public function testExceptionAwareness()
{
$variant = new Variant($this->subject->reveal(), $this->parameterSet->reveal(), 10, 20);
$error = new \Exception('Test');
$this->assertFalse($variant->hasErrorStack());
$variant->setException($error);
$this->assertTrue($variant->hasErrorStack());
$this->assertEquals('Test', $variant->getErrorStack()->getTop()->getMessage());
}