Pass if the text is NOT found on the text version of the page. The text version is the equivalent of what a user would see when viewing through a web browser. In other words the HTML has been filtered out of the contents.
$text: Plain text to look for.
$message: (optional) A message to display with the assertion. Do not translate messages: use format_string() to embed variables in the message text, not t(). If left blank, a default message will be displayed.
$group: (optional) The group this message is in, which is displayed in a column in test output. Use 'Debug' to indicate this is debugging output. Do not translate this string. Defaults to 'Other'; most tests do not override this default.
TRUE on pass, FALSE on fail.
protected function assertNoText($text, $message = '', $group = 'Other') {
return $this
->assertTextHelper($text, $message, $group, TRUE);
}