/**
* Validate the equations in the some question content.
* @param array $errors where errors are being accumulated.
* @param string $field the field being validated.
* @param string $text the content of that field.
* @return array the updated $errors array.
*/
protected function validate_text($errors, $field, $text)
{
$problems = qtype_calculated_find_formula_errors_in_text($text);
if ($problems) {
$errors[$field] = $problems;
}
return $errors;
}
/**
* Verify that the equations in part of the question are OK.
* We throw an exception here because this should have already been validated
* by the form. This is just a last line of defence to prevent a question
* being stored in the database if it has bad formulas. This saves us from,
* for example, malicious imports.
* @param string $text containing equations.
*/
protected function validate_text($text)
{
$error = qtype_calculated_find_formula_errors_in_text($text);
if ($error) {
throw new coding_exception($error);
}
}
public function test_validation_of_formulas_in_text_bad_function()
{
$this->assert_nonempty_string(qtype_calculated_find_formula_errors_in_text('<p>This is an equation: {=eval(1)}.</p>'));
$this->assert_nonempty_string(qtype_calculated_find_formula_errors_in_text('<p>Good: {=1+1}, bad: {=eval(1)}, good: {={x}+{y}}.</p>'));
$this->assert_nonempty_string(qtype_calculated_find_formula_errors_in_text('<p>Bad: {=eval(1)}, bad: {=system(1)}.</p>'));
}
