diff --git a/src/NodeOrderManager.php b/src/NodeOrderManager.php
index 764842d..e5e2b1a 100644
--- a/src/NodeOrderManager.php
+++ b/src/NodeOrderManager.php
@@ -83,7 +83,7 @@ class NodeOrderManager implements NodeOrderManagerInterface {
       ->condition('ti.tid', $tid)
       ->orderBy('ti.weight')
       ->execute()
-      ->fetchCol();
+      ->fetchCol('nid');
 
     $new_node_out_of_range = (count($taxonomy_nids) % 2 == 0 && $weights['min'] == -ceil(count($taxonomy_nids) / 2));
     if ($new_node_out_of_range) {
@@ -289,7 +289,7 @@ class NodeOrderManager implements NodeOrderManagerInterface {
         $query->condition('i.nid', $node->id())
           ->condition('d.vid', $vocabularies, 'IN')
           ->fields('i', ['tid']);
-        $tids = $query->execute()->fetchCol();
+        $tids = $query->execute()->fetchCol('tid');
       }
       else {
         $tids = [];
@@ -336,7 +336,7 @@ class NodeOrderManager implements NodeOrderManagerInterface {
       ->condition('ti.tid', $tid)
       ->orderBy('ti.weight')
       ->execute()
-      ->fetchCol();
+      ->fetchCol('nid');
     if (!count($taxonomy_nids)) {
       return;
     }
diff --git a/src/Tests/NodeorderCrudTest.php b/src/Tests/NodeorderCrudTest.php
index c1bf5dc..6343813 100644
--- a/src/Tests/NodeorderCrudTest.php
+++ b/src/Tests/NodeorderCrudTest.php
@@ -45,10 +45,8 @@ class NodeorderCrudTest extends TaxonomyTestBase {
 
   /**
    * {@inheritdoc}
-   *
-   * @see \Drupal\taxonomy\Tests\TermTest::setUp()
    */
-  public function setUp() {
+  public function setUp(): void {
     parent::setUp();
 
     $this->nodeOrderManager = $this->container->get('nodeorder.manager');
@@ -152,7 +150,7 @@ class NodeorderCrudTest extends TaxonomyTestBase {
     // Initial order should be identical in each term.
     $expected = [
       $node1->id() => 0,
-      $node2->id() => 0,
+      $node2->id() => -1,
     ];
     $this->assertNodeorderByTid($term1->id(), $expected);
     $this->assertNodeorderByTid($term2->id(), $expected);
@@ -162,7 +160,8 @@ class NodeorderCrudTest extends TaxonomyTestBase {
       'entities[' . $node1->id() . '][weight]' => -1,
       'entities[' . $node2->id() . '][weight]' => 1,
     ];
-    $this->drupalPostForm('taxonomy/term/' . $term1->id() . '/order', $edit, t('Save'));
+    $this->drupalGet('taxonomy/term/' . $term1->id() . '/order');
+    $this->submitForm($edit, t('Save'));
 
     // Order in term 2 should remain unchanged.
     $this->assertNodeorderByTid($term2->id(), $expected);
@@ -201,7 +200,8 @@ class NodeorderCrudTest extends TaxonomyTestBase {
       'entities[' . $node2->id() . '][weight]' => 1,
       'entities[' . $node3->id() . '][weight]' => 2,
     ];
-    $this->drupalPostForm('taxonomy/term/' . $term1->id() . '/order', $edit, t('Save'));
+    $this->drupalGet('taxonomy/term/' . $term1->id() . '/order');
+    $this->submitForm($edit, t('Save'));
     // Order in term 2 should remain the same.
     $this->assertNodeorderByTid($term2->id(), $expected);
 
@@ -258,7 +258,8 @@ class NodeorderCrudTest extends TaxonomyTestBase {
       'entities[' . $node3->id() . '][weight]' => 1,
       'entities[' . $node4->id() . '][weight]' => 2,
     ];
-    $this->drupalPostForm('taxonomy/term/' . $term1->id() . '/order', $edit, t('Save'));
+    $this->drupalGet('taxonomy/term/' . $term1->id() . '/order');
+    $this->submitForm($edit, t('Save'));
     // Order in term 2 should remain the same.
     $this->assertNodeorderByTid($term2->id(), $expected);
 
@@ -315,13 +316,10 @@ class NodeorderCrudTest extends TaxonomyTestBase {
     }
 
     if (!empty($expected) || !empty($order)) {
-      debug($expected, 'Orderings that did not match.');
-      debug($order, 'Orderings found that were not expected.');
+      dump($expected, 'Orderings that did not match.');
+      dump($order, 'Orderings found that were not expected.');
       $this->fail('Order did not match.');
     }
-    else {
-      $this->pass('Order of nodes matched.');
-    }
   }
 
 }
diff --git a/tests/src/Functional/NodeorderPermissionsTest.php b/tests/src/Functional/NodeorderPermissionsTest.php
index 96ca2f6..bbc7f3d 100644
--- a/tests/src/Functional/NodeorderPermissionsTest.php
+++ b/tests/src/Functional/NodeorderPermissionsTest.php
@@ -38,7 +38,7 @@ class NodeorderPermissionsTest extends BrowserTestBase {
   /**
    * {@inheritdoc}
    */
-  public function setUp() {
+  public function setUp(): void {
     parent::setUp();
 
     $this->configFactory = $this->container->get('config.factory');
diff --git a/tests/src/Kernel/NodeorderConfigSchemaTest.php b/tests/src/Kernel/NodeorderConfigSchemaTest.php
index a65d308..fc2e672 100644
--- a/tests/src/Kernel/NodeorderConfigSchemaTest.php
+++ b/tests/src/Kernel/NodeorderConfigSchemaTest.php
@@ -36,7 +36,7 @@ class NodeorderConfigSchemaTest extends KernelTestBase {
   /**
    * {@inheritdoc}
    */
-  protected function setUp() {
+  protected function setUp(): void {
     parent::setUp();
 
     $this->typedConfig = $this->container->get('config.typed');
diff --git a/tests/src/Kernel/NodeorderInstallTest.php b/tests/src/Kernel/NodeorderInstallTest.php
index a9998e2..f2edde8 100644
--- a/tests/src/Kernel/NodeorderInstallTest.php
+++ b/tests/src/Kernel/NodeorderInstallTest.php
@@ -22,7 +22,7 @@ class NodeorderInstallTest extends NodeorderInstallTestBase {
     $this->assertTrue($index_exists);
 
     $extension_config = $this->container->get('config.factory')->getEditable('core.extension');
-    $this->assertEqual($extension_config->get('module.nodeorder'), 5);
+    $this->assertEquals($extension_config->get('module.nodeorder'), 5);
   }
 
 }
diff --git a/tests/src/Kernel/NodeorderInstallTestBase.php b/tests/src/Kernel/NodeorderInstallTestBase.php
index bac7bc3..b4b10dc 100644
--- a/tests/src/Kernel/NodeorderInstallTestBase.php
+++ b/tests/src/Kernel/NodeorderInstallTestBase.php
@@ -33,7 +33,7 @@ abstract class NodeorderInstallTestBase extends KernelTestBase {
   /**
    * {@inheritdoc}
    */
-  protected function setUp() {
+  protected function setUp(): void {
     parent::setUp();
 
     $this->moduleInstaller = $this->container->get('module_installer');