()]->info['required']) && $module->status;
     });
 
     // Include system.admin.inc so we can use the sort callbacks.

core/modules/system/src/Tests/Module/UninstallTest.php

@@ -9,6 +9,7 @@ namespace Drupal\system\Tests\Module;
 
 use Drupal\Core\Cache\Cache;
 use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Entity\EntityMalformedException;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -117,4 +118,31 @@ class UninstallTest extends WebTestBase {
     $this->assertUrl('admin/modules/uninstall');
     $this->assertTitle(t('Uninstall') . ' | Drupal');
   }
+
+  /**
+   * Tests that a module which fails to install can still be uninstalled.
+   */
+  public function testFailedInstallStatus() {
+    $account = $this->drupalCreateUser(array('administer modules'));
+    $this->drupalLogin($account);
+
+    $message = 'Exception thrown when installing module_installer_config_test with an invalid configuration file.';
+    try {
+      $this->container->get('module_installer')->install(array('module_installer_config_test'));
+      $this->fail($message);
+    } catch (EntityMalformedException $e) {
+      $this->pass($message);
+    }
+
+    // Even though the module failed to install properly, its configuration
+    // status is "enabled" and should still be available to uninstall.
+    $this->drupalGet('admin/modules/uninstall');
+    $this->assertText('Module installer config test');
+    $edit['uninstall[module_installer_config_test]'] = TRUE;
+    $this->drupalPostForm('admin/modules/uninstall', $edit, t('Uninstall'));
+    $this->drupalPostForm(NULL, NULL, t('Uninstall'));
+    $this->assertText(t('The selected modules have been uninstalled.'));
+    $this->assertNoText('Module installer config test');
+  }
+
 }

core/modules/system/tests/modules/module_installer_config_test/config/install/module_installer_config_test.type.missing_id.yml

@@ -0,0 +1,3 @@
+# This entity is intentionally missing an 'id' key. During installation, an
+# EntityMalformedException should be thrown about the missing key.
+name: 'This entity does not have an ID'

core/modules/system/tests/modules/module_installer_config_test/config/schema/module_installer_config_test.schema.yml

@@ -0,0 +1,10 @@
+module_installer_config_test.type.*:
+  type: config_entity
+  label: 'Test entity type'
+  mapping:
+    id:
+      type: string
+    name:
+      type: label
+      label: 'Name'
+

core/modules/system/tests/modules/module_installer_config_test/module_installer_config_test.info.yml

@@ -0,0 +1,7 @@
+name: 'Module installer config test'
+description: 'Support module for tests that require a failed module install.'
+type: module
+package: Testing
+core: 8.x
+version: VERSION
+

core/modules/system/tests/modules/module_installer_config_test/src/Entity/TestConfigType.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\module_installer_config_test\Entity\TestConfigType.
+ */
+
+namespace Drupal\module_installer_config_test\Entity;
+
+use Drupal\Core\Config\Entity\ConfigEntityBase;
+
+/**
+ * Defines a configuration-based entity type used for testing.
+ *
+ * @ConfigEntityType(
+ *   id = "test_config_type",
+ *   label = @Translation("Test entity type"),
+ *   handlers = {
+ *     "list_builder" = "Drupal\Core\Entity\EntityListBuilder"
+ *   },
+ *   admin_permission = "administer modules",
+ *   config_prefix = "type",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "label" = "name"
+ *   }
+ * )
+ */
+class TestConfigType extends ConfigEntityBase {
+}