Issue #2143405 by chx, bdone: Split migrate into to migrate and migrate_drupal.

core/modules/migrate_drupal/config/migrate.migration.d6_system_performance.yml

+id: d6_system_performance
+source:
+    plugin: drupal6_variable
+    variables:
+        - preprocess_css
+        - preprocess_js
+        - cache_lifetime
+process:
+    'css:preprocess': preprocess_css
+    'js:preprocess': preprocess_js
+    'cache:page:max_age': cache_lifetime
+destination:
+    plugin: d8_config
+    config_name: system.performance

core/modules/migrate/lib/Drupal/migrate/Plugin/migrate/source/D6Variable.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Plugin/migrate/source/D6Variable.php

@@ -5,10 +5,10 @@
  * Contains \Drupal\migrate\Plugin\migrate\source\d6\Variable.
  */
 
-namespace Drupal\migrate\Plugin\migrate\source;
+namespace Drupal\migrate_drupal\Plugin\migrate\source;
 
 use Drupal\migrate\Entity\MigrationInterface;
-use Drupal\migrate\Plugin\migrate\source\d6\Drupal6SqlBase;
+use Drupal\migrate_drupal\Plugin\migrate\source\d6\Drupal6SqlBase;
 
 /**
  * Drupal 6 variable source from database.

core/modules/migrate/lib/Drupal/migrate/Plugin/migrate/source/d6/Drupal6SqlBase.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Plugin/migrate/source/d6/Drupal6SqlBase.php

@@ -5,7 +5,7 @@
  * Contains \Drupal\migrate\Plugin\migrate\source\d6\Drupal6SqlBase.
  */
 
-namespace Drupal\migrate\Plugin\migrate\source\d6;
+namespace Drupal\migrate_drupal\Plugin\migrate\source\d6;
 
 use Drupal\migrate\Plugin\migrate\source\SqlBase;
 

core/modules/migrate/lib/Drupal/migrate/Tests/Dump/Drupal6SystemCron.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemCron.php

@@ -5,7 +5,7 @@
  * Contains \Drupal\migrate\Tests\Drupal6SystemCron.
  */
 
-namespace Drupal\migrate\Tests\Dump;
+namespace Drupal\migrate_drupal\Tests\Dump;
 
 use Drupal\Core\Database\Connection;
 

core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemPerformance.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\migrate\Tests\Drupal6SystemPerformance.
+ */
+
+namespace Drupal\migrate_drupal\Tests\Dump;
+
+use Drupal\Core\Database\Connection;
+
+/**
+ * Database dump for testing system.performance.yml migration.
+ */
+class Drupal6SystemPerformance {
+
+  /**
+   * Sample database schema and values.
+   *
+   * @param \Drupal\Core\Database\Connection $database
+   *   The database connection.
+   */
+  public static function load(Connection $database) {
+    $database->schema()->createTable('variable', array(
+      'fields' => array(
+        'name' => array(
+          'type' => 'varchar',
+          'length' => 128,
+          'not null' => TRUE,
+          'default' => '',
+        ),
+        'value' => array(
+          'type' => 'blob',
+          'not null' => TRUE,
+          'size' => 'big',
+          'translatable' => TRUE,
+        ),
+      ),
+      'primary key' => array(
+        'name',
+      ),
+      'module' => 'system',
+      'name' => 'variable',
+    ));
+    $database->insert('variable')->fields(array(
+      'name',
+      'value',
+    ))
+    ->values(array(
+      'name' => 'preprocess_css',
+      'value' => 'i:0;',
+    ))
+    ->values(array(
+      'name' => 'preprocess_js',
+      'value' => 'i:0;',
+    ))
+    ->values(array(
+      'name' => 'cache_lifetime',
+      'value' => 'i:0;',
+    ))
+    ->execute();
+  }
+
+}

core/modules/migrate/lib/Drupal/migrate/Tests/Dump/Drupal6SystemRss.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemRss.php

@@ -5,7 +5,7 @@
  * Contains \Drupal\migrate\Tests\Drupal6SystemRss.
  */
 
-namespace Drupal\migrate\Tests\Dump;
+namespace Drupal\migrate_drupal\Tests\Dump;
 
 use Drupal\Core\Database\Connection;
 

core/modules/migrate/lib/Drupal/migrate/Tests/Dump/Drupal6SystemSite.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemSite.php

 <?php
 
-namespace Drupal\migrate\Tests\Dump;
+namespace Drupal\migrate_drupal\Tests\Dump;
 
 use Drupal\Core\Database\Connection;
 

core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/MigrateDrupalTestBase.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\migrate_drupal\Tests\MigrateDrupalTestBase.
+ */
+
+namespace Drupal\migrate_drupal\Tests;
+
+use Drupal\migrate\Tests\MigrateTestBase;
+
+class MigrateDrupalTestBase extends MigrateTestBase {
+
+  public static $modules = array('migrate_drupal');
+}

core/modules/migrate/lib/Drupal/migrate/Tests/MigrateSystemConfigsTest.php → core/modules/migrate_drupal/lib/Drupal/migrate_drupal/Tests/MigrateSystemConfigsTest.php

@@ -5,12 +5,12 @@
  * Contains \Drupal\system\Tests\Upgrade\MigrateSystemSiteTest.
  */
 
-namespace Drupal\migrate\Tests;
+namespace Drupal\migrate_drupal\Tests;
 
 use Drupal\migrate\MigrateMessage;
 use Drupal\migrate\MigrateExecutable;
 
-class MigrateSystemConfigsTest extends MigrateTestBase {
+class MigrateSystemConfigsTest extends MigrateDrupalTestBase {
 
   /**
    * {@inheritdoc}
@@ -19,14 +19,14 @@ public static function getInfo() {
     return array(
       'name'  => 'Migrate variables to system.*.yml',
       'description'  => 'Upgrade variables to system.*.yml',
-      'group' => 'Migrate',
+      'group' => 'Migrate Drupal',
     );
   }
 
   function testSystemSite() {
     $migration = entity_load('migration', 'd6_system_site');
     $dumps = array(
-      drupal_get_path('module', 'migrate') . '/lib/Drupal/migrate/Tests/Dump/Drupal6SystemSite.php',
+      drupal_get_path('module', 'migrate_drupal') . '/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemSite.php',
     );
     $this->prepare($migration, $dumps);
     $executable = new MigrateExecutable($migration, new MigrateMessage);
@@ -48,7 +48,7 @@ function testSystemSite() {
   public function testSystemCron() {
     $migration = entity_load('migration', 'd6_system_cron');
     $dumps = array(
-      drupal_get_path('module', 'migrate') . '/lib/Drupal/migrate/Tests/Dump/Drupal6SystemCron.php',
+      drupal_get_path('module', 'migrate_drupal') . '/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemCron.php',
     );
     $this->prepare($migration, $dumps);
     $executable = new MigrateExecutable($migration, new MigrateMessage());
@@ -64,7 +64,7 @@ public function testSystemCron() {
   public function testSystemRss() {
     $migration = entity_load('migration', 'd6_system_rss');
     $dumps = array(
-      drupal_get_path('module', 'migrate') . '/lib/Drupal/migrate/Tests/Dump/Drupal6SystemRss.php',
+      drupal_get_path('module', 'migrate_drupal') . '/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemRss.php',
     );
     $this->prepare($migration, $dumps);
     $executable = new MigrateExecutable($migration, new MigrateMessage());
@@ -72,4 +72,21 @@ public function testSystemRss() {
     $config = \Drupal::config('system.rss');
     $this->assertIdentical($config->get('items.limit'), 10);
   }
+
+  /**
+   * Tests migration of system (Performance) variables to system.performance.yml.
+   */
+  public function testSystemPerformance() {
+    $migration = entity_load('migration', 'd6_system_performance');
+    $dumps = array(
+      drupal_get_path('module', 'migrate_drupal') . '/lib/Drupal/migrate_drupal/Tests/Dump/Drupal6SystemPerformance.php',
+    );
+    $this->prepare($migration, $dumps);
+    $executable = new MigrateExecutable($migration, new MigrateMessage());
+    $executable->import();
+    $config = \Drupal::config('system.performance');
+    $this->assertIdentical($config->get('css.preprocess'), 0);
+    $this->assertIdentical($config->get('js.preprocess'), 0);
+    $this->assertIdentical($config->get('cache.page.max_age'), 0);
+  }
 }

core/modules/migrate_drupal/migrate_drupal.info.yml

+name: Migrate Drupal
+type: module
+description: 'Contains migrations from olders Drupal versions.'
+package: Core
+version: VERSION
+core: 8.x

core/modules/migrate/tests/Drupal/migrate/Tests/D6VariableTest.php → core/modules/migrate_drupal/tests/Drupal/migrate_drupal/Tests/D6VariableTest.php

@@ -5,15 +5,17 @@
  * Contains \Drupal\migrate\Tests\D6VariableSourceTest.
  */
 
-namespace Drupal\migrate\Tests;
+namespace Drupal\migrate_drupal\Tests;
+
+use Drupal\migrate\Tests\MigrateSqlSourceTestCase;
 
 /**
- * @group migrate
+ * @group migrate_drupal
  * @group Drupal
  */
 class D6VariableTest extends MigrateSqlSourceTestCase {
 
-  const PLUGIN_CLASS = 'Drupal\migrate\Plugin\migrate\source\D6Variable';
+  const PLUGIN_CLASS = 'Drupal\migrate_drupal\Plugin\migrate\source\D6Variable';
 
   protected $migrationConfiguration = array(
     'id' => 'test',
@@ -53,17 +55,17 @@ public static function getInfo() {
     return array(
       'name' => 'D6 variable source functionality',
       'description' => 'Tests D6 variable source plugin.',
-      'group' => 'Migrate',
+      'group' => 'Migrate Drupal',
     );
   }
 
 }
 
-namespace Drupal\migrate\Tests\source;
+namespace Drupal\migrate_drupal\Tests\source;
 
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Extension\ModuleHandlerInterface;
-use Drupal\migrate\Plugin\migrate\source\D6Variable;
+use Drupal\migrate_drupal\Plugin\migrate\source\D6Variable;
 
 class TestD6Variable extends D6Variable {
   function setDatabase(Connection $database) {