diff --git a/tests/src/Unit/ConfigListerTest.php b/tests/src/Unit/ConfigListerTest.php
index fe02004..5de70ca 100644
--- a/tests/src/Unit/ConfigListerTest.php
+++ b/tests/src/Unit/ConfigListerTest.php
@@ -258,7 +258,7 @@ class ConfigListerTest extends ConfigUpdateUnitTestBase {
     $values = [];
     foreach ($this->configProviderList as $provider => $info) {
       // Info has: [type, install storage item, optional storage item].
-      // Values needs: [item, [type, provider name]]
+      // Values needs: [item, [type, provider name]].
       $values[] = [$info[1], [$info[0], $provider]];
       $values[] = [$info[2], [$info[0], $provider]];
     }
diff --git a/tests/src/Unit/ConfigUpdateUnitTestBase.php b/tests/src/Unit/ConfigUpdateUnitTestBase.php
index b4c033d..054ccb0 100644
--- a/tests/src/Unit/ConfigUpdateUnitTestBase.php
+++ b/tests/src/Unit/ConfigUpdateUnitTestBase.php
@@ -10,7 +10,7 @@ use Drupal\Tests\UnitTestCase;
  *
  * This class provides some mock classes for unit testing.
  */
-class ConfigUpdateUnitTestBase extends UnitTestCase {
+abstract class ConfigUpdateUnitTestBase extends UnitTestCase {
 
   /**
    * The mocked entity definition information.
@@ -18,9 +18,9 @@ class ConfigUpdateUnitTestBase extends UnitTestCase {
    * They are not sorted, to test that the methods sort them. Also there are a
    * couple with prefixes that are subsets of each other.
    *
-   * @see ConfigUpdateUnitTestBase::getEntityManagerMock().
-   *
    * @var string[]
+   *
+   * @see ConfigUpdateUnitTestBase::getEntityManagerMock().
    */
   protected $entityDefinitionInformation = [
     ['prefix' => 'foo.bar', 'type' => 'foo'],
@@ -74,9 +74,9 @@ class ConfigUpdateUnitTestBase extends UnitTestCase {
    * Array structure: Each element is an array whose first element is a
    * provider name, and second is an array of config items it provides.
    *
-   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
-   *
    * @var array
+   *
+   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
    */
   protected $configStorageActiveInfo = [
     ['foo.bar', ['foo.bar.one', 'foo.bar.two', 'foo.bar.three']],
@@ -102,8 +102,9 @@ class ConfigUpdateUnitTestBase extends UnitTestCase {
    * Array structure: Each element is an array whose first element is a
    * provider name, and second is an array of config items it provides.
    *
-   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
    * @var array
+   *
+   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
    */
   protected $configStorageExtensionInfo = [
     ['foo.bar', ['foo.bar.one', 'foo.bar.two', 'foo.bar.seven']],
@@ -128,8 +129,9 @@ class ConfigUpdateUnitTestBase extends UnitTestCase {
    * Array structure: Each element is an array whose first element is a
    * provider name, and second is an array of config items it provides.
    *
-   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
    * @var array
+   *
+   * @see ConfigUpdateUnitTestBase::getConfigStorageMock()
    */
   protected $configStorageOptionalInfo = [
     ['foo.bar', []],