lots of refactoring

beacon_node/beacon_chain/src/blob_verification.rs

@@ -511,7 +511,7 @@ impl<T: EthSpec> TryInto<AvailableBlock<T>> for MaybeAvailableBlock<T> {
     fn try_into(self) -> Result<AvailableBlock<T>, Self::Error> {
         match self {
             Self::Available(block) => Ok(block),
-            Self::AvailabilityPending(block) => Err(AvailabilityCheckError::MissingBlobs),
+            Self::AvailabilityPending(_block) => Err(AvailabilityCheckError::MissingBlobs),
         }
     }
 }

beacon_node/beacon_chain/src/block_verification.rs

@@ -312,7 +312,9 @@ pub enum BlockError<T: EthSpec> {
     ParentExecutionPayloadInvalid {
         parent_root: Hash256,
     },
+    /// The blob alone failed validation.
     BlobValidation(BlobError<T>),
+    /// The block and blob together failed validation.
     AvailabilityCheck(AvailabilityCheckError),
     MissingBlockParts(Slot, Hash256),
 }

beacon_node/beacon_chain/src/data_availability_checker.rs

@@ -37,6 +37,7 @@ pub enum AvailabilityCheckError {
     SszTypes(ssz_types::Error),
     MissingBlobs,
     NumBlobsMismatch {
+        /// The peer sent us an invalid block, we must penalise harshly.
         num_kzg_commitments: usize,
         num_blobs: usize,
     },