send method
Send request and return a GatewayHandoffResponse.
Throws GatewayError for any transport-level failure.
Implementation
@override
Future<GatewayHandoffResponse> send(
GatewayTransactionRequest request,
) async {
requests.add(request);
final h = handler;
if (h != null) return h(request);
return const GatewayHandoffResponse(
status: GatewayHandoffStatus.approved,
approved: true,
transactionId: 'fake-tx-1',
responseCode: '00',
);
}