form_test.module

<?php

/**
 * @file
 * Helper module for the form API tests.
 */

/**
 * Implements hook_menu().
 */
function form_test_menu() {
  $items['form-test/alter'] = array(
    'title' => 'Form altering test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_alter_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form-test/validate'] = array(
    'title' => 'Form validation handlers test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_validate_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form-test/validate-required'] = array(
    'title' => 'Form #required validation',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_validate_required_form',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/validate-required-no-title'] = array(
    'title' => 'Form #required validation without #title',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_validate_required_form_no_title',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/validate-no-token'] = array(
    'title' => 'Form validation without a CSRF token',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_validate_no_token',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/limit-validation-errors'] = array(
    'title' => 'Form validation with some error suppression',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_limit_validation_errors_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/tableselect/multiple-true'] = array(
    'title' => 'Tableselect checkboxes test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_tableselect_multiple_true_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/tableselect/multiple-false'] = array(
    'title' => 'Tableselect radio button test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_tableselect_multiple_false_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/tableselect/empty-text'] = array(
    'title' => 'Tableselect empty text test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_tableselect_empty_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/tableselect/advanced-select'] = array(
    'title' => 'Tableselect js_select tests',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_tableselect_js_select_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/vertical-tabs'] = array(
    'title' => 'Vertical tabs tests',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_vertical_tabs_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-storage'] = array(
    'title' => 'Form storage test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_storage_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-storage-legacy'] = array(
    'title' => 'Emulate legacy AHAH-style ajax callback',
    'page callback' => 'form_test_storage_legacy_handler',
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-storage-page-cache'] = array(
    'title' => 'Form storage with page cache test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_storage_page_cache_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/wrapper-callback'] = array(
    'title' => 'Form wrapper callback test',
    'page callback' => 'form_test_wrapper_callback',
    'page arguments' => array(
      'form_test_wrapper_callback_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-state-values-clean'] = array(
    'title' => 'Form state values clearance test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_form_state_values_clean_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-state-values-clean-advanced'] = array(
    'title' => 'Form state values clearance advanced test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_form_state_values_clean_advanced_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form-test/checkbox'] = array(
    'title' => t('Form test'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_checkbox',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/select'] = array(
    'title' => t('Select'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_select',
    ),
    'access callback' => TRUE,
  );
  $items['form-test/checkboxes-radios'] = array(
    'title' => t('Checkboxes, Radios'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_checkboxes_radios',
    ),
    'access callback' => TRUE,
  );
  $items['form-test/disabled-elements'] = array(
    'title' => t('Form test'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_disabled_elements',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/input-forgery'] = array(
    'title' => t('Form test'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      '_form_test_input_forgery',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/form-rebuild-preserve-values'] = array(
    'title' => 'Form values preservation during rebuild test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_form_rebuild_preserve_values_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form-test/redirect'] = array(
    'title' => 'Redirect test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_redirect',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form_test/form-labels'] = array(
    'title' => 'Form label test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_label_test_form',
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['form-test/state-persist'] = array(
    'title' => 'Form state persistence without storage',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_state_persist',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/clicked-button'] = array(
    'title' => 'Clicked button test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_clicked_button',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  if (module_exists('node')) {
    $items['form-test/two-instances-of-same-form'] = array(
      'title' => 'AJAX test with two form instances',
      'page callback' => 'form_test_two_instances',
      'access callback' => 'node_access',
      'access arguments' => array(
        'create',
        'page',
      ),
      'file path' => drupal_get_path('module', 'node'),
      'file' => 'node.pages.inc',
      'type' => MENU_CALLBACK,
    );
  }
  $items['form-test/double-form'] = array(
    'title' => 'Double form test',
    'page callback' => 'form_test_double_form',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/load-include-menu'] = array(
    'title' => 'FAPI test loading includes',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_load_include_menu',
    ),
    'access callback' => TRUE,
    'file' => 'form_test.file.inc',
    'type' => MENU_CALLBACK,
  );
  $items['form-test/load-include-custom'] = array(
    'title' => 'FAPI test loading includes',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_load_include_custom',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['form-test/checkboxes-zero'] = array(
    'title' => 'FAPI test involving checkboxes and zero',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'form_test_checkboxes_zero',
    ),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Form submit handler to return form values as JSON.
 */
function _form_test_submit_values_json($form, &$form_state) {
  drupal_json_output($form_state['values']);
  drupal_exit();
}

/**
 * Form builder for testing hook_form_alter() and hook_form_FORM_ID_alter().
 */
function form_test_alter_form($form, &$form_state) {

  // Elements can be added as needed for future testing needs, but for now,
  // we're only testing alter hooks that do not require any elements added by
  // this function.
  return $form;
}

/**
 * Implements hook_form_FORM_ID_alter() on behalf of block.module.
 */
function block_form_form_test_alter_form_alter(&$form, &$form_state) {
  drupal_set_message('block_form_form_test_alter_form_alter() executed.');
}

/**
 * Implements hook_form_alter().
 */
function form_test_form_alter(&$form, &$form_state, $form_id) {
  if ($form_id == 'form_test_alter_form') {
    drupal_set_message('form_test_form_alter() executed.');
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function form_test_form_form_test_alter_form_alter(&$form, &$form_state) {
  drupal_set_message('form_test_form_form_test_alter_form_alter() executed.');
}

/**
 * Implements hook_form_FORM_ID_alter() on behalf of system.module.
 */
function system_form_form_test_alter_form_alter(&$form, &$form_state) {
  drupal_set_message('system_form_form_test_alter_form_alter() executed.');
}

/**
 * Form builder for testing drupal_validate_form().
 *
 * Serves for testing form processing and alterations by form validation
 * handlers, especially for the case of a validation error:
 * - form_set_value() should be able to alter submitted values in
 *   $form_state['values'] without affecting the form element.
 * - #element_validate handlers should be able to alter the $element in the form
 *   structure and the alterations should be contained in the rebuilt form.
 * - #validate handlers should be able to alter the $form and the alterations
 *   should be contained in the rebuilt form.
 */
function form_test_validate_form($form, &$form_state) {
  $form['name'] = array(
    '#type' => 'textfield',
    '#title' => 'Name',
    '#default_value' => '',
    '#element_validate' => array(
      'form_test_element_validate_name',
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );

  // To simplify this test, enable form caching and use form storage to
  // remember our alteration.
  $form_state['cache'] = TRUE;
  return $form;
}

/**
 * Form element validation handler for 'name' in form_test_validate_form().
 */
function form_test_element_validate_name(&$element, &$form_state) {
  $triggered = FALSE;
  if ($form_state['values']['name'] == 'element_validate') {

    // Alter the form element.
    $element['#value'] = '#value changed by #element_validate';

    // Alter the submitted value in $form_state.
    form_set_value($element, 'value changed by form_set_value() in #element_validate', $form_state);
    $triggered = TRUE;
  }
  if ($form_state['values']['name'] == 'element_validate_access') {
    $form_state['storage']['form_test_name'] = $form_state['values']['name'];

    // Alter the form element.
    $element['#access'] = FALSE;
    $triggered = TRUE;
  }
  elseif (!empty($form_state['storage']['form_test_name'])) {

    // To simplify this test, just take over the element's value into $form_state.
    form_set_value($element, $form_state['storage']['form_test_name'], $form_state);
    $triggered = TRUE;
  }
  if ($triggered) {

    // Output the element's value from $form_state.
    drupal_set_message(t('@label value: @value', array(
      '@label' => $element['#title'],
      '@value' => $form_state['values']['name'],
    )));

    // Trigger a form validation error to see our changes.
    form_set_error('');
  }
}

/**
 * Form validation handler for form_test_validate_form().
 */
function form_test_validate_form_validate(&$form, &$form_state) {
  if ($form_state['values']['name'] == 'validate') {

    // Alter the form element.
    $form['name']['#value'] = '#value changed by #validate';

    // Alter the submitted value in $form_state.
    form_set_value($form['name'], 'value changed by form_set_value() in #validate', $form_state);

    // Output the element's value from $form_state.
    drupal_set_message(t('@label value: @value', array(
      '@label' => $form['name']['#title'],
      '@value' => $form_state['values']['name'],
    )));

    // Trigger a form validation error to see our changes.
    form_set_error('');
  }
}

/**
 * Form constructor to test the #required property.
 */
function form_test_validate_required_form($form, &$form_state) {
  $options = drupal_map_assoc(array(
    'foo',
    'bar',
  ));
  $form['textfield'] = array(
    '#type' => 'textfield',
    '#title' => 'Textfield',
    '#required' => TRUE,
  );
  $form['checkboxes'] = array(
    '#type' => 'checkboxes',
    '#title' => 'Checkboxes',
    '#options' => $options,
    '#required' => TRUE,
  );
  $form['select'] = array(
    '#type' => 'select',
    '#title' => 'Select',
    '#options' => $options,
    '#required' => TRUE,
  );
  $form['radios'] = array(
    '#type' => 'radios',
    '#title' => 'Radios',
    '#options' => $options,
    '#required' => TRUE,
  );
  $form['radios_optional'] = array(
    '#type' => 'radios',
    '#title' => 'Radios (optional)',
    '#options' => $options,
  );
  $form['radios_optional_default_value_false'] = array(
    '#type' => 'radios',
    '#title' => 'Radios (optional, with a default value of FALSE)',
    '#options' => $options,
    '#default_value' => FALSE,
  );
  $form['actions'] = array(
    '#type' => 'actions',
  );
  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  return $form;
}

/**
 * Form submission handler for form_test_validate_required_form().
 */
function form_test_validate_required_form_submit($form, &$form_state) {
  drupal_set_message('The form_test_validate_required_form form was submitted successfully.');
}

/**
 * Form constructor to test the #required property without #title.
 */
function form_test_validate_required_form_no_title($form, &$form_state) {
  $form['textfield'] = array(
    '#type' => 'textfield',
    '#required' => TRUE,
  );
  $form['actions'] = array(
    '#type' => 'actions',
  );
  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  return $form;
}

/**
 * Form submission handler for form_test_validate_required_form_no_title().
 */
function form_test_validate_required_form_no_title_submit($form, &$form_state) {
  drupal_set_message('The form_test_validate_required_form_no_title form was submitted successfully.');
}

/**
 * Form builder for testing submission of a form without a CSRF token.
 */
function form_test_validate_no_token($form, &$form_state) {
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  $form['#token'] = FALSE;
  return $form;
}

/**
 * Form submission handler for form_test_validate_no_token().
 */
function form_test_validate_no_token_submit($form, &$form_state) {
  drupal_set_message('The form_test_validate_no_token form has been submitted successfully.');
}

/**
 * Builds a simple form with a button triggering partial validation.
 */
function form_test_limit_validation_errors_form($form, &$form_state) {
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => 'Title',
    '#required' => TRUE,
  );
  $form['test'] = array(
    '#title' => 'Test',
    '#type' => 'textfield',
    '#element_validate' => array(
      'form_test_limit_validation_errors_element_validate_test',
    ),
  );
  $form['test_numeric_index'] = array(
    '#tree' => TRUE,
  );
  $form['test_numeric_index'][0] = array(
    '#title' => 'Test (numeric index)',
    '#type' => 'textfield',
    '#element_validate' => array(
      'form_test_limit_validation_errors_element_validate_test',
    ),
  );
  $form['test_substring'] = array(
    '#tree' => TRUE,
  );
  $form['test_substring']['foo'] = array(
    '#title' => 'Test (substring) foo',
    '#type' => 'textfield',
    '#element_validate' => array(
      'form_test_limit_validation_errors_element_validate_test',
    ),
  );
  $form['test_substring']['foobar'] = array(
    '#title' => 'Test (substring) foobar',
    '#type' => 'textfield',
    '#element_validate' => array(
      'form_test_limit_validation_errors_element_validate_test',
    ),
  );
  $form['actions']['partial'] = array(
    '#type' => 'submit',
    '#limit_validation_errors' => array(
      array(
        'test',
      ),
    ),
    '#submit' => array(
      'form_test_limit_validation_errors_form_partial_submit',
    ),
    '#value' => t('Partial validate'),
  );
  $form['actions']['partial_numeric_index'] = array(
    '#type' => 'submit',
    '#limit_validation_errors' => array(
      array(
        'test_numeric_index',
        0,
      ),
    ),
    '#submit' => array(
      'form_test_limit_validation_errors_form_partial_submit',
    ),
    '#value' => t('Partial validate (numeric index)'),
  );
  $form['actions']['substring'] = array(
    '#type' => 'submit',
    '#limit_validation_errors' => array(
      array(
        'test_substring',
        'foo',
      ),
    ),
    '#submit' => array(
      'form_test_limit_validation_errors_form_partial_submit',
    ),
    '#value' => t('Partial validate (substring)'),
  );
  $form['actions']['full'] = array(
    '#type' => 'submit',
    '#value' => t('Full validate'),
  );
  return $form;
}

/**
 * Form element validation handler for the 'test' element.
 */
function form_test_limit_validation_errors_element_validate_test(&$element, &$form_state) {
  if ($element['#value'] == 'invalid') {
    form_error($element, t('@label element is invalid', array(
      '@label' => $element['#title'],
    )));
  }
}

/**
 * Form submit handler for the partial validation submit button.
 */
function form_test_limit_validation_errors_form_partial_submit($form, $form_state) {

  // The title has not been validated, thus its value - in case of the test case
  // an empty string - may not be set.
  if (!isset($form_state['values']['title']) && isset($form_state['values']['test'])) {
    drupal_set_message('Only validated values appear in the form values.');
  }
}

/**
 * Create a header and options array. Helper function for callbacks.
 */
function _form_test_tableselect_get_data() {
  $header = array(
    'one' => t('One'),
    'two' => t('Two'),
    'three' => t('Three'),
    'four' => t('Four'),
  );
  $options['row1'] = array(
    'one' => 'row1col1',
    'two' => t('row1col2'),
    'three' => t('row1col3'),
    'four' => t('row1col4'),
  );
  $options['row2'] = array(
    'one' => 'row2col1',
    'two' => t('row2col2'),
    'three' => t('row2col3'),
    'four' => t('row2col4'),
  );
  $options['row3'] = array(
    'one' => 'row3col1',
    'two' => t('row3col2'),
    'three' => t('row3col3'),
    'four' => t('row3col4'),
  );
  return array(
    $header,
    $options,
  );
}

/**
 * Build a form to test the tableselect element.
 *
 * @param $form_state
 *   The form_state
 * @param $element_properties
 *   An array of element properties for the tableselect element.
 *
 * @return
 *   A form with a tableselect element and a submit button.
 */
function _form_test_tableselect_form_builder($form, $form_state, $element_properties) {
  list($header, $options) = _form_test_tableselect_get_data();
  $form['tableselect'] = $element_properties;
  $form['tableselect'] += array(
    '#prefix' => '<div id="tableselect-wrapper">',
    '#suffix' => '</div>',
    '#type' => 'tableselect',
    '#header' => $header,
    '#options' => $options,
    '#multiple' => FALSE,
    '#empty' => t('Empty text.'),
    '#ajax' => array(
      'callback' => '_form_test_tableselect_ajax_callback',
      'wrapper' => 'tableselect-wrapper',
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Test the tableselect #multiple = TRUE functionality.
 */
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.
 */
function _form_test_tableselect_multiple_false_form($form, $form_state) {
  return _form_test_tableselect_form_builder($form, $form_state, array(
    '#multiple' => FALSE,
  ));
}

/**
 * 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.
 */
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.
 */
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.
 */
function _form_test_vertical_tabs_form($form, &$form_state) {
  $form['vertical_tabs'] = array(
    '#type' => 'vertical_tabs',
  );
  $form['tab1'] = array(
    '#type' => 'fieldset',
    '#title' => t('Tab 1'),
    '#collapsible' => TRUE,
    '#group' => 'vertical_tabs',
  );
  $form['tab1']['field1'] = array(
    '#title' => t('Field 1'),
    '#type' => 'textfield',
  );
  $form['tab2'] = array(
    '#type' => 'fieldset',
    '#title' => t('Tab 2'),
    '#collapsible' => TRUE,
    '#group' => 'vertical_tabs',
  );
  $form['tab2']['field2'] = array(
    '#title' => t('Field 2'),
    '#type' => 'textfield',
  );
  return $form;
}

/**
* Ajax callback that returns the form element.
*/
function _form_test_tableselect_ajax_callback($form, &$form_state) {
  return $form['tableselect'];
}

/**
 * A multistep form for testing the form storage.
 *
 * It uses two steps for editing a virtual "thing". Any changes to it are saved
 * in the form storage and have to be present during any step. By setting the
 * request parameter "cache" the form can be tested with caching enabled, as
 * it would be the case, if the form would contain some #ajax callbacks.
 *
 * @see form_test_storage_form_submit()
 */
function form_test_storage_form($form, &$form_state) {
  if ($form_state['rebuild']) {
    $form_state['input'] = array();
  }

  // Initialize
  if (empty($form_state['storage'])) {
    if (empty($form_state['input'])) {
      $_SESSION['constructions'] = 0;
    }

    // Put the initial thing into the storage
    $form_state['storage'] = array(
      'thing' => array(
        'title' => 'none',
        'value' => '',
      ),
    );
  }

  // Count how often the form is constructed.
  $_SESSION['constructions']++;
  drupal_set_message("Form constructions: " . $_SESSION['constructions']);
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => 'Title',
    '#default_value' => $form_state['storage']['thing']['title'],
    '#required' => TRUE,
  );
  $form['value'] = array(
    '#type' => 'textfield',
    '#title' => 'Value',
    '#default_value' => $form_state['storage']['thing']['value'],
    '#element_validate' => array(
      'form_test_storage_element_validate_value_cached',
    ),
  );
  $form['continue_button'] = array(
    '#type' => 'button',
    '#value' => 'Reset',
  );
  $form['continue_submit'] = array(
    '#type' => 'submit',
    '#value' => 'Continue submit',
    '#submit' => array(
      'form_storage_test_form_continue_submit',
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  if (isset($_REQUEST['cache'])) {

    // Manually activate caching, so we can test that the storage keeps working
    // when it's enabled.
    $form_state['cache'] = TRUE;
  }
  if (isset($_REQUEST['immutable'])) {
    $form_state['build_info']['immutable'] = TRUE;
  }
  return $form;
}

/**
 * Emulate legacy AHAH-style ajax callback.
 *
 * Drupal 6 AHAH callbacks used to operate directly on forms retrieved using
 * form_get_cache and stored using form_set_cache after manipulation. This
 * callback helps testing whether form_set_cache prevents resaving of immutable
 * forms.
 */
function form_test_storage_legacy_handler($form_build_id) {
  $form_state = array();
  $form = form_get_cache($form_build_id, $form_state);
  drupal_json_output(array(
    'form' => $form,
    'form_state' => $form_state,
  ));
  $form['#poisoned'] = TRUE;
  $form_state['poisoned'] = TRUE;
  form_set_cache($form_build_id, $form, $form_state);
}

/**
 * Form element validation handler for 'value' element in form_test_storage_form().
 *
 * Tests updating of cached form storage during validation.
 */
function form_test_storage_element_validate_value_cached($element, &$form_state) {

  // If caching is enabled and we receive a certain value, change the storage.
  // This presumes that another submitted form value triggers a validation error
  // elsewhere in the form. Form API should still update the cached form storage
  // though.
  if (isset($_REQUEST['cache']) && $form_state['values']['value'] == 'change_title') {
    $form_state['storage']['thing']['changed'] = TRUE;
  }
}

/**
 * Form submit handler to continue multi-step form.
 */
function form_storage_test_form_continue_submit($form, &$form_state) {
  $form_state['storage']['thing']['title'] = $form_state['values']['title'];
  $form_state['storage']['thing']['value'] = $form_state['values']['value'];
  $form_state['rebuild'] = TRUE;
}

/**
 * Form submit handler to finish multi-step form.
 */
function form_test_storage_form_submit($form, &$form_state) {
  drupal_set_message("Title: " . check_plain($form_state['values']['title']));
  drupal_set_message("Form constructions: " . $_SESSION['constructions']);
  if (isset($form_state['storage']['thing']['changed'])) {
    drupal_set_message("The thing has been changed.");
  }
  $form_state['redirect'] = 'node';
}

/**
 * A simple form for testing form storage when page caching is enabled.
 */
function form_test_storage_page_cache_form($form, &$form_state) {
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => 'Title',
    '#required' => TRUE,
  );
  $form['test_build_id_old'] = array(
    '#type' => 'item',
    '#title' => 'Old build id',
    '#markup' => 'No old build id',
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  $form['rebuild'] = array(
    '#type' => 'submit',
    '#value' => 'Rebuild',
    '#submit' => array(
      'form_test_storage_page_cache_rebuild',
    ),
  );
  $form['#after_build'] = array(
    'form_test_storage_page_cache_old_build_id',
  );
  $form_state['cache'] = TRUE;
  return $form;
}

/**
 * Form element #after_build callback: output the old form build-id.
 */
function form_test_storage_page_cache_old_build_id($form) {
  if (isset($form['#build_id_old'])) {
    $form['test_build_id_old']['#markup'] = check_plain($form['#build_id_old']);
  }
  return $form;
}

/**
 * Form submit callback: Rebuild the form and continue.
 */
function form_test_storage_page_cache_rebuild($form, &$form_state) {
  $form_state['rebuild'] = TRUE;
}

/**
 * A simple form for testing form caching.
 */
function form_test_cache_form($form, &$form_state) {
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => 'Title',
    '#required' => TRUE,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  return $form;
}

/**
 * A form for testing form labels and required marks.
 */
function form_label_test_form() {
  $form['form_checkboxes_test'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Checkboxes test'),
    '#options' => array(
      'first-checkbox' => t('First checkbox'),
      'second-checkbox' => t('Second checkbox'),
      'third-checkbox' => t('Third checkbox'),
      '0' => t('0'),
    ),
  );
  $form['form_radios_test'] = array(
    '#type' => 'radios',
    '#title' => t('Radios test'),
    '#options' => array(
      'first-radio' => t('First radio'),
      'second-radio' => t('Second radio'),
      'third-radio' => t('Third radio'),
      '0' => t('0'),
    ),
    // Test #field_prefix and #field_suffix placement.
    '#field_prefix' => '<span id="form-test-radios-field-prefix">' . t('Radios #field_prefix element') . '</span>',
    '#field_suffix' => '<span id="form-test-radios-field-suffix">' . t('Radios #field_suffix element') . '</span>',
  );
  $form['form_checkbox_test'] = array(
    '#type' => 'checkbox',
    '#title' => t('Checkbox test'),
  );
  $form['form_textfield_test_title_and_required'] = array(
    '#type' => 'textfield',
    '#title' => t('Textfield test for required with title'),
    '#required' => TRUE,
  );
  $form['form_textfield_test_no_title_required'] = array(
    '#type' => 'textfield',
    // We use an empty title, since not setting #title suppresses the label
    // and required marker.
    '#title' => '',
    '#required' => TRUE,
  );
  $form['form_textfield_test_title'] = array(
    '#type' => 'textfield',
    '#title' => t('Textfield test for title only'),
    // Not required.
    // Test #prefix and #suffix placement.
    '#prefix' => '<div id="form-test-textfield-title-prefix">' . t('Textfield #prefix element') . '</div>',
    '#suffix' => '<div id="form-test-textfield-title-suffix">' . t('Textfield #suffix element') . '</div>',
  );
  $form['form_textfield_test_title_after'] = array(
    '#type' => 'textfield',
    '#title' => t('Textfield test for title after element'),
    '#title_display' => 'after',
  );
  $form['form_textfield_test_title_invisible'] = array(
    '#type' => 'textfield',
    '#title' => t('Textfield test for invisible title'),
    '#title_display' => 'invisible',
  );

  // Textfield test for title set not to display.
  $form['form_textfield_test_title_no_show'] = array(
    '#type' => 'textfield',
  );

  // Checkboxes & radios with title as attribute.
  $form['form_checkboxes_title_attribute'] = array(
    '#type' => 'checkboxes',
    '#title' => 'Checkboxes test',
    '#options' => array(
      'first-checkbox' => 'First checkbox',
      'second-checkbox' => 'Second checkbox',
    ),
    '#title_display' => 'attribute',
    '#required' => TRUE,
  );
  $form['form_radios_title_attribute'] = array(
    '#type' => 'radios',
    '#title' => 'Radios test',
    '#options' => array(
      'first-radio' => 'First radio',
      'second-radio' => 'Second radio',
    ),
    '#title_display' => 'attribute',
    '#required' => TRUE,
  );
  return $form;
}

/**
 * Menu callback; Invokes a form builder function with a wrapper callback.
 */
function form_test_wrapper_callback($form_id) {
  $form_state = array(
    'build_info' => array(
      'args' => array(),
    ),
    'wrapper_callback' => 'form_test_wrapper_callback_wrapper',
  );
  return drupal_build_form($form_id, $form_state);
}

/**
 * Form wrapper for form_test_wrapper_callback_form().
 */
function form_test_wrapper_callback_wrapper($form, &$form_state) {
  $form['wrapper'] = array(
    '#markup' => 'Form wrapper callback element output.',
  );
  return $form;
}

/**
 * Form builder for form wrapper callback test.
 */
function form_test_wrapper_callback_form($form, &$form_state) {
  $form['builder'] = array(
    '#markup' => 'Form builder element output.',
  );
  return $form;
}

/**
 * Form builder for form_state_values_clean() test.
 */
function form_test_form_state_values_clean_form($form, &$form_state) {

  // Build an example form containing multiple submit and button elements; not
  // only on the top-level.
  $form = array(
    '#tree' => TRUE,
  );
  $form['foo'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  $form['bar'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  $form['beer'] = array(
    '#type' => 'value',
    '#value' => 1000,
  );
  $form['baz']['foo'] = array(
    '#type' => 'button',
    '#value' => t('Submit'),
  );
  $form['baz']['baz'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  $form['baz']['beer'] = array(
    '#type' => 'value',
    '#value' => 2000,
  );
  return $form;
}

/**
 * Form submit handler for form_state_values_clean() test form.
 */
function form_test_form_state_values_clean_form_submit($form, &$form_state) {
  form_state_values_clean($form_state);
  drupal_json_output($form_state['values']);
  exit;
}

/**
 * Form constructor for the form_state_values_clean() test.
 */
function form_test_form_state_values_clean_advanced_form($form, &$form_state) {

  // Build an example form containing a managed file and a submit form element.
  $form['image'] = array(
    '#type' => 'managed_file',
    '#title' => t('Image'),
    '#upload_location' => 'public://',
    '#default_value' => 0,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Form submission handler for form_test_form_state_values_clean_advanced_form().
 */
function form_test_form_state_values_clean_advanced_form_submit($form, &$form_state) {
  form_state_values_clean($form_state);
  print t('You WIN!');
  exit;
}

/**
 * Build a form to test a checkbox.
 */
function _form_test_checkbox($form, &$form_state) {

  // 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;
}

/**
 * Return the form values via JSON.
 */
function _form_test_checkbox_submit($form, &$form_state) {
  drupal_json_output($form_state['values']);
  exit;
}

/**
 * Builds a form to test #type 'select' validation.
 */
function form_test_select($form, &$form_state) {
  $base = array(
    '#type' => 'select',
    '#options' => drupal_map_assoc(array(
      'one',
      'two',
      'three',
    )),
  );
  $form['select'] = $base + array(
    '#title' => '#default_value one',
    '#default_value' => 'one',
  );
  $form['select_required'] = $base + array(
    '#title' => '#default_value one, #required',
    '#required' => TRUE,
    '#default_value' => 'one',
  );
  $form['select_optional'] = $base + array(
    '#title' => '#default_value one, not #required',
    '#required' => FALSE,
    '#default_value' => 'one',
  );
  $form['empty_value'] = $base + array(
    '#title' => '#default_value one, #required, #empty_value 0',
    '#required' => TRUE,
    '#default_value' => 'one',
    '#empty_value' => 0,
  );
  $form['empty_value_one'] = $base + array(
    '#title' => '#default_value = #empty_value, #required',
    '#required' => TRUE,
    '#default_value' => 'one',
    '#empty_value' => 'one',
  );
  $form['no_default'] = $base + array(
    '#title' => 'No #default_value, #required',
    '#required' => TRUE,
  );
  $form['no_default_optional'] = $base + array(
    '#title' => 'No #default_value, not #required',
    '#required' => FALSE,
    '#description' => 'Should result in "one", because it is not required and there is no #empty_value requested, so default browser behavior of preselecting first option is in effect.',
  );
  $form['no_default_optional_empty_value'] = $base + array(
    '#title' => 'No #default_value, not #required, #empty_value empty string',
    '#empty_value' => '',
    '#required' => FALSE,
    '#description' => 'Should result in an empty string (due to #empty_value), because it is optional.',
  );
  $form['no_default_empty_option'] = $base + array(
    '#title' => 'No #default_value, #required, #empty_option',
    '#required' => TRUE,
    '#empty_option' => '- Choose -',
  );
  $form['no_default_empty_option_optional'] = $base + array(
    '#title' => 'No #default_value, not #required, #empty_option',
    '#empty_option' => '- Dismiss -',
    '#description' => 'Should result in an empty string (default of #empty_value), because it is optional.',
  );
  $form['no_default_empty_value'] = $base + array(
    '#title' => 'No #default_value, #required, #empty_value 0',
    '#required' => TRUE,
    '#empty_value' => 0,
    '#description' => 'Should never result in 0.',
  );
  $form['no_default_empty_value_one'] = $base + array(
    '#title' => 'No #default_value, #required, #empty_value one',
    '#required' => TRUE,
    '#empty_value' => 'one',
    '#description' => 'A mistakenly assigned #empty_value contained in #options should not be valid.',
  );
  $form['no_default_empty_value_optional'] = $base + array(
    '#title' => 'No #default_value, not #required, #empty_value 0',
    '#required' => FALSE,
    '#empty_value' => 0,
    '#description' => 'Should result in 0, because it is optional.',
  );
  $form['multiple'] = $base + array(
    '#title' => '#multiple, #default_value two',
    '#default_value' => array(
      'two',
    ),
    '#multiple' => TRUE,
  );
  $form['multiple_no_default'] = $base + array(
    '#title' => '#multiple, no #default_value',
    '#multiple' => TRUE,
  );
  $form['multiple_no_default_required'] = $base + array(
    '#title' => '#multiple, #required, no #default_value',
    '#required' => TRUE,
    '#multiple' => TRUE,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  return $form;
}

/**
 * Form submit handler for form_test_select().
 */
function form_test_select_submit($form, &$form_state) {
  drupal_json_output($form_state['values']);
  exit;
}

/**
 * Form constructor to test expansion of #type checkboxes and radios.
 */
function form_test_checkboxes_radios($form, &$form_state, $customize = FALSE) {
  $form['#submit'] = array(
    '_form_test_submit_values_json',
  );

  // Expand #type checkboxes, setting custom element properties for some but not
  // all options.
  $form['checkboxes'] = array(
    '#type' => 'checkboxes',
    '#title' => 'Checkboxes',
    '#options' => array(
      0 => 'Zero',
      'foo' => 'Foo',
      1 => 'One',
      'bar' => 'Bar',
      '>' => 'Special Char',
    ),
  );
  if ($customize) {
    $form['checkboxes'] += array(
      'foo' => array(
        '#description' => 'Enable to foo.',
      ),
      1 => array(
        '#weight' => 10,
      ),
    );
  }

  // Expand #type radios, setting custom element properties for some but not
  // all options.
  $form['radios'] = array(
    '#type' => 'radios',
    '#title' => 'Radios',
    '#options' => array(
      0 => 'Zero',
      'foo' => 'Foo',
      1 => 'One',
      'bar' => 'Bar',
      '>' => 'Special Char',
    ),
  );
  if ($customize) {
    $form['radios'] += array(
      'foo' => array(
        '#description' => 'Enable to foo.',
      ),
      1 => array(
        '#weight' => 10,
      ),
    );
  }
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  return $form;
}

/**
 * Build a form to test disabled elements.
 */
function _form_test_disabled_elements($form, &$form_state) {

  // Elements that take a simple default value.
  foreach (array(
    'textfield',
    'textarea',
    'hidden',
  ) as $type) {
    $form[$type] = array(
      '#type' => $type,
      '#title' => $type,
      '#default_value' => $type,
      '#test_hijack_value' => 'HIJACK',
      '#disabled' => TRUE,
    );
  }

  // Multiple values option elements.
  foreach (array(
    'checkboxes',
    'select',
  ) as $type) {
    $form[$type . '_multiple'] = array(
      '#type' => $type,
      '#title' => $type . ' (multiple)',
      '#options' => array(
        'test_1' => 'Test 1',
        'test_2' => 'Test 2',
      ),
      '#multiple' => TRUE,
      '#default_value' => array(
        'test_2' => 'test_2',
      ),
      // The keys of #test_hijack_value need to match the #name of the control.
      // @see FormsTestCase::testDisabledElements()
      '#test_hijack_value' => $type == 'select' ? array(
        '' => 'test_1',
      ) : array(
        'test_1' => 'test_1',
      ),
      '#disabled' => TRUE,
    );
  }

  // Single values option elements.
  foreach (array(
    'radios',
    'select',
  ) as $type) {
    $form[$type . '_single'] = array(
      '#type' => $type,
      '#title' => $type . ' (single)',
      '#options' => array(
        'test_1' => 'Test 1',
        'test_2' => 'Test 2',
      ),
      '#multiple' => FALSE,
      '#default_value' => 'test_2',
      '#test_hijack_value' => 'test_1',
      '#disabled' => TRUE,
    );
  }

  // Checkbox and radio.
  foreach (array(
    'checkbox',
    'radio',
  ) as $type) {
    $form[$type . '_unchecked'] = array(
      '#type' => $type,
      '#title' => $type . ' (unchecked)',
      '#return_value' => 1,
      '#default_value' => 0,
      '#test_hijack_value' => 1,
      '#disabled' => TRUE,
    );
    $form[$type . '_checked'] = array(
      '#type' => $type,
      '#title' => $type . ' (checked)',
      '#return_value' => 1,
      '#default_value' => 1,
      '#test_hijack_value' => NULL,
      '#disabled' => TRUE,
    );
  }

  // Weight.
  $form['weight'] = array(
    '#type' => 'weight',
    '#title' => 'weight',
    '#default_value' => 10,
    '#test_hijack_value' => 5,
    '#disabled' => TRUE,
  );

  // Date.
  $form['date'] = array(
    '#type' => 'date',
    '#title' => 'date',
    '#disabled' => TRUE,
    '#default_value' => array(
      'day' => 19,
      'month' => 11,
      'year' => 1978,
    ),
    '#test_hijack_value' => array(
      'day' => 20,
      'month' => 12,
      'year' => 1979,
    ),
  );

  // The #disabled state should propagate to children.
  $form['disabled_container'] = array(
    '#disabled' => TRUE,
  );
  foreach (array(
    'textfield',
    'textarea',
    'hidden',
  ) as $type) {
    $form['disabled_container']['disabled_container_' . $type] = array(
      '#type' => $type,
      '#title' => $type,
      '#default_value' => $type,
      '#test_hijack_value' => 'HIJACK',
    );
  }

  // Text format.
  $form['text_format'] = array(
    '#type' => 'text_format',
    '#title' => 'Text format',
    '#disabled' => TRUE,
    '#default_value' => 'Text value',
    '#format' => 'plain_text',
    '#expected_value' => array(
      'value' => 'Text value',
      'format' => 'plain_text',
    ),
    '#test_hijack_value' => array(
      'value' => 'HIJACK',
      'format' => 'filtered_html',
    ),
  );

  // Password fields.
  $form['password'] = array(
    '#type' => 'password',
    '#title' => 'Password',
    '#disabled' => TRUE,
  );
  $form['password_confirm'] = array(
    '#type' => 'password_confirm',
    '#title' => 'Password confirm',
    '#disabled' => TRUE,
  );

  // Files.
  $form['file'] = array(
    '#type' => 'file',
    '#title' => 'File',
    '#disabled' => TRUE,
  );
  $form['managed_file'] = array(
    '#type' => 'managed_file',
    '#title' => 'Managed file',
    '#disabled' => TRUE,
  );

  // Buttons.
  $form['image_button'] = array(
    '#type' => 'image_button',
    '#value' => 'Image button',
    '#disabled' => TRUE,
  );
  $form['button'] = array(
    '#type' => 'button',
    '#value' => 'Button',
    '#disabled' => TRUE,
  );
  $form['submit_disabled'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
    '#disabled' => TRUE,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Return the form values via JSON.
 */
function _form_test_disabled_elements_submit($form, &$form_state) {
  drupal_json_output($form_state['values']);
  exit;
}

/**
 * Build a form to test input forgery of enabled elements.
 */
function _form_test_input_forgery($form, &$form_state) {

  // For testing that a user can't submit a value not matching one of the
  // allowed options.
  $form['checkboxes'] = array(
    '#type' => 'checkboxes',
    '#options' => array(
      'one' => 'One',
      'two' => 'Two',
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Return the form values via JSON.
 */
function _form_test_input_forgery_submit($form, &$form_state) {
  drupal_json_output($form_state['values']);
  exit;
}

/**
 * Form builder for testing preservation of values during a rebuild.
 */
function form_test_form_rebuild_preserve_values_form($form, &$form_state) {

  // Start the form with two checkboxes, to test different defaults, and a
  // textfield, to test more than one element type.
  $form = array(
    'checkbox_1_default_off' => array(
      '#type' => 'checkbox',
      '#title' => t('This checkbox defaults to unchecked.'),
      '#default_value' => FALSE,
    ),
    'checkbox_1_default_on' => array(
      '#type' => 'checkbox',
      '#title' => t('This checkbox defaults to checked.'),
      '#default_value' => TRUE,
    ),
    'text_1' => array(
      '#type' => 'textfield',
      '#title' => t('This textfield has a non-empty default value.'),
      '#default_value' => 'DEFAULT 1',
    ),
  );

  // Provide an 'add more' button that rebuilds the form with an additional two
  // checkboxes and a textfield. The test is to make sure that the rebuild
  // triggered by this button preserves the user input values for the initial
  // elements and initializes the new elements with the correct default values.
  if (empty($form_state['storage']['add_more'])) {
    $form['add_more'] = array(
      '#type' => 'submit',
      '#value' => 'Add more',
      '#submit' => array(
        'form_test_form_rebuild_preserve_values_form_add_more',
      ),
    );
  }
  else {
    $form += array(
      'checkbox_2_default_off' => array(
        '#type' => 'checkbox',
        '#title' => t('This checkbox defaults to unchecked.'),
        '#default_value' => FALSE,
      ),
      'checkbox_2_default_on' => array(
        '#type' => 'checkbox',
        '#title' => t('This checkbox defaults to checked.'),
        '#default_value' => TRUE,
      ),
      'text_2' => array(
        '#type' => 'textfield',
        '#title' => t('This textfield has a non-empty default value.'),
        '#default_value' => 'DEFAULT 2',
      ),
    );
  }

  // A submit button that finishes the form workflow (does not rebuild).
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  return $form;
}

/**
 * Button submit handler for form_test_form_rebuild_preserve_values_form().
 */
function form_test_form_rebuild_preserve_values_form_add_more($form, &$form_state) {

  // Rebuild, to test preservation of input values.
  $form_state['storage']['add_more'] = TRUE;
  $form_state['rebuild'] = TRUE;
}

/**
 * Form submit handler for form_test_form_rebuild_preserve_values_form().
 */
function form_test_form_rebuild_preserve_values_form_submit($form, &$form_state) {

  // Finish the workflow. Do not rebuild.
  drupal_set_message(t('Form values: %values', array(
    '%values' => var_export($form_state['values'], TRUE),
  )));
}

/**
 * Form constructor for testing form state persistence.
 */
function form_test_state_persist($form, &$form_state) {
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => 'title',
    '#default_value' => 'DEFAULT',
    '#required' => TRUE,
  );
  $form_state['value'] = 'State persisted.';
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Submit handler.
 *
 * @see form_test_state_persist()
 */
function form_test_state_persist_submit($form, &$form_state) {
  drupal_set_message($form_state['value']);
  $form_state['rebuild'] = TRUE;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * @see form_test_state_persist()
 */
function form_test_form_form_test_state_persist_alter(&$form, &$form_state) {

  // Simulate a form alter implementation inserting form elements that enable
  // caching of the form, e.g. elements having #ajax.
  if (!empty($_REQUEST['cache'])) {
    $form_state['cache'] = TRUE;
  }
}

/**
 * Form builder to test programmatic form submissions.
 */
function form_test_programmatic_form($form, &$form_state) {
  $form['textfield'] = array(
    '#title' => 'Textfield',
    '#type' => 'textfield',
  );
  $form['checkboxes'] = array(
    '#type' => 'checkboxes',
    '#options' => array(
      1 => 'First checkbox',
      2 => 'Second checkbox',
    ),
    // Both checkboxes are selected by default so that we can test the ability
    // of programmatic form submissions to uncheck them.
    '#default_value' => array(
      1,
      2,
    ),
  );

  // This is used to test that programmatic form submissions can bypass #access
  // restrictions.
  $form['textfield_no_access'] = array(
    '#type' => 'textfield',
    '#title' => 'Textfield no access',
    '#default_value' => 'default value',
    '#access' => FALSE,
  );
  $form['field_to_validate'] = array(
    '#type' => 'radios',
    '#title' => 'Field to validate (in the case of limited validation)',
    '#description' => 'If the form is submitted by clicking the "Submit with limited validation" button, then validation can be limited based on the value of this radio button.',
    '#options' => array(
      'all' => 'Validate all fields',
      'textfield' => 'Validate the "Textfield" field',
      'field_to_validate' => 'Validate the "Field to validate" field',
    ),
    '#default_value' => 'all',
  );

  // The main submit button for the form.
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );

  // A secondary submit button that allows validation to be limited based on
  // the value of the above radio selector.
  $form['submit_limit_validation'] = array(
    '#type' => 'submit',
    '#value' => 'Submit with limited validation',
    // Use the same submit handler for this button as for the form itself.
    // (This must be set explicitly or otherwise the form API will ignore the
    // #limit_validation_errors property.)
    '#submit' => array(
      'form_test_programmatic_form_submit',
    ),
  );
  if (!empty($form_state['input']['field_to_validate']) && $form_state['input']['field_to_validate'] != 'all') {
    $form['submit_limit_validation']['#limit_validation_errors'] = array(
      array(
        $form_state['input']['field_to_validate'],
      ),
    );
  }
  return $form;
}

/**
 * Form validation handler for programmatic form submissions.
 *
 * To test that the validation handler is correctly executed, the field value is
 * explicitly required here.
 */
function form_test_programmatic_form_validate($form, &$form_state) {
  if (empty($form_state['values']['textfield'])) {
    form_set_error('textfield', t('Textfield is required.'));
  }
}

/**
 * Form submit handler for programmatic form submissions.
 *
 * To test that the submission handler is correctly executed, we store the
 * submitted values in a place we can access from the caller context.
 */
function form_test_programmatic_form_submit($form, &$form_state) {
  $form_state['storage']['programmatic_form_submit'] = $form_state['values'];
}

/**
 * Form builder to test button click detection.
 */
function form_test_clicked_button($form, &$form_state) {

  // A single text field. In IE, when a form has only one non-button input field
  // and the ENTER key is pressed while that field has focus, the form is
  // submitted without any information identifying the button responsible for
  // the submission. In other browsers, the form is submitted as though the
  // first button were clicked.
  $form['text'] = array(
    '#title' => 'Text',
    '#type' => 'textfield',
  );

  // Loop through each path argument, addding buttons based on the information
  // in the argument. For example, if the path is
  // form-test/clicked-button/s/i/rb, then 3 buttons are added: a 'submit', an
  // 'image_button', and a 'button' with #access=FALSE. This enables form.test
  // to test a variety of combinations.
  $i = 0;
  $args = array_slice(arg(), 2);
  foreach ($args as $arg) {
    $name = 'button' . ++$i;

    // 's', 'b', or 'i' in the argument define the button type wanted.
    if (strpos($arg, 's') !== FALSE) {
      $type = 'submit';
    }
    elseif (strpos($arg, 'b') !== FALSE) {
      $type = 'button';
    }
    elseif (strpos($arg, 'i') !== FALSE) {
      $type = 'image_button';
    }
    else {
      $type = NULL;
    }
    if (isset($type)) {
      $form[$name] = array(
        '#type' => $type,
        '#name' => $name,
      );

      // Image buttons need a #src; the others need a #value.
      if ($type == 'image_button') {
        $form[$name]['#src'] = 'misc/druplicon.png';
      }
      else {
        $form[$name]['#value'] = $name;
      }

      // 'r' for restricted, so we can test that button click detection code
      // correctly takes #access security into account.
      if (strpos($arg, 'r') !== FALSE) {
        $form[$name]['#access'] = FALSE;
      }
    }
  }
  return $form;
}

/**
 * Form validation handler for the form_test_clicked_button() form.
 */
function form_test_clicked_button_validate($form, &$form_state) {
  if (isset($form_state['triggering_element'])) {
    drupal_set_message(t('The clicked button is %name.', array(
      '%name' => $form_state['triggering_element']['#name'],
    )));
  }
  else {
    drupal_set_message('There is no clicked button.');
  }
}

/**
 * Form submit handler for the form_test_clicked_button() form.
 */
function form_test_clicked_button_submit($form, &$form_state) {
  drupal_set_message('Submit handler for form_test_clicked_button executed.');
}

/**
 * Form builder to detect form redirect.
 */
function form_test_redirect($form, &$form_state) {
  $form['redirection'] = array(
    '#type' => 'checkbox',
    '#title' => t('Use redirection'),
  );
  $form['destination'] = array(
    '#type' => 'textfield',
    '#title' => t('Redirect destination'),
    '#states' => array(
      'visible' => array(
        ':input[name="redirection"]' => array(
          'checked' => TRUE,
        ),
      ),
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

/**
 * Form submit handler to test different redirect behaviours.
 */
function form_test_redirect_submit(&$form, &$form_state) {
  if (!empty($form_state['values']['redirection'])) {
    $form_state['redirect'] = !empty($form_state['values']['destination']) ? $form_state['values']['destination'] : NULL;
  }
  else {
    $form_state['redirect'] = FALSE;
  }
}

/**
 * Implements hook_form_FORM_ID_alter() for the registration form.
 */
function form_test_form_user_register_form_alter(&$form, &$form_state) {
  $form['test_rebuild'] = array(
    '#type' => 'submit',
    '#value' => t('Rebuild'),
    '#submit' => array(
      'form_test_user_register_form_rebuild',
    ),
  );

  // If requested, add the test field by attaching the node page form.
  if (!empty($_REQUEST['field'])) {
    $node = (object) array(
      'type' => 'page',
    );
    field_attach_form('node', $node, $form, $form_state);
  }
}

/**
 * Submit callback that just lets the form rebuild.
 */
function form_test_user_register_form_rebuild($form, &$form_state) {
  drupal_set_message('Form rebuilt.');
  $form_state['rebuild'] = TRUE;
}

/**
 * Menu callback that returns two instances of the node form.
 */
function form_test_two_instances() {
  global $user;
  $node1 = (object) array(
    'uid' => $user->uid,
    'name' => isset($user->name) ? $user->name : '',
    'type' => 'page',
    'language' => LANGUAGE_NONE,
  );
  $node2 = clone $node1;
  $return['node_form_1'] = drupal_get_form('page_node_form', $node1);
  $return['node_form_2'] = drupal_get_form('page_node_form', $node2);
  return $return;
}

/**
 * Menu callback for testing custom form includes.
 */
function form_test_load_include_custom($form, &$form_state) {
  $form['button'] = array(
    '#type' => 'submit',
    '#value' => t('Save'),
    '#submit' => array(
      'form_test_load_include_submit',
    ),
  );

  // Specify the include file and enable form caching. That way the form is
  // cached when it is submitted, but needs to find the specified submit handler
  // in the include.
  // Filename is a bit weird here: modules/simpletest/tests/form_test.file.inc
  form_load_include($form_state, 'inc', 'form_test', 'form_test.file');
  $form_state['cache'] = TRUE;
  return $form;
}
function form_test_checkbox_type_juggling($form, $form_state, $default_value, $return_value) {
  $form['checkbox'] = array(
    '#type' => 'checkbox',
    '#return_value' => $return_value,
    '#default_value' => $default_value,
  );
  return $form;
}
function form_test_checkboxes_zero($form, &$form_state, $json = TRUE) {
  $form['checkbox_off'] = array(
    '#type' => 'checkboxes',
    '#options' => array(
      'foo',
      'bar',
      'baz',
    ),
  );
  $form['checkbox_zero_default'] = array(
    '#type' => 'checkboxes',
    '#options' => array(
      'foo',
      'bar',
      'baz',
    ),
    '#default_value' => array(
      0,
    ),
  );
  $form['checkbox_string_zero_default'] = array(
    '#type' => 'checkboxes',
    '#options' => array(
      'foo',
      'bar',
      'baz',
    ),
    '#default_value' => array(
      '0',
    ),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  if ($json) {
    $form['#submit'][] = '_form_test_checkbox_submit';
  }
  else {
    $form['#submit'][] = '_form_test_checkboxes_zero_no_redirect';
  }
  return $form;
}
function _form_test_checkboxes_zero_no_redirect($form, &$form_state) {
  $form_state['redirect'] = FALSE;
}

/**
 * Menu callback returns two instances of the same form.
 */
function form_test_double_form() {
  return array(
    'form1' => drupal_get_form('form_test_html_id'),
    'form2' => drupal_get_form('form_test_html_id'),
  );
}

/**
 * Builds a simple form to test duplicate HTML IDs.
 */
function form_test_html_id($form, &$form_state) {
  $form['name'] = array(
    '#type' => 'textfield',
    '#title' => 'name',
    '#required' => TRUE,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save',
  );
  return $form;
}