Nikolay Shapovalov
--- a/tests/src/Functional/CorePagerReplaceTest.php
+++ b/tests/src/Functional/CorePagerReplaceTest.php
-    // Insert 300 log messages.
-    $logger = $this->container->get('logger.factory')->get('pager_test');
-    for ($i = 0; $i < 300; $i++) {
-      $logger->debug($this->randomString());
-    }
-
-    $this->drupalLogin($this->drupalCreateUser([
-      'access site reports',
-      'administer image styles',
-      'administer site configuration',
-    ]));
+    // Grant new permission for admin user role.
+    $roles = $this->adminUser->getRoles(TRUE);
+    Role::load(reset($roles))
+      ->grantPermission('administer site configuration')
+      ->save();
--- a/src/Plugin/pagerer/PagererStyleBase.php
+++ b/src/Plugin/pagerer/PagererStyleBase.php
    ];
  }

+  /**
+   * Return the pager render array.
+   *
+   * @return array
+   *   render array.
+   */
+  abstract protected function buildPagerItems();