Note when new HTLC state can be `None`

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index d1c7a5ee5f83e369b7ae20e52476633ac6611a92..31989a011a971b5dc55f170eac5e3de9e99205b2 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -247,9 +247,14 @@ pub struct InboundHTLCDetails {
        /// The payment hash.
        pub payment_hash: PaymentHash,
        /// The state of the HTLC in the state machine.
+       ///
        /// Determines on which commitment transactions the HTLC is included and what message the HTLC is
        /// waiting for to advance to the next state.
+       ///
        /// See [`InboundHTLCStateDetails`] for information on the specific states.
+       ///
+       /// LDK will always fill this field in, but when downgrading to prior versions of LDK, new
+       /// states may result in `None` here.
        pub state: Option<InboundHTLCStateDetails>,
        /// Whether the HTLC has an output below the local dust limit. If so, the output will be trimmed
        /// from the local commitment transaction and added to the commitment transaction fee.
@@ -428,9 +433,14 @@ pub struct OutboundHTLCDetails {
        /// The payment hash.
        pub payment_hash: PaymentHash,
        /// The state of the HTLC in the state machine.
+       ///
        /// Determines on which commitment transactions the HTLC is included and what message the HTLC is
        /// waiting for to advance to the next state.
+       ///
        /// See [`OutboundHTLCStateDetails`] for information on the specific states.
+       ///
+       /// LDK will always fill this field in, but when downgrading to prior versions of LDK, new
+       /// states may result in `None` here.
        pub state: Option<OutboundHTLCStateDetails>,
        /// The extra fee being skimmed off the top of this HTLC.
        pub skimmed_fee_msat: Option<u64>,