Function has_accepted_keysend_htlc 

fn has_accepted_keysend_htlc(htlcs: &[InvoiceHtlc]) -> bool

Whether a HOLD invoice accepted an HTLC without an MPP total. For the non-blinded HOLD invoices the gateway creates, standard LND builds require the payment address, which travels in the MPP record, from every HTLC except one carrying a keysend record. Since LND v0.20.3 and v0.21.2 that record must hold the invoice’s preimage; before, any value passes unless accept-keysend is on.