f - expand verify_signature docs

Author: jkczyz

lightning/src/offers/merkle.rs

@@ -26,6 +26,8 @@ tlv_stream!(SignatureTlvStream, SignatureTlvStreamRef, SIGNATURE_TYPES, {
 
 /// Verifies the signature with a pubkey over the given bytes using a tagged hash as the message
 /// digest.
+///
+/// Assumes `bytes` is a well-formed TLV stream containing at least one TLV record.
 pub(super) fn verify_signature(
 	signature: &Signature, tag: &str, bytes: &[u8], pubkey: PublicKey,
 ) -> Result<(), secp256k1::Error> {