Bug report

This only started on phpstan 0.12.8.

Code snippet that reproduces the problem

		/** @var \Ds\Map<PaymentGroupId, array<Payment>> $paymentsByGroup */
		$paymentsByGroup = new \Ds\Map();
		$paymentGroup = $paymentsByGroup->get($paymentGroupId, []);
		$paymentGroup[] = Payment::fromValues(...);

The last line triggers this error:

Cannot access an offset on array<App\Module\PaymentRegistry\Domain\PaymentGroup\ValueObject\Payment>|TDefault.

Something is wrong here - TDefault is a generic type in Map::get() so it makes no sense that the error refers to it. Also it is actually an array in this case which means that $paymentGroup will always be an array.

Expected output

no error