# You can use Stripe constants like this:
\Stripe\PaymentIntent::STATUS_CANCELED;
\Stripe\PaymentIntent::STATUS_PROCESSING;
\Stripe\PaymentIntent::STATUS_SUCCEEDED;
...

\Stripe\Cahrge::STATUS_FAILED;
\Stripe\Cahrge::STATUS_PENDING;
\Stripe\Cahrge::STATUS_SUCCEEDED;
...

You can find the rest in the repo 
# https://github.com/stripe/stripe-php/tree/master/lib