reverted:
--- b/core/modules/migrate/tests/modules/migrate_high_water_test/src/Plugin/migrate/source/HighWaterTest.php
+++ a/core/modules/migrate/tests/modules/migrate_high_water_test/src/Plugin/migrate/source/HighWaterTest.php
@@ -8,8 +8,7 @@
  * Source plugin for migration high water tests.
  *
  * @MigrateSource(
+ *   id = "high_water_test"
- *   id = "high_water_test",
- *   source_provider = "migrate_high_water_test"
  * )
  */
 class HighWaterTest extends SqlBase {
diff -u b/core/modules/migrate_drupal_ui/tests/src/Kernel/ProvidersExistTest.php b/core/modules/migrate_drupal_ui/tests/src/Kernel/ProvidersExistTest.php
--- b/core/modules/migrate_drupal_ui/tests/src/Kernel/ProvidersExistTest.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Kernel/ProvidersExistTest.php
@@ -3,6 +3,7 @@
 namespace Drupal\Tests\migrate_drupal_ui\Kernel;
 
 Use Drupal\Component\Render\FormattableMarkup;
+use Drupal\KernelTests\FileSystemModuleDiscoveryDataProviderTrait;
 use Drupal\Tests\migrate_drupal\Kernel\MigrateDrupalTestBase;
 
 /**
@@ -12,10 +13,11 @@
  */
 class ProvidersExistTest extends MigrateDrupalTestBase {
 
+  use FileSystemModuleDiscoveryDataProviderTrait;
   /**
    * {@inheritdoc}
    */
-  public static $modules = ['migrate_drupal', 'migrate_drupal_ui'];
+  public static $modules = ['migrate_drupal_ui', 'provider_test'];
 
   /**
    * Tests that providers exist for all source and destination plugins.
@@ -23,7 +25,7 @@
   public function testProvidersExist() {
     // Install all available modules.
     $module_handler = $this->container->get('module_handler');
-    $modules = system_rebuild_module_data();
+    $modules = $this->coreModuleListDataProvider();
     $modules_enabled = $module_handler->getModuleList();
     $modules_to_enable = array_keys(array_diff_key($modules, $modules_enabled));
     $this->enableModules($modules_to_enable);
reverted:
--- b/core/modules/taxonomy/tests/modules/taxonomy_term_stub_test/migrations/taxonomy_term_stub_test.yml
+++ a/core/modules/taxonomy/tests/modules/taxonomy_term_stub_test/migrations/taxonomy_term_stub_test.yml
@@ -13,7 +13,6 @@
   ids:
     id:
       type: integer
-  provider: taxonomy_term_stub_test
 process:
   tid: id
   vid: vocab