diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeReviewPageTestBase.php b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeReviewPageTestBase.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
@@ -8,9 +8,9 @@
 use Drupal\Tests\migrate_drupal\Traits\CreateTestContentEntitiesTrait;
 
 /**
- * Provides a base class for testing the UpgradeReview page.
+ * Provides a base class for testing migration upgrades in the UI.
  */
-abstract class MigrateUpgradeReviewPageTestBase extends BrowserTestBase {
+abstract class MigrateUpgradeTestBase extends BrowserTestBase {
 
   use MigrationConfigurationTrait;
   use CreateTestContentEntitiesTrait;
@@ -30,25 +30,6 @@
   protected $sourceDatabase;
 
   /**
-   * Modules to enable.
-   *
-   * @var array
-   */
-  public static $modules = [
-    'language',
-    'content_translation',
-    'migrate_drupal_ui',
-    'telephone',
-    'aggregator',
-    'book',
-    'forum',
-    'statistics',
-    'syslog',
-    'tracker',
-    'update',
-  ];
-
-  /**
    * {@inheritdoc}
    */
   protected function setUp() {
@@ -115,96 +96,6 @@
   }
 
   /**
-   * Tests the migrate upgrade review page.
-   *
-   * The form displays two types of information, one is error messages for
-   * migrations that do not have a source_module defined, the other is a list
-   * of modules and their upgrade status. In this test there should be no error
-   * messages because the relevant test modules are not installed. The list
-   * of modules, available and missing, will be complete for all modules
-   * moved to Drupal 8 core. This is accomplished by modifying the source
-   * database to enable all modules that do not include 'test' or 'example' in
-   * their name. This then tests that the noUpgradePath contain a complete list
-   * of modules moved from previous versions of Drupal to Drupal 8.
-   *
-   * Note that this assumption here is that the Drupal 6 and Drupal 7 test
-   * fixtures include all modules that have moved to Drupal 8 core.
-   *
-   */
-  public function testMigrateUpgradeReviewPage() {
-    $connection_options = $this->sourceDatabase->getConnectionOptions();
-    $driver = $connection_options['driver'];
-    $connection_options['prefix'] = $connection_options['prefix']['default'];
-
-    // Use the driver connection form to get the correct options out of the
-    // database settings. This supports all of the databases we test against.
-    $drivers = drupal_get_database_types();
-    $form = $drivers[$driver]->getFormOptions($connection_options);
-    $connection_options = array_intersect_key($connection_options, $form + $form['advanced_options']);
-    $version = $this->getLegacyDrupalVersion($this->sourceDatabase);
-    $edit = [
-      $driver => $connection_options,
-      'source_private_file_path' => $this->getSourceBasePath(),
-      'version' => $version,
-    ];
-    if ($version == 6) {
-      $edit['d6_source_base_path'] = $this->getSourceBasePath();
-    }
-    else {
-      $edit['source_base_path'] = $this->getSourceBasePath();
-    }
-    if (count($drivers) !== 1) {
-      $edit['driver'] = $driver;
-    }
-    $edits = $this->translatePostValues($edit);
-
-    // Enable all modules in the source
-    $this->sourceDatabase->update('system')
-      ->fields(['status'  => 1])
-      ->condition('type', 'module')
-      ->condition('name', '%test%', 'NOT LIKE')
-      ->condition('name', '%example%', 'NOT LIKE')
-      ->execute();
-    $this->sourceDatabase->update('system')
-      ->fields(['status'  => 1])
-      ->condition('type', 'module')
-      ->condition('name', 'simpletest')
-      ->execute();
-
-    // Start the upgrade process.
-    $this->drupalGet('/upgrade');
-    $this->drupalPostForm(NULL, [], t('Continue'));
-    $this->drupalPostForm(NULL, $edits, t('Review upgrade'));
-    $this->drupalPostForm(NULL, [], t('I acknowledge I may lose data. Continue anyway.'));
-
-    // Ensure there are no errors about the missing modules from the test module.
-    $session = $this->assertSession();
-    $session->pageTextNotContains(t('Source module not found for migration_provider_no_annotation.'));
-    $session->pageTextNotContains(t('Source module not found for migration_provider_test.'));
-    $session->pageTextNotContains(t('Destination module not found for migration_provider_test'));
-    // Ensure there are no errors about any other missing migration providers.
-    $session->pageTextNotContains(t('module not found'));
-
-    // Test the available migration paths.
-    $available_paths = $this->getAvailablePaths();
-    foreach ($available_paths as $available) {
-      $session->elementExists('xpath', "//span[contains(@class, 'checked') and text() = '$available']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'warning') and text() = '$available']");
-    }
-
-    // Test the missing migration paths.
-    $missing_paths = $this->getMissingPaths();
-    foreach ($missing_paths as $missing) {
-      $session->elementExists('xpath', "//span[contains(@class, 'warning') and text() = '$missing']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'checked') and text() = '$missing']");
-    }
-
-    // Test the total count of missing and available paths.
-    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--warning')]", count($missing_paths));
-    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--checked')]", count($available_paths));
-  }
-
-  /**
    * Transforms a nested array into a flat array suitable for BrowserTestBase::drupalPostForm().
    *
    * @param array $values
@@ -227,6 +118,33 @@
   }
 
   /**
+   * Tests the displayed upgrade paths.
+   *
+   * @param $session
+   * @param $available_paths
+   *   An array of modules that will be upgraded.
+   * @param $missing_paths
+   *   An array of modules that will not be upgraded.
+   */
+  protected function assertUpgradePaths($session, $available_paths, $missing_paths) {
+    // Test the available migration paths.
+    foreach ($available_paths as $available) {
+      $session->elementExists('xpath', "//span[contains(@class, 'checked') and text() = '$available']");
+      $session->elementNotExists('xpath', "//span[contains(@class, 'warning') and text() = '$available']");
+    }
+
+    // Test the missing migration paths.
+    foreach ($missing_paths as $missing) {
+      $session->elementExists('xpath', "//span[contains(@class, 'warning') and text() = '$missing']");
+      $session->elementNotExists('xpath', "//span[contains(@class, 'checked') and text() = '$missing']");
+    }
+
+    // Test the total count of missing and available paths.
+    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--warning')]", count($missing_paths));
+    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--checked')]", count($available_paths));
+  }
+
+  /**
    * Gets the source base path for the concrete test.
    *
    * @return string
@@ -235,6 +153,14 @@
   abstract protected function getSourceBasePath();
 
   /**
+   * Gets the expected number of entities per entity type after migration.
+   *
+   * @return int[]
+   *   An array of expected counts keyed by entity type ID.
+   */
+  abstract protected function getEntityCounts();
+
+  /**
    * Gets the available upgrade paths.
    *
    * @return string[]
diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
@@ -3,7 +3,6 @@
 namespace Drupal\Tests\migrate_drupal_ui\Functional;
 
 use Drupal\Core\Database\Database;
-use Drupal\migrate\Plugin\MigrateIdMapInterface;
 use Drupal\migrate_drupal\MigrationConfigurationTrait;
 use Drupal\Tests\BrowserTestBase;
 use Drupal\Tests\migrate_drupal\Traits\CreateTestContentEntitiesTrait;
@@ -31,24 +30,6 @@
   protected $sourceDatabase;
 
   /**
-   * Modules to enable.
-   *
-   * @var array
-   */
-  public static $modules = [
-    'language',
-    'content_translation',
-    'migrate_drupal_ui',
-    'telephone',
-    'aggregator',
-    'book',
-    'forum',
-    'statistics',
-    'migration_provider_test',
-    'upgrade_form_alter_test',
-  ];
-
-  /**
    * {@inheritdoc}
    */
   protected function setUp() {
@@ -58,9 +39,6 @@
 
     // Log in as user 1. Migrations in the UI can only be performed as user 1.
     $this->drupalLogin($this->rootUser);
-
-    // Create content.
-    $this->createContent();
   }
 
   /**
@@ -118,155 +96,6 @@
   }
 
   /**
-   * Executes all steps of migrations upgrade.
-   */
-  public function testMigrateUpgrade() {
-    $connection_options = $this->sourceDatabase->getConnectionOptions();
-    $this->drupalGet('/upgrade');
-    $session = $this->assertSession();
-    $session->responseContains('Upgrade a site by importing its files and the data from its database into a clean and empty new install of Drupal 8.');
-
-    $this->drupalPostForm(NULL, [], t('Continue'));
-    $this->assertText('Provide credentials for the database of the Drupal site you want to upgrade.');
-    $this->assertFieldByName('mysql[host]');
-
-    $driver = $connection_options['driver'];
-    $connection_options['prefix'] = $connection_options['prefix']['default'];
-
-    // Use the driver connection form to get the correct options out of the
-    // database settings. This supports all of the databases we test against.
-    $drivers = drupal_get_database_types();
-    $form = $drivers[$driver]->getFormOptions($connection_options);
-    $connection_options = array_intersect_key($connection_options, $form + $form['advanced_options']);
-    $version = $this->getLegacyDrupalVersion($this->sourceDatabase);
-    $edit = [
-      $driver => $connection_options,
-      'source_private_file_path' => $this->getSourceBasePath(),
-      'version' => $version,
-    ];
-    if ($version == 6) {
-      $edit['d6_source_base_path'] = $this->getSourceBasePath();
-    }
-    else {
-      $edit['source_base_path'] = $this->getSourceBasePath();
-    }
-    if (count($drivers) !== 1) {
-      $edit['driver'] = $driver;
-    }
-    $edits = $this->translatePostValues($edit);
-
-    // Ensure submitting the form with invalid database credentials gives us a
-    // nice warning.
-    $this->drupalPostForm(NULL, [$driver . '[database]' => 'wrong'] + $edits, t('Review upgrade'));
-    $this->assertText('Resolve the issue below to continue the upgrade.');
-
-    $this->drupalPostForm(NULL, $edits, t('Review upgrade'));
-    $session->pageTextContains('WARNING: Content may be overwritten on your new site.');
-    $session->pageTextContains('There is conflicting content of these types:');
-    $session->pageTextContains('aggregator feed entities');
-    $session->pageTextContains('aggregator feed item entities');
-    $session->pageTextContains('custom block entities');
-    $session->pageTextContains('custom menu link entities');
-    $session->pageTextContains('file entities');
-    $session->pageTextContains('taxonomy term entities');
-    $session->pageTextContains('user entities');
-    $session->pageTextContains('comments');
-    $session->pageTextContains('content item revisions');
-    $session->pageTextContains('content items');
-    $session->pageTextContains('There is translated content of these types:');
-    $this->drupalPostForm(NULL, [], t('I acknowledge I may lose data. Continue anyway.'));
-    $this->assertResponse(200);
-    $this->assertText('Upgrade analysis report');
-    // Ensure we get errors about missing modules.
-    $session->pageTextContains(t('Source module not found for migration_provider_no_annotation.'));
-    $session->pageTextContains(t('Source module not found for migration_provider_test.'));
-    $session->pageTextContains(t('Destination module not found for migration_provider_test'));
-
-    // Uninstall the module causing the missing module error messages.
-    $this->container->get('module_installer')->uninstall(['migration_provider_test'], TRUE);
-
-    // Restart the upgrade process.
-    $this->drupalGet('/upgrade');
-    $session->responseContains('Upgrade a site by importing its files and the data from its database into a clean and empty new install of Drupal 8.');
-
-    $this->drupalPostForm(NULL, [], t('Continue'));
-    $session->pageTextContains('Provide credentials for the database of the Drupal site you want to upgrade.');
-    $session->fieldExists('mysql[host]');
-
-    $this->drupalPostForm(NULL, $edits, t('Review upgrade'));
-    $session->pageTextContains('WARNING: Content may be overwritten on your new site.');
-    $this->drupalPostForm(NULL, [], t('I acknowledge I may lose data. Continue anyway.'));
-    $session->statusCodeEquals(200);
-    $session->pageTextContains('Upgrade analysis report');
-    // Ensure there are no errors about the missing modules from the test module.
-    $session->pageTextNotContains(t('Source module not found for migration_provider_no_annotation.'));
-    $session->pageTextNotContains(t('Source module not found for migration_provider_test.'));
-    $session->pageTextNotContains(t('Destination module not found for migration_provider_test'));
-    // Ensure there are no errors about any other missing migration providers.
-    $session->pageTextNotContains(t('module not found'));
-
-    // Test the available migration paths.
-    $all_available = $this->getAvailablePaths();
-    foreach ($all_available as $available) {
-      $session->elementExists('xpath', "//span[contains(@class, 'checked') and text() = '$available']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'warning') and text() = '$available']");
-    }
-
-    // Test the missing migration paths.
-    $all_missing = $this->getMissingPaths();
-    foreach ($all_missing as $missing) {
-      $session->elementExists('xpath', "//span[contains(@class, 'warning') and text() = '$missing']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'checked') and text() = '$missing']");
-    }
-
-    // Test the total count of missing and available paths.
-    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--warning')]", count($all_missing));
-    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--checked')]", count($all_available));
-
-    $this->drupalPostForm(NULL, [], t('Perform upgrade'));
-    $this->assertText(t('Congratulations, you upgraded Drupal!'));
-
-    // Have to reset all the statics after migration to ensure entities are
-    // loadable.
-    $this->resetAll();
-
-    $expected_counts = $this->getEntityCounts();
-    foreach (array_keys(\Drupal::entityTypeManager()
-      ->getDefinitions()) as $entity_type) {
-      $real_count = \Drupal::entityQuery($entity_type)->count()->execute();
-      $expected_count = isset($expected_counts[$entity_type]) ? $expected_counts[$entity_type] : 0;
-      $this->assertEqual($expected_count, $real_count, "Found $real_count $entity_type entities, expected $expected_count.");
-    }
-
-    $plugin_manager = \Drupal::service('plugin.manager.migration');
-    /** @var \Drupal\migrate\Plugin\Migration[] $all_migrations */
-    $all_migrations = $plugin_manager->createInstancesByTag('Drupal ' . $version);
-    foreach ($all_migrations as $migration) {
-      $id_map = $migration->getIdMap();
-      foreach ($id_map as $source_id => $map) {
-        // Convert $source_id into a keyless array so that
-        // \Drupal\migrate\Plugin\migrate\id_map\Sql::getSourceHash() works as
-        // expected.
-        $source_id_values = array_values(unserialize($source_id));
-        $row = $id_map->getRowBySource($source_id_values);
-        $destination = serialize($id_map->currentDestination());
-        $message = "Migration of $source_id to $destination as part of the {$migration->id()} migration. The source row status is " . $row['source_row_status'];
-        // A completed migration should have maps with
-        // MigrateIdMapInterface::STATUS_IGNORED or
-        // MigrateIdMapInterface::STATUS_IMPORTED.
-        if ($row['source_row_status'] == MigrateIdMapInterface::STATUS_FAILED || $row['source_row_status'] == MigrateIdMapInterface::STATUS_NEEDS_UPDATE) {
-          $this->fail($message);
-        }
-        else {
-          $this->pass($message);
-        }
-      }
-    }
-    \Drupal::service('module_installer')->install(['forum']);
-    \Drupal::service('module_installer')->install(['book']);
-  }
-
-  /**
    * Transforms a nested array into a flat array suitable for BrowserTestBase::drupalPostForm().
    *
    * @param array $values
@@ -289,6 +118,33 @@
   }
 
   /**
+   * Tests the displayed upgrade paths.
+   *
+   * @param $session
+   * @param $available_paths
+   *   An array of modules that will be upgraded.
+   * @param $missing_paths
+   *   An array of modules that will not be upgraded.
+   */
+  protected function assertUpgradePaths($session, $available_paths, $missing_paths) {
+    // Test the available migration paths.
+    foreach ($available_paths as $available) {
+      $session->elementExists('xpath', "//span[contains(@class, 'checked') and text() = '$available']");
+      $session->elementNotExists('xpath', "//span[contains(@class, 'warning') and text() = '$available']");
+    }
+
+    // Test the missing migration paths.
+    foreach ($missing_paths as $missing) {
+      $session->elementExists('xpath', "//span[contains(@class, 'warning') and text() = '$missing']");
+      $session->elementNotExists('xpath', "//span[contains(@class, 'checked') and text() = '$missing']");
+    }
+
+    // Test the total count of missing and available paths.
+    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--warning')]", count($missing_paths));
+    $session->elementsCount('xpath', "//span[contains(@class, 'upgrade-analysis-report__status-icon--checked')]", count($available_paths));
+  }
+
+  /**
    * Gets the source base path for the concrete test.
    *
    * @return string
diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6ReviewPageTest.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6ReviewPageTest.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6ReviewPageTest.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6ReviewPageTest.php
@@ -3,7 +3,6 @@
 namespace Drupal\Tests\migrate_drupal_ui\Functional\d6;
 
 use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeReviewPageTestBase;
-use Drupal\user\Entity\User;
 
 /**
  * Tests migrate upgrade review page for Drupal 6.
@@ -21,13 +20,6 @@
   }
 
   /**
-   * {@inheritdoc}
-   */
-  protected function getSourceBasePath() {
-    return __DIR__ . '/files';
-  }
-
-  /**
    * {@inheritdoc}
    */
   protected function getAvailablePaths() {
diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Tests\migrate_drupal_ui\Functional\d6;
 
-use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeTestBase;
+use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeTest;
 use Drupal\user\Entity\User;
 
 /**
@@ -12,7 +12,7 @@
  *
  * @group migrate_drupal_ui
  */
-class MigrateUpgrade6Test extends MigrateUpgradeTestBase {
+class MigrateUpgrade6Test extends MigrateUpgradeTest {
 
   /**
    * {@inheritdoc}
@@ -25,13 +25,6 @@
   /**
    * {@inheritdoc}
    */
-  protected function getSourceBasePath() {
-    return __DIR__ . '/files';
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   protected function getEntityCounts() {
     return [
       'aggregator_item' => 1,
diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7ReviewPageTest.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7ReviewPageTest.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7ReviewPageTest.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7ReviewPageTest.php
@@ -3,7 +3,6 @@
 namespace Drupal\Tests\migrate_drupal_ui\Functional\d7;
 
 use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeReviewPageTestBase;
-use Drupal\user\Entity\User;
 
 /**
  * Tests migrate upgrade review page for Drupal 7.
@@ -21,13 +20,6 @@
   }
 
   /**
-   * {@inheritdoc}
-   */
-  protected function getSourceBasePath() {
-    return __DIR__ . '/files';
-  }
-
-  /**
    * {@inheritdoc}
    */
   protected function getAvailablePaths() {
diff -u b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
--- b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Tests\migrate_drupal_ui\Functional\d7;
 
-use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeTestBase;
+use Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeTest;
 use Drupal\user\Entity\User;
 
 /**
@@ -12,7 +12,7 @@
  *
  * @group migrate_drupal_ui
  */
-class MigrateUpgrade7Test extends MigrateUpgradeTestBase {
+class MigrateUpgrade7Test extends MigrateUpgradeTest {
 
   /**
    * {@inheritdoc}
only in patch2:
unchanged:
--- /dev/null
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeReviewPageTestBase.php
@@ -0,0 +1,126 @@
+<?php
+
+namespace Drupal\Tests\migrate_drupal_ui\Functional;
+
+use Drupal\migrate_drupal\MigrationConfigurationTrait;
+use Drupal\Tests\migrate_drupal\Traits\CreateTestContentEntitiesTrait;
+
+/**
+ * Provides a base class for testing the UpgradeReview page.
+ */
+abstract class MigrateUpgradeReviewPageTestBase extends MigrateUpgradeTestBase {
+
+  use MigrationConfigurationTrait;
+  use CreateTestContentEntitiesTrait;
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = [
+    'language',
+    'content_translation',
+    'migrate_drupal_ui',
+    'telephone',
+    'aggregator',
+    'book',
+    'forum',
+    'statistics',
+    'syslog',
+    'tracker',
+    'update',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getSourceBasePath() {
+    return __DIR__ . '/files';
+  }
+
+  /**
+   * Tests the migrate upgrade review page.
+   *
+   * The form displays two types of information, one is error messages for
+   * migrations that do not have a source_module defined, the other is a list
+   * of modules and their upgrade status. In this test there should be no error
+   * messages because the relevant test modules are not installed. The list
+   * of modules, available and missing, will be complete for all modules
+   * moved to Drupal 8 core. This is accomplished by modifying the source
+   * database to enable all modules that do not include 'test' or 'example' in
+   * their name. This then tests that the noUpgradePath contain a complete list
+   * of modules moved from previous versions of Drupal to Drupal 8.
+   *
+   * Note that this assumption here is that the Drupal 6 and Drupal 7 test
+   * fixtures include all modules that have moved to Drupal 8 core.
+   *
+   */
+  public function testMigrateUpgradeReviewPage() {
+    $connection_options = $this->sourceDatabase->getConnectionOptions();
+    $driver = $connection_options['driver'];
+    $connection_options['prefix'] = $connection_options['prefix']['default'];
+
+    // Use the driver connection form to get the correct options out of the
+    // database settings. This supports all of the databases we test against.
+    $drivers = drupal_get_database_types();
+    $form = $drivers[$driver]->getFormOptions($connection_options);
+    $connection_options = array_intersect_key($connection_options, $form + $form['advanced_options']);
+    $version = $this->getLegacyDrupalVersion($this->sourceDatabase);
+    $edit = [
+      $driver => $connection_options,
+      'source_private_file_path' => $this->getSourceBasePath(),
+      'version' => $version,
+    ];
+    if ($version == 6) {
+      $edit['d6_source_base_path'] = $this->getSourceBasePath();
+    }
+    else {
+      $edit['source_base_path'] = $this->getSourceBasePath();
+    }
+    if (count($drivers) !== 1) {
+      $edit['driver'] = $driver;
+    }
+    $edits = $this->translatePostValues($edit);
+
+    // Enable all modules in the source
+    $this->sourceDatabase->update('system')
+      ->fields(['status'  => 1])
+      ->condition('type', 'module')
+      ->condition('name', '%test%', 'NOT LIKE')
+      ->condition('name', '%example%', 'NOT LIKE')
+      ->execute();
+    $this->sourceDatabase->update('system')
+      ->fields(['status'  => 1])
+      ->condition('type', 'module')
+      ->condition('name', 'simpletest')
+      ->execute();
+
+    // Start the upgrade process.
+    $this->drupalGet('/upgrade');
+    $this->drupalPostForm(NULL, [], t('Continue'));
+    $this->drupalPostForm(NULL, $edits, t('Review upgrade'));
+    $this->drupalPostForm(NULL, [], t('I acknowledge I may lose data. Continue anyway.'));
+
+    // Ensure there are no errors about the missing modules from the test module.
+    $session = $this->assertSession();
+    $session->pageTextNotContains(t('Source module not found for migration_provider_no_annotation.'));
+    $session->pageTextNotContains(t('Source module not found for migration_provider_test.'));
+    $session->pageTextNotContains(t('Destination module not found for migration_provider_test'));
+    // Ensure there are no errors about any other missing migration providers.
+    $session->pageTextNotContains(t('module not found'));
+
+    // Test the upgrade paths.
+    $available_paths = $this->getAvailablePaths();
+    $missing_paths = $this->getMissingPaths();
+    $this->assertUpgradePaths($session, $available_paths, $missing_paths);
+ }
+
+   /**
+   * {@inheritdoc}
+   */
+  protected function getEntityCounts() {
+    return [];
+  }
+
+}
only in patch2:
unchanged:
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTest.php
@@ -2,35 +2,19 @@
 
 namespace Drupal\Tests\migrate_drupal_ui\Functional;
 
-use Drupal\Core\Database\Database;
 use Drupal\migrate\Plugin\MigrateIdMapInterface;
 use Drupal\migrate_drupal\MigrationConfigurationTrait;
-use Drupal\Tests\BrowserTestBase;
 use Drupal\Tests\migrate_drupal\Traits\CreateTestContentEntitiesTrait;
 
 /**
  * Provides a base class for testing migration upgrades in the UI.
  */
-abstract class MigrateUpgradeTestBase extends BrowserTestBase {
+abstract class MigrateUpgradeTest extends MigrateUpgradeTestBase {
 
   use MigrationConfigurationTrait;
   use CreateTestContentEntitiesTrait;
 
   /**
-   * Use the Standard profile to test help implementations of many core modules.
-   *
-   * @var string
-   */
-  protected $profile = 'standard';
-
-  /**
-   * The source database connection.
-   *
-   * @var \Drupal\Core\Database\Connection
-   */
-  protected $sourceDatabase;
-
-  /**
    * Modules to enable.
    *
    * @var array
@@ -45,6 +29,7 @@
     'forum',
     'statistics',
     'migration_provider_test',
+    'upgrade_form_alter_test',
   ];
 
   /**
@@ -52,68 +37,16 @@
    */
   protected function setUp() {
     parent::setUp();
-    $this->createMigrationConnection();
-    $this->sourceDatabase = Database::getConnection('default', 'migrate_drupal_ui');
-
-    // Log in as user 1. Migrations in the UI can only be performed as user 1.
-    $this->drupalLogin($this->rootUser);
 
     // Create content.
     $this->createContent();
   }
 
   /**
-   * Loads a database fixture into the source database connection.
-   *
-   * @param string $path
-   *   Path to the dump file.
-   */
-  protected function loadFixture($path) {
-    $default_db = Database::getConnection()->getKey();
-    Database::setActiveConnection($this->sourceDatabase->getKey());
-
-    if (substr($path, -3) == '.gz') {
-      $path = 'compress.zlib://' . $path;
-    }
-    require $path;
-
-    Database::setActiveConnection($default_db);
-  }
-
-  /**
-   * Changes the database connection to the prefixed one.
-   *
-   * @todo Remove when we don't use global. https://www.drupal.org/node/2552791
-   */
-  protected function createMigrationConnection() {
-    $connection_info = Database::getConnectionInfo('default')['default'];
-    if ($connection_info['driver'] === 'sqlite') {
-      // Create database file in the test site's public file directory so that
-      // \Drupal\simpletest\TestBase::restoreEnvironment() will delete this once
-      // the test is complete.
-      $file = $this->publicFilesDirectory . '/' . $this->testId . '-migrate.db.sqlite';
-      touch($file);
-      $connection_info['database'] = $file;
-      $connection_info['prefix'] = '';
-    }
-    else {
-      $prefix = is_array($connection_info['prefix']) ? $connection_info['prefix']['default'] : $connection_info['prefix'];
-      // Simpletest uses fixed length prefixes. Create a new prefix for the
-      // source database. Adding to the end of the prefix ensures that
-      // \Drupal\simpletest\TestBase::restoreEnvironment() will remove the
-      // additional tables.
-      $connection_info['prefix'] = $prefix . '0';
-    }
-
-    Database::addConnectionInfo('migrate_drupal_ui', 'default', $connection_info);
-  }
-
-  /**
    * {@inheritdoc}
    */
-  protected function tearDown() {
-    Database::removeConnection('migrate_drupal_ui');
-    parent::tearDown();
+  protected function getSourceBasePath() {
+    return __DIR__ . '/files';
   }
 
   /**
@@ -204,19 +137,10 @@ public function testMigrateUpgrade() {
     // Ensure there are no errors about any other missing migration providers.
     $session->pageTextNotContains(t('module not found'));
 
-    // Test the available migration paths.
-    $all_available = $this->getAvailablePaths();
-    foreach ($all_available as $available) {
-      $session->elementExists('xpath', "//span[contains(@class, 'checked') and text() = '$available']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'warning') and text() = '$available']");
-    }
-
-    // Test the missing migration paths.
-    $all_missing = $this->getMissingPaths();
-    foreach ($all_missing as $missing) {
-      $session->elementExists('xpath', "//span[contains(@class, 'warning') and text() = '$missing']");
-      $session->elementNotExists('xpath', "//span[contains(@class, 'checked') and text() = '$missing']");
-    }
+    // Test the upgrade paths.
+    $available_paths = $this->getAvailablePaths();
+    $missing_paths = $this->getMissingPaths();
+    $this->assertUpgradePaths($session, $available_paths, $missing_paths);
 
     $this->drupalPostForm(NULL, [], t('Perform upgrade'));
     $this->assertText(t('Congratulations, you upgraded Drupal!'));
@@ -261,58 +185,4 @@ public function testMigrateUpgrade() {
     \Drupal::service('module_installer')->install(['book']);
   }
 
-  /**
-   * Transforms a nested array into a flat array suitable for BrowserTestBase::drupalPostForm().
-   *
-   * @param array $values
-   *   A multi-dimensional form values array to convert.
-   *
-   * @return array
-   *   The flattened $edit array suitable for BrowserTestBase::drupalPostForm().
-   */
-  protected function translatePostValues(array $values) {
-    $edit = [];
-    // The easiest and most straightforward way to translate values suitable for
-    // BrowserTestBase::drupalPostForm() is to actually build the POST data string
-    // and convert the resulting key/value pairs back into a flat array.
-    $query = http_build_query($values);
-    foreach (explode('&', $query) as $item) {
-      list($key, $value) = explode('=', $item);
-      $edit[urldecode($key)] = urldecode($value);
-    }
-    return $edit;
-  }
-
-  /**
-   * Gets the source base path for the concrete test.
-   *
-   * @return string
-   *   The source base path.
-   */
-  abstract protected function getSourceBasePath();
-
-  /**
-   * Gets the expected number of entities per entity type after migration.
-   *
-   * @return int[]
-   *   An array of expected counts keyed by entity type ID.
-   */
-  abstract protected function getEntityCounts();
-
-  /**
-   * Gets the available upgrade paths.
-   *
-   * @return string[]
-   *   An array of available upgrade paths.
-   */
-  abstract protected function getAvailablePaths();
-
-  /**
-   * Gets the missing upgrade paths.
-   *
-   * @return string[]
-   *   An array of missing upgrade paths.
-   */
-  abstract protected function getMissingPaths();
-
 }