diff --git a/core/modules/system/tests/modules/form_test/form_test.module b/core/modules/system/tests/modules/form_test/form_test.module
index de5c2f0..a9c585e 100644
--- a/core/modules/system/tests/modules/form_test/form_test.module
+++ b/core/modules/system/tests/modules/form_test/form_test.module
@@ -419,134 +419,6 @@ function _form_test_tableselect_form_builder($form, $form_state, $element_proper
 }
 
 /**
- * Test the tableselect #multiple = TRUE functionality.
- *
- * @deprecated Use \Drupal\form_test\testTableSelectCheckboxes()
- */
-function _form_test_tableselect_multiple_true_form($form, $form_state) {
-  return _form_test_tableselect_form_builder($form, $form_state, array('#multiple' => TRUE));
-}
-
-/**
- * Process the tableselect #multiple = TRUE submitted values.
- */
-function _form_test_tableselect_multiple_true_form_submit($form, &$form_state) {
-  $selected = $form_state['values']['tableselect'];
-  foreach ($selected as $key => $value) {
-    drupal_set_message(t('Submitted: @key = @value', array('@key' => $key, '@value' => $value)));
-  }
-}
-
-/**
- * Test the tableselect #multiple = FALSE functionality.
- *
- * @deprecated Use \Drupal\form_test\testTableSelectRadios()
- */
-function _form_test_tableselect_multiple_false_form($form, $form_state) {
-  return _form_test_tableselect_form_builder($form, $form_state, array('#multiple' => FALSE));
-}
-
-/**
- * Test the tableselect #colspan functionality.
- *
- * @deprecated Use \Drupal\form_test\testTableSelectColspan()
- */
-function _form_test_tableselect_colspan_form($form, $form_state) {
-  list($header, $options) = _form_test_tableselect_get_data();
-
-  // Change the data so that the third column has colspan=2.
-  $header['three'] = array('data' => 'Three', 'colspan' => 2);
-  unset($header['four']);
-  // Set the each row so that column 3 is an array.
-  foreach ($options as $name => $row) {
-    $options[$name]['three'] = array($row['three'], $row['four']);
-    unset($options[$name]['four']);
-  }
-  // Combine cells in row 3.
-  $options['row3']['one'] = array('data' => $options['row3']['one'], 'colspan' => 2);
-  unset($options['row3']['two']);
-  $options['row3']['three'] = array('data' => $options['row3']['three'][0], 'colspan' => 2);
-  unset($options['row3']['four']);
-
-  return _form_test_tableselect_form_builder($form, $form_state, array('#header' => $header, '#options' => $options));
-}
-
-/**
- * Process the tableselect #multiple = FALSE submitted values.
- */
-function _form_test_tableselect_multiple_false_form_submit($form, &$form_state) {
-  drupal_set_message(t('Submitted: @value', array('@value' => $form_state['values']['tableselect'])));
-}
-
-/**
- * Test functionality of the tableselect #empty property.
- *
- * @deprecated Use \Drupal\form_test\testTableSelectEmptyText()
- */
-function _form_test_tableselect_empty_form($form, $form_state) {
-  return _form_test_tableselect_form_builder($form, $form_state, array('#options' => array()));
-}
-
-/**
- * Test functionality of the tableselect #js_select property.
- *
- * @deprecated Use \Drupal\form_test\testTableSelectJS()
- */
-function _form_test_tableselect_js_select_form($form, $form_state, $action) {
-  switch ($action) {
-    case 'multiple-true-default':
-      $options = array('#multiple' => TRUE);
-      break;
-
-    case 'multiple-false-default':
-      $options = array('#multiple' => FALSE);
-      break;
-
-    case 'multiple-true-no-advanced-select':
-      $options = array('#multiple' => TRUE, '#js_select' => FALSE);
-      break;
-
-    case 'multiple-false-advanced-select':
-      $options = array('#multiple' => FALSE, '#js_select' => TRUE);
-      break;
-  }
-
-  return _form_test_tableselect_form_builder($form, $form_state, $options);
-}
-
-/**
- * Tests functionality of vertical tabs.
- *
- * @deprecated Use \Drupal\form_test\testVerticalTabs()
- */
-function _form_test_vertical_tabs_form($form, &$form_state) {
-  $form['vertical_tabs'] = array(
-    '#type' => 'vertical_tabs',
-  );
-  $form['tab1'] = array(
-    '#type' => 'details',
-    '#title' => t('Tab 1'),
-    '#group' => 'vertical_tabs',
-    '#access' => user_access('access vertical_tab_test tabs'),
-  );
-  $form['tab1']['field1'] = array(
-    '#title' => t('Field 1'),
-    '#type' => 'textfield',
-  );
-  $form['tab2'] = array(
-    '#type' => 'details',
-    '#title' => t('Tab 2'),
-    '#group' => 'vertical_tabs',
-    '#access' => user_access('access vertical_tab_test tabs'),
-  );
-  $form['tab2']['field2'] = array(
-    '#title' => t('Field 2'),
-    '#type' => 'textfield',
-  );
-  return $form;
-}
-
-/**
  * A multistep form for testing the form storage.
  *
  * It uses two steps for editing a virtual "thing". Any changes to it are saved
@@ -802,77 +674,6 @@ function form_test_form_state_values_clean_advanced_form_submit($form, &$form_st
 }
 
 /**
- * Build a form to test a checkbox.
- *
- * @deprecated Use \Drupal\form_test\testCheckbox()
- */
-function _form_test_checkbox($form, &$form_state) {
-  $form['#submit'] = array('_form_test_submit_values_json');
-
-  // A required checkbox.
-  $form['required_checkbox'] = array(
-    '#type' => 'checkbox',
-    '#required' => TRUE,
-    '#title' => 'required_checkbox',
-  );
-
-  // A disabled checkbox should get its default value back.
-  $form['disabled_checkbox_on'] = array(
-    '#type' => 'checkbox',
-    '#disabled' => TRUE,
-    '#return_value' => 'disabled_checkbox_on',
-    '#default_value' => 'disabled_checkbox_on',
-    '#title' => 'disabled_checkbox_on',
-  );
-  $form['disabled_checkbox_off'] = array(
-    '#type' => 'checkbox',
-    '#disabled' => TRUE,
-    '#return_value' => 'disabled_checkbox_off',
-    '#default_value' => NULL,
-    '#title' => 'disabled_checkbox_off',
-  );
-
-  // A checkbox is active when #default_value == #return_value.
-  $form['checkbox_on'] = array(
-    '#type' => 'checkbox',
-    '#return_value' => 'checkbox_on',
-    '#default_value' => 'checkbox_on',
-    '#title' => 'checkbox_on',
-  );
-
-  // But inactive in any other case.
-  $form['checkbox_off'] = array(
-    '#type' => 'checkbox',
-    '#return_value' => 'checkbox_off',
-    '#default_value' => 'checkbox_on',
-    '#title' => 'checkbox_off',
-  );
-
-  // Checkboxes with a #return_value of '0' are supported.
-  $form['zero_checkbox_on'] = array(
-    '#type' => 'checkbox',
-    '#return_value' => '0',
-    '#default_value' => '0',
-    '#title' => 'zero_checkbox_on',
-  );
-
-  // In that case, passing a #default_value != '0' means that the checkbox is off.
-  $form['zero_checkbox_off'] = array(
-    '#type' => 'checkbox',
-    '#return_value' => '0',
-    '#default_value' => '1',
-    '#title' => 'zero_checkbox_off',
-  );
-
-  $form['submit'] = array(
-    '#type' => 'submit',
-    '#value' => t('Submit')
-  );
-
-  return $form;
-}
-
-/**
  * Builds a form to test #type 'select' validation.
  *
  * @deprecated Use \Drupal\form_test\testSelect()
@@ -1587,31 +1388,6 @@ function _form_test_disabled_elements($form, &$form_state) {
 }
 
 /**
- * Build a form to test input forgery of enabled elements.
- *
- * @deprecated Use \Drupal\form_test\testInputForgery()
- */
-function _form_test_input_forgery($form, &$form_state) {
-  $form['#submit'] = array('_form_test_submit_values_json');
-
-  // For testing that a user can't submit a value not matching one of the
-  // allowed options.
-  $form['checkboxes'] = array(
-    '#title' => t('Checkboxes'),
-    '#type' => 'checkboxes',
-    '#options' => array(
-      'one' => 'One',
-      'two' => 'Two',
-    ),
-  );
-  $form['submit'] = array(
-    '#type' => 'submit',
-    '#value' => t('Submit'),
-  );
-  return $form;
-}
-
-/**
  * Form builder for testing preservation of values during a rebuild.
  *
  * @deprecated Use \Drupal\form_test\testRebuildPreservation()
diff --git a/core/modules/system/tests/modules/form_test/form_test.routing.yml b/core/modules/system/tests/modules/form_test/form_test.routing.yml
index 3540177..3734665 100644
--- a/core/modules/system/tests/modules/form_test/form_test.routing.yml
+++ b/core/modules/system/tests/modules/form_test/form_test.routing.yml
@@ -119,7 +119,7 @@ form_test.pattern:
 form_test.tableselect_checkboxes:
   path: '/form_test/tableselect/multiple-true'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectCheckboxes'
+    _form: '\Drupal\form_test\FormTestTableSelectMultipleTrueForm'
     _title: 'Tableselect checkboxes test'
   requirements:
     _access: 'TRUE'
@@ -127,7 +127,7 @@ form_test.tableselect_checkboxes:
 form_test.tableselect_radios:
   path: '/form_test/tableselect/multiple-false'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectRadios'
+    _form: '\Drupal\form_test\FormTestTableSelectMultipleFalseForm'
     _title: 'Tableselect radio button test'
   requirements:
     _access: 'TRUE'
@@ -135,7 +135,7 @@ form_test.tableselect_radios:
 form_test.tableselect_colspan:
   path: '/form_test/tableselect/colspan'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectColspan'
+    _form: '\Drupal\form_test\FormTestTableSelectColspanForm'
     _title: 'Tableselect colspan test'
   requirements:
     _access: 'TRUE'
@@ -143,7 +143,7 @@ form_test.tableselect_colspan:
 form_test.tableselect_empty_text:
   path: '/form_test/tableselect/empty-text'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectEmptyText'
+    _form: '\Drupal\form_test\FormTestTableSelectEmptyForm'
     _title: 'Tableselect empty text test'
   requirements:
     _access: 'TRUE'
@@ -151,7 +151,7 @@ form_test.tableselect_empty_text:
 form_test.tableselect_js:
   path: '/form_test/tableselect/advanced-select/{test_action}'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectJS'
+    _form: '\Drupal\form_test\FormTestTableSelectJsSelectForm'
     _title: 'Tableselect js_select tests'
   requirements:
     _access: 'TRUE'
@@ -159,7 +159,7 @@ form_test.tableselect_js:
 form_test.vertical_tabs:
   path: '/form_test/vertical-tabs'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testVerticalTabs'
+    _form: '\Drupal\form_test\FormTestVerticalTabsForm'
     _title: 'Vertical tabs tests'
   requirements:
     _access: 'TRUE'
@@ -191,7 +191,7 @@ form_test.state_clean_advanced:
 form_test.checkbox:
   path: '/form-test/checkbox'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testCheckbox'
+    _form: '\Drupal\form_test\FormTestCheckboxForm'
     _title: 'Form test'
   requirements:
     _access: 'TRUE'
@@ -304,7 +304,7 @@ form_test.disabled_elements:
 form_test.input_forgery:
   path: '/form-test/input-forgery'
   defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testInputForgery'
+    _form: '\Drupal\form_test\FormTestInputForgeryForm'
     _title: 'Form test'
   requirements:
     _access: 'TRUE'
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestCheckboxForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestCheckboxForm.php
new file mode 100644
index 0000000..1caa231
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestCheckboxForm.php
@@ -0,0 +1,95 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestCheckboxForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestCheckboxForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_test_checkbox_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    $form['#submit'] = array('_form_test_submit_values_json');
+
+    // A required checkbox.
+    $form['required_checkbox'] = array(
+      '#type' => 'checkbox',
+      '#required' => TRUE,
+      '#title' => 'required_checkbox',
+    );
+
+    // A disabled checkbox should get its default value back.
+    $form['disabled_checkbox_on'] = array(
+      '#type' => 'checkbox',
+      '#disabled' => TRUE,
+      '#return_value' => 'disabled_checkbox_on',
+      '#default_value' => 'disabled_checkbox_on',
+      '#title' => 'disabled_checkbox_on',
+    );
+    $form['disabled_checkbox_off'] = array(
+      '#type' => 'checkbox',
+      '#disabled' => TRUE,
+      '#return_value' => 'disabled_checkbox_off',
+      '#default_value' => NULL,
+      '#title' => 'disabled_checkbox_off',
+    );
+
+    // A checkbox is active when #default_value == #return_value.
+    $form['checkbox_on'] = array(
+      '#type' => 'checkbox',
+      '#return_value' => 'checkbox_on',
+      '#default_value' => 'checkbox_on',
+      '#title' => 'checkbox_on',
+    );
+
+    // But inactive in any other case.
+    $form['checkbox_off'] = array(
+      '#type' => 'checkbox',
+      '#return_value' => 'checkbox_off',
+      '#default_value' => 'checkbox_on',
+      '#title' => 'checkbox_off',
+    );
+
+    // Checkboxes with a #return_value of '0' are supported.
+    $form['zero_checkbox_on'] = array(
+      '#type' => 'checkbox',
+      '#return_value' => '0',
+      '#default_value' => '0',
+      '#title' => 'zero_checkbox_on',
+    );
+
+    // In that case, passing a #default_value != '0'
+    // means that the checkbox is off.
+    $form['zero_checkbox_off'] = array(
+      '#type' => 'checkbox',
+      '#return_value' => '0',
+      '#default_value' => '1',
+      '#title' => 'zero_checkbox_off',
+    );
+
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => t('Submit'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestInputForgeryForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestInputForgeryForm.php
new file mode 100644
index 0000000..43ab396
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestInputForgeryForm.php
@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal/form_test/FormTestInputForgeryForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestInputForgeryForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_input_forgery';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    $form['#submit'] = array('_form_test_submit_values_json');
+
+    // For testing that a user can't submit a value not matching one of the
+    // allowed options.
+    $form['checkboxes'] = array(
+      '#title' => t('Checkboxes'),
+      '#type' => 'checkboxes',
+      '#options' => array(
+        'one' => 'One',
+        'two' => 'Two',
+      ),
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => t('Submit'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectColspanForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectColspanForm.php
new file mode 100644
index 0000000..e27117a
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectColspanForm.php
@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestTableSelectColspanForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestTableSelectColspanForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_tableselect_colspan_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    list($header, $options) = _form_test_tableselect_get_data();
+
+    // Change the data so that the third column has colspan=2.
+    $header['three'] = array('data' => 'Three', 'colspan' => 2);
+    unset($header['four']);
+    // Set the each row so that column 3 is an array.
+    foreach ($options as $name => $row) {
+      $options[$name]['three'] = array($row['three'], $row['four']);
+      unset($options[$name]['four']);
+    }
+    // Combine cells in row 3.
+    $options['row3']['one'] = array('data' => $options['row3']['one'], 'colspan' => 2);
+    unset($options['row3']['two']);
+    $options['row3']['three'] = array('data' => $options['row3']['three'][0], 'colspan' => 2);
+    unset($options['row3']['four']);
+
+    return _form_test_tableselect_form_builder($form, $form_state, array('#header' => $header, '#options' => $options));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectEmptyForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectEmptyForm.php
new file mode 100644
index 0000000..dd91a08
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectEmptyForm.php
@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FromTestTableselectEmptyForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestTableSelectEmptyForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_tableselect_empty_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    return _form_test_tableselect_form_builder($form, $form_state, array('#options' => array()));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectJsSelectForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectJsSelectForm.php
new file mode 100644
index 0000000..cc0292f
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectJsSelectForm.php
@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestTableSelectJsSelectForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Component\Utility\String;
+
+class FormTestTableSelectJsSelectForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_tableselect_js_select_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state, $test_action = NULL) {
+    switch (String::checkPlain($test_action)) {
+      case 'multiple-true-default':
+        $options = array('#multiple' => TRUE);
+        break;
+
+      case 'multiple-false-default':
+        $options = array('#multiple' => FALSE);
+        break;
+
+      case 'multiple-true-no-advanced-select':
+        $options = array('#multiple' => TRUE, '#js_select' => FALSE);
+        break;
+
+      case 'multiple-false-advanced-select':
+        $options = array('#multiple' => FALSE, '#js_select' => TRUE);
+        break;
+    }
+
+    return _form_test_tableselect_form_builder($form, $form_state, $options);;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleFalseForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleFalseForm.php
new file mode 100644
index 0000000..dcfcefc
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleFalseForm.php
@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestTableSelectMultipleFalseForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestTableSelectMultipleFalseForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_tableselect_multiple_false_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    return _form_test_tableselect_form_builder($form, $form_state, array('#multiple' => FALSE));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+    drupal_set_message(t('Submitted: @value', array('@value' => $form_state['values']['tableselect'])));
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleTrueForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleTrueForm.php
new file mode 100644
index 0000000..6aed259
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestTableSelectMultipleTrueForm.php
@@ -0,0 +1,36 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestTableSelectMultipleTrueForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestTableSelectMultipleTrueForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_tableselect_multiple_true_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    return _form_test_tableselect_form_builder($form, $form_state, array('#multiple' => TRUE));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+    $selected = $form_state['values']['tableselect'];
+    foreach ($selected as $key => $value) {
+      drupal_set_message(t('Submitted: @key = @value', array('@key' => $key, '@value' => $value)));
+    }
+  }
+}
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestVerticalTabsForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestVerticalTabsForm.php
new file mode 100644
index 0000000..0e08e76
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/FormTestVerticalTabsForm.php
@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\form_test\FormTestVerticalTabsForm.
+ */
+
+namespace Drupal\form_test;
+
+use Drupal\Core\Form\FormBase;
+
+class FormTestVerticalTabsForm extends FormBase {
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return '_form_test_vertical_tabs_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state) {
+    $form['vertical_tabs'] = array(
+      '#type' => 'vertical_tabs',
+    );
+    $form['tab1'] = array(
+      '#type' => 'details',
+      '#title' => t('Tab 1'),
+      '#group' => 'vertical_tabs',
+      '#access' => \Drupal::currentUser()->hasPermission('access vertical_tab_test tabs'),
+    );
+    $form['tab1']['field1'] = array(
+      '#title' => t('Field 1'),
+      '#type' => 'textfield',
+    );
+    $form['tab2'] = array(
+      '#type' => 'details',
+      '#title' => t('Tab 2'),
+      '#group' => 'vertical_tabs',
+      '#access' => \Drupal::currentUser()->hasPermission('access vertical_tab_test tabs'),
+    );
+    $form['tab2']['field2'] = array(
+      '#title' => t('Field 2'),
+      '#type' => 'textfield',
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}