@dataProvider getInvalidDateTimes
public function testInvalidDateTimes($dateTime) {
$constraint = new DateTime(array(
'message' => 'myMessage',
));
$this->context
->expects($this
->once())
->method('addViolation')
->with('myMessage', array(
'{{ value }}' => $dateTime,
));
$this->validator
->validate($dateTime, $constraint);
}