Creates sample article nodes.
$count: (optional) The number of nodes to generate. Defaults to five.
function createSampleNodes($count = 5) {
  $langcode = Language::LANGCODE_NOT_SPECIFIED;
  // Post $count article nodes.
  for ($i = 0; $i < $count; $i++) {
    $edit = array();
    $edit['title'] = $this
      ->randomName();
    $edit["body[{$langcode}][0][value]"] = $this
      ->randomName();
    $this
      ->drupalPost('node/add/article', $edit, t('Save'));
  }
}