only in patch2:
unchanged:
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/MigrateUpgradeTestBase.php
@@ -178,6 +178,21 @@ public function testMigrateUpgrade() {
     $this->assertSession()->pageTextNotContains(t('Destination module not found for migration_provider_test'));
     // Ensure there are no errors about any other missing migration providers.
     $this->assertSession()->pageTextNotContains(t('module not found'));
+
+    // Test the available migration paths.
+    $all_available = $this->getAvailablePaths();
+    foreach ($all_available as $available) {
+      $this->assertSession()->elementExists('xpath', '//table[@id="edit-available-module-list-module-list"]//td[text()="' . $available . '"]');
+      $this->assertSession()->elementNotExists('xpath', '//table[@id="edit-missing-module-list"]//td[text()="' . $available . '"]');
+    }
+
+    // Test the missing migration paths.
+    $all_missing = $this->getMissingPaths();
+    foreach ($all_missing as $missing) {
+      $this->assertSession()->elementExists('xpath', '//table[@id="edit-missing-module-list"]//td[text()="' . $missing . '"]');
+      $this->assertSession()->elementNotExists('xpath', '//table[@id="edit-available-module-list-module-list"]//td[text()="' . $missing . '"]');
+    }
+
     $this->drupalPostForm(NULL, [], t('Perform upgrade'));
     $this->assertText(t('Congratulations, you upgraded Drupal!'));
 
@@ -259,4 +274,19 @@ protected function translatePostValues(array $values) {
    */
   abstract protected function getEntityCounts();
 
+  /**
+   * Gets the available upgrade paths.
+   *
+   * @return int[]
+   *   An array of expected counts keyed by entity type ID.
+   */
+  abstract protected function getAvailablePaths();
+
+  /**
+   * Gets the missing upgrade paths.
+   *
+   * @return int[]
+   *   An array of expected counts keyed by entity type ID.
+   */
+  abstract protected function getMissingPaths();
 }
only in patch2:
unchanged:
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
@@ -76,6 +76,72 @@ protected function getEntityCounts() {
   }
 
   /**
+   * {@inheritdoc}
+   */
+  public function getAvailablePaths() {
+    return [
+      'block',
+      'comment',
+      'contact',
+      'content',
+      'date',
+      'dblog',
+      'email',
+      'entityreference',
+      'file',
+      'filefield',
+      'filter',
+      'i18ntaxonomy',
+      'image',
+      'imagecache',
+      'imagefield',
+      'link',
+      'list',
+      'menu',
+      'node',
+      'node_reference',
+      'number',
+      'options',
+      'optionwidgets',
+      'path',
+      'phone',
+      'profile',
+      'search',
+      'system',
+      'taxonomy',
+      'text',
+      'upload',
+      'user',
+      'user_reference',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getMissingPaths() {
+    return [
+      'aggregator',
+      'book',
+      'date_api',
+      'date_timezone',
+      'event',
+      'i18n',
+      'i18nblocks',
+      'i18ncck',
+      'i18ncontent',
+      'i18nmenu',
+      'i18nprofile',
+      'i18nstrings',
+      'imageapi',
+      'locale',
+      'php',
+      'translation',
+      'variable_admin',
+    ];
+  }
+
+  /**
    * Executes all steps of migrations upgrade.
    */
   public function testMigrateUpgrade() {
only in patch2:
unchanged:
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
@@ -82,6 +82,74 @@ protected function getEntityCounts() {
   }
 
   /**
+   * {@inheritdoc}
+   */
+  public function getAvailablePaths() {
+    return [
+      'block',
+      'comment',
+      'contact',
+      'date',
+      'dblog',
+      'email',
+      'entityreference',
+      'field',
+      'field_sql_storage',
+      'file',
+      'filefield',
+      'filter',
+      'image',
+      'imagefield',
+      'link',
+      'list',
+      'menu',
+      'node',
+      'node_reference',
+      'number',
+      'options',
+      'optionwidgets',
+      'path',
+      'phone',
+      'search',
+      'shortcut',
+      //'simpletest',
+      'system',
+      'taxonomy',
+      'text',
+      //'update',
+      'user',
+      'user_reference',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getMissingPaths() {
+    return [
+      'aggregator',
+      'blog',
+      'book',
+      'color',
+      'contextual',
+      'date_api',
+      'entity',
+      'field_ui',
+      'forum',
+      'help',
+      'locale',
+      'php',
+      'rdf',
+      'statistics',
+      'syslog',
+      'toolbar',
+      'tracker',
+      'translation',
+      'trigger',
+    ];
+  }
+
+  /**
    * Executes all steps of migrations upgrade.
    */
   public function testMigrateUpgrade() {