/**
* Validator method used to check the uniqueness of a value for a column.
* This is meant to be used with the validation API and not to be called
* directly.
*
* ### Example:
*
* {{{
* $validator->add('email', [
* 'unique' => ['rule' => 'validateUnique', 'provider' => 'table']
* ])
* }}}
*
* Unique validation can be scoped to the value of another column:
*
* {{{
* $validator->add('email', [
* 'unique' => [
* 'rule' => ['validateUnique', ['scope' => 'site_id']],
* 'provider' => 'table'
* ]
* ]);
* }}}
*
* In the above example, the email uniqueness will be scoped to only rows having
* the same site_id. Scoping will only be used if the scoping field is present in
* the data to be validated.
*
* @override To allow multiple scoped values
*
* @param mixed $value The value of column to be checked for uniqueness
* @param array $options The options array, optionally containing the 'scope' key
* @param array $context The validation context as provided by the validation routine
* @return bool true if the value is unique
*/
public function validateUniqueExt($value, array $options, array $context = [])
{
$context += $options;
return parent::validateUnique($value, $context);
}
