diff --git a/core/includes/schema.inc b/core/includes/schema.inc
index 4712d3be10e..aa3984b91ac 100644
--- a/core/includes/schema.inc
+++ b/core/includes/schema.inc
@@ -74,7 +74,7 @@ function drupal_get_schema_versions($module) {
  *   module is not installed.
  */
 function drupal_get_installed_schema_version($module, $reset = FALSE, $array = FALSE) {
-  static $versions = array();
+  $versions = &drupal_static(__FUNCTION__, array());
 
   if ($reset) {
     $versions = array();
diff --git a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
index 7eb5c100fb0..702fdb2527c 100644
--- a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
+++ b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
@@ -192,6 +192,8 @@ abstract class UpdatePathTestBase extends WebTestBase {
     $this->container = \Drupal::getContainer();
 
     $this->replaceUser1();
+
+    require_once \Drupal::root() . '/core/includes/update.inc';
   }
 
   /**
@@ -251,6 +253,28 @@ abstract class UpdatePathTestBase extends WebTestBase {
     if ($this->checkFailedUpdates) {
       $this->assertNoRaw('<strong>' . t('Failed:') . '</strong>');
 
+      // Ensure that there are no pending updates.
+      foreach (['update', 'post_update'] as $update_type) {
+        switch ($update_type) {
+          case 'update':
+            $all_updates = update_get_update_list();
+            break;
+          case 'post_update':
+            $all_updates = \Drupal::service('update.post_update_registry')->getPendingUpdateInformation();
+            break;
+        }
+        foreach ($all_updates as $module => $updates) {
+          if (!empty($updates['pending'])) {
+            foreach (array_keys($updates['pending']) as $update_name) {
+              $this->fail("The $update_name() update function from the $module module did not run.");
+            }
+          }
+        }
+      }
+      // Reset the static cache of drupal_get_installed_schema_version() so that
+      // more complex update path testing works.
+      drupal_static_reset('drupal_get_installed_schema_version');
+
       // The config schema can be incorrect while the update functions are being
       // executed. But once the update has been completed, it needs to be valid
       // again. Assert the schema of all configuration objects now.