drupal_web_test_case.php

<?php
// $Id$

/**
 * Test case for typical Drupal tests.
 */
class DrupalWebTestCase {

  /**
   * The test run ID.
   *
   * @var string
   */
  protected $testId;

  /**
   * The URL currently loaded in the internal browser.
   *
   * @var string
   */
  protected $url;

  /**
   * The handle of the current cURL connection.
   *
   * @var resource
   */
  protected $curlHandle;

  /**
   * The content of the page currently loaded in the internal browser.
   *
   * @var string
   */
  protected $content;

  /**
   * The content of the page currently loaded in the internal browser (plain text version).
   *
   * @var string
   */
  protected $plainTextContent;

  /**
   * The parsed version of the page.
   *
   * @var SimpleXMLElement
   */
  protected $elements = NULL;

  /**
   * Whether a user is logged in the internal browser.
   *
   * @var bool
   */
  protected $isLoggedIn = FALSE;

  /**
   * The current cookie file used by cURL.
   *
   * We do not reuse the cookies in further runs, so we do not need a file
   * but we still need cookie handling, so we set the jar to NULL.
   */
  protected $cookieFile = NULL;

  /**
   * Additional cURL options.
   *
   * DrupalWebTestCase itself never sets this but always obeys what is set.
   */
  protected $additionalCurlOptions = array();

  /**
   * The original database prefix, before it was changed for testing purposes.
   *
   * @var string
   */
  protected $originalPrefix = NULL;

  /**
   * The original file directory, before it was changed for testing purposes.
   *
   * @var string
   */
  protected $originalFileDirectory = NULL;

  /**
   * Current results of this test case.
   *
   * @var Array
   */
  public $results = array(
    '#pass' => 0,
    '#fail' => 0,
    '#exception' => 0,
  );

  /**
   * Assertions thrown in that test case.
   *
   * @var Array
   */
  protected $assertions = array();

  /**
   * Constructor for DrupalWebTestCase.
   *
   * @param $test_id
   *   Tests with the same id are reported together.
   */
  public function __construct($test_id = NULL) {
    $this->testId = $test_id;
  }

  /**
   * Internal helper: stores the assert.
   *
   * @param $status
   *   Can be 'pass', 'fail', 'exception'.
   *   TRUE is a synonym for 'pass', FALSE for 'fail'.
   * @param $message
   *   The message string.
   * @param $group
   *   WHich group this assert belongs to.
   * @param $caller
   *   By default, the assert comes from a function which names start with
   *   'test'. Instead, you can specify where this assert originates from
   *   by passing in an associative array as $caller. Key 'file' is
   *   the name of the source file, 'line' is the line number and 'function'
   *   is the caller function itself.
   */
  private function assert($status, $message = '', $group = 'Other', $caller = NULL) {
    global $db_prefix;

    // Convert boolean status to string status.
    if (is_bool($status)) {
      $status = $status ? 'pass' : 'fail';
    }

    // Increment summary result counter.
    $this->results['#' . $status]++;

    // Get the function information about the call to the assertion method.
    if (!$caller) {
      $caller = $this->getAssertionCall();
    }

    // Switch to non-testing database to store results in.
    $current_db_prefix = $db_prefix;
    $db_prefix = $this->originalPrefix;

    // Creation assertion array that can be displayed while tests are running.
    $this->assertions[] = $assertion = array(
      'test_id' => $this->testId,
      'test_class' => get_class($this),
      'status' => $status,
      'message' => $message,
      'message_group' => $group,
      'function' => $caller['function'],
      'line' => $caller['line'],
      'file' => $caller['file'],
    );

    // Store assertion for display after the test has completed.
    db_insert('simpletest')->fields($assertion)->execute();

    // Return to testing prefix.
    $db_prefix = $current_db_prefix;
    return $status == 'pass' ? TRUE : FALSE;
  }

  /**
   * Cycles through backtrace until the first non-assertion method is found.
   *
   * @return
   *   Array representing the true caller.
   */
  protected function getAssertionCall() {
    $backtrace = debug_backtrace();

    // The first element is the call. The second element is the caller.
    // We skip calls that occured in one of the methods of DrupalWebTestCase
    // or in an assertion function.
    while (($caller = $backtrace[1]) &&
          ((isset($caller['class']) && $caller['class'] == 'DrupalWebTestCase') ||
            substr($caller['function'], 0, 6) == 'assert')) {
      // We remove that call.
      array_shift($backtrace);
    }

    return _drupal_get_last_caller($backtrace);
  }

  /**
   * Check to see if a value is not false (not an empty string, 0, NULL, or FALSE).
   *
   * @param $value
   *   The value on which the assertion is to be done.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertTrue($value, $message = '', $group = 'Other') {
    return $this->assert((bool) $value, $message ? $message : t('Value is TRUE'), $group);
  }

  /**
   * Check to see if a value is false (an empty string, 0, NULL, or FALSE).
   *
   * @param $value
   *   The value on which the assertion is to be done.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertFalse($value, $message = '', $group = 'Other') {
    return $this->assert(!$value, $message ? $message : t('Value is FALSE'), $group);
  }

  /**
   * Check to see if a value is NULL.
   *
   * @param $value
   *   The value on which the assertion is to be done.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertNull($value, $message = '', $group = 'Other') {
    return $this->assert(!isset($value), $message ? $message : t('Value is NULL'), $group);
  }

  /**
   * Check to see if a value is not NULL.
   *
   * @param $value
   *   The value on which the assertion is to be done.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertNotNull($value, $message = '', $group = 'Other') {
    return $this->assert(isset($value), $message ? $message : t('Value is not NULL'), $group);
  }

  /**
   * Check to see if two values are equal.
   *
   * @param $first
   *   The first value to check.
   * @param $second
   *   The second value to check.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertEqual($first, $second, $message = '', $group = 'Other') {
    return $this->assert($first == $second, $message ? $message : t('First value is equal to second value'), $group);
  }

  /**
   * Check to see if two values are not equal.
   *
   * @param $first
   *   The first value to check.
   * @param $second
   *   The second value to check.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertNotEqual($first, $second, $message = '', $group = 'Other') {
    return $this->assert($first != $second, $message ? $message : t('First value is not equal to second value'), $group);
  }

  /**
   * Check to see if two values are identical.
   *
   * @param $first
   *   The first value to check.
   * @param $second
   *   The second value to check.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertIdentical($first, $second, $message = '', $group = 'Other') {
    return $this->assert($first === $second, $message ? $message : t('First value is identical to second value'), $group);
  }

  /**
   * Check to see if two values are not identical.
   *
   * @param $first
   *   The first value to check.
   * @param $second
   *   The second value to check.
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE if the assertion succeeded, FALSE otherwise.
   */
  protected function assertNotIdentical($first, $second, $message = '', $group = 'Other') {
    return $this->assert($first !== $second, $message ? $message : t('First value is not identical to second value'), $group);
  }

  /**
   * Fire an assertion that is always positive.
   *
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   TRUE.
   */
  protected function pass($message = NULL, $group = 'Other') {
    return $this->assert(TRUE, $message, $group);
  }

  /**
   * Fire an assertion that is always negative.
   *
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @return
   *   FALSE.
   */
  protected function fail($message = NULL, $group = 'Other') {
    return $this->assert(FALSE, $message, $group);
  }

  /**
   * Fire an error assertion.
   *
   * @param $message
   *   The message to display along with the assertion.
   * @param $group
   *   The type of assertion - examples are "Browser", "PHP".
   * @param $caller
   *   The caller of the error.
   * @return
   *   FALSE.
   */
  protected function error($message = '', $group = 'Other', $caller = NULL) {
    return $this->assert('exception', $message, $group, $caller);
  }

  /**
   * Run all tests in this class.
   */
  public function run() {
    set_error_handler(array($this, 'errorHandler'));
    $methods = array();
    // Iterate through all the methods in this class.
    foreach (get_class_methods(get_class($this)) as $method) {
      // If the current method starts with "test", run it - it's a test.
      if (strtolower(substr($method, 0, 4)) == 'test') {
        $this->setUp();
        try {
          $this->$method();
          // Finish up.
        }
        catch (Exception $e) {
          $this->exceptionHandler($e);
        }
        $this->tearDown();
      }
    }
    // Clear out the error messages and restore error handler.
    drupal_get_messages();
    restore_error_handler();
  }

  /**
   * Handle errors.
   *
   * Because this is registered in set_error_handler(), it has to be public.
   * @see set_error_handler
   *
   */
  public function errorHandler($severity, $message, $file = NULL, $line = NULL) {
    if ($severity & error_reporting()) {
      $error_map = array(
        E_STRICT => 'Run-time notice',
        E_WARNING => 'Warning',
        E_NOTICE => 'Notice',
        E_CORE_ERROR => 'Core error',
        E_CORE_WARNING => 'Core warning',
        E_USER_ERROR => 'User error',
        E_USER_WARNING => 'User warning',
        E_USER_NOTICE => 'User notice',
        E_RECOVERABLE_ERROR => 'Recoverable error',
      );

      $backtrace = debug_backtrace();
      $this->error($message, $error_map[$severity], _drupal_get_last_caller($backtrace));
    }
    return TRUE;
  }

  /**
   * Handle exceptions.
   *
   * @see set_exception_handler
   */
  protected function exceptionHandler($exception) {
    $backtrace = $exception->getTrace();
    // Push on top of the backtrace the call that generated the exception.
    array_unshift($backtrace, array(
      'line' => $exception->getLine(),
      'file' => $exception->getFile(),
    ));
    $this->error($exception->getMessage(), 'Uncaught exception', _drupal_get_last_caller($backtrace));
  }

  /**
   * Creates a node based on default settings.
   *
   * @param $settings
   *   An associative array of settings to change from the defaults, keys are
   *   node properties, for example 'body' => 'Hello, world!'.
   * @return
   *   Created node object.
   */
  protected function drupalCreateNode($settings = array()) {
    // Populate defaults array
    $defaults = array(
      'body'      => $this->randomName(32),
      'title'     => $this->randomName(8),
      'comment'   => 2,
      'changed'   => REQUEST_TIME,
      'format'    => FILTER_FORMAT_DEFAULT,
      'moderate'  => 0,
      'promote'   => 0,
      'revision'  => 1,
      'log'       => '',
      'status'    => 1,
      'sticky'    => 0,
      'type'      => 'page',
      'revisions' => NULL,
      'taxonomy'  => NULL,
    );
    $defaults['teaser'] = $defaults['body'];
    // If we already have a node, we use the original node's created time, and this
    if (isset($defaults['created'])) {
      $defaults['date'] = format_date($defaults['created'], 'custom', 'Y-m-d H:i:s O');
    }
    if (empty($settings['uid'])) {
      global $user;
      $defaults['uid'] = $user->uid;
    }
    $node = ($settings + $defaults);
    $node = (object)$node;

    node_save($node);

    // small hack to link revisions to our test user
    db_query('UPDATE {node_revisions} SET uid = %d WHERE vid = %d', $node->uid, $node->vid);
    return $node;
  }

  /**
   * Creates a custom content type based on default settings.
   *
   * @param $settings
   *   An array of settings to change from the defaults.
   *   Example: 'type' => 'foo'.
   * @return
   *   Created content type.
   */
  protected function drupalCreateContentType($settings = array()) {
    // find a non-existent random type name.
    do {
      $name = strtolower($this->randomName(3, 'type_'));
    } while (node_get_types('type', $name));

    // Populate defaults array
    $defaults = array(
      'type' => $name,
      'name' => $name,
      'description' => '',
      'help' => '',
      'min_word_count' => 0,
      'title_label' => 'Title',
      'body_label' => 'Body',
      'has_title' => 1,
      'has_body' => 1,
    );
    // imposed values for a custom type
    $forced = array(
      'orig_type' => '',
      'old_type' => '',
      'module' => 'node',
      'custom' => 1,
      'modified' => 1,
      'locked' => 0,
    );
    $type = $forced + $settings + $defaults;
    $type = (object)$type;

    $saved_type = node_type_save($type);
    node_types_rebuild();

    $this->assertEqual($saved_type, SAVED_NEW, t('Created content type %type.', array('%type' => $type->type)));

    // Reset permissions so that permissions for this content type are available.
    $this->checkPermissions(array(), TRUE);

    return $type;
  }

  /**
   * Get a list files that can be used in tests.
   *
   * @param $type
   *   File type, possible values: 'binary', 'html', 'image', 'javascript', 'php', 'sql', 'text'.
   * @param $size
   *   File size in bytes to match. Please check the tests/files folder.
   * @return
   *   List of files that match filter.
   */
  protected function drupalGetTestFiles($type, $size = NULL) {
    $files = array();

    // Make sure type is valid.
    if (in_array($type, array('binary', 'html', 'image', 'javascript', 'php', 'sql', 'text'))) {
     // Use original file directory instead of one created during setUp().
      $path = $this->originalFileDirectory . '/simpletest';
      $files = file_scan_directory($path, '/' . $type . '\-.*/');

      // If size is set then remove any files that are not of that size.
      if ($size !== NULL) {
        foreach ($files as $file) {
          $stats = stat($file->filename);
          if ($stats['size'] != $size) {
            unset($files[$file->filename]);
          }
        }
      }
    }
    usort($files, array($this, 'drupalCompareFiles'));
    return $files;
  }

  /**
   * Compare two files based on size and file name.
   */
  protected function drupalCompareFiles($file1, $file2) {
    // Determine which file is larger.
    $compare_size = (filesize($file1->filename) > filesize($file2->filename));
    if (!$compare_size) {
      // Both files were the same size, so return whichever one is alphabetically greater.
      return strnatcmp($file1->name, $file2->name);
    }
    else {
      // Return TRUE if $file1 is larger than $file2.
      return $compare_size;
    }
  }

  /**
   * Generates a random string.
   *
   * @param $number
   *   Number of characters in length to append to the prefix.
   * @param $prefix
   *   Prefix to use.
   * @return
   *   Randomly generated string.
   */
  public static function randomName($number = 4, $prefix = 'simpletest_') {
    $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_';
    for ($x = 0; $x < $number; $x++) {
      $prefix .= $chars{mt_rand(0, strlen($chars) - 1)};
      if ($x == 0) {
        $chars .= '0123456789';
      }
    }
    return $prefix;
  }

  /**
   * Create a user with a given set of permissions. The permissions correspond to the
   * names given on the privileges page.
   *
   * @param $permissions
   *   Array of permission names to assign to user.
   * @return
   *   A fully loaded user object with pass_raw property, or FALSE if account
   *   creation fails.
   */
  protected function drupalCreateUser($permissions = NULL) {
    // Create a role with the given permission set.
    if (!($rid = $this->_drupalCreateRole($permissions))) {
      return FALSE;
    }

    // Create a user assigned to that role.
    $edit = array();
    $edit['name']   = $this->randomName();
    $edit['mail']   = $edit['name'] . '@example.com';
    $edit['roles']  = array($rid => $rid);
    $edit['pass']   = user_password();
    $edit['status'] = 1;

    $account = user_save('', $edit);

    $this->assertTrue(!empty($account->uid), t('User created with name %name and pass %pass', array('%name' => $edit['name'], '%pass' => $edit['pass'])), t('User login'));
    if (empty($account->uid)) {
      return FALSE;
    }

    // Add the raw password so that we can log in as this user.
    $account->pass_raw = $edit['pass'];
    return $account;
  }

  /**
   * Internal helper function; Create a role with specified permissions.
   *
   * @param $permissions
   *   Array of permission names to assign to role.
   * @return
   *   Role ID of newly created role, or FALSE if role creation failed.
   */
  protected function _drupalCreateRole(Array $permissions = NULL) {
    // Generate string version of permissions list.
    if ($permissions === NULL) {
      $permissions = array('access comments', 'access content', 'post comments', 'post comments without approval');
    }

    if (!$this->checkPermissions($permissions)) {
      return FALSE;
    }

    // Create new role.
    $role_name = $this->randomName();
    db_query("INSERT INTO {role} (name) VALUES ('%s')", $role_name);
    $role = db_fetch_object(db_query("SELECT * FROM {role} WHERE name = '%s'", $role_name));
    $this->assertTrue($role, t('Created role of name: @role_name, id: @rid', array('@role_name' => $role_name, '@rid' => (isset($role->rid) ? $role->rid : t('-n/a-')))), t('Role'));
    if ($role && !empty($role->rid)) {
      // Assign permissions to role and mark it for clean-up.
      foreach ($permissions as $permission_string) {
        db_query("INSERT INTO {role_permission} (rid, permission) VALUES (%d, '%s')", $role->rid, $permission_string);
      }
      $count = db_result(db_query("SELECT COUNT(*) FROM {role_permission} WHERE rid = %d", $role->rid));
      $this->assertTrue($count == count($permissions), t('Created permissions: @perms', array('@perms' => implode(', ', $permissions))), t('Role'));
      return $role->rid;
    }
    else {
      return FALSE;
    }
  }

  /**
   * Check to make sure that the array of permissions are valid.
   *
   * @param $permissions
   *   Permissions to check.
   * @param $reset
   *   Reset cached available permissions.
   * @return
   *   TRUE or FALSE depending on whether the permissions are valid.
   */
  protected function checkPermissions(Array $permissions, $reset = FALSE) {
    static $available;

    if (!isset($available) || $reset) {
      $available = array_keys(module_invoke_all('perm'));
    }

    $valid = TRUE;
    foreach ($permissions as $permission) {
      if (!in_array($permission, $available)) {
        $this->fail(t('Invalid permission %permission.', array('%permission' => $permission)), t('Role'));
        $valid = FALSE;
      }
    }
    return $valid;
  }

  /**
   * Logs in a user with the internal browser. If already logged in then logs the current
   * user out before logging in the specified user. If no user is specified then a new
   * user will be created and logged in.
   *
   * @param $user
   *   User object representing the user to login.
   * @return
   *   User that was logged in. Useful if no user was passed in order to retrieve
   *   the created user.
   */
  protected function drupalLogin($user = NULL) {
    if ($this->isLoggedIn) {
      $this->drupalLogout();
    }

    if (!isset($user)) {
      $user = $this->_drupalCreateRole();
    }

    $edit = array(
      'name' => $user->name,
      'pass' => $user->pass_raw
    );
    $this->drupalPost('user', $edit, t('Log in'));

    $pass = $this->assertText($user->name, t('Found name: %name', array('%name' => $user->name)), t('User login'));
    $pass = $pass && $this->assertNoText(t('The username %name has been blocked.', array('%name' => $user->name)), t('No blocked message at login page'), t('User login'));
    $pass = $pass && $this->assertNoText(t('The name %name is a reserved username.', array('%name' => $user->name)), t('No reserved message at login page'), t('User login'));

    $this->isLoggedIn = $pass;

    return $user;
  }

  /*
   * Logs a user out of the internal browser, then check the login page to confirm logout.
   */
  protected function drupalLogout() {
    // Make a request to the logout page.
    $this->drupalGet('user/logout');

    // Load the user page, the idea being if you were properly logged out you should be seeing a login screen.
    $this->drupalGet('user');
    $pass = $this->assertField('name', t('Username field found.'), t('Logout'));
    $pass = $pass && $this->assertField('pass', t('Password field found.'), t('Logout'));

    $this->isLoggedIn = !$pass;
  }

  /**
   * Generates a random database prefix, runs the install scripts on the
   * prefixed database and enable the specified modules. After installation
   * many caches are flushed and the internal browser is setup so that the
   * page requests will run on the new prefix. A temporary files directory
   * is created with the same name as the database prefix.
   *
   * @param ...
   *   List of modules to enable for the duration of the test.
   */
  protected function setUp() {
    global $db_prefix;

    // Store necessary current values before switching to prefixed database.
    $this->originalPrefix = $db_prefix;
    $clean_url_original = variable_get('clean_url', 0);

    // Generate temporary prefixed database to ensure that tests have a clean starting point.
    $db_prefix = Database::getActiveConnection()->prefixTables('{simpletest' . mt_rand(1000, 1000000) . '}');

    include_once DRUPAL_ROOT . '/includes/install.inc';
    drupal_install_system();

    // Add the specified modules to the list of modules in the default profile.
    $args = func_get_args();
    $modules = array_unique(array_merge(drupal_get_profile_modules('default', 'en'), $args));
    drupal_install_modules($modules);

    // Because the schema is static cached, we need to flush
    // it between each run.  If we don't, then it will contain
    // stale data for the previous run's database prefix and all
    // calls to it will fail.
    drupal_get_schema(NULL, TRUE);

    // Run default profile tasks.
    $task = 'profile';
    default_profile_tasks($task, '');

    // Rebuild caches.
    menu_rebuild();
    actions_synchronize();
    _drupal_flush_css_js();
    $this->refreshVariables();
    $this->checkPermissions(array(), TRUE);

    // Restore necessary variables.
    variable_set('install_profile', 'default');
    variable_set('install_task', 'profile-finished');
    variable_set('clean_url', $clean_url_original);

    // Use temporary files directory with the same prefix as database.
    $this->originalFileDirectory = file_directory_path();
    variable_set('file_directory_path', file_directory_path() . '/' . $db_prefix);
    $directory = file_directory_path();
    file_check_directory($directory, FILE_CREATE_DIRECTORY); // Create the files directory.
  }

  /**
   * Refresh the in-memory set of variables. Useful after a page request is made
   * that changes a variable in a different thread.
   *
   * In other words calling a settings page with $this->drupalPost() with a changed
   * value would update a variable to reflect that change, but in the thread that
   * made the call (thread running the test) the changed variable would not be
   * picked up.
   *
   * This method clears the variables cache and loads a fresh copy from the database
   * to ensure that the most up-to-date set of variables is loaded.
   */
  protected function refreshVariables() {
    global $conf;
    cache_clear_all('variables', 'cache');
    $conf = variable_init();
  }

  /**
   * Delete created files and temporary files directory, delete the tables created by setUp(),
   * and reset the database prefix.
   */
  protected function tearDown() {
    global $db_prefix;
    if (preg_match('/simpletest\d+/', $db_prefix)) {
      // Delete temporary files directory and reset files directory path.
      simpletest_clean_temporary_directory(file_directory_path());
      variable_set('file_directory_path', $this->originalFileDirectory);

      // Remove all prefixed tables (all the tables in the schema).
      $schema = drupal_get_schema(NULL, TRUE);
      $ret = array();
      foreach ($schema as $name => $table) {
        db_drop_table($ret, $name);
      }

      // Return the database prefix to the original.
      $db_prefix = $this->originalPrefix;

      // Ensure that the internal logged in variable is reset.
      $this->isLoggedIn = FALSE;

      // Reload module list and implementations to ensure that test module hooks
      // aren't called after tests.
      module_list(TRUE);
      module_implements(MODULE_IMPLEMENTS_CLEAR_CACHE);

      // Rebuild caches.
      $this->refreshVariables();

      // Close the CURL handler.
      $this->curlClose();
    }
  }

  /**
   * Initializes the cURL connection.
   *
   * This function will add authentication headers as specified in the
   * simpletest_httpauth_username and simpletest_httpauth_pass variables. Also,
   * see the description of $curl_options among the properties.
   */
  protected function curlInitialize() {
    global $base_url, $db_prefix;
    if (!isset($this->curlHandle)) {
      $this->curlHandle = curl_init();
      $curl_options = $this->additionalCurlOptions + array(
        CURLOPT_COOKIEJAR => $this->cookieFile,
        CURLOPT_URL => $base_url,
        CURLOPT_FOLLOWLOCATION => TRUE,
        CURLOPT_RETURNTRANSFER => TRUE,
        CURLOPT_SSL_VERIFYPEER => FALSE,  // Required to make the tests run on https://
        CURLOPT_SSL_VERIFYHOST => FALSE,  // Required to make the tests run on https://
        CURLOPT_HEADERFUNCTION => array(&$this, 'curlHeaderCallback'),
      );
      if (preg_match('/simpletest\d+/', $db_prefix, $matches)) {
        $curl_options[CURLOPT_USERAGENT] = $matches[0];
      }
      if (!isset($curl_options[CURLOPT_USERPWD]) && ($auth = variable_get('simpletest_httpauth_username', ''))) {
        if ($pass = variable_get('simpletest_httpauth_pass', '')) {
          $auth .= ':' . $pass;
        }
        $curl_options[CURLOPT_USERPWD] = $auth;
      }
      curl_setopt_array($this->curlHandle, $this->additionalCurlOptions + $curl_options);
    }
  }

  /**
   * Performs a cURL exec with the specified options after calling curlConnect().
   *
   * @param $curl_options
   *   Custom cURL options.
   * @return
   *   Content returned from the exec.
   */
  protected function curlExec($curl_options) {
    $this->curlInitialize();
    $url = empty($curl_options[CURLOPT_URL]) ? curl_getinfo($this->curlHandle, CURLINFO_EFFECTIVE_URL) : $curl_options[CURLOPT_URL];
    curl_setopt_array($this->curlHandle, $this->additionalCurlOptions + $curl_options);
    $this->drupalSetContent(curl_exec($this->curlHandle), curl_getinfo($this->curlHandle, CURLINFO_EFFECTIVE_URL));
    $this->assertTrue($this->content !== FALSE, t('!method to !url, response is !length bytes.', array('!method' => !empty($curl_options[CURLOPT_NOBODY]) ? 'HEAD' : (empty($curl_options[CURLOPT_POSTFIELDS]) ? 'GET' : 'POST'), '!url' => $url, '!length' => strlen($this->content))), t('Browser'));
    return $this->drupalGetContent();
  }

  /**
   * Reads headers and registers errors received from the tested site.
   *
   * @see _drupal_log_error().
   *
   * @param $curlHandler
   *   The cURL handler.
   * @param $header
   *   An header.
   */
  protected function curlHeaderCallback($curlHandler, $header) {
    // Errors are being sent via X-Drupal-Assertion-* headers,
    // generated by _drupal_log_error() in the exact form required
    // by DrupalWebTestCase::error().
    if (preg_match('/^X-Drupal-Assertion-[0-9]+: (.*)$/', $header, $matches)) {
      // Call DrupalWebTestCase::error() with the parameters from the header.
      call_user_func_array(array(&$this, 'error'), unserialize(urldecode($matches[1])));
    }
    // This is required by cURL.
    return strlen($header);
  }

  /**
   * Close the cURL handler and unset the handler.
   */
  protected function curlClose() {
    if (isset($this->curlHandle)) {
      curl_close($this->curlHandle);
      unset($this->curlHandle);
    }
  }

  /**
   * Parse content returned from curlExec using DOM and SimpleXML.
   *
   * @return
   *   A SimpleXMLElement or FALSE on failure.
   */
  protected function parse() {
    if (!$this->elements) {
      // DOM can load HTML soup. But, HTML soup can throw warnings, supress
      // them.
      @$htmlDom = DOMDocument::loadHTML($this->content);
      if ($htmlDom) {
        $this->pass(t('Valid HTML found on "@path"', array('@path' => $this->getUrl())), t('Browser'));
        // It's much easier to work with simplexml than DOM, luckily enough
        // we can just simply import our DOM tree.
        $this->elements = simplexml_import_dom($htmlDom);
      }
    }
    if (!$this->elements) {
      $this->fail(t('Parsed page successfully.'), t('Browser'));
    }

    return $this->elements;
  }

  /**
   * Retrieves a Drupal path or an absolute path.
   *
   * @param $path
   *   Drupal path or URL to load into internal browser
   * @param $options
   *   Options to be forwarded to url().
   * @return
   *   The retrieved HTML string, also available as $this->drupalGetContent()
   */
  protected function drupalGet($path, $options = array()) {
    $options['absolute'] = TRUE;

    // We re-using a CURL connection here.  If that connection still has certain
    // options set, it might change the GET into a POST.  Make sure we clear out
    // previous options.
    $out = $this->curlExec(array(CURLOPT_HTTPGET => TRUE, CURLOPT_URL => url($path, $options), CURLOPT_HEADER => FALSE, CURLOPT_NOBODY => FALSE));
    $this->refreshVariables(); // Ensure that any changes to variables in the other thread are picked up.

    // Replace original page output with new output from redirected page(s).
    if (($new = $this->checkForMetaRefresh())) {
      $out = $new;
    }
    return $out;